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Sample records for homoptera aleyrodidae b-biotype

  1. Reproduction of the whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) B biotype in maize fields (Zea mays L.) in Brazil.

    Science.gov (United States)

    Quintela, Eliane D; Abreu, Aluana G; Lima, Julyana F Dos S; Mascarin, Gabriel M; Santos, Jardel B Dos; Brown, Judith K

    2016-11-01

    Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) was observed to have completed its reproductive cycle from the egg to the adult on maize (Zea mays L.). Field and screenhouse studies were carried out to investigate the durability of this putative and unprecedented adaptation to a grass host. Analysis of the mitochondrial COI gene sequence identified the maize-associated B. tabaci as the exotic B biotype (major clade North Africa-Mediterranean-Middle East). Results showed that whiteflies migrated from soybean crops and successfully established in maize plants. Females exhibited a preference for oviposition primarily on the first and second leaves of maize, but were also able to colonise developing leaves. A high, natural infestation on maize (193.3 individuals, all developmental stages) was observed within a 7.1 cm2 designated 'observation area'. Whiteflies collected from naturally infested maize leaves and allowed to oviposit on maize seedlings grown in a screenhouse developed from egg to adulthood in 28.6 ± 0.2 days. This is the first report of the B biotype completing its development on maize plants. This surprising anomaly indicates that the B biotype is capable of adapting to monocotyledonous host plants, and importantly, broadens the host range to include at least one species in the Poaceae. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  2. Biological aspects of Bemisia tabaci (Genn.) B biotype (Hemiptera: Aleyrodidae) on six bean genotypes; Aspectos biologicos de Bemisia tabaci (Genn.) biotipo B (Hemiptera: Aleyrodidae) em seis genotipos de feijoeiro

    Energy Technology Data Exchange (ETDEWEB)

    Oriani, Maria A. de G. [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Ecologia e Biologia Evolutiva; Vendramin, Jose D. [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Dept. de Entomologia, Fitopatologia e Zoologia Agricola; Brunherotto, Rogerio [Fundacao Municipal de Ensino Superior de Braganca Paulista, SP (Brazil)

    2008-03-15

    The silverleaf whitefly is one of the most harmful pests that attack bean crops, mainly for extracting large quantities of phloem sap and transmitting the bean golden mosaic virus. Resistant germplasm plants can be an important method for controlling this pest. The biological aspects of Bemisia tabaci B biotype on bean (Phaseolus vulgaris) genotypes were evaluated. The tests were conducted under laboratory conditions, with the following genotypes: Arc 1, Arc 3s, Arc 5s, G13028, G11056 and Porrillo 70. The bean plants in a stage IV-1 were infested during one day with silverleaf white flies. Afterwards the eggs and nymphs were observed until adult emergence. Longevity and fecundity of emerged insects were also evaluated. The longest development time occurred for nymphs fed on Arc 3s genotype (26.5 days), following by G11056 (25.9 days) and G13028 (25.3 days). The development period was 5.5 days longer in Arc 3s when compared with Porrillo 70. Also, the wild genotypes Arc 3s and G11056 showed higher mortality rates (94.7% and 83.1%, respectively), which may suggest antibiosis and/or feeding non preference resistance type. For this reason, although longevity and fecundity were not influenced when the whitefly fed on resistant genotypes (Arc 3s, G11056, G13028 and Arc 5s), those genotypes can be used for bean breeding program towards B. tabaci B biotype. (author)

  3. Controle químico de ovos e ninfas de Bemisia tabaci biótipo B (Hemiptera: aleyrodidae Chemical control of Bemisia tabaci B biotype (Hemiptera: aleyrodidae eggs and nymphs

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    Giuliana Etore do Valle

    2002-06-01

    Full Text Available Moscas brancas são pragas de diversas culturas, causam redução na produção e na qualidade do produto. Inseticidas, com diferentes modos de ação vêm sendo utilizados, sem muito sucesso. Neste trabalho avaliou-se a eficiência de inseticidas sobre ovos de diferentes idades (1, 3 e 5 dias e de ninfas de 1° ínstar da mosca branca Bemisia tabaci biótipo B. Os experimentos foram realizados em condições de laboratório, sob temperatura de 25 ± 2°C e fotofase de 12 horas. Piriproxifem (75 mg L-1 atuou como excelente ovicida, sendo altamente eficiente, 3 dias de idade. Cartape (500 mg L-1 não teve efeito satisfatório, mas a 1000 mg L-1 foi eficiente em ovos com até 5 dias de idade. Quanto à ação sobre ninfas de 1° ínstar, para pulverizações na face superior das folhas, piriproxifem, a 75 mg L-1, apresentou eficiência na supressão da emergência de adultos, caracterizando presença de ação translaminar; buprofezim, cartape, acefato e fempiroximate não apresentaram eficiência no controle de ninfas. Quando aplicado na face inferior das folhas, buprofezim (375 mg L-1 apresentou eficiência comparável à de piriproxifem, impedindo a emergência de adultos.Whiteflies are pests of many crops, cause severe yield losses and reduce crop quality. Insecticides of different modes of action have been used without success. In this work, the efficiency of five insecticides on Bemisia tabaci B biotype (= B. argentifolii eggs and nymphs was evaluated under laboratory conditions (T = 25 ± 2°C; 12 h photophase. In relation to the ovicidal effect, pyriproxyfen (75 mg L-1 caused egg hatching inhibition up to three day old eggs. Cartap showed efficiency only at the concentration of 1000 mg L-1, supressing the viability of eggs up to five days. Soybean leaves with first instar nymphs were treated in the upper surface with pyriproxyfen (75 mg L-1, buprofezin (375 mg L-1, cartap (1000 mg L-1, acephate (750 mg L-1 and fenpyroximate (100 mg L-1; in

  4. Biology of Bemisia tabaci (Genn. B biotype (Hemiptera, Aleyrodidae on tomato genotypes Biologia de Bemisia tabaci (Genn. Biótipo B (Hemiptera, Aleyrodidae em genótipos de tomateiro

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    Maria Auxiliadora de Godoy Oriani

    2011-02-01

    Full Text Available Brazil is one of the main tomato (Solanum lycopersicum producers worldwide. Nevertheless, considerable part of the production is lost due to Bemisia tabaci (Genn. B biotype attacks. Resistant plants can be an important method for controlling this pest in an integrated pest management. Tests for evaluating some biological aspects of B. tabaci were carried out on 18 tomato genotypes, in controlled laboratory greenhouse conditions. Thirty-day-old plants placed in plastic cages were infested with 20 whitefly pairs each, for 24 h. The development of at least 30 eggs in three leaflets per plant (repetition was observed until adult emergence. The development period of insects grown in LA1335, PI365928 and LA722 genotypes took three days longer when compared to the ones grown in PI134418 (20.3 days. The highest mortality rate of whitefly nymphs occurred in PI365928, LA1335 and LA722 genotypes (63.8, 54.5 and 53.3%, respectively, and the smallest ones in IAC294 and IAC68F-22-2 genotypes (4.9 e 6.2%, respectively. LA1335, PI365928 and LA722 genotypes presented moderate feeding nonpreference and/or antibiosis-based resistance to B. tabaci B biotype.O Brasil é um dos maiores produtores mundiais de tomate (Solanum lycopersicum, porém grande parte da produção é perdida devido ao ataque de Bemisia tabaci (Genn. biótipo B. Entre as táticas de controle dessa praga num manejo integrado de pragas, pode-se relacionar a resistência de plantas. Ensaios para avaliar alguns aspectos biológicos de B. tabaci foram realizados com 18 genótipos de tomateiro, em condições controladas de laboratório (casa de vegetação. Plantas com 30 dias de idade foram colocadas em gaiolas plásticas e infestadas com 20 casais de moscas-brancas cada, durante 24h. Acompanhou-se então o desenvolvimento de pelo menos 30 ovos em três folíolos por planta (repetição até a emergência dos insetos. Os insetos criados nos genótipos LA1335, PI365928 e LA722 apresentaram

  5. Densidades y frecuencias de liberación de Encarsia formosa (Hymenoptera: Aphelinidae) sobre Trialeurodes vaporariorum (Homoptera: Aleyrodidae) en tomate

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    Tello Paola; Cantor Fernando; Rodríguez Daniel; Cure José Ricardo

    2007-01-01

    La mosca blanca de los invernaderos, Trialeurodes vaporariorum (Westwood) (Homoptera: Aleyrodidae) es una de las plagas más importantes de cultivos de tomate bajo invernadero en la Sabana de Bogotá. Para su control tradicionalmente se acude a la aplicación de insecticidas. Sin embargo, también son contempladas liberaciones del parasitoide Encarsia formosa (Gahan) (Hymenoptera: Aphelinidae). Para estandarizar el proceso de cría mas...

  6. Spread of the spiraling white fly Aleurodicus dispersus (Homoptera ...

    African Journals Online (AJOL)

    Spread of the spiraling white fly Aleurodicus dispersus (Homoptera: Aleyrodidae) and its parasitoids Encarcia species (Hymenoptera: Aphelinidae) on horticultural plants in Northwest and Central Nigeria.

  7. Actividad fagodisuasiva de las plantas Tithonia diversifolia y Montanoa hibiscifolia (Asteraceae sobre adultos del insecto plaga Bemisia tabaci (Homoptera: Aleyrodidae

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    Gina Bagnarello

    2009-12-01

    Full Text Available Bemisia tabaci (Gennadius (Homoptera: Aleyrodidae es una plaga polífaga, cosmopolita y de gran relevancia mundial, sobre todo como vector de virus en numerosos cultivos, por lo que sería deseable un enfoque preventivo para su manejo. En tal sentido, podría recurrirse a la utilización de sustancias repelentes o disuasivas, algunas de ellas presentes en plantas tropicales, lo cual contribuiría al aprovechamiento de la rica biodiversidad mesoamericana. Por tanto, se evaluó la posible actividad fagodisuasiva sobre los adultos de B. tabaci de dos especies silvestres de la familia Asteraceae: titonia (Tithonia diversifolia (Hemsl. A. Gray y tora (Montanoa hibiscifolia Benth.. Para ello, en condiciones de invernadero se evaluaron los extractos crudos y cuatro fracciones (hexano, diclorometano, acetato de etilo y metanol de ambas especies, a los cuales se les hizo un análisis fitoquímico (tamizaje el cual permitió determinar cuáles metabolitos presentes en T. diversifolia y M. hibiscifolia podrían causar fagodisuasión en B. tabaci. Se realizaron dos tipos de experimentos: de escogencia restringida y de escogencia irrestricta. En los primeros, cada fracción se evaluó a cuatro dosis (0.1, 0.5, 1.0 y 1.5% v/v, y se comparó con cuatro tratamientos testigo: aceite agrícola, endosulfán, un emulsificante (Citowett y un testigo absoluto (agua. Se asperjaron plantas de tomate colocadas dentro de jaulas de manga, donde se liberaron 50 adultos de B. tabaci. Para determinar si existía fagodisuasión se utilizó como criterio el número de adultos posados a las 48h. Para el experimento de escogencia irrestricta se utilizaron las dos concentraciones más altas (1.0 y 1.5% del extracto crudo de cada especie y se compararon con el aceite agrícola y agua. Los extractos crudos de titonia y tora causaron fagodisuasión, y para ambas especies la fracción de metanol fue la que más sobresalió. En conclusión, los resultados obtenidos en los bioensayos

  8. Parâmetros biológicos de Bemisia Tabaci (genn. biótipo B (hemiptera: aleyrodidae em genótipos de algodoeiro Biological parameters of Bemisia Tabaci B biotype on cotton genotypes

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    Zeneide Ribeiro Campos

    2009-01-01

    Full Text Available A mosca-branca Bemisia tabaci biótipo B é uma praga de grande importância econômica para muitas culturas em todo o mundo. No Brasil, especialmente no Estado da Bahia, essa praga causou perdas que variam entre 30% e 70% em cultura de algodão. Essa pesquisa foi desenvolvida com o objetivo de avaliar parâmetros biológicos de B. tabaci biótipo B em genótipos de algodoeiro para verificar a possível ocorrência de antibiose como mecanismo de resistência sob condições de casa de vegetação. Os genótipos estudados foram IAC-23, Coodetec 406, BRS Aroeira, Fabrika, Coodetec 407, IAC-24, Makina, IAC 20-233, Coodetec 401 e CNPA Acala I. Foram avaliados os períodos de incubação e ninfal, o desenvolvimento total e a longevidade. Dos genótipos avaliados observou-se em Coodetec 406 maior período ninfal (14,7 dias e IAC-23 a menor viabilidade de ninfas (30,7%, indicando a ocorrência de resistência do tipo antibiose contra essa mosca-branca.The silverleaf whitefly Bemisia tabaci B biotype is an important pest of many crops throughout the world. In Brazil, specifically in the Bahia State, this insect caused losses estimated to 30-70% on cotton crops. The purpose of this research was to investigate biological parameters of the silverleaf whitefly biotype B in genotype of cotton bush to verify a possible occurrence of antibiosis as resistance mechanism cotton, under greenhouse conditions. The duration of the egg and nymphal stages, and the adult longevity of B. tabaci biotype B were evaluated in the genotypes IAC-23, Coodetec 406, BRS Aroeira, Fabrika, Coodetec 407, IAC-24, Makina, IAC 20-233, Coodetec 401 and CNPA Acala I. Among those evaluated genotypes, Coodetec 406 increased the nymph stage (14.7 days and IAC-23 reduced the nymphal viability (30.7%, suggesting the occurrence of antibiosis against this whitefly.

  9. Densidades y frecuencias de liberación de Encarsia formosa (Hymenoptera: Aphelinidae sobre Trialeurodes vaporariorum (Homoptera: Aleyrodidae en tomate

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    Tello Paola

    2007-12-01

    Full Text Available

    La mosca blanca de los invernaderos, Trialeurodes vaporariorum (Westwood (Homoptera: Aleyrodidae es una de las plagas más importantes de cultivos de tomate bajo invernadero en la Sabana de Bogotá. Para su control tradicionalmente se acude a la aplicación de insecticidas. Sin embargo, también son contempladas liberaciones del parasitoide Encarsia formosa (Gahan (Hymenoptera: Aphelinidae. Para estandarizar el proceso de cría masiva de E. formosa, se evaluaron tres densidades diferentes de liberación de las avispas (6, 12 y 18 avispas/planta en tres frecuencias de liberación (1, 2 y 3 veces/semana, sobre plantas de tomate de ocho semanas de edad con tres niveles de infestación (15, 30 y 45 ninfas de mosca blanca/hoja, susceptibles de ser parasitadas. El mayor porcentaje de parasitismo (70% en ninfas de tercer instar se logró cuando se liberaron seis avispas por planta, dosificadas en tres momentos diferentes en la misma semana. El menor porcentaje de parasitismo (50%, se obtuvo cuando se realizó una sola liberación de 6, 12 o 18 avispas. Los resultados anteriores permiten concluir que se puede lograr un porcentaje de parasitismo en torno a un 70% de la infestación de mosca blanca (hasta 45 ninfas/hoja en plantas de tomate con pocas avispas de E. formosa (seis cuando se liberan en tres momentos diferentes.

  10. Effets biocides des alcaloïdes, des saponines et des flavonoïdes extraits de Capsicum frutescens L. (Solanaceae sur Bemisia tabaci (Gennadius (Homoptera : Aleyrodidae

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    Blenzar A.

    2005-01-01

    Full Text Available Biocide effects of alkaloids, saponins and flavonoids extracted from Capsicum frutescens L. (Solanaceae on Bemisia tabaci (Gennadius (Homoptera: Aleyrodidae. In an attempt to elaborate a strategy of integrated pest management on vegetable crops in Morocco, insecticidal activities of alkaloids, saponins and flavonoids extracted from Capsicum frutescens L. fruits against eggs and adults of Bemisia tabaci infesting tomato plants, Lycopersicon esculentum Mill. var. Daniella, were carried out under controlled conditions. Alkaloids, saponins and flavonoids, dissolved in ethanol at 1%, were tested at 0, 5, 10 and 20 g.l-1. The three compounds affected egg and adult survival, significantly. The mortality of embryo and adult varied according to the compound considered and for each compound according to concentration and exposure duration. For eggs, the corrected mortality varied from 35 to 59% for alkaloids, 14 to 31% for saponins and 10 to 14% for flavonoids. In adults, the mortalities were spread from 29% to 86%, 14 to 48% and 6 to 29% with alkaloids, saponins and flavonoids, respectively. Significant correlation between egg and adult mortality, due to the compounds tested, were observed. However, eggs required higher concentrations than adults; the LC50 was 13.78 vs. 6.83 g.l-1 for alkaloids, 98.63 vs. 32.28 g.l-1 for saponins and nontoxic vs. 120.65 g.l-1 for the flavonoids. Therefore, alkaloids were shown more effective against B. tabaci than saponins or flavonoids. However, the LT50 estimated for compounds, killing more than 50% of the population studied, was sufficient for viruliferous adults to inoculate TYLCV to plants before they died. The use of these compounds in integrated pest management merit further study.

  11. Gene expression profiling in the thiamethoxam resistant and susceptible B-biotype sweetpotato whitefly, Bemisia tabaci.

    Science.gov (United States)

    Xie, Wen; Yang, Xin; Wang, Shao-Ii; Wu, Qing-jun; Yang, Ni-na; Li, Ru-mei; Jiao, Xiao-guo; Pan, Hui-peng; Liu, Bai-ming; Feng, Yun-tao; Xu, Bao-yun; Zhou, Xu-guo; Zhang, You-jun

    2012-01-01

    Thiamethoxam has been used as a major insecticide to control the B-biotype sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae). Due to its excessive use, a high level of resistance to thiamethoxam has developed worldwide over the past several years. To better understand the molecular mechanisms underlying this resistance in B. tabaci, gene profiles between the thiamethoxam-resistant and thiamethoxam-susceptible strains were investigated using the suppression subtractive hybridization (SSH) library approach. A total of 72 and 52 upand down-regulated genes were obtained from the forward and reverse SSH libraries, respectively. These expressed sequence tags (ESTs) belong to several functional categories based on their gene ontology annotation. Some categories such as cell communication, response to abiotic stimulus, lipid particle, and nuclear envelope were identified only in the forward library of thiamethoxam-resistant strains. In contrast, categories such as behavior, cell proliferation, nutrient reservoir activity, sequence-specific DNA binding transcription factor activity, and signal transducer activity were identified solely in the reverse library. To study the validity of the SSH method, 16 differentially expressed genes from both forward and reverse SSH libraries were selected randomly for further analyses using quantitative realtime PCR (qRT-PCR). The qRT-PCR results were fairly consistent with the SSH results; however, only 50% of the genes showed significantly different expression profiles between the thiamethoxam-resistant and thiamethoxam-susceptible whiteflies. Among these genes, a putative NAD-dependent methanol dehydrogenase was substantially over-expressed in the thiamethoxamresistant adults compared to their susceptible counterparts. The distributed profiles show that it was highly expressed during the egg stage, and was most abundant in the abdomen of adult females.

  12. Biological traits and Life table parameters A and B biotype of Bemisia tabaci (Genn. on cotton and rapeseed

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    Mohammad Amin Samih

    2014-06-01

    Full Text Available The aim of this work was to construct life table of Bemisia tabaci (Gen. A and B (silverleaf whitefly B. argentifolii Bellows and Perring biotype (Hem.: Aleyrodidae on two host plants; cotton, (Gossypium hirsutum L. and rapeseed, (Brassica napus L.. Experiments were conducted in a growth chamber under 24 ± 2ºC, 55±3% RH and 16:8 (L:D h photoperiod on caged plants of cotton G. hirsutum L. (Varamin 76 variety and rapeseed B. napus L. (global variety. The intrinsic rate of natural increase (r m, net reproductive rate (R0 and mean generation time (T for B. tabaci A biotype was 0.1010 females per female per day, 18.4075 females per female and 30.079 day (d on cotton; 0.1286, 30.6760 and 26.77 d on rapeseed; and for B biotype (B. argentifolii those above respective parameters averaged 0.1033, 27.8426 and 32.74 d on cotton and 0.1750, 40.75 and 21.27 d on rapeseed. The total survival of A and B biotype from the egg to adult on cotton was 22.08 and 22.25, respectively. The results showed significant differences between the two biotype reared on either host plant for gross reproductive rate (GRR, net reproductive rate (R0 or NRR, intrinsic rates of increase (r m, finite rate of increase (λ, doubling time (DT and mean generation times (Tc. To obtain a better understanding of the biology of these biotypes, Stable age distribution (Cx and some other aspects of life history related to their hosts were also studied. Based upon the results, both biotypes showed a greater reproduction capacity on rapeseed than on cotton. Thus, rapeseed was more suitable host than cotton for two biotypes and this was an important factor in host plant selection for optimizing the control strategies of these major pests.

  13. Suitability changes with host leaf age for Bemisia tabaci B biotype and Trialeurodes vaporariorum.

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    Zhang, Gui-Fen; Wan, Fang-Hao

    2012-10-01

    The suitability of tomato leaves of different ages for Bemisia tabaci (Gennadius) B biotype and Trialeurodes vaporariorum (Westwood) was characterized by development time, stage-specific survival, sex ratio, longevity, and fecundity. Three categories of leaf ages were tested (young: expanding leaves biotype developed faster through the quiescent fourth nymphal instar, had higher ratio of females to males, survived longer, and produced more eggs (in the first 2 wk of adult life) than T. vaporariorum on leaves of the same age; although on young leaves, B. tabaci B biotype survivorship was lower than that of T. vaporariorum. The index of host suitability of B. tabaci B biotype was higher on mature and old leaves than on young leaves. In T. vaporariorum, no such differences were found among these three leaf ages. The results could provide some cues why B. tabaci B biotype is spreading so vigorously.

  14. First report and differential colonization of Passiflora species by the B biotype of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) in Brazil

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    Nunes, Endson S.; Vieira, Maria L.C. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ-USP), Piracicaba, SP (Brazil). Dept. de Genetica]. E-mail: esnunes@carpa.ciagri.usp.br; mlcvieir@esalq.usp.br; Brown, Judith K. [University of Arizona, Tucson, AZ (United States). Dept. of Plant Sciences]. E-mail: jbrown@Ag.arizona.edu; Moreira, Adriana G.; Rezende, Jorge A.M. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ-USP), Piracicaba, SP (Brazil). Dept. de Entomologia, Fitopatologia e Zoologia Agricola]. E-mails: agmoreir@esalq.usp.br; amrezen@esalq.usp.br; Watson, Gillian [California Dept. of Food and Agriculture, Sacramento, CA (United States)]. E-mail: gwatson@cdfa.ca.gov; Lourencao, Andre L. [Instituto Agronomico, Campinas, SP (Brazil). Centro de Pesquisa e Desenvolvimento de Fitossanidade]. E-mail: andre@iac.sp.gov.br; Piedade, Sonia M.S. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ-USP), Piracicaba, SP (Brazil). Dept. de Ciencias Exatas]. E-mail: jsoniamsp@esalq.usp.br

    2008-11-15

    This note is the first report of Bemisia tabaci (Gennadius) biotype B colonizing passionvine in Brazil. We examined the colonization of nine Passiflora species by a wild B type population under greenhouse conditions. P. amethystina Mikan was the most preferred species for oviposition and colonization, whereas P. suberosa L., P. coriacea Juss. and two commercially cultivated species, P. alata Curtis and P. edulis Sims f. flavicarpa Degener, were mostly uncolonised. P. morifolia Mast., P. cincinnata Mast., P. foetida L. and P. caerulea L. showed intermediate levels of colonization. Such differential colonization might suggest some degree of resistance by certain Passiflora species or oviposition preference by B. tabaci. (author)

  15. Migration, trapping and local dynamics of whiteflies (Homoptera: Aleyrodidae)

    DEFF Research Database (Denmark)

    Riis, Lisbeth; Nachman, Gösta

    2006-01-01

    1 The ability to quantify whitefly migration provides a tool that can contribute to an improved understanding of the epidemic development of whitefly-transmitted viruses. 2 In an attempt to develop a protocol for estimating whitefly immigration and emigration rates in an annual crop, new traps an...

  16. Insecticide resistance in Bemisia tabaci (Homoptera: Aleyrodidae) populations from Crete.

    Science.gov (United States)

    Roditakis, Emmanouil; Roditakis, Nikos E; Tsagkarakou, Anastasia

    2005-06-01

    The resistance levels to alpha-cypermethrin, bifenthrin, pirimiphos-methyl, endosulfan and imidacloprid were determined in Bemisia tabaci (Gennadius) from Crete. Five B tabaci populations collected from greenhouse and outdoor crops were bioassayed and compared with a reference susceptible strain. Bemisia tabaci collected in a floriculture greenhouse exhibited the highest resistance against all insecticides: at LC50, resistance factors were 23-fold for bifenthrin, 80-fold for alpha-cypermethrin, 18-fold for pirimiphos-methyl, 58-fold for endosulfan and 730-fold for imidacloprid. A population collected on outdoor melons was more susceptible than the reference strain against all insecticides tested, suggesting the occurrence of local highly susceptible B tabaci populations in 'refugia'. In pairwise comparisons of resistance levels, correlation was observed between the LC50 values of the pyrethroid insecticides bifenthrin and alpha-cypermethrin.

  17. Lack of fitness costs associated with pyriproxyfen resistance in the B biotype of Bemisia tabaci.

    Science.gov (United States)

    Crowder, David W; Ellers-Kirk, Christa; Tabashnik, Bruce E; Carrière, Yves

    2009-03-01

    The insect growth regulator pyriproxyfen has provided effective control of the whitefly Bemisia tabaci Gennadius in many countries. Here, whether or not fitness costs were associated with pyriproxyfen resistance in a laboratory-selected resistant strain (QC02-R) of the B biotype was determined. Mortality caused by pyriproxyfen and fitness traits over time were measured in unselected and selected hybrid strains, which were created by crossing individuals of the resistant strain with individuals of a susceptible strain. Fitness costs were not associated with resistance in QC02-R, as mortality caused by pyriproxyfen did not increase over time in unselected hybrid strains and fitness traits were similar in unselected and selected hybrid strains. Using a new method to examine the inheritance of resistance, based on data from fitness cost experiments, it was estimated that pyriproxyfen resistance is controlled by two loci in the QC02-R strain. The lack of fitness costs associated with pyriproxyfen resistance could promote the evolution of resistance in field populations with similar traits to QC02-R. 2008 Society of Chemical Industry

  18. Pyriproxyfen resistance of Bemisia tabaci (Homoptera: Aleyrodidae) biotype B: metabolic mechanism.

    Science.gov (United States)

    Ma, W; Li, X; Dennehy, T J; Lei, C; Wang, M; Degain, B A; Nichols, R L

    2010-02-01

    Juvenile hormone (JH) analog insecticides are relatively nontoxic to vertebrates and provide efficient control of key arthropod pests. One JH analog, pyriproxyfen, has provided over a decade of exceptional management of whiteflies in cotton of the southwestern United States. Thwarting resistance to pyriproxyfen in Bemisia tabaci (Gannadius) (a.k.a. Bemisia argentifolii Bellows and Perring) has been the focus of an integrated resistance management program because this insecticide was first registered for use in Arizona cotton in 1996. Resistance levels have increased slowly in field populations in recent years but have not demonstrably affected field performance of pyriproxyfen. Resistant strains have been isolated and studied in the laboratory to determine the mechanism of resistance and identify optimal strategies for controlling resistant whiteflies. Synergism bioassays showed that resistance in a laboratory-selected strain QC02-R, was partially suppressible with piperonyl butoxid (PBO) and diethyl maleate (DEM) but not with S, S, S-tributyl phosphorotrithioate (DEF). Consistent with the synergism bioassay results, enzymatic assays revealed that the enzyme activities of cytochrome P450 monooxygenases (P450) and glutathione S-transferases (GST) but not esterases were significantly higher in the pyriproxyfen-resistant QC02-R strain than in the susceptible strain. These results indicate that both P450 and GST are involved in whitefly resistance to pyriproxyfen.

  19. Diversity and Distribution of Cryptic Species of the Bemisia tabaci (Hemiptera: Aleyrodidae) complex in Pakistan.

    Science.gov (United States)

    Masood, Mariyam; Amin, Imran; Hassan, Ishtiaq; Mansoor, Shahid; Brown, Judith K; Briddon, Rob W

    2017-12-05

    Bemisia tabaci (Gennadius; Hempitera: Aleyrodidae) is considered to be a cryptic (sibling) species complex, the members of which exhibit morphological invariability while being genetically and behaviorally distinct. Members of the complex are agricultural pests that cause direct damage by feeding on plants, and indirectly by transmitting viruses that cause diseases leading to reduced crop yield and quality. In Pakistan, cotton leaf curl disease, caused by multiple begomovirus species, is the most economically important viral disease of cotton. In the study outlined here, the diversity and geographic distribution of B. tabaci cryptic species was investigated by analyzing a taxonomically informative fragment of the mitochondrial cytochrome c oxidase 1 gene (mtCOI-3'). The mtCOI-3' sequence was determined for 285 adult whiteflies and found to represent six cryptic species, the most numerous being Asia II-1 and Middle East Asia Minor 1 (MEAM-1), the later also referred to as the B-biotype, which was previously thought to be confined to Sindh province but herein, was also found to be present in the Punjab province. The endemic Asia I was restricted to Sindh province, while an individual in the Asia II-8 was identified in Pakistan for the first time. Also for the first time, samples were collected from northwestern Pakistan and Asia II-1 was identified. Results indicate that in Pakistan the overall diversity of B. tabaci cryptic species is high and, based on comparisons with findings from previous studies, the distribution is dynamic. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  20. Biology of Bemisia tabaci (Genn. B-biotype and parasitism by Encarsia formosa (Gahan on collard, soybean and tomato plants Aspectos biológicos de Bemisia tabaci (Genn. biótipo B e parasitismo por Encarsia formosa (Gahan em couve, soja e tomateiro

    Directory of Open Access Journals (Sweden)

    Karina Manami Takahashi

    2008-12-01

    Full Text Available The silverleaf whitefly Bemisia tabaci (Genn. B-biotype (= B. argentifolii (Hemiptera: Aleyrodidae is a polyphagous insect attacking many plant species of economic importance. A comparison study was conducted on the duration of the egg-to-adult period, and the percentage of hatching eggs of Bemisia tabaci (Genn. B-biotype on collard (Brassica oleracea L. var. acephala D.C., soybean(Glycine max (L. Merr. and tomato (Lycopersicon esculentum Mill. plants, as well as the egg-to-adult period of Encarsia formosa (Gahan on the 1st, 2nd, 3rd and 4th whitefly nymphal instars on these three plant species. The experiments were conducted in a laboratory (25ºC, 70 ± 10% RH, 14-hour photophase. The duration of the egg-to-adult period of B. tabaci was 19.8 days on collard, 21.2 days on soybean and 22.0 days on tomato. The number of hatched eggs was higher on collard when compared to soybean and tomato plants. Concerning E. formosa regardless of plant species, the duration for the egg-to-adult period was shorter for the 3rd and 4th instar nymphs as compared with the other instars.A mosca branca Bemisia tabaci (Genn. biótipo B é uma praga polífaga que ataca muitas culturas de importância econômica. O controle químico pode causar problemas como o aparecimento de resistência nesse inseto, resíduos nos produtos das culturas, ou mesmo poluição ambiental. Um método alternativo seria o controle biológico, com o parasitóide Encarsia formosa (Gahan, o mais usado contra moscas brancas a nível mundial. Avaliaram-se o tempo de desenvolvimento de ovo a adulto e a porcentagem de ninfas eclodidas de B. tabaci (Genn. biótipo B em couve (Brassica oleracea L. var. acephala D.C., soja (Glycine max (L. Merr. e tomateiro (Lycopersicon esculentum Mill., bem como o desenvolvimento de ovo a adulto de E. formosa em ninfas de 1º, 2º, 3º e 4º ínstares dessa mosca-branca nessas três espécies vegetais. Os experimentos foram desenvolvidos em laboratório, a 25ºC, 70

  1. Dinâmica populacional de Bemisia tabaci biótipo B em tomate monocultivo e consorciado com coentro sob cultivo orgânico e convencional Population dynamic of Benisua tabaci B biotype in monoculture tomato crop and consortium with coriander in organic and conventional crop system

    Directory of Open Access Journals (Sweden)

    Pedro HB Togni

    2009-06-01

    Full Text Available A mosca-branca Bemisia tabaci Biótipo B (Hemiptera: Aleyrodidae, é um herbívoro de difícil controle devido à alta plasticidade genotípica da espécie. No tomateiro pode causar danos severos principalmente pela transmissão de diversas viroses. O manejo do sistema de produção e o consórcio de culturas podem ter um efeito direto nas populações desse herbívoro, sem que seja necessária a aplicação de inseticidas. Avaliou-se a influência dos sistemas de produção orgânico e convencional e o consórcio tomate-coentro na dinâmica populacional da mosca-branca no campo experimental da Embrapa Hortaliças, de maio a setembro/06. O monitoramento dos adultos da mosca-branca e de seus inimigos naturais foi realizado utilizando-se armadilhas adesivas amarelas fixadas nas bordas e no interior das parcelas experimentais e a amostragem de ninfas foi realizada por observação direta das folhas de tomate no campo. Embora as populações ao redor dos diferentes tratamentos fossem equivalentes, a abundância de adultos de mosca-branca foi significativamente menor nas parcelas de tomate consorciado com coentro, tanto no sistema convencional como orgânico. Apenas o consórcio tomatecoentro em sistema orgânico apresentou redução significativa na quantidade de ninfas por planta em relação aos demais tratamentos. Os inimigos naturais foram significativamente mais abundantes em sistema orgânico e foi verificada uma correlação negativa da abundância dos inimigos naturais e a quantidade de ninfas por planta. A associação tomate-coentro e o manejo orgânico do agroecossistema favoreceram ao controle biológico natural da mosca-branca.Due to its high genotypic plasticity, the control of the silverleaf whitefly Bemisia tabaci B biotype (Hemiptera: Aleyrodidae, is difficult. This insect may cause severe damage to the tomato crop as a vector of several viruses. The management of the production system and the consortium with other crops may have a

  2. Biología de Eretmocerus mundus (Hymenoptera: Aphelinidae, parasitoide del complejo Bemisia tabaci (Homoptera: Aleyrodidae, en condiciones de laboratorio Biology of Eretmocerus mundus (Hymenoptera: Aphelinidae, parasitoid of Bemisia tabaci complex (Homoptera: Aleyrodidae under laboratory conditions

    Directory of Open Access Journals (Sweden)

    Yerlin Chacón Castro

    2010-06-01

    Full Text Available La estimación de los atributos biológicos de un enemigo natural, previa a su empleo en el campo, constituye un aspecto de importancia en todo proyecto de control biológico. El objetivo de este trabajo fue evaluar los principales parámetros biológicos de Eretmocerus mundus Mercet, parasitoide de Bemisia tabaci (Gennadius, bajo condiciones de laboratorio.La emergencia del adulto, longevidad y fecundidad de la hembra, proporción sexual de la descendencia, tasa intrínseca de crecimiento poblacional (r m, tasa neta de reproducción (Ro y tiempo generacional (T; se estimaron mediante la técnica de tabla de vida y fecundidad, utilizando el pimiento (Capsicum annuum L. y el tomate (Solanum lycopersicum L. como plantas hospederas. Los resultados obtenidos en pimiento y tomate fueron respectivamente: supervivencia pupal: 86.86 ± 1.94 y 83,45 ± 2,13%; longevidad de la hembra: 18,19 ± 1,61 y 17,00 ± 0,92 días; proporción sexual: 0,34 ± 0,06 y 0,47 ± 0,05 hembras/(machos + hembras; l x50: 21 y 18 días; r m: 0,226 ± 0,061 y 0,228 ± 0,057 ninfas parasitadas/hembra/día; Ro: 189,71 ± 24,25 y 154,65 ± 17,58 ninfas parasitadas/hembra; T: 25,88 ± 0,42 y 24,03 ± 0,34 días. Los resultados obtenidos son una contribución al conocimiento de la población local del parasitoide y su posible papel como agente de control biológico de B. tabaci.The estimation of biological attributes of natural enemies prior to its use in the field is an important tool in a biological control program. The objective of the present paper was to evaluate the main biological parameters of Eretmocerus mundus Mercet, a parasitoid of Bemisia tabaci (Gennadius, under controlled laboratory conditions. Parasitoid survival, female longevity, fecundity, sex rate, intrinsic rate of natural increase (r m, net reproductive rate (Ro and generational time (T were studied using life tables, with pepper (Capsicum annuum L. and tomato (Solanum lycopersicum L. as host plants. Results obtained on pepper and tomato, respectively, were: pupal survival: 86.86 ± 1.94 and 83,45 ± 2,13%; female longevity: 18,19 ± 1,61 and 17,00 ± 0,92 days; sex rate: 0,34 ± 0,06 and 0,47 ± 0,05 female/(male + female; l x50: 21 and 18 days; r m: 0,226 ± 0,061 and 0,228 ± 0,057 parasitized nymphs/female/day; Ro: 189,71 ± 24,25 and 154,65 ± 17,58 parasitized nymphs/female; T: 25,88 ± 0,42 and 24,03 ± 0,34 days. Results lead to a better understanding of the local population of this parasitoid and its potential role as a biological control agent of B. tabaci.

  3. Biología de Eretmocerus mundus (Hymenoptera: Aphelinidae), parasitoide del complejo Bemisia tabaci (Homoptera: Aleyrodidae), en condiciones de laboratorio Biology of Eretmocerus mundus (Hymenoptera: Aphelinidae), parasitoid of Bemisia tabaci complex (Homoptera: Aleyrodidae) under laboratory conditions

    OpenAIRE

    Yerlin Chacón Castro; Silvia N. López

    2010-01-01

    La estimación de los atributos biológicos de un enemigo natural, previa a su empleo en el campo, constituye un aspecto de importancia en todo proyecto de control biológico. El objetivo de este trabajo fue evaluar los principales parámetros biológicos de Eretmocerus mundus Mercet, parasitoide de Bemisia tabaci (Gennadius), bajo condiciones de laboratorio.La emergencia del adulto, longevidad y fecundidad de la hembra, proporción sexual de la descendencia, tasa intrínseca de crecimiento poblacio...

  4. Antifeedant activity of botanical crude extracts and their fractions on Bemisia tabaci (Homoptera: Aleyrodidae adults: I. Gliricidia sepium (Fabaceae

    Directory of Open Access Journals (Sweden)

    Guillermo Flores

    2008-12-01

    Full Text Available Bemisia tabaci is an important virus vector on a number of crops worldwide. Therefore, a preventive approach to deal with viral epidemics may be the deployment of repellents or phagodeterrents at earlier stages of plant development (critical period. Thus, the crude extract and four fractions thereof (water, water:methanol, methanol, and diethyl ether of mother-of-cocoa (Gliricidia sepium, Fabaceae were tested for phagodeterrence to B. tabaci adults under greenhouse conditions, on tomato plants, in Costa Rica. Both restricted-choice and unrestricted-choice experiments showed that the crude extract and some fractions exerted such effect on the insect. In the former (in sleeve cages, three fractions caused deterrence at doses as low as 0.1% (methanol, 0.5% (water:methanol and 1.5% (diethyl ether. However, in the latter (plants exposed in a greenhouse no one of the fractions performed well, suggesting that the deterrent principles somehow decomposed under the experimental conditions. Rev. Biol. Trop. 56 (4: 2099-2113. Epub 2008 December 12.Mundialmente, Bemisia tabaci es un importante vector de virus en numerosos cultivos. Por tanto, un enfoque preventivo para enfrentar las epidemias virales podría ser el empleo de sustancias repelentes o fagodisuasivas en las etapas tempranas del desarrollo de las plantas (período crítico. Así, tanto el extracto crudo como cuatro fracciones (agua, agua:metanol, metanol y éter dietílico del madero negro (Gliricidia sepium, Fabaceae fueron evaluadas en cuanto a su actividad fagodisuasiva sobre los adultos de B. tabaci en condiciones de invernadero, utilizando plantas de tomate, en Turrialba, Costa Rica. Tanto los experimentos de escogencia restringida como los de escogencia irrestricta revelaron que el extracto crudo y algunas fracciones mostraron dicha actividad. En los primeros experimentos (en jaulas de manga, tres fracciones causaron fagodisuasión a dosis tan bajas como 0.1% (metanol, 0.5% (agua:metanol y 1.5% (éter dietílico. Sin embargo, en los segundos (plantas expuestas dentro de un invernadero ninguna de las fracciones lo hizo, lo cual sugiere que los principios fagodisuasivos perdieron su actividad en esas condiciones experimentales.

  5. Antifeedant activity of botanical crude extracts and their fractions on Bemisia tabaci (Homoptera: Aleyrodidae adults: II. Sechium pittieri (Cucurbitaceae

    Directory of Open Access Journals (Sweden)

    Guillermo Flores

    2008-12-01

    Full Text Available Bemisia tabaci is a key pest of vegetables and other crops worldwide, but it is a particularly serious problem in the tropics, due to its ability to transmit several types of viruses, especially begomoviruses (Geminiviridae. Therefore, a preventive approach to deal with viral epidemics may be the deployment of repellents or phagodeterrents at earlier stages of plant development (critical period. Thus, the crude extract and four fractions thereof (water, water: methanol, methanol, and diethyl ether of wild "tacaco" (Sechium pittieri, Cucurbitaceae, were tested for phagodeterrence to B. tabaci adults under greenhouse conditions, on tomato plants, in Costa Rica. Both restricted-choice and unrestricted-choice experiments showed that the crude extract as well as some fractions exert such effect on the insect. In the former (in sleeve cages, fractions caused deterrence at doses as low as 0.1% (ether and 0.5% (water and water: methanol, with the methanol fraction showing no activity. However, in the latter (plants exposed in a greenhouse no one of the fractions performed well, suggesting that the deterrent principles somehow decomposed under the experimental conditions. Rev. Biol. Trop. 56 (4: 2115-2129. Epub 2008 December 12.Bemisia tabaci es una plaga clave de hortalizas y otros cultivos, mundialmente, y representa un problema particularmente serio en los trópicos, debido a su habilidad para transmitir varios tipos de virus, especialmente begomovirus (Geminiviridae. Por tanto, un enfoque preventivo para enfrentar las epidemias virales podría consistir en la utilización de sustancias repelentes o disuasivas en las eta-pas tempranas del desarrollo de la planta (período crítico. Así, el extracto crudo y cuatro fracciones (agua, agua: metanol, metanol, y éter dietílico de tacaco cimarrón (Sechium pittieri, Cucurbitaceae, fueron evaluadas por su posible actividad fagodisuasiva sobre B. tabaci en un invernadero, utilizando plantas de tomate, en Turrialba, Costa Rica. Tanto los experimentos de escogencia restringida como los de escogencia irrestricta mostraron dicha actividad en el extracto crudo y en algunas de sus fracciones. En el primer tipo de experimento (en jaulas de manga, las fracciones causaron fagodisuasión a dosis tan bajas como 0.1% (éter dietílico y 0.5% (agua y agua: metanol, mientras que la fracción metanólica no la causó. Sin embargo, en los otros experimentos (plantas expuestas a B. tabaci dentro de un invernadero ninguna de las fracciones funcionó bien, lo cual sugiere que los principios disuasivos se disiparon bajo esas condiciones experimentales.

  6. Biología de Eretmocerus mundus (Hymenoptera: Aphelinidae, parasitoide del complejo Bemisia tabaci (Homoptera: Aleyrodidae, en condiciones de laboratorio

    Directory of Open Access Journals (Sweden)

    Yerlin CHACÓN CASTRO

    2010-01-01

    Full Text Available La estimación de los atributos biológicos de un enemigo natural, previa a su empleo en el campo, constituye un aspecto de importancia en todo proyecto de control biológico. El objetivo de este trabajo fue evaluar los principales parámetros biológicos de Eretmocerus mundus Mercet, parasitoide de Bemisia tabaci (Gennadius, bajo condiciones de laboratorio. La emergencia del adulto, longevidad y fecundidad de la hembra, proporción sexual de la descendencia, tasa intrínseca de crecimiento poblacional (r m , tasa neta de reproducción (R o y tiempo generacional (T; se estimaron mediante la técnica de tabla de vida y fecundidad, utilizando el pimiento ( Capsicum annuum L. y el tomate ( Solanum lycopersicum L. como plantas hospederas. Los resultados obtenidos en pimiento y tomate fueron respectivamente: supervivencia pupal: 86.86 ± 1.94 y 83,45 ± 2,13%; longevidad de la hembra: 18,19 ± 1,61 y 17,00 ± 0,92 días; proporción sexual: 0,34 ± 0,06 y 0,47 ± 0,05 hembras/(machos + hembras; l x50 : 21 y 18 días; r m : 0,226 ± 0,061 y 0,228 ± 0,057 ninfas parasitadas/hembra/día; Ro: 189,71 ± 24,25 y 154,65 ± 17,58 ninfas parasitadas/hembra; T: 25,88 ± 0,42 y 24,03 ± 0,34 días. Los resultados obtenidos son una contribución al conocimiento de la población local del parasitoide y su posible papel como agente de control biológico de B. tabaci.

  7. Biología de Eretmocerus mundus (Hymenoptera: Aphelinidae), parasitoide del complejo Bemisia tabaci (Homoptera: Aleyrodidae), en condiciones de laboratorio

    OpenAIRE

    Chacón Castro, Yerlin; Silvia N. López

    2010-01-01

    La estimación de los atributos biológicos de un enemigo natural, previa a su empleo en el campo, constituye un aspecto de importancia en todo proyecto de control biológico. El objetivo de este trabajo fue evaluar los principales parámetros biológicos de Eretmocerus mundus Mercet, parasitoide de Bemisia tabaci (Gennadius), bajo condiciones de laboratorio. La emergencia del adulto, longevidad y fecundidad de la hembra, proporción sexual de la descendencia, tasa intrínseca de crecimiento poblaci...

  8. Status Of Cotton Aphid, Aphis gssypiiHomoptera ...

    African Journals Online (AJOL)

    Electrophoretic banding patterns and quantitative analysis of carboxylesterases from cotton aphid, Aphis gossypii Glover (Homoptera: Aphididae) populations infesting vegetables in southern Ghana revealed a nation-wide build-up and spread of resistant genes in most vegetable growing areas. Most aphid populations ...

  9. Survey of Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae biotypes in Brazil using RAPD markers

    Directory of Open Access Journals (Sweden)

    L.H.C. Lima

    2000-12-01

    Full Text Available In 1991, the poinsettia strain, silverleaf whitefly or B biotype of Bemisia tabaci was detected in Brazil. This variant is a far more serious agricultural pest than the previously prevalent non-B (BR biotype. The correct identification of B. tabaci is problematic since it is highly polymorphic with extreme plasticity in key morphological characters that vary according to the host. RAPD-PCR was used to survey the B biotype and other biotypes of B. tabaci in Brazil. Whiteflies were collected from cultivated plants and weeds from 57 different localities and on 27 distinct crops. RAPD analyses using two selected 10-mer primers reliably identified the BR biotype and the B biotype of B. tabaci and also differentiated other whitefly species. The presence of the B biotype was confirmed in 20 Brazilian states. The BR and B biotypes of B. tabaci were found to coexist in the whitefly populations of three different localities: Jaboticabal, SP; Rondonópolis and Cuiabá, MT, and Goiânia, GO.Em 1991, um novo biótipo de Bemisia tabaci denominado de raça B, mosca branca da poinsétia ou mosca da folha prateada foi detectado no Brasil. Esta praga trouxe muitos prejuízos e danos à agricultura nacional, por ser mais agressiva do que a existente anteriormente, conhecida como B. tabaci ou B. tabaci biótipo BR (não B. A relação taxonômica entre B. tabaci e B. tabaci biótipo B não é clara e não existem evidências morfológicas consistentes que possam distinguir esses dois biótipos. RAPD-PCR tem sido utilizada para identificação de biótipos presentes nas populações, utilizando-se, como padrões de referência, adultos de Bemisia tabaci das raças A e B provenientes dos Estados Unidos. As coletas de mosca branca foram feitas em 27 culturas e plantas daninhas em 57 localidades do país. As populações foram então analisadas, observando-se que a população predominante em 20 estados brasileiros é de B. tabaci biótipo B. Os biótipos BR e B foram

  10. Effects of a foliar neem formulation on colonization and mortality of whiteflies (Hemiptera: Aleyrodidae) on collard plants

    Science.gov (United States)

    A study was conducted to determine the effects of foliar sprays of a selected neem (Azadirachta indica A. Juss) product (GOS Neem 7-Way) on colonization and development by the Middle-East Asia Minor-1 (= B-biotype sweetpotato whitefly) Bemisia tabaci (Gennadius) on collard (Brassica oleracea variety...

  11. Untersuchung zum Einsatz natürlicher und synthetischer Insektizide und zur Parasitierung von Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) im Tomatenanbau in Panama

    OpenAIRE

    Bernal Vega, Juan A.

    2001-01-01

    Die Wirkung von Niemprodukten und Confidor® 70 WG auf Trialeurodes vaporariorum Westwood an verschiedenen Wirtspflanzen unter Laborbedingungen Der Wirkungsgrad von Niemprodukten und Confidor® 70 WG wurde unter Laborbedingungen auf die Populationsdichte von Trialeurodes vaporariorum Westwood (Eier, Larven und Adulte) an Tomaten-, und Kohlpflanzen bestimmt. Es wurde auch die Kompatibilität der obengenannten Produkte bei gleichzeitiger Freilassung von Encarsia formosa Gahan (Hymenop...

  12. Monitoreo de estados inmaduros de la mosca blanca [Trialeurodes vaporariorum (Westwood) (Homoptera-Aleyrodidae)] reinfestando cultivo de tomate bajo invernadero en el período estival

    OpenAIRE

    Sánchez, Daniel E.; Scotta, Roberto R.; Arregui, María Cristina

    2002-01-01

    En los cultivos de tomate en invernadero, la mosca blanca de los invernaderos (Trialeurodes vaporariorum) se ha convertido en plaga clave, tanto por los daños que ocasiona, como por la dificultad para su control con métodos químicos. El objetivo de este trabajo fue determinar la distribución de los estados inmaduros de mosca blanca reinfestando la planta de tomate cultivada bajo invernadero, las áreas de concentración en el cultivo y detectar si existía en el período estival una relación entr...

  13. Estudios sobre la transmisión por "moscas blancas" (Homoptera: aleyrodidae de virus asociados con el "cuero de sapo" en yuca (Manihot esculenta Crantz

    Directory of Open Access Journals (Sweden)

    Angel S. Juan C.

    1987-12-01

    Full Text Available Estudios realizados en la zona endémica al "cuero de sapo" (Quilcacé, Cauca, encaminados a determinar la presencia de vectores de la enfermedad mostraron la existencia de dos virus asociados con "moscas blancas". El primero denominado "agente mosaico" fue transmitido por Bemisia tuberculata, el segundo asintomático, por Aleurotrachelus socialis. El 3.3% de la población de B. tuberculata utilizada transmitió el "agente mosaico" al clón M Col 2063 (Secundina y no a M Col 113: el 2.4 % de A. socialis transmitió el asintomático al clón Secundina y el 4.7% a M Col 113. El "agente mosaico", no fue identificado, pero si se demostró que el asintomático presente era CsXV; este sería el primer registro de un potexvirus transmitido por "moscas blancas". El papel de los dos virus en la etiología del “cuero de sapo” continúa en estudio.Whiteflies collected from a frogskin infested field in Quilcacé (Cauca were caged individually on M Col 2063 (Secundina and M Col 113 plants. It was possible to identify the species (Aleurotrachelus socialis, Trialeurodes variabilis and Bemisia tuberculata from pupae present on over 50% of the plants. A. socialis was found most f frequently and B. tuberculata the least com mom of the species. A. socialis was associated with the transmission of both CsXV and a serologically related strain, identified on the basis of symptoms produced on Nicotiana bentamiana, B. tuberculata was associated with the transmission of a mosaic agent to Secundina. The identify of the mosaic agent is unknown.

  14. Estudios sobre la transmisión por "moscas blancas" (homoptera: aleyrodidae) de virus asociados con el "cuero de sapo" en yuca (manihot esculenta crantz)

    OpenAIRE

    Angel S. Juan C.; Pineda L. Benjamín; Nolt Barry L.

    2010-01-01

    Estudios realizados en la zona endémica al "cuero de sapo" (Quilcacé, Cauca), encaminados a determinar la presencia de vectores de la enfermedad mostraron la existencia de dos virus asociados con "moscas blancas". El primero denominado "agente mosaico" fue transmitido por Bemisia tuberculata, el segundo asintomático, por Aleurotrachelus socialis. El 3.3% de la población de B. tuberculata utilizada transmitió el "agente mosaico" al clón M Col 2063 (Secundina) y no a M Col 113: el 2.4 % de A. s...

  15. Effects of double-stranded RNA on virulence of Paecilomyces fumosoroseus (Deuteromycotina: Hyphomycetes against the silverleaf whitefly, Bemisia tabaci strain B (Homoptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Andréia Cristiane Souza Azevedo

    2000-03-01

    Full Text Available Bands of double-stranded RNA (dsRNA were detected in three out of twelve isolates of Paecilomyces fumosoroseus. Identity of these bands was confirmed by RNAse, DNAse and S1 nuclease treatments. The cure of dsRNA for one isolate (P92 was successfully carried out for a single conidium subculture. Isogenic strains, with or without dsRNA, were submitted to virulence tests against the whitefly Bemisia tabaci strain B. In contrast to findings for some phytopathogenic fungi, these dsRNA fragments did not cause hypovirulence in P. fumosoroseus.Bandas de dsRNA foram detectadas em três dos doze isolados de Paecilomyces fumosoroseus. A identidade destas bandas foi provada através de tratamentos com RNAse, DNAse e S1 nuclease. A cura do dsRNA para um dos isolados (P92 foi obtida através do isolamento de colônias monospóricas. Linhagens isogênicas, com e sem dsRNA, foram submetidas ao teste de virulência contra a mosca branca Bemisia tabaci biotipo B. Ao contrário do que ocorre para vários fungos fitopatogênicos, os fragmentos de dsRNA não causaram hipovirulência em P. fumosoroseus.

  16. [Phagodeterrent activity of the plants Tithonia diversifolia and Montanoa hibiscifolia (Asteraceae) on adults of the pest insect Bemisia tabaci (Homoptera: Aleyrodidae)].

    Science.gov (United States)

    Bagnarello, Gina; Hilje, Luko; Bagnarello, Vanessa; Cartín, Victor; Calvo, Marco

    2009-12-01

    Bemisia tabaci (Gennadius) is a polyphagous, cosmopolitan and worldwide relevant pest, mainly acting as a virus vector on many crops. A sound preventive approach to deal with it would be the application of repellent or deterrent substances hopefully present in tropical plants, which in turn may contribute to take advantage of the remarkable rich Mesoamerican biodiversity. Therefore, extracts of two wild plants belonging to family Asteraceae, titonia (Tithonia diversifolia) and "tora" (Montanoa hibiscifolia), were tested for phagodeterrence to B. tabaci adults. The crude leaf extract of each one, as well as four fractions thereof (hexane, dichlorometane, ethyl acetate, and methanol) were tested under greenhouse conditions; in addition, the extracts were submitted to a phytochemical screening to determine possible metabolites causing phagodeterrence. Both restricted-choice and unrestricted-choice experiments were conducted. In the former ones, each fraction was tested at four doses (0.1, 0.5, 1.0 and 1.5% v/v), which were compared with four control treatments: distilled water, endosulfan, an agricultural oil (Aceite Agricola 81 SC), and the emulsifier Citowett. Tomato plants were sprayed and placed inside sleeve cages, where 50 B. tabaci adults were released. The criterion to appraise phagodeterrence was the number of landed adults on plants at 48h. For the unrestricted-choice experiments, only the two highest doses (1.0 and 1.5%) of the crude extracts of each species were tested, and compared to distilled water and the agricultural oil. The titonia and "tora" crude extracts caused phagodeterrence, and for both plant species the methanol fraction stood out. Results suggest that metabolites causing phagodeterrence are several sesquiterpenic lactones, polyphenolic compounds (flavonoids and tannins) and saponins.

  17. Insecticide resistance in Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) and Anopheles gambiae Giles (Diptera: Culicidae) could compromise the sustainability of malaria vector control strategies in West Africa.

    Science.gov (United States)

    Gnankiné, Olivier; Bassolé, Imael H N; Chandre, Fabrice; Glitho, Isabelle; Akogbeto, Martin; Dabiré, Roch K; Martin, Thibaud

    2013-10-01

    Insecticides from the organophosphate (OP) and pyrethroid (PY) chemical families, have respectively, been in use for 50 and 30 years in West Africa, mainly against agricultural pests, but also against vectors of human disease. The selection pressure, with practically the same molecules year after year (mainly on cotton), has caused insecticide resistance in pest populations such as Bemisia tabaci, vector of harmful phytoviruses on vegetables. The evolution toward insecticide resistance in malaria vectors such as Anopheles gambiae sensus lato (s.l.) is probably related to the current use of these insecticides in agriculture. Thus, successful pest and vector control in West Africa requires an investigation of insect susceptibility, in relation to the identification of species and sub species, such as molecular forms or biotypes. Identification of knock down resistance (kdr) and acetylcholinesterase gene (Ace1) mutations modifying insecticide targets in individual insects and measure of enzymes activity typically involved in insecticide metabolism (oxidase, esterase and glutathion-S-transferase) are indispensable in understanding the mechanisms of resistance. Insecticide resistance is a good example in which genotype-phenotype links have been made successfully. Insecticides used in agriculture continue to select new resistant populations of B. tabaci that could be from different biotype vectors of plant viruses. As well, the evolution of insecticide resistance in An. gambiae threatens the management of malaria vectors in West Africa. It raises the question of priority in the use of insecticides in health and/or agriculture, and more generally, the question of sustainability of crop protection and vector control strategies in the region. Here, we review the susceptibility tests, biochemical and molecular assays data for B. tabaci, a major pest in cotton and vegetable crops, and An. gambiae, main vector of malaria. The data reviewed was collected in Benin and Burkina Faso between 2008 and 2010 under the Corus 6015 research program. This review aims to show: (i) the insecticide resistance in B. tabaci as well as in An. gambiae; and (ii) due to this, the impact of selection of resistant populations on malaria vector control strategies. Some measures that could be beneficial for crop protection and vector control strategies in West Africa are proposed. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Biology, ecology, and control of the Ficus whitefly, Singhiella simplex (Hemiptera: Aleyrodidae)

    Science.gov (United States)

    The Ficus whitefly, Singhiella simplex (Singh) (Hemiptera: Aleyrodidae), is an economic pest of Ficus plant species in India, Burma and China. Severe infestations result in leaf dropping or shedding and defoliation. Since its initial US report in south Florida in 2007, the whitefly has expanded its ...

  19. Life table analysis and development of Singhiella simplex (Hemiptera:Aleyrodidae) under different constant temperatures

    Science.gov (United States)

    The ficus whitefly, Singhiella simplex (Singh) (Hemiptera: Aleyrodidae), is a newly-invasive pest of ficus plants in the United States. Very little is known about its biology and life history. Here, we studied development and reproduction at 15, 20, 25, 27, 30 and 35°C. No immatures survived the 35°...

  20. On a false and a genuine Caddis-fly from Burmese amber (Insecta: Trichoptera, Homoptera)

    NARCIS (Netherlands)

    Botosaneanu, L.

    1981-01-01

    Two specimens of fossil insects in amber from Burma (burmite), belonging to the B.M. (N.H.), London, were studied. The first one, described by Cockerell (1917) as a new genus and species of Trichoptera (Plecophlebus nebulosus) belongs, in fact, to the Homoptera Auchenorhyncha. The second one is the

  1. Efeito de extratos aquosos de meliáceas sobre Bemisia tabaci biótipo B em tomateiro Effect of aqueous extracts of meliaceous plants on Bemisia tabaci B biotype on tomato plants

    Directory of Open Access Journals (Sweden)

    ANTONIO PANCRÁCIO DE SOUZA

    2000-01-01

    Full Text Available Comparou-se a bioatividade de extratos aquosos a 3% (p/v de três meliáceas, Melia azedarach L. (frutos verdes, Trichilia pallida Swartz (ramos e Azadirachta indica A. Juss (sementes, em relação à mosca branca Bemisia tabaci (Gennadius biótipo B, criada em tomateiro. No primeiro experimento os extratos foram aplicados sobre ovos e sobre ninfas com três dias de idade, avaliando-se a mortalidade e a duração das fases de ovo e de ninfa. No segundo experimento os extratos foram aplicados apenas sobre as ninfas, avaliando-se a mortalidade nessa fase e a longevidade e fecundidade dos adultos. Em relação à fase de ovo, o extrato de T. pallida foi o que provocou maior mortalidade, seguindo-se os de A. indica e M. azedarach. A maior mortalidade ninfal foi constatada com o extrato de A. indica, seguindo-se os de T. pallida e M. azedarach. Nenhum dos extratos afetou a duração das fases de ovo e de ninfa, assim como a longevidade e fecundidade.The objective of this research was to compare the effect of aqueous extracts of fresh fruits of Melia azedarach L., twigs of Trichilia pallida Swartz and seeds of zadirachta indica A. Juss, on eggs and nymphs of silverleaf whitefly Bemisia tabaci (Gennadius B biotype reared on tomato plants. The extracts were tested at a concentration of 3%. In the first experiment, the extracts were applied on eggs and 3-day-old nymphs. Records were taken on mortality, duration of egg and nymphal stages. In the second experiment the extracts were applied on 3-day-old nymphs and records were taken on nymphal mortality, adult longevity and fecundity. The extracts of T. pallida were the most effective on eggs, followed by A. indica and M. azedarach. The extracts of A. indica were the most effective on nymphs followed by T. pallida and M. azedarach. In both experiments, the duration of egg and nymph stages, longevity and fecundity were not affected by the extracts.

  2. Potencial de Chrysoperla externa (Hagen no controle de Bemisia tabaci (Gennadius biótipo B em tomateiro = Potential of Chrysoperla externa (Hagen at B-biotype Bemisia tabaci (Gennadius nymphs control in tomato plants

    Directory of Open Access Journals (Sweden)

    André Luiz Furtado Braga

    2007-01-01

    , with 3 x 4factorial scheme and eight repetitions. The C. externa larvae released in the first day after whitefly nymph eclosion were most efficient in reducing prey population at 10 larvae per plant, ensuring roughly 50% pest control. When released on the eight day after nymph eclosion, at densities of five and ten C. externa larvae per plant, a pest density reduction of approximately 40% was observed. Therefore, releasing C. externa larvae on tomato plantskept individually in cages is efficient to control B-biotype B. tabaci.

  3. Presencia de Clitostethus arcuatus (Coleoptera: Coccinellidae sobre olivos infestados con Siphoninus phillyreae (Hemiptera: Aleyrodidae en Argentina

    Directory of Open Access Journals (Sweden)

    María L. GASPARINI

    2007-01-01

    Full Text Available Se informa acerca del hallazgo de Clitostethus arcuatus (Rossi (Coleptera: Coccinellidae, Scymninae en plantas de olivo infestados con Siphoninus phillyreae (Haliday (Hemiptera: Aleyrodidae. El material se recolectó en plantaciones de olivo de los departamentos Junín, San Martín, Rivadavia y Maipú (Mendoza, Argentina durante los monitoreos de identificación de enemigos naturales de la «mosca blanca del fresno», Siphoninus phillyreae.

  4. Mitigating trans-boundary movement of Bemisia tabaci (Hemiptera: Aleyrodidae) on Mentha sp. by pre-shipping treaments of biopesticides

    Science.gov (United States)

    Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a major pest of several important crops including vegetables, cereals, fruits, and ornamentals grown worldwide. One important mode of its dispersal is through the trans-boundary movement of infested plant materials. In order to prevent the sprea...

  5. Neue mediterrane Zikadenarten der Gattungen Hysteropterum Amyot & Serville, 1843, Macropsidius Ribaut, 1952, und Chlorita Fieber, 1872 (Homoptera, Auchenorrhyncha)

    NARCIS (Netherlands)

    Dlabola, Jirí

    1975-01-01

    Some mediterranean species of Homoptera, Auchenorrhyncha are described and figured. Hysteropterum duffelsi n. sp. and H. gravesteini n. sp. (Issidae) are described respectively from Cyprus and Mallorca. In the genus Macropsidius (Cicadellidae), M. hispanus Dlabola, 1963 falls as a junior synonym of

  6. Presencia de Clitostethus arcuatus (Coleoptera: Coccinellidae sobre olivos infestados con Siphoninus phillyreae (Hemiptera: Aleyrodidae en Argentina On the presence of Clitostethus arcuatus (Coleoptera: Coccinellidae on olive trees infested with Siphoninus phillyreae (Hemiptera: Aleyrodidae in Argentina

    Directory of Open Access Journals (Sweden)

    María L. Gasparini

    2007-07-01

    Full Text Available Se informa acerca del hallazgo de Clitostethus arcuatus (Rossi (Coleptera: Coccinellidae, Scymninae en plantas de olivo infestados con Siphoninus phillyreae (Haliday (Hemiptera: Aleyrodidae. El material se recolectó en plantaciones de olivo de los departamentos Junín, San Martín, Rivadavia y Maipú (Mendoza, Argentina durante los monitoreos de identificación de enemigos naturales de la «mosca blanca del fresno», Siphoninus phillyreae.The presence of Clitostethus arcuatus (Rossi (Coleoptera: Coccinellidae,Scymninae on olive trees infested with Siphoninus phillyreae (Haliday (Hemiptera: Aleyrodidae, is reported. Specimens were collected during a survey on natural enemies of «ash whitefly», Siphoninus phillyreae, carried out in olive plantations of Junín, San Martín, Rivadavia and Maipú (Mendoza, Argentina.

  7. A geographic distribution database of the Neotropical cassava whitefly complex (Hemiptera, Aleyrodidae) and their associated parasitoids and hyperparasitoids (Hymenoptera)

    OpenAIRE

    Vásquez-Ordóñez, Aymer Andrés; Hazzi, Nicolas А.; Escobar-Prieto, David; Paz-Jojoa, Dario; Parsa, Soroush

    2015-01-01

    Abstract Whiteflies ( Hemiptera , Aleyrodidae ) are represented by more than 1,500 herbivorous species around the world. Some of them are notorious pests of cassava ( Manihot esculenta ), a primary food crop in the tropics. Particularly destructive is a complex of Neotropical cassava whiteflies whose distribution remains restricted to their native range. Despite their importance, neither their distribution, nor that of their associated parasitoids, is well documented. This paper therefore rep...

  8. Sublethal effects of some synthetic and botanical insecticides on Bemisia tabaci (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Esmaeily Saeideh

    2014-07-01

    Full Text Available In addition to direct mortality caused by insecticides, some biological traits of insects may also be affected by sublethal insecticide doses. In this study, we used the age-stage, two-sex life table method to evaluate the sublethal effects of the four synthetic insecticides: abamectin, imidacloprid, diazinon, and pymetrozin as well as the botanical insecticide taken from Calotropis procera (Asclepiadaceae extract, on eggs of the cotton whitefly, Bemisia tabaci (Hem.: Aleyrodidae. The lowest and highest survival rates and oviposition periods were observed in whiteflies treated by diazinon and imidacloprid, respectively. We found significant differences in the net reproductive rate (R0, the intrinsic rate of increase (r, the finite rate of increase (?, and the gross reproductive rate (GRR among different insecticides. Altogether, our results showed that pymetrozin and C. procera induced the most sublethal effects, thus they may be suitable candidates for use in integrated pest management programs of B. tabaci.

  9. Identifikasi kutukebul (Hemiptera: Aleyrodidae dari beberapa tanaman inang dan perkembangan populasinya

    Directory of Open Access Journals (Sweden)

    Purnama Hidayat

    2017-02-01

    Full Text Available Whiteflies (Hemiptera: Aleyrodidae can cause direct and indirect damages on plants, especially vegetables. There is only limited information regarding taxonomy and population dynamic of whiteflies attacking vegetables in Indonesia. This research is conducted to identify species of whitefly collected from chili pepper, tomato, and soybean, and to study their population dynamic. The information gathered from these studies will be useful to support whitefly management in the field. Based on morphology identification of the puparium collected directly from the host plants, there were four species of whitefly identified from chili pepper, tomato, and soybean in Bogor, Cianjur, and Sukabumi, i.e. Bemisia tabaci, Aleurodicus dispersus, Trialeurodes vaporariorum, and Dialeurodes sp. The presence of B. tabaci on chili pepper and tomato was associated with virus infection that causes yellowing and leaf curl disease. This population of B. tabaci tended to increase along with plant growth and generally reached the highest population when the plant was 60-70 days after planting.

  10. Complete Mitochondrial Genome of the Citrus Spiny Whitefly Aleurocanthus spiniferus (Quaintance (Hemiptera: Aleyrodidae: Implications for the Phylogeny of Whiteflies.

    Directory of Open Access Journals (Sweden)

    Zhi-Teng Chen

    Full Text Available In this study, we sequenced the complete mitochondrial genome (15,220 bp of the citrus spiny whitefly, Aleurocanthus spiniferus (Quaintance, a well-known pest from the superfamily Aleyrodidae. The A. spiniferus mitogenome contains 36 genes, including 13 protein-coding genes (PCGs, 21 transfer RNAs (tRNA, two ribosomal RNAs (rRNA and a large non-coding region (control region, CR. Like most whiteflies, the A. spiniferus mitogenome had a large degree of rearrangement due to translocation of the nad3-trnG-cox3 gene cluster. The 13 PCGs initiated with ATN and generally terminated with TAA, although some used TAG or T as stop codons; atp6 showed the highest evolutionary rate, whereas cox2 appeared to have the lowest rate. The A. spiniferus mitogenome had 21 tRNAs with a typical cloverleaf secondary structure composed of four arms. Modeling of the two rRNA genes indicated that their secondary structure was similar to that of other insects. The CR of A. spiniferus was 920 bp and mapped between the nad3-trnG-cox3 and trnI-trnM gene clusters. One potential stem-loop structure and five tandem repeats were identified in the CR. Phylogenetic relationships of 11 species from the Aleyrodidae were analyzed based on the deduced amino acid sequences of the 13 PCGs and evolutionary characteristics were explored. Species with more genetic rearrangements were generally more evolved within the Aleyrodidae.

  11. Homoptera, Cicadidae

    African Journals Online (AJOL)

    1988-10-24

    Oct 24, 1988 ... By comparison, P. capensis has a relatively straight, cylindrical abdomen which curves only slightly, and which does not have a distinct waist. Biology. Calling songs. The calling songs of the two taxa are illustrated in Figure. 4. The calling song of Platypleura stridula is a continuous, piercing, pulsatile noise ...

  12. Homoptera: Aphididae

    African Journals Online (AJOL)

    Once a minor pest, the pea aphid, Acyrthosiphon pisum has already become a major pest of grass pea (Lathyrus sativus), in Ethiopia, particularly in the northwestern region. The effect of two levels of chemical treatment on pea aphids and their natural enemies was investigated in a field experiment in Achefer, northwestern.

  13. Taxonomic notes on some Polyglyptini: descriptions of new genus and new species (Homoptera, Membracidae, Smiliinae

    Directory of Open Access Journals (Sweden)

    Albino M. Sakakibara

    1996-01-01

    Full Text Available Taxonomic notes on some Polyglyptini; descriptions of new genus and new species (Homoptera, Membracidae, Smiliinae. The genera Hemiptycha Germar, Metheisa Fowler, Maturnaria Metcalf, Aphetea Fowler, Dioclophara Kirkaldy, and Phormophora Stål, are redescribed; Creonus, gen.n. (type species: Maturna lloydi Funkhouser, 1914, and Aphetea robustula, sp.n. (from Bolivia, are described. Some nomenclatural changes are introduced, as follow: - Hemiptycha Germar, 1833 = Polyrhyssa Stål, 1869, syn.n.: - Hemiptycha cultrata (Coquebert, 1801, comb.n., = Polyglyptodes flavocostatus Haviland, 1925, syn.n., = Polyrhyssa cultrata maculata Fonseca, 1942, syn.n. - Hemiptycha obtecta (Fabricius, 1803 = Hille herbicola Haviland, 1925, syn.n. - Maturnaria ephippigera (Fairmaire, 1846 = Publilia tumulata Buckton, 1903, syn.n., = Metheisa fowleri Funkhouser, 1927, syn.n. - Creonus lloydi (Funkhouser, 1914, comb.n. - Aphetea parvula (Fabricius, 1803, comb.n., = Aphetea affinis Haviland, 1925, syn.n. - Dioclophara Kirkaldy, 1904 = lncolea Goding, 1926, syn.n. - Dioclophara viridula (Fairmaire, 1846 = Maturna multilineata Fonseca, 1942, syn.n. - Dioclophara variegata (Goding, 1926, comb.n. = lncolea viridis Goding, 1926, syn.n. - Phormophora maura (Fabricius, 1803 = Darnis dorsata Fabricius, 1803, syn.n.

  14. Establishment of papaya banker plant system for Parasitoid, Encarsia sophia (Hymenoptera: Aphilidae) against Bemisia tabaci (Hemiptera: Aleyrodidae) in greenhouse tomato production

    Science.gov (United States)

    The silverleaf whitefly, Bemisia tabaci biotype B (Gennadius) (Hemiptera:Aleyrodidae), is a key pest of tomato (Solanum lycopersicum L.) and other vegetable crops worldwide. To combat this pest, a non-crop banker plant system was evaluated that employs a parasitoid, Encarsia sophia (Girault & Dodd) ...

  15. Preliminary evaluation of Delphastus catalinae (Coleoptera:Coccinellidae)as a predator of the ficus whitefly, Singhiella simplex (Singh) (Hemiptera:Aleyrodidae)

    Science.gov (United States)

    The predatory lady beetle Delphastus catalinae (Horn) (Coleoptera: Coccinellidae) was evaluated as a potential biological control agent against the ficus whitefly, Singhiella simplex (Singh) (Hemiptera: Aleyrodidae), a newly-invasive pest of ficus plants. Adult D. catalinae females were starved for ...

  16. Effets biocides des alcaloïdes, des saponines et des flavonoïdes extraits de Capsicum frutescens L. (Solanaceae) sur Bemisia tabaci (Gennadius) (Homoptera : Aleyrodidae)

    National Research Council Canada - National Science Library

    Aziz Bouchelta; Abelali Blenzar; Ahmed Boughdad

    2005-01-01

    ... et des flavonoïdes extraits des fruits de Capsicum frutescens L. sur la survie des œufs et des adultes de Bemisia tabaci infestant les plants de tomates, Lycopersicon esculentum Mill. var. Daniella, a été...

  17. Facultative symbiont Hamiltonella confers benefits to Bemisia tabaci (Hemiptera: Aleyrodidae), an invasive agricultural pest worldwide.

    Science.gov (United States)

    Su, Qi; Oliver, Kerry M; Pan, Huipeng; Jiao, Xiaoguo; Liu, Baiming; Xie, Wen; Wang, Shaoli; Wu, Qingjun; Xu, Baoyun; White, Jennifer A; Zhou, Xuguo; Zhang, Youjun

    2013-12-01

    Bacterial symbionts infect most insect species, including important pests such as whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), and often exert important effects on host ecology. The facultative symbiont Hamiltonella is found at high frequencies in the B. tabaci MED (type: Mediterranean-MED) in China. The prevalence of this symbiont in natural populations suggests beneficial effects of infection or manipulation of host reproduction. To date, however, no empirical studies on the biological role of Hamiltonella on the host B. tabaci have been reported. Here, we investigated the effects of Hamiltonella infection on the sex ratio and several fitness parameters in B. tabaci MED by comparing Hamiltonella-infected whiteflies with Hamiltonella-free ones. We found that Hamiltonella-infected whiteflies produced significantly more eggs, exhibited significantly higher nymphal survival, faster development times, and larger adult body size in comparison with Hamiltonella-free whiteflies, while no evidence of reproductive manipulation by Hamiltonella were found in B. tabaci MED. In conclusion, Hamiltonella infection substantially enhanced B. tabaci MED performance. This beneficial role may, at least partially, explain the high prevalence of Hamiltonella in B. tabaci MED populations and may also contribute to their effectiveness in spread of the plant pathogens tomato yellow leaf curl virus.

  18. Cryptic Species Identification and Composition of Bemisia tabaci (Hemiptera: Aleyrodidae) Complex in Henan Province, China.

    Science.gov (United States)

    Jiu, Min; Hu, Jian; Wang, Lun-Ji; Dong, Jun-Feng; Song, Yue-Qin; Sun, Hui-Zhong

    2017-05-01

    Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a cryptic species complex, causing significant crop losses in China during the last decade. Although knowledge of cryptic species composition and dynamics within B. tabaci complex is critical for developing sustainable pest management strategies, limited information is available on this pest in the Henan province of China. A systematic survey of the cryptic species composition and distribution of B. tabaci complex in different locations of Henan province was conducted in 2012. The results of RAPD-PCR and the gene for the mitochondrial cytochrome oxidase subunit-1 (mtCOI) based phylogenetic relationships established using Bayesian method indicated there were four known cryptic species MEAM1, MED, Asia II 3, Asia II 9 and a new cryptic species named China 6 in Henan province. In the survey, the invasive cryptic species MED and MEAM1 were found to be predominant with wide spread distribution across the surveyed regions. On the contrary, the indigenous B. tabaci cryptic species including Asia II 3, Asia II 9 and China 6 remained with low prevalence in some surveyed regions. Cryptic species MEAM1 and MED have not completely displaced the native B. tabaci in Henan province. This current study for the first time unifies our knowledge of the diversity and distribution of B. tabaci across Henan province of China. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  19. Performance of Bemisia tabaci (Genn.) Biotype B (Hemiptera: Aleyrodidae) on Weeds.

    Science.gov (United States)

    Sottoriva, L D M; Lourenção, A L; Colombo, C A

    2014-12-01

    Bemisia tabaci (Genn.) biotype B (Hemiptera: Aleyrodidae) is regarded as a pest with a large number of hosts, including crops and weeds. The performance of this whitefly on seven weeds was evaluated in order to identify the most suitable host. The following weeds that are very common in intense agricultural areas in the state of São Paulo, Brazil, were selected for this study: spurge (Euphorbia heterophylla), beggarticks (Bidens pilosa), red tasselflower (Emilia sonchifolia), small-flower galinsoga (Galinsoga parviflora), pigweed (Amaranthus viridis), black nightshade (Solanum americanum), and morning glory (Ipomoea sp.). In free-choice tests, adult preference and oviposition were greatest on spurge. In contrast, morning glory was the least attractive and least oviposited plant. In assays carried out for egg-adult development, egg viability was greater than 87% over all weeds, whereas nymph viability ranged from 74 to 97%. The developmental period from egg to adult ranged from 26.7 to 49.1 days among the hosts under study. The lowest nymph density rate was observed for beggarticks and morning glory. Cluster analysis resulted in a single group formed by spurge, indicating its superiority as a host for B. tabaci biotype B. Even though the parameters evaluated indicate that spurge is the most suitable host among the weeds, all the others allow the reproduction of B. tabaci biotype B. For this reason, they should be observed during cropping and the intercrop period in areas infested by this whitefly.

  20. CASOS SELECTOS DE RESISTENCIA A INSECTICIDAS EN MOSCAS BLANCAS (Hemiptera: Aleyrodidae EN EL MUNDO

    Directory of Open Access Journals (Sweden)

    Macías-flores A

    2013-01-01

    Full Text Available Las moscas blancas (Hemíptera: Aleyrodidae son un problema a escala global. En México, llamó la atención como plaga agrícola en la década de los años 80´s y 90´s del siglo pasado por las pérdidas económicas que ocasionaron en los cultivos agrícolas, debido a los daños directos por la succión de savia y a los daños indirectos por la transmisión de enfermedades de origen viral. El hombre en su intento fallido por erradicarlas ha hecho uso desmedido de insecticidas químicos, quizás por su accesibilidad por costo bajo o por efectos de control inmediatos, por lo cual ha causado daño al medio ambiente y a la salud humana, con la consecuencia de desarrollo de resistencia. En un intento por disminuir los efectos de tales sustancias, muchas investigaciones alrededor del mundo se han conducido para encontrar productos insecticidas más efectivos con el menor impacto ambiental y a la salud humana, y que contribuyan a incrementar las herramientas de control disponibles en los sistemas de producción agrícola.

  1. Characterization of Paecilomycescinnamomeus from the camellia whitefly, Aleurocanthus camelliae (Hemiptera: Aleyrodidae), infesting tea in Japan.

    Science.gov (United States)

    Saito, Tsutomu; Takatsuka, Jun; Shimazu, Mitsuaki

    2012-05-01

    The whitefly, Aleurocanthus camelliae Kanmiya and Kasai (Hemiptera: Aleyrodidae), is an invasive species in Japan that was first discovered in 2004 on tea in Kyoto. Soon after its arrival epizootics of an entomopathogenic fungus were observed in populations of the whitefly in many tea-growing regions. Here we identify this fungus as Paecilomyces cinnamomeus (Petch) Samson and W. Gams (Hypocreales: Clavicipitaceae) based on morphological characteristics and molecular analyses. This is the first record of P. cinnamomeus in Japan and also the first time it has been recorded from the genus Aleurocanthus. A isolate of P. cinnamomeus caused greater than 50% and 90% infection in whitefly nymphs at 1×10(6) and 1×10(7)conidia/ml respectively, while the commercial mycoinsecticides Preferd® (Isaria fumosorosea) and Mycotal® (Lecanicillium muscarium) caused thiophanate-methyl caused some inhibition of in vitro growth of P. cinnamomeus isolates, and the bactericide copper oxychloride and the insecticides tolfenpyrad and methidathion were strongly inhibitory. The findings obtained in this study will be useful in the development of microbial control programs using P. cinnamomeus against A. camelliae. Copyright © 2012 Elsevier Inc. All rights reserved.

  2. Sublethal effects of some botanical and chemical insecticides on the cotton whitefly, Bemisia tabaci (Hem: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Fatemeh Jafarbeigi

    2014-09-01

    Full Text Available In addition to direct mortalities caused by acute concentrations of insecticides, some biological traits of target pests may be also affected by sublethal doses. The cotton whitefly, Bemisia tabaci (Hem: Aleyrodidae is an important pest of a wide variety of agricultural crops across the world. The control of B. tabaci largely relies on wide application of chemical insecticides. In this study, we analyzed the life table parameters to evaluate the sublethal effect of three plant-derived insecticides (Fumaria parviflora (Fumariaceae, Teucrium polium (Lamiaceae, and Thymus vulgaris (Lamiaceae and two chemical insecticides (pymetrozin and neemarin on B. tabaci. The whiteflies were allowed to oviposit on plants infected with each of the five insecticides using leaf-dip method. The data were analyzed using the age-stage two-sex life table. We found significant differences in the gross reproductive rate (GRR, the net reproductive rat (R0, the intrinsic rate of increase (r and the finite rate of increase (λ of treated whiteflies compared to control. Our results showed that some biological traits of B. tabaci are affected by sub-lethal doses of the plant-derived extracts and that these effects are comparable to those of chemical insecticides. Given the detrimental effects of chemical insecticides on human, environment and non-target organisms, plant-derived insecticides may provide valuable environmentally friendly tools for pest management programs.

  3. Effects of Powdery Mildew Fungicide Programs on Twospotted Spider Mite (Acari: Tetranychidae), Hop Aphid (Homoptera: Aphididae), and Their Natural Enemies in Hop Yards

    Science.gov (United States)

    Twospotted spider mite, Tetranychus urticae Koch (Acari:Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Homoptera:Aphidiae), are the most important arthropod pests of hop (Humulus lupulus L.) in the Northern Hemisphere. A potential barrier for greater adoption of conservation biological c...

  4. Host suitability and preference of Laricobius nigrinus (Fender) (Coleoptera: Derodontidae): a predatory beetle for potential biological control of Adelges tsugae (Annand) (Homoptera: Adelgidae)

    Science.gov (United States)

    Gabriella Zilahi-Balogh; Scott M. Salom; L. T. Kok

    2000-01-01

    Laricobius nigrinus (Coleoptera: Derodontidae) is being evaluated as a potential biological control agent of hemlock woolly adelgid (HWA), Adelges tsugae (Homoptera: Adelgidae) Annand in eastern North America. HWA is not considered a pest on western species of hemlock (McClure et al. 1996). A combination of natural enemies and host...

  5. Understanding biological control of greenhouse whitefly with the parasitoid Encarsia formosa : from individual behaviour to population dynamics

    NARCIS (Netherlands)

    Roermund, van H.J.W.

    1995-01-01

    The greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Homoptera, Aleyrodidae), is a very common, highly polyphagous pest insect all over the world. Biological control of whiteflies with the parasitoid Encarsia formosa Gahan (Hymenoptera, Aphelinidae) was already applied in the 1920s in

  6. Intraguild predation by the generalist predator Orius majusculus on the parasitoid Encarsia formosa

    DEFF Research Database (Denmark)

    Sohrabi, Fariba; Enkegaard, Annie; Shishehbor, Parviz

    2013-01-01

    Intraguild predation of Orius majusculus (Reuter) (Heteroptera: Anthocoridae) on Encarsia formosa (Gahan) (Hymenoptera: Aphelinidae), both natural enemies of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae), was studied under laboratory conditions. The experiments quantified prey consumption b...

  7. Amitus fuscipennis, an alternative to the biological control of Trialeurodes vaporariorum by Encarsia formosa?

    NARCIS (Netherlands)

    Vis, de R.M.J.; Lenteren, van J.C.

    2008-01-01

    Biological control of Trialeurodes vaporariorum (Homoptera Aleyrodidae) by Amitus fuscipennis (Hymenoptera Platygastridae) with or without Encarsia formosa (Hymenoptera Aphelinidae) was tested in both a glasshouse and a plastic greenhouse during two consecutive production cycles of a beef tomato

  8. No-choice ovipositional nonpreference of Bemisia tabaci (Gennadius B biotype on tomato genotypes Não-preferência para oviposição de Bemisia tabaci (Gennadius biótipo B em genótipos de tomateiro em teste sem chance de escolha

    Directory of Open Access Journals (Sweden)

    Maria Auxiliadora de Godoy Oriani

    2011-04-01

    Full Text Available Brazil is one of the main tomato producers worldwide. Nevertheless, 40 to 70% of the production is lost due to Bemisia tabaci (Gennadius B biotype attacks. Resistant plant germplasm can be an important method for controlling this pest in an integrated pest management program. This research aimed to evaluate the no-choice ovipositional preference of B. tabaci B biotype on 18 tomato genotypes with different densities and types of trichomes testing two screening techniques and to determine the influence of trichomes on whitefly ovipositional preference. Two methods of confinement experiments were used. Leaflets detached from the upper third part of the tomato plants (first experiment and 30-day-old plants (second experiment were infested with whiteflies during 24 h. For the first experiment, simple linear correlation tests between the number of insects and eggs, and number of trichomes in the tomato genotypes were carried out. The first technique was better than the second one, as it was easier to carry out and the evaluation demanded less time and as well as was effective to discriminate the resistance level of the evaluated genotypes. Glandular trichomes had a negative correlation with attracted adults and number of eggs deposited, and a positive correlation with number of trapped insects. Negative correlations were observed between number of nonglandular trichomes and trapped insects, and also between total number of trichomes and attracted and trapped insects. Positive correlations were observed between number of total trichomes and eggs cm-2 and nonglandular trichomes and number of eggs. Both confinement methods efficiently discriminated whitefly oviposition among genotypes, especially the resistant ones. High levels of antixenosis for oviposition related to type IV glandular trichomes were exhibited by genotypes LA716, PI134417 and PI134418. The high level of ovipositional preference by B. tabaci for genotypes LA1963 and NAV1062 was related

  9. Characterization of a Newly Discovered Symbiont of the Whitefly Bemisia tabaci (Hemiptera: Aleyrodidae)

    Science.gov (United States)

    Bing, Xiao-Li; Yang, Jiao; Zchori-Fein, Einat; Wang, Xiao-Wei

    2013-01-01

    Bemisia tabaci (Hemiptera: Aleyrodidae) is a species complex containing >28 cryptic species, some of which are important crop pests worldwide. Like many other sap-sucking insects, whiteflies harbor an obligatory symbiont, “Candidatus Portiera aleyrodidarum,” and a number of secondary symbionts. So far, six genera of secondary symbionts have been identified in B. tabaci. In this study, we report and describe the finding of an additional bacterium in the indigenous B. tabaci cryptic species China 1 (formerly known as B. tabaci biotype ZHJ3). Phylogenetic analysis based on the 16S rRNA and gltA genes showed that the bacterium belongs to the Alphaproteobacteria subdivision of the Proteobacteria and has a close relationship with human pathogens of the genus Orientia. Consequently, we temporarily named it Orientia-like organism (OLO). OLO was found in six of eight wild populations of B. tabaci China 1, with the infection rate ranging from 46.2% to 76.8%. Fluorescence in situ hybridization (FISH) of B. tabaci China 1 in nymphs and adults revealed that OLOs are confined to the bacteriome and co-occur with “Ca. Portiera aleyrodidarum.” The vertical transmission of OLO was demonstrated by detection of OLO at the anterior pole end of the oocytes through FISH. Quantitative PCR analysis of population dynamics suggested a complex interaction between “Ca. Portiera aleyrodidarum” and OLO. Based on these results, we propose “Candidatus Hemipteriphilus asiaticus” for the classification of this symbiont from B. tabaci. PMID:23144129

  10. Ecology and management of the woolly whitefly (Hemiptera: Aleyrodidae), a new invasive citrus pest in Ethiopia.

    Science.gov (United States)

    Belay, Difabachew K; Zewdu, Abebe; Foster, John E

    2011-08-01

    Distribution and importance of woolly whitefly (Aleurothrixus floccosus) (Maskell) (Hemiptera: Aleyrodidae), was studied in Ethiopia with an evaluation of treatments against it. Results showed that the pest is distributed in most citrus-growing parts of the country equally infesting all types of citrus crops. Only one pupal parasitoid, Amitus sp., was recorded at Melkaoba. During 2006-2007, eight treatments gave better control of woolly whitefly compared with the control: endod (Phytolacca dodecandra L'Herit) berry extract, white oil 80%, neem oil, omo detergent soap, band application of gasoline, cyhalothrin (karate) 5% EC, selecron (profenofos) 500 EC, and rimon (novaluron) 10 EC. Treatments were applied on 6-8 yr-old orange trees at Melkaoba and Nazareth. At Melkaoba, application of cyhalothrin, selecron, white oil, and Neem gave better control of woolly whitefly compared with the control. All the treatments resulted in a lower number of ants than the control. Ants disrupt biocontrol agents of honeydew-secreting pests, including woolly whiteflies. Mean infestation score was higher in the control than the rest of the treatments. Similarly, at Nazareth, woolly whitefly numbers were lower recorded on cyhalothrin-treated plants. However, the numbers of eggs were significantly higher in endod extract-sprayed plants than the control. All treatments controlled ants better than the control except endod. Infestation scores were lower on endod- and cyhalothrin-treated plants than the control. Mean number of adult woolly whiteflies and eggs were significantly higher on newly grown leaves than older leaves. In general, the number of live adult woolly whiteflies showed a decreasing trend at both sites after treatment applications compared with the control.

  11. Control of whiteflies and aphids in tomato ( Solanum lycopersicum L ...

    African Journals Online (AJOL)

    Whitefly (Bemisia tabaci, Homoptera: Aleyrodidae) and aphid (Homoptera) on tomato (Solanum lycopersicum L.) are economically important insect pests that are difficult to manage due to their resistance to a wide range of chemical pesticides. Field experiments were conducted to assess the effects of fermented plant ...

  12. First record of occurrence of mosca-negra-dos-citrus, Aleurocanthus woglumi Ashby, 1915 (Hemiptera: Sternorrhyncha: Aleyrodidae in Roraima, Brazil = Primeiro registro da ocorrência de mosca-negra-dos-citros, Aleurocanthus woglumi Ashby, 1915 (Hemiptera: Aleyrodidae em Roraima

    Directory of Open Access Journals (Sweden)

    Francisco Clemilto da Silva Maciel

    2011-12-01

    Full Text Available The Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae is an important pest of citrus. Originated in Asia, this pest was detected in Brazil for the first time in the State of Para, Brazil in 2001. In the culture of citrus fruits the black fly carries direct and indirect damage, impeding the development and production of plants. In addition to restricting trade in local areas from its occurrence to the presence of the plague, since the A. woglumi quarantine pest is considered present (A2 of high alert in accordance with Instruction No 23, April 29, 2008, established by the Ministério da Agricultura, Pecuária e Abastecimento of the Brazil. The objective of this paper was to record the first occurrence of Aleurocanthus woglumi in the State of Roraima, Brazil.= A mosca-negra-dos-citros, Aleurocanthus woglumi Ashb, (Hemiptera: Aleyrodidae é uma importante praga dos citros. De origem asiática, esta praga foi detectada no Brasil pela primeira vez no estado do Pará no ano de 2001. Na cultura dos citros a mosca-negra acarreta danos diretos e indiretos, prejudicando o desenvolvimento e produção das plantas. Além de restringir o comércio de locais de sua ocorrência para áreas livres da presença da praga, visto que o A. woglumi é considerado praga quarentenária presente (A2 de alerta máximo de acordo com a instrução normativa No 23, de 29 de abril de 2008; estabelecida pelo Ministério da Agricultura, Pecuária e Abastecimento. Objetivou-se com o presente trabalho registrar a primeira ocorrência de mosca-negra-dos-citros no estado de Roraima.

  13. Effects of operational and environmental factors on evolution of resistance to pyriproxyfen in the sweetpotato whitefly (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Crowder, David W; Ellsworth, Peter C; Tabashnik, Bruce E; Carriére, Yves

    2008-12-01

    Pyriproxyfen has been an important insecticide used as part of an integrated pest management (IPM) program for the sweetpotato whitefly, Bemisia tabaci (Gennadius) (B biotype), in Arizona cotton. We used a simulation model to examine the effects of pyriproxyfen concentration, insecticide action thresholds, crop diversity, planting date, and pyriproxyfen decay on evolution of resistance to pyriproxyfen in B. tabaci. In the model, pyriproxyfen use was restricted to cotton with a limit of one application per season. Other model parameters were based on data from laboratory and field experiments. Whitefly population densities and the number of insecticide applications per year increased as resistance evolved. Resistance evolved slowest with a low pyriproxyfen concentration. Lower action thresholds for pyriproxyfen and higher action thresholds for insecticides other than pyriproxyfen also slowed the evolution of resistance. However, lower action thresholds for pyriproxyfen resulted in more insecticide sprays per year with a high pyriproxyfen concentration. Resistance to pyriproxyfen evolved fastest in cotton-intensive regions and slowest in multicrop regions. In regions with noncotton crops, increasing immigration to cotton slowed resistance. Resistance evolved faster with earlier planting dates, although fewer insecticide sprays were needed compared with fields planted later in the year. Faster rates of pyriproxyfen decay slowed resistance. In some cases, strategies that delayed resistance were effective from an IPM perspective. However, some strategies that delayed resistance resulted in higher population densities. Results suggest that modification of operational and environmental factors, which can be controlled by growers, could prolong the efficacy of pyriproxyfen.

  14. Evaluating sex pheromone monitoring as a tool in the integrated management of vine mealybug, Planococcus ficus (signoret) (Homoptera: Pseudococcidae) / M.J. Kotze

    OpenAIRE

    Kotze, Maria Johanna

    2006-01-01

    The vine mealybug, Planococcus ficus (Signoret) (Homoptera: Pseudococcidae) is a pest with significant economic impact on the grape growing industry in South Africa and other parts of the world. With the isolation and synthesizing of the vine mealybug sex pheromone in 2001, new control options for the integrated management of the vine mealybug have been created. The status of sex pheromone monitoring as a tool in the integrated management of the vine mealybug has been evaluated from...

  15. Genetic diversity of Costa Rican populations of the rice planthopper Tagosodes orizicolus (Homoptera: Delphacidae

    Directory of Open Access Journals (Sweden)

    Myriam Hernández

    2004-09-01

    Full Text Available Tagosodes orizicolus (Homoptera: Delphacidae is one of the main constraints of the rice production in the Neotropics. This planthopper produces severe damages as a phloem feeder, causes mechanical injury during oviposition and vectors the rice hoja blanca virus (RHBV. The main objective of this study was to determine the genetic diversity of T. orizicolus populations from three rice growing regions of Costa Rica, using RAPDs. Individuals from Guanacaste, Parrita, San Carlos and Cali-Colombia, as outgroup, were analyzed using the random primers. Phenetic relationships revealed that the Costa Rican populations were clearly separated from Cali-Colombia, sharing less than 25% similarity. Costa Rican populations were divided into two main branches separated at 30% similarity. The first branch included Guanacaste and San Carlos and the second displayed Parrita. In relation to similarity indexes within groups, the Guanacaste cluster showed the highest (over 50% and Cali-Colombia was the most diverse (28%. The correspondence analysis confirmed the clusters of the phenogram and showed close interactions between the Parrita and San Carlos populations. The genetic separation observed could be the result of the geographic isolation among populations, but it could also be explained by the infection with the rickettsia Wolbachia pipientis. This bacterium causes cytoplasmic incompatibility in its host, which results in non-viable progeny when infected males mate with non-infected females, or when insects hosting different strains of Wolbachia mate. Then, a search for Wolbachia in previously described populations of T. orizicolus was initiated. The presence of the bacteria was analyzed by PCR with 16S rDNA-specific primers for Wolbachia. The PCR analyses revealed infections of 86% in the population of San Carlos, 96% in Guanacaste, 37% in Parrita and 100% in Cali-Colombia. Crosses between individuals of T. orizicolus from Parrita and Guanacaste were performed

  16. The Cuticle Protein Gene MPCP4 of Myzus persicae (Homoptera: Aphididae) Plays a Critical Role in Cucumber Mosaic Virus Acquisition.

    Science.gov (United States)

    Liang, Yan; Gao, Xi-Wu

    2017-06-01

    Myzus persicae (Sulzer) (Homoptera: Aphididae) is one of the most important agricultural pests worldwide. In addition to sucking phloem sap, M. persicae also transmits Cucumber mosaic virus (CMV) as a vector in a nonpersistent manner. At present, the infection mechanism remains unclear, especially the process of aphid virus acquisition. In this study, we isolated four M. persicae cuticle protein genes (MPCP1, MPCP2, MPCP4, and MPCP5) from M. persicae. The relative amount of the gene encoding Cucumber mosaic virus capsid protein (CMV CP) and the transcript levels of these four cuticle protein genes were investigated in aphid virus acquisition by feeding the tobacco preinfested by CMV. The relative expression of MPCP1, MPCP2, and MPCP4 were significantly higher than MPCP5 at 24 h after aphids feeding on virus-infested tobacco. Yeast two-hybrid assays demonstrated that the protein encoded by MPCP4 gene was closely associated with the CMV CP through the direct interaction. Moreover, the ability of M. persicae to acquire CMV was suppressed by RNA interference of MPCP4. All these lines of evidence indicate that MPCP4, as a viral putative receptor in the stylet of aphid, plays an important role in aphid acquisition of CMV. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Taxonomic Status of the Bemisia tabaci Complex (Hemiptera: Aleyrodidae) and Reassessment of the Number of Its Constituent Species

    Science.gov (United States)

    Lee, Wonhoon; Park, Jongsun; Lee, Gwan-Seok; Lee, Seunghwan; Akimoto, Shin-ichi

    2013-01-01

    Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B. tabaci complex were determined based on 1059 COI sequences of B. tabaci and 509 COI sequences of 153 hemipteran species. The genetic divergence within B. tabaci was conspicuously higher (on average, 11.1%) than interspecific genetic divergence within the respective genera of the 153 species (on average, 6.5%). This result indicates that B. tabaci is composed of multiple species that may belong to different genera or subfamilies. A phylogenetic tree constructed based on 212 COI sequences without duplications revealed that the B. tabaci complex is composed of a total of 31 putative species, including a new species, JpL. However, genetic divergence within six species (Asia II 1, Asia II 7, Australia, Mediterranean, New World, and Sub Saharan Africa 1) was higher than 3.5%, which has been used as a threshold of species boundaries within the B. tabaci complex. These results suggest that it is necessary to increase the threshold for species boundaries up to 4% to distinguish the constituent species in the B. tabaci complex. PMID:23675507

  18. Taxonomic status of the Bemisia tabaci complex (Hemiptera: Aleyrodidae and reassessment of the number of its constituent species.

    Directory of Open Access Journals (Sweden)

    Wonhoon Lee

    Full Text Available Bemisia tabaci (Hemiptera: Aleyrodidae is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B. tabaci complex were determined based on 1059 COI sequences of B. tabaci and 509 COI sequences of 153 hemipteran species. The genetic divergence within B. tabaci was conspicuously higher (on average, 11.1% than interspecific genetic divergence within the respective genera of the 153 species (on average, 6.5%. This result indicates that B. tabaci is composed of multiple species that may belong to different genera or subfamilies. A phylogenetic tree constructed based on 212 COI sequences without duplications revealed that the B. tabaci complex is composed of a total of 31 putative species, including a new species, JpL. However, genetic divergence within six species (Asia II 1, Asia II 7, Australia, Mediterranean, New World, and Sub Saharan Africa 1 was higher than 3.5%, which has been used as a threshold of species boundaries within the B. tabaci complex. These results suggest that it is necessary to increase the threshold for species boundaries up to 4% to distinguish the constituent species in the B. tabaci complex.

  19. Further spread of and domination by Bemisia tabaci (Hemiptera: Aleyrodidae) biotype Q on field crops in China.

    Science.gov (United States)

    Pan, Huipeng; Chu, Dong; Ge, Daqing; Wang, Shaoli; Wu, Qingjun; Xie, Wen; Jiao, Xiaoguo; Liu, Baiming; Yang, Xin; Yang, Nina; Su, Qi; Xu, Baoyun; Zhang, Youjun

    2011-06-01

    The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), causes severe crop losses to many crops. The worst of these losses are often associated with the invasion and establishment of biotypes B and Q of this pest. Previous research in 2007 showed that biotype Q occurred with other biotypes in most field populations in China. To determine the current status of the biotype composition in the field, an extensive survey covering mainly eastern parts of China was conducted in 2009. Using polymerase chain reaction primers specific for the mitochondrial cytochrome oxidase I of biotypes B and Q and gene sequencing, we determined the biotypes composition in 61 whitefly populations and their distribution across 19 provinces in China. Our research revealed that only biotypes B and Q have been found in the field in 2009 in China. Among them, biotype Q was dominant in 44 locations (100.0%) and biotype B was dominant in 17 locations (100.0%). The current survey indicates that biotype Q has rapidly displaced biotype B in most locations in China.

  20. Nitrogen in Hydroponic Growing Medium of Tomato Affects the Demographic Parameters of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Hosseini, R S; Madadi, H; Hosseini, M; Delshad, M; Dashti, F

    2015-12-01

    We evaluated the effects of different nitrogen levels (380, 310, 240, and 174 ppm) on the life history parameters of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) on hydroponically cultured tomato plants. Our data show that there is a positive correlation between the nitrogen content and the demographic parameters, as the intrinsic rate of increase of T. vaporariorum was the lowest (0.059 ± 0.007 day(-1)) at 174 ppm and the highest (0.088 ± 0.005 day(-1)) at 380 ppm of nitrogen. The net reproduction rate (R 0), finite rate of increase (λ), and mean developmental time (T) were significantly influenced by the nitrogen levels. The mean longevity of males and females showed a positive relationship with the nitrogen level, ranging from 64.8 ± 3.96 to 76.3 ± 2.44 for males and 61.6 ± 5.35 to 71.2 ± 2.44 for females, observed in the lowest and highest nitrogen levels, respectively. The relationship between nitrogen fertilization and T. vaporariorum management on tomato crops is discussed.

  1. A geographic distribution database of the Neotropical cassava whitefly complex (Hemiptera, Aleyrodidae) and their associated parasitoids and hyperparasitoids (Hymenoptera).

    Science.gov (United States)

    Vásquez-Ordóñez, Aymer Andrés; Hazzi, Nicolas A; Escobar-Prieto, David; Paz-Jojoa, Dario; Parsa, Soroush

    2015-01-01

    Whiteflies (Hemiptera, Aleyrodidae) are represented by more than 1,500 herbivorous species around the world. Some of them are notorious pests of cassava (Manihot esculenta), a primary food crop in the tropics. Particularly destructive is a complex of Neotropical cassava whiteflies whose distribution remains restricted to their native range. Despite their importance, neither their distribution, nor that of their associated parasitoids, is well documented. This paper therefore reports observational and specimen-based occurrence records of Neotropical cassava whiteflies and their associated parasitoids and hyperparasitoids. The dataset consists of 1,311 distribution records documented by the International Center for Tropical Agriculture (CIAT) between 1975 and 2012. The specimens are held at CIAT's Arthropod Reference Collection (CIATARC, Cali, Colombia). Eleven species of whiteflies, 14 species of parasitoids and one species of hyperparasitoids are reported. Approximately 66% of the whitefly records belong to Aleurotrachelus socialis and 16% to Bemisia tuberculata. The parasitoids with most records are Encarsia hispida, Amitus macgowni and Encarsia bellottii for Aleurotrachelus socialis; and Encarsia sophia for Bemisia tuberculata. The complete dataset is available in Darwin Core Archive format via the Global Biodiversity Information Facility (GBIF).

  2. Populations of predators and parasitoids of Bemisia tabaci (Hemiptera: Aleyrodidae) after the application of eight biorational insecticides in vegetable crops.

    Science.gov (United States)

    Simmons, Alvin M; Shaaban, Abd-Rabou

    2011-08-01

    The sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), is an important pest of vegetables and many other crops worldwide. Eight biorational insecticides (based on oil, plant derivatives, insect growth regulator and fungus) were evaluated in the field for their influence on populations of six natural enemies of B. tabaci. Natural populations of two predators [Chrysoperla carnea Stephen (Neuroptera: Chrysopidae) and Orius spp. (Hemiptera: Anthocoridae)] and two genera of parasitoids [Encarsia spp. and Eretmocerus spp. (Hymenoptera: Aphelinidae)] were evaluated in eggplant (Solanum melongena L.). Also, augmented field populations of three predators [C. carnea, Coccinella undecimpunctata L. (Coleoptera: Coccinellidae) and Macrolophus caliginosus (Wagner) (Hemiptera: Miridae)] were evaluated in cabbage (Brassica oleracea var. capitata L.), cucumber (Cucumis sativus L.) and squash (Cucurbita pepo L.). Regardless of natural enemy or crop, jojoba oil, Biovar and Neemix had the least effect on abundance of the natural enemies in comparison with the other insecticides during a 14 day evaluation period. Conversely, Admiral, KZ oil, Mesrona oil, Mesrona oil + sulfur and natural oil had a high detrimental effect on abundance of the natural enemies. These results demonstrate the differential effects of biorational insecticides for whitefly control on predators and parasitoids in the field. This article is a US Government work and is in the public domain in the USA. Published 2011 by John Wiley & Sons, Ltd.

  3. Aspectos biológicos de Coccidophilus citricola (Coleoptera, Coccinellidae sobre Aspidiotus nerii e Chrysomphalus aonidum (Homoptera, Diaspididae Biological studies of Coccidophilus citricola (Coleoptera, Coccinellidae on Aspidiotus nerii and Chrysomphalus aonidum (Homoptera, Diaspididae

    Directory of Open Access Journals (Sweden)

    Antonio Cesar dos Santos

    2005-02-01

    Full Text Available Aspectos biológicos de Coccidophilus citricola Brèthes (Coleoptera, Coccinellidae foram estudados sobre Chrysomphalus aonidum Linnaeus e Aspidiotus nerii Bouchè (Homoptera, Diaspididae criadas sobre abóbora. Observou-se a duraç��o (dias do período de ovo, dos quatro ínstares, pré-pupa, pupa, longevidade de adultos e a proporção machos: fêmeas de C. citricola. Determinou-se também verificar a eficiência de predação de adultos de C. citricola sobre A. nerii. C. aonidum e A. nerii são presas adequadas para C. citricola, com desenvolvimento semelhante do coccinelídeo sobre essas cochonilhas; o período de incubação do ovo foi de 7,9 e 8,1 dias com A. nerii e C. aonidum; a duração (dias de cada ínstar larval de C. citricola sobre A. nerii e C. aonidum foram respectivamente de: (I 2,7 e 2,9; (II 3,1 e 3,3; (III 3,0 e 3,3 e (IV 3,2 e 3,1 dias. A duração das fases de pré-pupa e pupa foi de 2,5 e 4,5 dias sobre A. nerii e 2,8 e 4,8 dias sobre C. aonidum e a viabilidade de ovo a adulto foi de 63,2% e 62,7% respectivamente para indivíduos criados sobre essas presas. A longevidade de adultos de C. citricola foi de 57,0 dias com A. nerii e de 62,0 dias com C. aonidum. A proporção macho: fêmea foi de 0,82:1,00. O consumo diário de C. citricola foi de 1,15 adultos ou 2,35 ninfas de 2o ínstar ou 3,16 ninfas de 1o ínstar de A. nerii por dia.Laboratory trials were carried out to study biological aspects of Coccidophilus citricola Brèthes (Coleoptera: Coccinellidae on Chrysomphalus aonidum Linnaeus and Aspidiotus nerii Bouché (Homoptera: Diaspididae. The scales were reared on squashes and then served as food source to the predator. The period of egg, larvae (four ínstars, pre-pupae, pupae, adults’ longevity and male: female ratio was observed. Predatory efficacy of C. citricola on A. nerii was also determined. The period of egg was 7.9 and 8.1 days on A. nerii and C. aonidum. The development (days of different stages of C

  4. Factors affecting herbivory of Thrips palmi (Thysanoptera: Thripidae and Aphis gossypii (Homoptera: Aphididae on the eggplant (Solanum melongena

    Directory of Open Access Journals (Sweden)

    Germano Leão Demolin Leite

    2006-05-01

    Full Text Available The objective of this study was to evaluate effects of total rainfall, mean temperature, natural enemies, chemical composition of leaves, levels of nitrogen and potassium on leaves and density of leaf trichomes on attack intensity of Thrips palmi Karny (Thysanoptera: Thripidae and Aphis gossypii (Glover (Homoptera: Aphididae on plantations of the eggplant (Solanum melongena in two regions of Minas Gerais, Brazil. Higher numbers of A. gossypii/leaf and T. palmi/leaf were observed in plantations of this eggplant in the Municipalities of Viçosa and Guidoval, respectively. Guidoval had a rainy and hotter weather than Viçosa. T. palmi was almost positivelly correlated with rainfall (r= 0.49, P= 0.0538 while A. gossypii seemed to be more affected by mean temperature (r= -0.31; P= 0.1134. Higher number of aphids in eggplants in Viçosa than in Guidoval could be explained by the higher number of natural enemies such as Adialytus spp. (Hymenoptera: Braconidae, Cycloneda sanguinea (L. and Exochomus bimaculosus Mulsant (Coleoptera: Coccinellidae and Chrysoperla spp. (Neuroptera: Chrysopidae in this municipality. However, only Adialytus spp. was significativelly correlated with aphid populations. Higher number of T. palmi in eggplant plantations of Guidoval than in Viçosa could be due to the absence of its possible Eulophidae parasitoid in the first municipality. The spiders were significativelly correlated with this pest in both municipalities.O objetivo deste estudo foi avaliar os efeitos de pluviosidade total, temperatura média, inimigos naturais, composição química foliar, níveis de nitrogênio e potássio foliar e densidade de tricomas na intensidade de ataque de Thrips palmi Karny (Thysanoptera: Thripidae e Aphis gossypii (Glover (Homoptera: Aphididae em plantações de berinjela (Solanum melongena em dois municípios de Minas Gerais, Brasil. Observou-se maiores números de A. gossypii e T. palmi por folha em plantações de berinjela nos

  5. Host plant effects on alkaline phosphatase activity in the whiteflies, Bemisia tabaci Biotype B and Trialeurodes vaporariorum.

    Science.gov (United States)

    Yan, Ying; Peng, Lu; Liu, Wan-Xue; Wan, Fang-Hao; Harris, Marvin K

    2011-01-01

    Bemisia tabaci (Gennadius) B-biotype and Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) often coexist on greenhouse-grown vegetable crops in northern China. The recent spread of B. tabaci B-biotype has largely replaced T. vaporariorum, and B-biotype now overlaps with T. vaporariorum where common hosts occur in most invaded areas. The impact of the B-biotype on the agro eco system appears to be widespread, and involves the ability to compete with and perhaps replace other phytophages like T. vaporariorum. An emerging hypothesis is that the B-biotype is physiologically superior due at least in part to an improved ability to metabolically utilize the alkaline phosphatase pathway. To test this hypothesis, alkaline phosphatase activity was studied in the B-biotype and T. vaporariorum after feeding on a number of different hosts for a range of durations, with and without host switching. Alkaline phosphatase activity in T. vaporariorum was 1.45 to 2.53-fold higher than that of the B-biotype when fed on tomato for 4 and 24 h, or switched from tomato to cotton and cabbage for the same durations. However, alkaline phosphatase activity in the B-biotype was 1.40 to 3.35-fold higher than that of T. vaporariorum when the host switching time was ∼72 and ∼120 h on the same plant. Both short-term (4 h) and long-term (72 h) switching of plant hosts can significantly affect the alkaline phosphatase activity in the two species. After ∼120 h, feeding on tomato and cotton alkaline phosphatase activity in the B-biotype was significantly higher than that of T. vaporariorum. It was shown that alkaline phosphatase aids the species feeding on different plant species, and that the B-biotype is physiologically superior to T. vaporariorum in utilizing the enzyme compared to T. vaporariorum over longer periods of feeding.

  6. Leaf endophytic fungi of chili (Capsicum annuum and their role in the protection against Aphis gossypii (Homoptera: Aphididae

    Directory of Open Access Journals (Sweden)

    HENY HERNAWATI

    2011-10-01

    Full Text Available Hernawati H, Wiyono S, Santoso S (2011 Leaf endophytic fungi of chili (Capsicum annuum and their role in the protection against Aphis gossypii (Homoptera: Aphididae. Biodiversitas 12: 187-191. The objectives of the research were to study the diversity of leaf endophytic fungi of chili, and investigate its potency in protecting host plants against Aphis gossypii Glov. Endophytic fungi were isolated from chili leaves with two categories: aphid infested plants and aphid-free plants, collected from farmer’s field in Bogor, West Java. Abundance of each fungal species from leave samples was determined by calculating frequency of isolation. The isolated fungi were tested on population growth of A. gossypii. The fungal isolates showed suppressing effect in population growth test, was further tested on biology attributes i.e. life cycle, fecundity and body length. Five species of leaf endophytic fungi of chili were found i.e. Aspergillus flavus, Nigrospora sp., Coniothyrium sp., and SH1 (sterile hypha 1, SH2 (sterile hypha 2. Eventhough the number of endophytic fungi species in aphid-free and aphid-infested plant was same, the abundance of each species was different. Nigrospora sp., sterile hyphae 1 and sterile hyphae 2 was more abundant in aphid-free plants, but there was no difference in dominance of Aspergillus flavus and Coniothyrium sp. Nigrospora sp., SH1 and SH2 treatment reduced significantly fecundity of A. gossypii. Only SH2 treatment significantly prolonged life cycle and suppress body length, therefore the fungus had the strongest suppressing effect on population growth among fungi tested. The abundance and dominance of endophytic fungal species has relation with the infestation of A. gossypii in the field.

  7. Relative suitability of crested wheatgrass and other perennial grass hosts for the Russian wheat aphid (Homoptera: Aphididae).

    Science.gov (United States)

    Donahue, J D; Brewer, M J; Burd, J D

    2000-04-01

    The Russian wheat aphid, Diuraphis noxia (Mordvilko) (Homoptera: Aphididae), reproduces parthenogenetically in North America and must survive year-round on host plants, including in late summer when small grains are not in cultivation. During this time, cool-season perennial wheatgrasses (Poaceae: Triticeae) contribute substantially to aphid survival, crested wheatgrass (Agropyron spp.) particularly. In greenhouse studies, the number of aphids per plant was measured after four infestation periods on unvernalized and vernalized wheatgrasses. Before placement on these test plant species, aphids were reared either on winter wheat or on the grass host species on which aphid progeny were counted. On vernalized plants, aphids reared on wheat resulted in more aphids per test plant than when the aphids were reared on wheatgrasses, but on unvernalized plants the number of aphids per test plant did not differ significantly regardless of rearing host. Aphids on crested wheatgrass were similar in number to the other grasses when plants were unvernalized. However, when plants were vernalized, crested wheatgrass supported significantly more aphids than some of the other hosts. Aphid numbers increased on all test species as infestation period lengthened, and plant growth was largely unaffected by aphid feeding. These results suggest if sufficient moisture is available during summer when small grains are not in cultivation, all host species observed are capable of sustaining aphids. Crested wheatgrass is an abundant and important host of the Russian wheat aphid in its northern range of the western United States, but other less prevalent wheatgrasses also may contribute to aphid survival during late summer when small grains are not in cultivation.

  8. Analysis of Species, Subgroups, and Endosymbionts of Bemisia tabaci (Hemiptera: Aleyrodidae) From Southwestern Cotton Fields in Turkey.

    Science.gov (United States)

    Karut, Kamil; Mete Karaca, M; Döker, Ismail; Kazak, Cengiz

    2017-08-01

    Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is one of the most important insect pests worldwide including Turkey. Although there are substantial data regarding species composition of Turkish B. tabaci populations, the situation is still not clear and further investigations are needed. Therefore, in this study, species and subgroups of B. tabaci collected from cotton fields in southwestern part of Turkey (Antalya, Aydın, Denizli, and Muğla) were determined using microsatellite analysis, AluI-based mtCOI polymerase chain reaction-random length polymorphism, and sequencing. Secondary endosymbionts were also determined using diagnostic species-specific PCR. Middle East Asia Minor 1 (MEAM1), Mediterranean (MED) Q1, and MED Q2 were the species and subgroups found in this study. The MED species (85.3%) were found to be more dominant than MEAM1. Species status of B. tabaci varied depending on the location. Although all samples collected from Aydın were found to be Q1, three species and subgroups were found in Muğla. Secondary endosymbionts varied according to species and subgroups. Arsenophonus was found only from Q2, while Hamiltonella was detected in MEAM1 and Q1. In addition, high Rickettsia and low Wolbachia infections were detected in MEAM1 and Q1 populations, respectively. In conclusion, for the first time, we report the presence and symbiotic communities of Q1 from Turkey. We also found that the symbiont complement of the Q1 is more congruent with Q1 from Greece than other regions of the world, which may have some interesting implications for movement of this invasive subgroup. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Thermotolerance and Heat-Shock Protein Gene Expression Patterns in Bemisia tabaci (Hemiptera: Aleyrodidae) Mediterranean in Relation to Developmental Stage.

    Science.gov (United States)

    Jiang, Rui; Qi, Lan-Da; Du, Yu-Zhou; Li, Yuan-Xi

    2017-10-01

    Temperature plays an important role in the growth, development, and geographic distribution of insects. There is convincing evidence that heat-shock proteins (HSPs) play important roles in helping organisms adapt to thermal stress. To better understand the physiological and ecological influence of thermal stress on the different development stages of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) Mediterranean species (MED), nymphs and adults were shocked with temperatures of 35, 38, and 41℃ for 1 and 2 h, respectively, and the survival rate, fecundity, and developmental duration were investigated in the laboratory. The expression levels of the hsp40, hsp70, and hsp90 genes were assessed using real-time PCR. The results indicate that the survival rates of the nymphs and adults decreased with increased temperature. A 2-h heat shock at 41℃ induced a significant reduction in fecundity in adults and an increase in developmental duration in young nymphs. Hsp90 showed higher temperature responses to thermal stress than hsp40 or hsp70. The expression levels of the hsps in the adults were significantly down-regulated by a 2-h heat shock at 41℃ compared with that by a 1-h treatment. A significant decrease in the expression levels of the hsps also occurred in the adults when the temperature increased from 38 to 41℃ for the 2-h treatment, whereas no significant decrease occurred in the nymphs. Compared with previous studies, we provide some evidence indicating that MED has the potential to adapt to a wider temperature range than the Middle East-Asia Minor 1 species. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Multiple generation effects of high temperature on the development and fecundity of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) biotype B.

    Science.gov (United States)

    Guo, Jian-Ying; Cong, Lin; Wan, Fang-Hao

    2013-08-01

    Insects are ectotherms and their ability to resist temperature stress is limited. The immediate effects of sub-lethal heat stress on insects are well documented, but longer-term effects of such stresses are rarely reported. In this study, survival, development and reproduction of the whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) biotype B, were compared over five consecutive generations at 27, 31 and 35 °C and for one generation at 37 °C. Both temperature and generation significantly affected the fitness of the whitefly. These impacts were more dramatic with increasing generations and temperatures. Among the experimental temperatures, the most favorable for development and reproduction were 27 °C and 31 °C. At 27 °C, survival, development and fecundity were all stable over these five generations. At 31 °C, immature survival rate was the highest in the fifth generation, but female fecundities decreased in the fourth and fifth generations. At 35 °C, egg hatching rate, immature survival rate and female fecundity decreased significantly in the fourth and fifth generations. At 37 °C, survival of B. tabaci was not adversely affected, but female fecundity at 37 °C was less than 10% of that at 27 °C or 31 °C. These results demonstrate that the lethal high temperature for B. tabaci is over 37 °C, and the whitefly population continued expanding in the five generations at 35 °C. The ability of B. tabaci biotype B to survive high temperature stress will play an important role in its population extension under global warming. © 2012 The Authors Insect Science © 2012 Institute of Zoology, Chinese Academy of Sciences.

  11. Lethal and Inhibitory Activities of Plant-Derived Essential Oils Against Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) Biotype B in Tomato.

    Science.gov (United States)

    Fanela, T L M; Baldin, E L L; Pannuti, L E R; Cruz, P L; Crotti, A E M; Takeara, R; Kato, M J

    2016-04-01

    The silverleaf whitefly Bemisia tabaci (Genn.) biotype B (Hemiptera: Aleyrodidae) is one of the most severe tomato pests in the world. The damage caused by this insect may compromise up to 100% of crop production, and management of this pest has relied on spraying of synthetic insecticides. However, due to the environmental issues associated with this practice, alternative methods such as the use of botanical pesticides are now used as a strategy of integrated pest management (IPM). We evaluated the effects of essential oils of five plant species on B. tabaci biotype B in tomato and demonstrate that the essential oils (0.5%) of Piper callosum (PC-EO), Adenocalymma alliaceum (AA-EO), Pelargonium graveolens (PG-EO), and Plectranthus neochilus (PN-EO) inhibit the settlement and oviposition of B. tabaci biotype B adults in tomato plants. In fumigation tests, A. alliaceum (AA-EO) at 0.4 μL/L of air after 72 h and 0.1 μL/L of air after 6 h was the most effective against nymphs and adults of B. tabaci biotype B, respectively. The major chemical constituents of PC-EO were identified as being safrole (29.3%), α-pinene (19.2%), and β-pinene (14.3%), whereas diallyl trisulfide (66.9%) and diallyl disulfide (23.3%) were the major compounds identified in AA-EO. This is the first report on the reduction of oviposition by the use of P. callosum (PC-EO) and A. alliaceum (AA-EO). In addition, the fumigant effect of A. alliaceum (AA-EO) on nymphs and adults has also been reported here for the first time.

  12. The suitability of biotypes Q and B of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) at different nymphal instars as hosts for Encarsia formosa Gahan (Hymenoptera: Aphelinidae)

    Science.gov (United States)

    Liu, Xin; Zhang, Youjun; Xie, Wen; Wu, Qingjun

    2016-01-01

    Encarsia formosa Gahan (Hymenoptera: Aphelinidae) is a solitary endoparasitoid that is commercially reared and released for augmentative biological control of whiteflies infesting greenhouse crops. In most areas in China, the invasive and destructive whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) biotype Q has replaced B. tabaci biotype B and has become dominant between the two. A better understanding of the suitability of different nymphal instars of B. tabaci biotypes Q and B as hosts for E. formosa is needed to improve the use of this parasitoid for biological control. Parasitism of the four nymphal instars of B. tabaci biotypes Q and B by the commercial strain of E. formosa mass reared on Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) was assessed in the laboratory. The results indicated that E. formosa parasitized and successfully developed on all instars of both biotypes but performed best on the 3rd instar of B. tabaci biotype B and on the 2nd, 3rd, and 4th instars of B. tabaci biotype Q. The host-feeding rate of the adult parasitoid was generally higher on nymphal instars of B. tabaci biotype Q than on the corresponding nymphal instars of biotype B and was significantly higher on the 2nd and 3rd instars. For both whitefly biotypes, the parasitoid’s immature developmental period was the longest on the 1st instar, intermediate on the 2nd and 3rd instars, and the shortest on the 4th instar. The parasitoid emergence rate was significantly lower on the 1st instar than on the other three instars and did not significantly differ between B. tabaci biotype B and biotype Q. Offspring longevity was greater on the 3rd and 4th instars than on the 1st instar and did not significantly differ between the two B. tabaci biotypes. The results indicate that commercially-produced E. formosa can parasitize all instars of B. tabaci biotypes B and Q, making this parasitoid a promising tool for the management of the two biotypes of B. tabaci present

  13. The suitability of biotypes Q and B of Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae at different nymphal instars as hosts for Encarsia formosa Gahan (Hymenoptera: Aphelinidae

    Directory of Open Access Journals (Sweden)

    Xin Liu

    2016-04-01

    Full Text Available Encarsia formosa Gahan (Hymenoptera: Aphelinidae is a solitary endoparasitoid that is commercially reared and released for augmentative biological control of whiteflies infesting greenhouse crops. In most areas in China, the invasive and destructive whitefly Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae biotype Q has replaced B. tabaci biotype B and has become dominant between the two. A better understanding of the suitability of different nymphal instars of B. tabaci biotypes Q and B as hosts for E. formosa is needed to improve the use of this parasitoid for biological control. Parasitism of the four nymphal instars of B. tabaci biotypes Q and B by the commercial strain of E. formosa mass reared on Trialeurodes vaporariorum (Westwood (Hemiptera: Aleyrodidae was assessed in the laboratory. The results indicated that E. formosa parasitized and successfully developed on all instars of both biotypes but performed best on the 3rd instar of B. tabaci biotype B and on the 2nd, 3rd, and 4th instars of B. tabaci biotype Q. The host-feeding rate of the adult parasitoid was generally higher on nymphal instars of B. tabaci biotype Q than on the corresponding nymphal instars of biotype B and was significantly higher on the 2nd and 3rd instars. For both whitefly biotypes, the parasitoid’s immature developmental period was the longest on the 1st instar, intermediate on the 2nd and 3rd instars, and the shortest on the 4th instar. The parasitoid emergence rate was significantly lower on the 1st instar than on the other three instars and did not significantly differ between B. tabaci biotype B and biotype Q. Offspring longevity was greater on the 3rd and 4th instars than on the 1st instar and did not significantly differ between the two B. tabaci biotypes. The results indicate that commercially-produced E. formosa can parasitize all instars of B. tabaci biotypes B and Q, making this parasitoid a promising tool for the management of the two biotypes of B

  14. Caracterización in silico de las proteínas del choque térmico Hsp70 y Hsp90 deBemisia tabaci (Hemiptera: Aleyrodidae) y su posible actividad adaptativa

    OpenAIRE

    Eneida Torres Cabra; Javier Hernández-Fernández

    2014-01-01

    La mosca blanca, Bemisia tabaci (Hemiptera: Aleyrodidae) es una de las plagas más destructivas e invasivas en el mundo, ataca una gran cantidad de cultivos. Se adapta fácilmente a plantas hospederas y a nuevas regiones geográficas, lo que sugiere el desarrollo de mecanismos de control a daños producidos por factores estresantes. Las proteínas Hsp se expresanen los organismos como mecanismo de defensa, actúan como chaperonas en el correcto ensamblaje de las proteínas. En este estudio se realiz...

  15. Variation in Eastern cottonwood (Populus deltoides Bartr.) phloem sap content caused by leaf development may affect feeding site selection behavior of the aphid, Chaitophorous populicola Thomas (Homoptera: Aphididae).

    Science.gov (United States)

    Gould, Georgianna G; Jones, Clive G; Rifleman, Peggy; Perez, Antonio; Coleman, James S

    2007-10-01

    Apterous populations of Chaitophorous populicola Thomas (Homoptera: Aphididae) appear to track Eastern cottonwood (Populus deltoides Bartr.) leaf development. Few aphids occur on mature leaves. Marked individual aphids on leaves of different developmental stages were observed through a period of new leaf initiation. Nymph and adult C. populicola frequently track leaf development by moving up to younger leaves. A comparison of phloem sap constituents and leaf toughness among leaf developmental stages revealed some differences that could be used by C. populicola to determine leaf age. Phloem sap exudates, collected from P. deltoides leaves of different developmental stages, were analyzed by high-performance liquid chromatography for free amino acids and the phenolic glycoside salicin. Sucrose concentration in exudates, indicative of phloem sap exudation rate, was uniform among leaf stages. Of 20 amino acids examined, only aspartic acid and gamma-amino-n-butyric acid (GABA) concentrations differed significantly between leaf stages. Forward stepwise discriminant function analysis showed that seven of the amino acids analyzed are useful for classifying leaf maturity groupings. Aphid-infested cottonwoods had lower cystine concentrations in phloem sap than aphid-free plants. Salicin concentration was significantly higher in new leaves. Leaf toughness was assessed by lignin density and distance measurements in petiole cross-sections. Rapidly expanding leaves had significantly less lignification and new leaves had shorter distances to the vascular bundles than senescent leaves. These physiological and phytochemical differences among P. deltoides leaf developmental stages may contribute to the leaf stage selection patterns exhibited by the aphid, C. populicola.

  16. Dinâmica Populacional de Mosca-Branca Bemisia tabaci (Genn. Biótipo B (Hemiptera: Aleyrodidae em Feijoeiro

    Directory of Open Access Journals (Sweden)

    Anderson Silva

    2014-04-01

    Abstract. This study aimed to evaluate the influence of abiotic factors on the population dynamics of the whitefly Bemisia tabaci (Genn., (Hemiptera: Aleyrodidae in three sowing seasons on bean plants (Phaseolus vulgaris L.. The assays were set up from June 2010 to April 2012 and conducted in the Departamento de Fitossanidade at FCAV/UNESP – Campus of Jaboticabal, SP. The studies of the population dynamics of B. tabaci biotype B were performed weekly through infestation assessments of eggs, nymphs and adults of the whitefly on 18 samplings, six for each sowing season: “winter”, “water” and “dry”, in addition to the influence of the abiotic factors weekly temperature and relative humidity (minimum, average and maximum and accumulated rainfall. These variables were correlated to the total number of eggs, nymphs and adults of the whitefly through Pearson’s linear correlation analysis. Among the obtained results, the population peaks of B. tabaci biotype B occurred at the “water” season, followed by “winter” and “dry” seasons, and the abiotic factors temperature and relative humidity influenced negatively the population dynamics of the whitefly.

  17. New putative cryptic species detection and genetic network analysis of Bemisia tabaci (Hempitera: Aleyrodidae) in China based on mitochondrial COI sequences.

    Science.gov (United States)

    Hu, Jian; Zhang, Xiaoyun; Jiang, Zhilin; Zhang, Feifei; Liu, Yuanyuan; Li, Zhan; Zhang, Zhongkai

    2017-04-01

    The whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a cryptic species complex and widely distributed throughout tropical and subtropical regions. To understand the B. tabaci cryptic species diversity in China more comprehensively, in the year 2014 and 2016, a large-scale sampling was conducted from the famous biodiversity hotspot of China, Yunnan province. Mitochondrial cytochrome oxidase I gene sequences were used to identify new putative cryptic species. Phylogenetic analyses were performed using Bayesian methods to evaluate the position of new cryptic species in the context of the B. tabaci diversity in Asia. Two new cryptic species, China 5 and Asia V were identified. In total, 19 B. tabaci cryptic species are present in China, two invasive (MED and MEAM1) and 17 indigenous. A new sibling species of B. tabaci was first defined and reported. Based on the mtCOI sequences and haplotype network analyses, the genetic diversity of MED was far higher than MEAM1. We confirmed the exotic MED was originated from the western Mediterranean regions and first invaded into Yunnan, China. The genetic structures of other four indigenous species (Asia I, Asia II 1, Asia II 6, and China 1) with relatively wide distribution ranges in China were also discussed.

  18. Age Stage Two-Sex Life Table Reveals Sublethal Effects of Some Herbal and Chemical Insecticides on Adults of Bemisia tabaci (Hem.: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Fatemeh Jafarbeigi

    2014-01-01

    Full Text Available The sweetpotato whitefly, Bemisia tabaci (Genn. (Hem.: Aleyrodidae, is an important pest of agriculture in subtropical and tropical areas. In this study, we used the age-stage two-sex life table to evaluate the sublethal effects of the herbal extracts taken from Fumaria parviflora Lam. (Fumariaceae, Teucrium polium L. (Lamiaceae, Calotropis procera (Willd. R. Br. (Asclepiadaceae, and Thymus vulgaris L. (Lamiaceae as well as the two commercial synthetic insecticides, pymetrozin and neemarin. The whiteflies were exposed to each insecticide using leaf-dip method. Analysis of life table parameters revealed significant differences (P≤0.05 in the net reproductive rate (R0, NRR, intrinsic rate of increase (rm, and finite rate of increase (λ among different insecticides. The lowest values of the three population parameters, R0, r, and λ, were observed on whiteflies treated with pymetrozin (2.455, 0.036, and 1.036, T. polium (2.828, 0.044, and 1.045, and neemarin (2.998, 0.046, and 1.047, respectively. Results of this study highlights the satisfactory insecticidal effects of the extract taken from T. polium on B. tabaci, which is comparable to the two commonly used synthetic insecticides.

  19. Diseño de planes de muestreo con niveles fijos de precisión del pulgón manchado de la alfalfa, Therioaphis trifolii Monell (Homoptera: Aphididae) en alfalfa (Medicago sativa L.)

    OpenAIRE

    Gyenge, Javier E.; Trumper, Eduardo V.; Edelstein, Julio D.

    1999-01-01

    El objetivo de este trabajo fue construir planes secuenciales de muestreo para el pulgón manchado de la alfalfa, Therioaphis trifolii Monell (Homoptera: Aphididae), con niveles fijos de precisión para estimar su densidad en función de toma de decisiones. El estudio de la disposición espacial basado en la Ley de Potencia de Taylor y regresión de Iwao, indicó que esta especie se distribuye de manera agregada en el cultivo de alfalfa, aunque con diferentes grados de agregación según el estado de...

  20. Understanding biological control of greenhouse whitefly with the parasitoid Encarsia formosa : from individual behaviour to population dynamics

    NARCIS (Netherlands)

    Roermund, van H.J.W.

    1995-01-01

    The greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Homoptera, Aleyrodidae), is a very common, highly polyphagous pest insect all over the world. Biological control of whiteflies with the parasitoid Encarsia formosa Gahan (Hymenoptera,

  1. Author Details

    African Journals Online (AJOL)

    Spread of the spiraling white fly Aleurodicus dispersus (Homoptera: Aleyrodidae) and its parasitoids Encarcia species (Hymenoptera: Aphelinidae) on horticultural plants in Northwest and Central Nigeria Abstract · Vol 13, No 1 (2008) - Articles A Survey of Rootstock Usage and their Influence on Major Insects and Diseases ...

  2. Author Details

    African Journals Online (AJOL)

    Ewusie, EA. Vol 17, No 1 (2010) - Articles Strip Cropping: A Potential IPM Tool for Reducing Whitefly, Bemisia tabaci Gennadius (Homoptera: Aleyrodidae) Infestations in Cassava Abstract PDF. ISSN: 0855-4307. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More ...

  3. Isolation, genetic diversity and identification of a virulent pathogen of ...

    African Journals Online (AJOL)

    AJL

    bassiana against Tetranychus urticae (Koch). Scientia Agricola. 56:285-288. Tuite AM (1969). Use of Beauveria bassiana (Bals) to control the immature stages of the whitefly, Trialeurodes vaporariorum. (Westwood) (Homoptera: Aleyrodidae) in the greenhouse. Arab. J. Plant Prot. 2:83-86. Van leeuwen T, Nauen R, Witters J ...

  4. Effect of elevated CO2 concentration and temperature on antioxidant capabilities of multiple generations of Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Li, Ning; Li, Yaohua; Zhang, Shize; Fan, Yongliang; Liu, Tongxian

    2017-10-19

    A rise in atmospheric carbon dioxide concentration ([CO2]) and a warming climate are two of the most conspicuous characteristics of global climate change in this century. However, studies addressing the combined impact of rising [CO2] and temperature on herbivore insect physiology are still limited. In this study we investigated the combined effects of elevated [CO2] and temperature on major antioxidative enzymes, including superoxide dismutase (SOD), catalase (CAT), peroxidases (POD) and detoxification enzymes of glutathione-S-transferases (GST) and acetylcholinesterase (AChE) in three consecutive generations of Bemisia tabaci Middle East-Asia Minor 1 (MEAM1, commonly known as B biotype) adults. The results indicated that the antioxidant capabilities of B. tabaci differed significantly during different treatments across different generations. Elevated [CO2] markedly increased POD, GST and AChE activities in the first generation, and SOD, CAT and GST activities in the second generation, but reduced POD activity in the third generation at ambient temperature. Under elevated temperature, elevated [CO2] significantly increased GST and AChE activities in the first generation and CAT activity in the third generation, reduced SOD activity in the third generation and reduced AChE activity in the second generation. [CO2], temperature and insect generation interacted to affect the antioxidant capabilities of B. tabaci. These results suggest both that changes in antioxidant capabilities vary in response to either [CO2] or temperature, or a combination of both, leading to oxidative stress and also that antioxidant enzymes play important roles in reducing oxidative damage in B. tabaci. Changes in the exposure of antioxidant compounds over the course of three generations suggest that acclimation and/or adaptation to elevated [CO2] and temperature may have occurred. This study represents the first comprehensive report on the antioxidant defense mechanism in successive multiple

  5. Ocorrência de Tuthillia cognata Hodkinson, Brown & Burckhardt, 1986(Hemiptera: Homoptera, Psyllidae em plantios experimentais de camu-camu Myrciaria dubia (H.B.K. Mc Vaugh em Manaus (Amazonas, Brasil Occurrence of Tuthillia cognata Hodkinson, Brown & Burckhardt, 1986 (Hemiptera: Homoptera, Psyllidae in experimental plantations of camu-camu Myrciaria dubia (H.B.K. Mc Vaugh in Manaus (Amazonas, Brazil

    Directory of Open Access Journals (Sweden)

    Márcio Luís Leitão Barbosa

    2004-01-01

    Full Text Available O cultivo de camu-camu Myrciaria dubia (H.B.K. Mc Vaugh tem apresentado inúmeros problemas fitossanitários, dentre os quais, Tuthillia cognata Hodkinson et al. (Hemiptera: Homoptera, Psyllidae, que constantemente é citada como praga secundária. Os objetivos deste estudo foram determinar o nível e a intensidade de infestação (% por T. cognata e estudar aspectos do ciclo biológico e do comportamento de T. cognata, em plantios experimentais de camu-camu. Foram selecionados, de forma aleatória, 17 e 14 exemplares nos plantios I e II, respectivamente. Para cada uma das variáveis estudadas, foram calculados a média aritmética, o desviopadrão, a variância e a amplitude de variação. Foi verificado um nível de infestação de 82% (plantio I e 57% (plantio II, uma intensidade de infestação de 94% (plantio I e 75% (plantio II e uma média de seis ninfas/folha em cada plantio, o que indica que T. cognata representa uma das pragas-chave dessa cultura. Foram observados adultos de Chrysoperla sp. (Neuroptera: Chrysopidae e ninfas de Reduviidae (Hemiptera: Heteroptera, que podem atuar como prováveis agentes de controle biológico de T. cognata.The cultivation of camu-camu Myrciaria dubia (H.B.K. Mc Vaugh has presented countless phytosanitary problems, among them, Tuthillia cognata Hodkinson et al. (Hemiptera: Homoptera, Psyllidae, which often is noticed as a secondary pest. This study aimed to determine the level and the intensity of infestation (% for T. cognata, as well as to study the biological cycle and behavioural aspects of T. cognata, in experimental plantation of camu-camu. 17 and 14 specimens from plantation I and II, respectively, were randomly selected. The arithmetic average, the standard deviation, the variance and the total amplitude were calculated for each studied variable. A level of infestation of 82% (plantation I and 57% (plantation II, an intensity of infestation of 94% (plantation I and 75% (plantation II and an

  6. Phylogenetic position of the yeast-like symbiotes of Tagosodes orizicolus (Homoptera: Delphacidae based on 18S ribosomal DNA partial sequences

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    Ana M Xet-Mull

    2004-09-01

    Full Text Available Tagosodes orizicolus Muir (Homoptera: Delphacidae, the endemic delphacid species of tropical America carries yeast-like symbiotes (YLS in the abdominal fat bodies and the ovarial tissues, like other rice planthoppers of Asia. These YLS are obligate symbiotes, which are transmitted transovarially, and maintain a mutualistic relationship with the insect host. This characteristic has made in vitro culture and classification of YLS rather difficult using conventional methods. Nevertheless, microorganisms of similar characteristics have been successfully classified by using molecular taxonomy. In the present work, the YLS of Tagosodes orizicolus(YLSTo were purified on Percoll® gradients, and specific segments of 18S rDNA were amplified by PCR, cloned and sequenced. Sequences were aligned by means of the CLUSTAL V (DNASTAR program; phylogenetic trees were constructed with the Phylogeny Inference Package (PHYLIP, showing that YLSTo belong to the fungi class Pyrenomycetes, phylum Ascomycota. Similarities between 98% and 100% were observed among YLS of the rice delphacids Tagosodes orizicolus, Nilaparvata lugens, Laodelphax striatellus and Sogatella furcifera, and between 89.8% and 90.8% when comparing the above to YLS of the aphid Hamiltonaphis styraci. These comparisons revealed that delphacid YLS are a highly conserved monophyletic group within the Pyrenomycetes and are closely related to Hypomyces chrysospermus. Rev. Biol. Trop. 52(3: 777-785. Epub 2004 Dic 15.Tagosodes orizicolus Muir (Homoptera: Delphacidae es una especie endémica de América tropical que al igual que otros saltahojas de Asia, tiene simbiontes levaduriformes (YLS, por sus siglas en Inglés en los cuerpos grasos del abdomen y en los tejidos de los ovarios. Los YLS son simbiontes obligados que se transmiten transovarialmente y que mantienen relaciones mutualística con el insecto hospedero. Esta característica ha hecho muy difícil su cultivo in vitro y por ende su clasificaci

  7. Improved DNA barcoding method for Bemisia tabaci and related Aleyrodidae: development of universal and Bemisia tabaci biotype-specific mitochondrial cytochrome c oxidase I polymerase chain reaction primers.

    Science.gov (United States)

    Shatters, Robert G; Powell, Charles A; Boykin, Laura M; Liansheng, He; McKenzie, C L

    2009-04-01

    Whiteflies, heteropterans in the family Aleyrodidae, are globally distributed and severe agricultural pests. The mitochondrial cytochrome c oxidase I (mtCOI) sequence has been used extensively in whitefly phylogenetic comparisons and in biotype identification of the agriculturally important Bemisia tabaci (Gennadius) whitefly. Because of the economic importance of several whitefly genera, and the invasive nature of the B and the Q biotypes of Bemisia tabaci, mtCOI sequence data are continually generated from sampled populations worldwide. Routine phylogenetic comparisons and biotype identification is done through amplification and sequencing of an approximately 800-bp mtCOI DNA fragment. Despite its routine use, published primers for amplification of this region are often inefficient for some B. tabaci biotypes and especially across whitefly species. Through new sequence generation and comparison to available whitefly mtCOI sequence data, a set of polymerase chain reaction (PCR) amplification primers (Btab-Uni primers) were identified that are more efficient at amplifying approximately 748 bp of the approximately 800-bp fragment currently used. These universal primers amplify an mtCOI fragment from numerous B. tabaci biotypes and whitefly genera by using a single amplification profile. Furthermore, mtCOI PCR primers specific for the B, Q, and New World biotypes of B. tabaci were designed that allow rapid discrimination among these biotypes. These primers produce a 478-, 405-, and 303-bp mtCOI fragment for the B, New World, and Q biotypes, respectively. By combining these primers and using rapid PCR and electrophoretic techniques, biotype determination can be made within 3 h for up to 96 samples at a time.

  8. Leaf Morphological Characters Can Be a Factor for Intra-Varietal Preference of Whitefly Bemisia tabaci (Hemiptera: Aleyrodidae among Eggplant Varieties.

    Directory of Open Access Journals (Sweden)

    Abu Tayeb Mohammad Hasanuzzaman

    Full Text Available The sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae MEAM1, is considered a serious pest of horticultural and many other crops. While eggplant (Solanum melongena is one of the most favored host plants, the whiteflies exhibit preferences among different varieties. We hypothesized that certain morphological leaf characteristics of different varieties, like leaf trichome density, trichome length, leaf lamina thickness and leaf color, may affect whitefly landing, feeding and oviposition. In this study, we investigated the variation in leaf morphological characters among selected eggplant varieties and evaluated the effect of these leaf characteristics in rendering eggplant varieties either susceptible or resistant to B. tabaci. We evaluated eight eggplant varieties in choice feeding tests, and we found that the varieties JinSheng Zilongchangqie (JSZ and H149 were the highly preferred varieties with the highest numbers of whitefly adults and eggs. Significantly lower numbers of whitefly adult eggs were found on the resistant variety Tuo Lu Bamu (TLB. The varieties JinGuangbo Luqie (JGL, JinGuangbo Ziquanqie (JGZ, DaYang Ziguanqie (DYZ, QinXing Ziguanqie (QXZ, and QinXing Niuxinqie (QXN were moderately favored by B. tabaci. Leaf trichome density, trichome length and leaf lamina thickness were positively correlated with numbers of whitefly adults and eggs. B. tabaci was less attracted to the leaves that reflect long and middle wavelength light (higher R and G values than to the bright green leaves (medium G value, but the short wavelength light (higher B value had no significant effect on whitefly preference. The degree of hue had a positive effect, and saturation and brightness had a negative effect on whitefly attraction.

  9. Leaf Morphological Characters Can Be a Factor for Intra-Varietal Preference of Whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) among Eggplant Varieties

    Science.gov (United States)

    Zhang, Yi; Zhang, Chen-Yang; Liu, Tong-Xian

    2016-01-01

    The sweetpotato whitefly, Bemisia tabaci (Hemiptera: Aleyrodidae) MEAM1, is considered a serious pest of horticultural and many other crops. While eggplant (Solanum melongena) is one of the most favored host plants, the whiteflies exhibit preferences among different varieties. We hypothesized that certain morphological leaf characteristics of different varieties, like leaf trichome density, trichome length, leaf lamina thickness and leaf color, may affect whitefly landing, feeding and oviposition. In this study, we investigated the variation in leaf morphological characters among selected eggplant varieties and evaluated the effect of these leaf characteristics in rendering eggplant varieties either susceptible or resistant to B. tabaci. We evaluated eight eggplant varieties in choice feeding tests, and we found that the varieties JinSheng Zilongchangqie (JSZ) and H149 were the highly preferred varieties with the highest numbers of whitefly adults and eggs. Significantly lower numbers of whitefly adult eggs were found on the resistant variety Tuo Lu Bamu (TLB). The varieties JinGuangbo Luqie (JGL), JinGuangbo Ziquanqie (JGZ), DaYang Ziguanqie (DYZ), QinXing Ziguanqie (QXZ), and QinXing Niuxinqie (QXN) were moderately favored by B. tabaci. Leaf trichome density, trichome length and leaf lamina thickness were positively correlated with numbers of whitefly adults and eggs. B. tabaci was less attracted to the leaves that reflect long and middle wavelength light (higher R and G values) than to the bright green leaves (medium G value), but the short wavelength light (higher B value) had no significant effect on whitefly preference. The degree of hue had a positive effect, and saturation and brightness had a negative effect on whitefly attraction. PMID:27081849

  10. Susceptibility of MED-Q1 and MED-Q3 Biotypes of Bemisia tabaci (Hemiptera: Aleyrodidae) Populations to Essential and Seed Oils.

    Science.gov (United States)

    Samuel Fogné, Drabo; Olivier, Gnankine; Bassolé, Imael H N; Nébié, Roger Charles; Laurence, Mouton

    2017-06-01

    Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) is a major pest of many agricultural and ornamental crops in tropical and subtropical regions causing damages that result in important economic losses. Insecticides are commonly used in greenhouses or fields to control B. tabaci populations leading to rapid evolution of resistance that render treatments inefficient. Therefore, and for environmental and human health concerns, other approaches must be developed for this pest management. In the present study, we compare, using the leaf dip method, the toxicity of three essential oils (Cymbopogon citratus, Ocimum americanum, and Hyptis spicigera) and three seed oils (Lannea microcarpa, Lannea acida, and Carapa procera) with three chemical insecticides (acetamiprid, deltamethrin, and chlorpyrifos-ethyl) on adults. Two B. tabaci biotypes (MED-Q1 and MED-Q3) belonging to the Mediterranean species and collected in Burkina Faso were used. Essential oils were analyzed by gas chromatography-mass spectrometry and gas chromatography-flame ionization detector. We showed that these two biotypes have different levels of resistance to the three insecticides, MED-Q3 being more sensitive than MED-Q1. Moreover, they differ in the frequency of resistance alleles to insecticides, especially for organophosphates, as these alleles are almost fixed in MED-Q1. On the other hand, the two biotypes prove to be more susceptible to the plant extracts than to insecticides except for chlorpyrifos-ethyl, with essential oils that showed the highest insecticidal activities. Monoterpenes content were the most abundant and showed the highest insecticidal activities. Our results indicated that essential oils, but also seed oils, have the potential to constitute an alternative strategy of pest management. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. The Effects of Some Botanical Insecticides and Pymetrozine on Life Table Parameters of Silver Leaf Whitefly Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Reihaneh Barati

    2013-01-01

    Full Text Available The objective of this research was to assess the effects of extracts of two medicinalplant species: Allium sativum (Linn and Calotropis procera (Aiton, and a formulation containingazadirachtin on life table parameters of silver leaf whitefly (SLW, Bemisia tabaci biotypeB (Gennadius (Hemiptera: Aleyrodidae, grown on greenhouse tomato plants. Theeffects were compared to that of pymetrozine, a synthetic insecticide. Bioassays were carriedout in a greenhouse under controlled conditions of 27 ± 2°C, R.H. of 55 ± 5% and 16:8h (L:D photo period.All treatments significantly affected the survivorship and fertility of SLW female adults,reducing the net reproduction rate, mean generation time and intrinsic rate of increase ofthis insect.The net reproductive rate [R0] values for the populations treated with garlic extract,milkweed extract, pymetrozine, azadirachtin, control for extracts (ethanol + distilled waterand control for pesticides (distilled water were 23.58, 19.32, 10.78, 8.23, 49.66, 57.55; theintrinsic rate of increases [rm] were 0.134, 0.139, 0.110, 0.090, 0.177, 0.178; the mean generationtimes [T] were 23.49, 21.23, 21.66, 23.50, 22.06, 22.69; the doubling times [DT] were 5.14,4.95, 6.27, 7.56, 3.91, 3.87, and the finite rates of increase [λ] were 1.144, 1.149, 1.116, 1.094, 1.193,1.195, respectively. Azadirachtin had the highest effect on the life table parameters of SLW.Our findings indicated that, although herbal extracts were not effective as much asthe chemical insecticides, they can be effective in pest control. Therefore, they are suitablechoices for replacing chemical insecticides and for alternative use with azadirachtin inSLW IPM program.

  12. Contribution à l'étude de l'écologie et de la biologie des homoptères ravageurs des arbres fruitiers et autres plantes I.- Comparaison de l'évolution des populations d'Aleurodicus dispersus Russell (Hom.: Aleyrodidae) sur agrumes et avocatier en République du Congo

    OpenAIRE

    Kiyindou, A.

    2002-01-01

    Contribution to the Knowledge of the Ecology and Biology of Homopterous Pests of Fruit Trees and other Plants I.- Comparaison of Evolution of Population of Aleurodicus dispersus Russell (Hom.: Aleyrodidae) on Citrus and Avocado Trees in the Republic of the Congo. Aleurodicus dispersus Russell, a whitefly of neotropical origin, was introduced into Congo in the early '90. Since 1995, A. dispersus has developped the important populations on Citrus and avocado trees. The study of the population d...

  13. Genetic variation of the greenhouse whitefly, Trialeurodes vaporariorum (Hemiptera: Aleyrodidae), among populations from Serbia and neighbouring countries, as inferred from COI sequence variability.

    Science.gov (United States)

    Prijović, M; Skaljac, M; Drobnjaković, T; Zanić, K; Perić, P; Marčić, D; Puizina, J

    2014-06-01

    The greenhouse whitefly Trialeurodes vaporariorum Westwood, 1856 (Hemiptera: Aleyrodidae) is an invasive and highly polyphagous phloem-feeding pest of vegetables and ornamentals. Trialeurodes vaporariorum causes serious damage due to direct feeding and transmits several important plant viruses. Excessive use of insecticides has resulted in significantly reduced levels of susceptibility of various T. vaporariorum populations. To determine the genetic variability within and among populations of T. vaporariorum from Serbia and to explore their genetic relatedness with other T. vaporariorum populations, we analysed the mitochondrial cytochrome c oxidase I (COI) sequences of 16 populations from Serbia and six neighbouring countries: Montenegro (three populations), Macedonia (one population) and Croatia (two populations), for a total of 198 analysed specimens. A low overall level of sequence divergence and only five variable nucleotides and six haplotypes were found. The most frequent haplotype, H1, was identified in all Serbian populations and in all specimens from distant localities in Croatia and Macedonia. The COI sequence data that was retrieved from GenBank and the data from our study indicated that H1 is the most globally widespread T. vaporariorum haplotype. A lack of spatial genetic structure among the studied T. vaporariorum populations, as well as two demographic tests that we performed (Tajima's D value and Fu's Fs statistics), indicate a recent colonisation event and population growth. Phylogenetic analyses of the COI haplotypes in this study and other T. vaporariorum haplotypes that were retrieved from GenBank were performed using Bayesian inference and median-joining (MJ) network analysis. Two major haplogroups with only a single unique nucleotide difference were found: haplogroup 1 (containing the five Serbian haplotypes and those previously identified in India, China, the Netherlands, the United Kingdom, Morocco, Reunion and the USA) and haplogroup 3

  14. Efeito inseticida sistêmico de nanoformulações à base de nim sobre Bemisia tabaci (Hemiptera: Aleyrodidae biótipo B em tomateiro

    Directory of Open Access Journals (Sweden)

    Sheila Salles de Carvalho

    2015-01-01

    Full Text Available Este estudo avaliou a ação inseticida sistêmica e o efeito residual de nanoformulações à base de derivados de nim (Azadirachta indica A. Juss, Meliaceae sobre ninfas de Bemisia tabaci biótipo B (Hemiptera: Aleyrodidae, espécie-praga de diversas culturas de importância econômica. Suspensões coloidais contendo nanocápsulas carregadas com produtos derivados de A. indica foram preparadas utilizando polímeros biodegradáveis como poli-ε-caprolactona (PCL e poli-β-hidroxibutirato (PHB. A matriz encapsulada era composta por uma formulação comercial contendo uma quantidade enriquecida e conhecida dos limonoides azadiractina e 3-tigloilazadiractol (Azamax® 1,2 CE. Inicialmente foi estimada a CL50, para ninfas de B. tabaci, de soluções contendo óleo de nim, que foram aplicadas via água de irrigação (solo em tomateiro. Posteriormente, dois lotes de nanoformulações, com variação no tipo e quantidade dos polímeros e na quantidade do óleo comercial, foram testados quanto à ação sistêmica. As nanoformulações NC L5-2 (com nanocápsulas de PCL e NC L6-1 (com nanocápsulas de PHB, as mais eficazes entre as testadas, foram avaliadas quanto ao efeito residual. A CL50 estimada foi de 180,67 mg L–1 de azadiractina. Constatou-se também que a ação sistêmica de óleos e nanoformulações contendo compostos de nim dependem das condições ambientais em que são aplicados. O Azamax® não apresenta efeito deterrente sobre a oviposição, nem age sobre o desenvolvimento embrionário da mosca-branca quando aplicado via água de irrigação no solo no momento da infestação. As nanoformulações selecionadas são bioativas mesmo cerca de 30 dias após a aplicação, não diferindo do produto comercial.

  15. Population Growth of Rhopalosiphum padi L. (Homoptera: Aphididae on Different Cereal Crops from the Semiarid Pampas of Argentina under Laboratory Conditions Crecimiento Poblacional de Rhopalosiphum padi L. (Homoptera: Aphididae sobre Diferentes Cereales de la Pampas Semiárida de Argentina en Condiciones de Laboratorio

    Directory of Open Access Journals (Sweden)

    Lilian R Descamps

    2011-09-01

    Full Text Available The bird cherry-oat aphid Rhopalosiphum padi L. (Homoptera: Aphididae is one of the main pests in a number of crops in the semiarid Pampas of Argentina. In the present study, the effect of different host plants, including Triticum aestivum L., ×Triticosecale Wittm., Hordeum vulgare L., Hordeum distichum L., Avena sativa L., and Secale cereale L. on biological parameters of R. padi L. was studied in the laboratory at 24 ± 1 °C, 65 ± 10% RH and a 14:10 photoperiod. Longevity, intrinsic rate of natural increase (r m, net reproductive rate (R0, mean generation time (T, doubling time (DT, and finite rate of increase (λ of the bird cherry-oat aphid on the different cereal crops were estimated. Differences in fertility life table parameters of R. padi among host plants were analyzed using pseudo-values, which were produced by Jackknife re-sampling. Results indicated that beer barley might be the most suitable food for R. padi due to greater adult longevity (20.88 d, higher fecundity (41 nymphs female-1, higher intrinsic rate of natural increase (0.309 females female-1 d-1, lower doubling time (2.24, and lower nymphal mortality (22.2%. Therefore, it can be concluded from the present study that R. padi prefers beer barley for fast and healthy development over other cereal crops.El áfido Rhopalosiphum padi L. (Homoptera: Aphididae es una de las principales plagas de numerosos cultivos de la región semiárida pampeana de Argentina. En el presente trabajo se estudió el efecto de diferentes cereales incluidos Triticum aestivum L., ×Triticosecale Wittm., Hordeum vulgare L., Hordeum distichum L., Avena sativa L. and Secale cereale L. sobre los parámetros biológicos de R. padi en laboratorio. Se estimaron longevidad, tasa intrínseca de crecimiento natural (r m, tasa neta de reproducción (R0, tiempo generacional medio (T, tiempo de duplicación (TD, y tasa finita de incremento (λ del pulgón de la avena en diferentes cereales. Las diferencias de

  16. (dysaphis) foeniculus Theobald (Homoptera: Aphididae)

    African Journals Online (AJOL)

    Ogenga-latigo and lamo-Ayo tor of two tulip viruses), and the fact that the few published reports on the aphid are limited to taxonomic descriptions and brief notes on dis- tribution and host range, the present study was instituted to assess some aspects of its biology when reared on carrots in Uganda. Materials and Methods.

  17. Hormaphidinae from Java (Homoptera: Aphididae)

    NARCIS (Netherlands)

    Noordam, D.

    1991-01-01

    Descriptions are given of 18 genera and 56 species, with keys to the apterae and alatae viviparae. The following new genera and species are described: Astegopteryx glandulosa spec. nov., from Gigantochloa spec. and other bamboos; A. setigera spec. nov., from Styrax benzoin Dryander; Cerataphis

  18. Ecological studies on San José scale, Diaspidiotus perniciosus (Comstock) (Homoptera: Diaspididae) as a new insect pest on pear trees in Burg El-Arab area, Alexandria, Egypt.

    Science.gov (United States)

    Moursi Khadiga, S; Mesbah, H A; Mourad, A K; Abdel-Razak Soad, I

    2008-01-01

    The San José scale, D. perniciosus (Comstock) (Homoptera: Diaspididae) was noticed on pear trees all the year round in Burg El-Arab area (50 km West of Alexandria). Bio ecology and population fluctuations of this serious scale insect were carried out during the two subsequent seasons of September, 2004 until August, 2006. The calculated infestation rates (%) assured the presence of three peaks in both seasons. The estimated densities of fluctuating individuals of D. perniciosus on the inspected pear trees showed two distinctly prominent peaks, in addition to an overlapping one between them. It means, that the San Josè scale, D. perniciosus had three overlapping annual generations on pear trees in Burg El-Arab area under an irrigation system. The individuals of all stages could be found on trees all over the year. The population of the inspected immature stages; adult females and adult males were recorded and discussed as well as the parasitized individuals by the aphilinid parasitoid, Aphytis diaspidis (Howard) (Hymenoptera: Aphelinidae). The population density of the San José scale (SJS) reached its maximum during spring, folLowed by summer, winter, whereas the least percentage was recorded in autumn months. The obtained data showed also variable effects of the prevailing abiotic factors on the dynamical oscillation of (SJS) individuals. The daily mean temperature and the dew point were not the dominant efficient physical factors. On the contrary, it has been proved that there were either significant strong negative or positive relationships between daily relative humidity, wind speed, infestation rate, and population density of this studied insect pest.

  19. Distribuição espacial de Aphis gossypii (Glover (Hemiptera, Aphididae e Bemisia tabaci (Gennadius biótipo B (Hemiptera, Aleyrodidae em algodoeiro Bt e não-Bt Spatial distribution of Aphis gossypii (Glover (Hemiptera, Aphididae and Bemisia tabaci (Gennadius biotype B (Hemiptera, Aleyrodidae on Bt and non-Bt cotton

    Directory of Open Access Journals (Sweden)

    Tatiana Rojas Rodrigues

    2010-03-01

    Full Text Available Distribuição espacial de Aphis gossypii (Glover (Hemiptera, Aphididae e Bemisia tabaci (Gennadius biótipo B (Hemiptera, Aleyrodidae em algodoeiro Bt e não-Bt. O estudo da distribuição espacial de adultos de Bemisia tabaci e de Aphis gossypii nas culturas do algodoeiro Bt e não-Bt é fundamental para a otimização de técnicas de amostragens, além de revelar diferenças de comportamento de espécies não-alvo dessa tecnologia Bt entre as duas cultivares. Nesse sentido, o experimento buscou investigar o padrão da distribuição espacial dessas espécies de insetos no algodoeiro convencional não-Bt e no cultivar Bt. As avaliações ocorreram em dois campos de 5.000 m² cada, nos quais se realizou 14 avaliações com contagem de adultos da mosca-branca e colônias de pulgões. Foram calculados os índices de agregação (razão variância/média, índice de Morisita e Expoente k da Distribuição Binomial Negativa e realizados os testes ajustes das classes numéricas de indivíduos encontradas e esperadas às distribuições teóricas de freqüência (Poisson, Binomial Negativa e Binomial Positiva. Todas as análises mostraram que, em ambas as cultivares, a distribuição espacial de B. tabaci ajustou-se a distribuição binomial negativa durante todo o período analisado, indicando que a cultivar transgênica não influenciou o padrão de distribuição agregada desse inseto. Já com relação às análises para A. gossypii, os índices de agregação apontaram distribuição agregada nas duas cultivares, mas as distribuições de freqüência permitiram concluir a ocorrência de distribuição agregada apenas no algodoeiro convencional, pois não houve nenhum ajuste para os dados na cultivar Bt. Isso indica que o algodão Bt alterou o padrão normal de dispersão dos pulgões no cultivo.The study of spatial distribution of the adults of Bemisia tabaci and the colonies of Aphis gossypii on Bt and non-Bt cotton crop is fundamental for

  20. Contribution à l'étude de l'écologie et de la biologie des homoptères ravageurs des arbres fruitiers et autres plantes I.- Comparaison de l'évolution des populations d'Aleurodicus dispersus Russell (Hom.: Aleyrodidae sur agrumes et avocatier en République du Congo

    Directory of Open Access Journals (Sweden)

    Kiyindou, A.

    2002-01-01

    Full Text Available Contribution to the Knowledge of the Ecology and Biology of Homopterous Pests of Fruit Trees and other Plants I.- Comparaison of Evolution of Population of Aleurodicus dispersus Russell (Hom.: Aleyrodidae on Citrus and Avocado Trees in the Republic of the Congo. Aleurodicus dispersus Russell, a whitefly of neotropical origin, was introduced into Congo in the early '90. Since 1995, A. dispersus has developped the important populations on Citrus and avocado trees. The study of the population dynamic of this whitefly on Citrus and avocado trees indicates that the pest exhibits only four and three generation a year on Citrus and avocado trees respectively. Besides, an increase of the population of A. dispersus occurs in the dry season. However, rainfall reduces the insect population to a very low level. Its abundance indicates that during the rainy season, A. dispersus appears ealier underpinned for the first time and its significance assessed.

  1. Caracterización in silico de las proteínas del choque térmico Hsp70 y Hsp90 deBemisia tabaci (Hemiptera: Aleyrodidae y su posible actividad adaptativa

    Directory of Open Access Journals (Sweden)

    Eneida Torres Cabra

    2014-06-01

    Full Text Available La mosca blanca, Bemisia tabaci (Hemiptera: Aleyrodidae es una de las plagas más destructivas e invasivas en el mundo, ataca una gran cantidad de cultivos. Se adapta fácilmente a plantas hospederas y a nuevas regiones geográficas, lo que sugiere el desarrollo de mecanismos de control a daños producidos por factores estresantes. Las proteínas Hsp se expresanen los organismos como mecanismo de defensa, actúan como chaperonas en el correcto ensamblaje de las proteínas. En este estudio se realizó una caracterizaciónin silico de las proteínas Hsp70 y Hsp90 de B. tabaci, secuencias obtenidas de NCBI. La determinaciónde los perfiles de hidrofobicidad, polaridad, accesibilidady flexibilidad se obtuvieron con “ProScale” de ExPASy, el perfil de antigenicidad con JaMBW. La secuencia aminoacídica se analizó con GOR IV y SOPMA y la composición de aminoácidos con ProtParam. Para analizar el peso molecular, índice deinestabilidad, índice alifático y gradiente hidropático,con GRAVY. La estructura terciaria se obtuvo con HHpred, y ESyPred3D. Para validar las estructuras 3D se utilizó Procheck, What_check y errat. Hsp70 y Hsp90 de B. tabaci presentan valores bajos de hidrofobicidady altos de polaridad, flexibilidad y accesibilidad, características que le permiten a las proteínas extender su capacidad como chaperonas. La Hsp70tiene una estructura secundaria compuesta por 41-45% alfa hélices, 30-43% coil y menos del 6% en hoja plegada y la Hsp90 por 52 y 53% hélices, 26-34% coily 6% hoja plegada. Las Hsp juegan un rol importante en los insectos debido a su tamaño y corto ciclo de vida, pues la temperatura influye en su distribución y abundancia.

  2. Change in the biotype composition of Bemisia tabaci in Shandong Province of China from 2005 to 2008.

    Science.gov (United States)

    Chu, Dong; Wan, Fang Hao; Zhang, You Jun; Brown, Judith K

    2010-06-01

    Certain biotypes of the Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) complex cause extensive damage and are important pests and virus vectors in agricultural crops throughout the world. Among the most invasive and well studied are the B and Q biotypes. Recent reports in Shandong Province, China, have indicated that the Q biotype was introduced there in approximately 2005, whereas the B biotype has been established there for approximately 10 yr. Even so, the present distribution of the two biotypes in Shandong has not been examined. The results of this study showed that the B and Q biotypes are both present in Shandong Province based on bar-coding using a approximately 450-base fragment of the mitochondrial cytochrome oxidase I (mtCOI) gene. In addition, a B biotype-specific polymerase chain reaction primer pair that amplifies a approximately 300 bp mtCOI fragment was designed and used to examine the biotype composition of B. tabaci in selected crops from six provincial locations, using the general mtCOI primers as an internal positive control for DNA quality. The results of this study indicated that the Q biotype was the predominant B. tabaci colonizing all of the crops in the study sites examined. This suggests that the Q biotype has displaced the B biotype in Shandong Province of China, which until now was the predominant biotype. This is the first report of the displacement of the B by the Q biotype in field grown crops in China, and in a locale where neither the B nor the Q biotype is native. We hypothesize that this phenomenon may have been exacerbated by the widespread use of neonicotinoid insecticides for whitefly control, given the sustained efficacy thus far of neonicotinoids against the B biotype, and their failure at times to effectively control the Q biotype.

  3. Acyrthosiphon pisum (Harris) (Homoptera: Aphididae) infestation ...

    African Journals Online (AJOL)

    Once a minor pest, the pea aphid, Acyrthosiphon pisum has already become a major pest of grass pea (Lathyrus sativus), in Ethiopia, particularly in the northwestern region. The effect of two levels of chemical treatment on pea aphids and their natural enemies was investigated in a field experiment in Achefer, northwestern ...

  4. Surtos populacionais de Bemisia tabaci no estado de São Paulo Outbreaks of Bemisia tabaci in the São Paulo State, Brazil

    OpenAIRE

    André Luiz Lourenção; Hiroshi Nagai

    1994-01-01

    A partir de 1991, tem sido observada a presença da mosca-branca Bemisia tabaci (Genn.) (Homoptera: Aleyrodidae) em altas populações em hortaliças e orna-mentais nos municípios paulistas de Paulínia, Holambra, Jaguariúna e Artur Nogueira. Foram constatadas infestações severas em tomateiro, brócolos, berinjela e aboboreira; nesta última, o sintoma observado em plantas infestadas pela mosca-branca é o prateamento da face superior das folhas, em conjunto com queda drástica da produção. Uma lavour...

  5. Aspects of the ecology of spittlebugs (Homoptera: Cercopidae) in ...

    African Journals Online (AJOL)

    Species type and pattern of distribution of spittlebugs was studied from 6th March to 15th December 2009 within the University of Nigeria, Nsukka campus. Three spittlebug species namely, Deois flavopicta, Aphrophora saratogensis and Philaenus spumarius were identified within the University campus. Whereas A.

  6. Distributional patterns and possible origin of leafhoppers (Homoptera, Cicadellidae

    Directory of Open Access Journals (Sweden)

    Mervin W. Nielson

    2000-03-01

    Full Text Available The zoogeographical distribution of 42 cicadellid subfamilies and their assigned tribes and genera is compiled with distributional maps and proposed dispersal pathways of genera that are shared interzoogeographically. Possible origin of the subfamilies and tribes is proposed in an ancestral context from which the more modern extant groups evolved whereas origin of genera is in a more modern context. Notwithstanding their complex biogeography, the distributional data of the higher groups indicate that all of the cosmopolitan and near cosmopolitan subfamilies arose during early Cretaceous or possibly the late Jurassic period (140-116 m.y.a. when continental drift was in its early stages. Nearly all of the New World and some Old World subfamilies are considered of more recent origin (late Cretaceous-Tertiary. Ninety percent of the known genera (2,126 are endemic to their respective zoogeographical region and subregion, thus indicating relatively high host specificity and low rate of dispersal. The majority (76% of known extant genera are pantropical in origin, suggesting early or possible Gondwanaland origin of their ancestors. Dispersal pathways of genera shared by more than one zoogeographical region were generally south to north (Neotropical/Nearctic, Oriental/Palaearctic or west to east (Palaearctic/Nearctic, Oriental/Australian, from regions of high diversity to regions of low diversity and from warmer climates to cooler climates. The most diverse and richest leafhopper fauna are present in the Neotropical and Ethiopian regions although taxal affinities between them are poorest. The most depauperate fauna are in the Nearctic region and in Australia, reflecting the impact of isolating and ecological factors on distribution and radiation. Ecological barriers were more evident between the Ethiopian and Oriental fauna than between any other zoogeographical combination. Taxal affinities appeared to be correlated with close continental proximities. Vicariance (physical was the principal event that appealed to explain the distribution of many subfamilies and tribes whereas dispersal accounted for distribution of the majority of interzoogeographical genera.

  7. Aphids of Java. Part V: Aphidini (Homoptera: Aphididae)

    NARCIS (Netherlands)

    Noordam, D.

    2004-01-01

    Examined material, host plants and etymology are given of 22 species, all viviparous and belonging to the genera Aphis, Brachysiphoniella, Hyalopterus, Hysteroneura, Melanaphis, Rhopalosiphum, Schizaphis and Toxoptera. Keys to the included species are given.

  8. Calling songs of some South African cicadas (Homoptera: Cicadidae)

    African Journals Online (AJOL)

    1987-07-13

    Jul 13, 1987 ... The spectral and temporal characters of the calls of 12 species of cicada are illustrated and described. Variation within populations of conspecifics appears to be greater in temporal than in spectral properties. Conspecific calls recorded at widely separated localities have essentially the sarne characteristics.

  9. Una nueva especie de Iragua Melichar, 1926 (Insecta: Homoptera: Cicadellidae

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    Pedro W. Lozada

    2014-06-01

    Full Text Available Se describe e ilustra una nueva especie de Iragua Melichar, I. chola sp. n., de material procedente de la Zona Reservada de Tambopata, departamento de Madre de Dios, y de Chanchamayo, departamento de Junín, en Perú. El material tipo se encuentra depositado en las colecciones del Museo Nacional de Historia Natural y del Museo de Entomología de la Universidad Nacional Agraria La Molina, Lima, Perú.

  10. The male of Nancyana curva (Homoptera: Cicadellidae from southeastern Brazil

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    Luci Boa Nova Coelho

    1999-12-01

    Full Text Available The adult male of Nancyana curva is described and illustrated for the first time, based on four specimens from the states of Rio de Janeiro and Minas Gerais. Male diagnostic characters include the presence of a pair of inner projections on the dorsal lobe of the pygofer, and a dorsal pair of short subapical processes on the aedeagus. The female color pattern is similar to that of male, with dark brown bands on torax not so clear.

  11. A synopsis of the tribe Micrutalini Haupt (Homoptera, Membracidae, Smiliinae

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    Albino M. Sakakibara

    1999-01-01

    Full Text Available The tribe Micrutalini and its two genera, Trachytalis Fowler and Micrutalis Fowler, are redescribed. The following species are treated and, in some cases, nomenclatura! changes introduced: Trachytalis isabellina Fowler, 1895; T. distinguenda Fowler, 1895; T. retrofasciata (Lethierry, 1890, comb.n.; Micrutalis alrovena Goding, 1930; M. balteata (Fairmaire, 1846 = Aculalis lucidus Buckton, 1902, syn.n.; M. bella Goding, 1929; M. biguttula (Fairmaire, 1846, comb.n.; M. binaria (Fairmaire, 1846 = Acutalis flavivenlris Lethierry, 1890, syn.n.; M. callan-gensis Goding, 1930; M. calva (Say, 1830; M. discalis (Walker, 1858; M. dorsalis (Fitch, 1851; M. dubia Fowler, 1895 = M. zeteki Goding, 1928, syn.n.; M. flava Goding, 1929; M. flavozonala (Fairmaire, 1846, comb.n. = Acutalis geniculata Stál, 1862, syn.n. = Acutalis modesta Stál, 1862, syn.n.; M. godfreyi Sakakibara, 1976; M. incerla Sakakibara, 1976; M. lata Goding, 1930; M. litlerala (Fairmaire, 1846, comb.n.;M lugubrina(Stál, 1862;M malleiferaFovj]er, 1895 = M binariamutabilis Fowler, 1895, syn.n.; M. minutus Buckton, 1902; M. nigrolineata (Stál, 1864; M. nigromarginata Funkhouser, 1940; M. notalipennis Fowler, 1895; M. occidentalis (Goding, 1893; M. pollens Fowler, 1895; M. parva (Goding, 1893; M. plagíala (Stál, l&62 = AcutalisvariabiIisBerg, 1879,syn.n. =M. chapadensisGoding, 1930,syn.n.; M. punctifera (Walker, 1858; M. semialba (Stál, 1862; M. stipulipennis Buckton, 1902; M. tau Goding, 1930; M. trifurcala Goding, 1893; M. tripunctata (Fairmaire, 1846 = Acutalis moesta Stál, 1859, syn.n. = M. tartaredoides Goding, 1930, syn.n.. New species: Micrutalis diminuta sp.n. (Ecuador, Pichincha; Micrutalis divisa sp.n. (Brazil, Mato Grosso; Micrutalis henki sp.n. (Panama, Canal Zone; Micrutalis infúscala sp.n. (Venezuela, Portuguesa; Micrutalis margínala sp.n. (Brazil, Mato Grosso; Micrutalis meridana sp.n. (Venezuela, Mérida; Micrutalis mucuya sp.n. (Venezuela, Mérida; Micrutalis robustula sp.n. (Venezuela, Caracas; M. seminigra sp.n. (Brazil, Paraná; Micrutalis turriba sp.n. (Costa Rica, Turrialba. Lectotypes are designated for: Acutalis balteata Fairmaire, 1846, Aculalis binaria Fairmaire, 1846, Acutalis flavozonala Fairmaire, 1846, una Acutalis tripunctata Fairmaire, 1846. New taxonomic position: Micrutalis melanogramma (Petty, 1833 is transferred to Melu-sinella Metcalf, 1952 (Ceresini - Melusinella melanogramma (Petty, 1833, comb.n. = Melusinella nervosa (Fairmaire, 1846, syn.n.. Species incertae sedis: Tragopa ephippium Burmeister, 1836.

  12. Cytogenetics of two species of Euceraphis (Homoptera, Aphididae).

    Science.gov (United States)

    Blackman, R L

    1976-07-30

    Somatic cell divisions, spermatogenesis, and the prophase stages of primary oocytes, are described for two species of birch aphid, Euceraphis betulae (Koch) and E. punctipennis (Zettersted). Females of E. betulae have two autosome pairs, two pairs of X-chromosomes of different lengths, and two B-chromosomes. Females of E. punctipennis have the same number of X-chromosomes. The sex determination system is X1X2O. E. punctipennis males sometimes have only one B-chromosome. In the spermatogenesis of E. Betulae, pairing of homologous autosomes occurs in early prophase I, but no evidence was found of chiasmata or end-to-end alignment of homologues. Instead, homologues remain closely aligned in parallel as they condense into metaphase, and anaphase I separates the products of pairing in a strictly reductional manner. The two unpaired X-chromosomes and both B-chromosomes are stretched on the anaphase I spindle and all four pass into the larger secondary spermatocyte. The second division is equational. The B-chromosomes thus show accumulation in spermatogenesis, which must be compensated in some way by an elimination mechanism in oogenesis. Meiosis of E. punctipennis is highly anomalous. The two autosomes pair but separate again in early prophase I, then one homologue becomes heterchromatic and is apparently rejected from the late prophase nucleus. A single, equational maturation division follows. In female neiosis I, both species show highly characteristic diplotene figures with multiple chiasmata, the B-chromosomes remaining unpaired. These results are discussed in relation to previous work on aphid cytogenetics.

  13. Range Expansion of Metcalfa pruinosa (Homoptera: Fulgoroidea in Southeastern Europe

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    Cristina Preda

    2011-07-01

    Full Text Available The citrus flatid planthopper Metcalfa pruinosa, a Nearctic species of Fulgoroidea: Flatidae, was accidentally introduced in Europe, first in Italy in the late 1970’s. In a few decades, Metcalfa pruinosa has spread over most of Europe, finally reaching the Black Sea coast in 2009. Hundreds of individuals of different life stages were observed for the first time in the southeastern part of Romania throughout the summer of 2009 on several host plants: Hibiscus syriacus, Ligustrum vulgare, Robinia pseudoacacia, Evonymus japonicus, Spirea x vanhouttei, Aesculus hippocastanum, Philadelphus coronarius, Ficus carica, Vitis vinifera, Fraxinus pennsylvanica. The number of individuals observed and the area covered increased dramatically in 2010 as well as the number of host plants (110 species in 49 families, suggesting the planthopper is in the expansion phase of the invasion process.

  14. Influence Of Phytolyma lata (Homoptera: Psyllidae) On Seedling ...

    African Journals Online (AJOL)

    There were no significant differences (P > 0.05) in yield, specific leaf area, leaf area ratio and leaf weight ratio of plants growing in the open screen house and open plot without screening (infested plots) even though irradiance incident in the open screen house was 70% of that in the open plot without screening.

  15. Appearance of Neotoxoptera formosana (Homoptera: Aphididae) in The Netherlands

    NARCIS (Netherlands)

    Piron, P.G.M.

    2010-01-01

    Neotoxoptera formosana (Takahashi) is a pest of wild and cultivated Allium species, but never iwht disastrous consequences. In 1984, N. formosana was found in France. This was the first finding in Europe. Since then, N. formosana has been observed also in other European countries. The first record

  16. Calling songs of some South African cicadas (Homoptera: Cicadidae)

    African Journals Online (AJOL)

    1987-07-13

    Jul 13, 1987 ... frequency band width and emphasized frequency of the call were measured from the power spectra. Pulse rates were measured from wide band (300 Hz ... pulses. Narrow band sonagrams show a slight frequency modulation at a rate of 115 modulations/s, corresponding to groups of four double pulses in ...

  17. Biology of Diaphorina citri (Homoptera: Psyllidae) on four host plants.

    Science.gov (United States)

    Tsai, J H; Liu, Y H

    2000-12-01

    The biology of the citrus psyllid Diaphorina citri Kuwayama was studied at 25 degrees C on four commonly grown citrus and related plants [rough lemon, Citrus jambhiri Lush; sour orange, C aurantium L.; grapefruit, C. paradisi Macfadyen; and orange jessamine, Murraya paniculata (L.) Jack] in the laboratory. The biological characteristics of each life stage are described. The average egg incubation periods on orange jessamine, grapefruit, rough lemon, and sour orange varied very little (4.1-4.2 d). The average nymphal developmental periods on these four host plants were essentially the same except the fifth stadium. Survival of immatures on orange jessamine, grapefruit, rough lemon, and sour orange was 75.4, 84.6, 78.3, and 68.6%, respectively. Female adults lived an average of 39.7, 39.7, 47.6, and 43.7 d on these respective host plants. The average number of eggs laid per female on grapefruit (858 eggs) was significantly more than those on other hosts (P citri on grapefruit was highest. Jackknife estimates of r(m) varied from 0.188 on grapefruit to 0.162 on orange jessamine and rough lemon. The mean population generation time on these hosts ranged from 31.6 to 34.1 d. The continuous flushes produced by orange jessamine could play an important role in maintaining high populations of this vector when the new flushes are not available in the commercial citrus groves.

  18. Biosystematic studies on the Muellerianella complex (Delphacidae Homoptera Auchenorrhyncha)

    NARCIS (Netherlands)

    Drosopoulos, S.

    1977-01-01

    The genus Muellerianella comprises the species: M. farmairei, M. brevipennis, M. relicta and one pseudogamous all-female biotype M. fairmairei (3n). The bisexual species M. fairmairei and M.

  19. Perkembangan Populasi Empoasca sp. (Homoptera : Cicadelidae di Kebun Teh Pagilaran

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    Pachrudin Pachrudin

    2007-07-01

    Full Text Available Empoasca sp. was first reported as pest in West Java tea plantation in 1998. In 2000, this cicadellid was also found in Pagilaran tea plantation in Central Java. The aim of this research was to observe the preferences of Empoasca sp. to tea cultivars and the effect of altitude and climate factors to population dynamics of Empoasca sp. the result showed that Kiara 8 cultivar planted in 700 - 850 m asl was highly susceptible to Empoasca sp. The lowest population and the least damage was found in PS 1 cultivar which has leaves with the densest hair. Intensity of the rain-fall was likely to have higher impact to population of Empoasca sp. rather than humidity and temperature.

  20. (Neuroptera: Chrysopidae fed with Aleurocanthus woglumi (Hemiptera: Aleyrodidae

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    Robério de Oliveira

    2016-02-01

    Full Text Available This study evaluated the development and reproduction of Ceraeochrysa cubana when fed the citrus blackfly Aleurocanthus woglumi. The study was carried out at the Laboratory of Entomology, Department of Plant and Environmental Sciences, Federal University of Paraíba – Areia/PB. It used a completely randomized design. The study was conducted in climate chambers, regulated to 26 ± 2°C and a relative humidity of 70 ± 10% with a 12 h photoperiod. The treatments were as follows: eggs, nymphs of only the 1st, 2nd, 3rd, or 4th instars, and nymphs of multiple instars (1st, 2nd, 3rd, and 4th instars of A. woglumi, with eggs of Sitotroga cerealella as a control. The 1st instar of C. cubana lasted 5.8 to 10.7 days, the 2nd instar lasted 6.0 to 13.3 days, and the 3rd instar lasted 8.2 to 18.5 days. The larvae of C. cubana did not survive when the food provided was only the eggs of A. woglumi, since the predator could not eat them. C. cubana, when provided nymphs of multiple instars (1st, 2nd, 3rd, and 4th instars of the citrus blackfly, had a shorter pre-pupal period and lower longevity than when consuming the eggs of S. cerealella, but the sex ratio and oviposition period were not affected. However, changes occurred in the pre-oviposition period, the total number of eggs, and the number of viable eggs.

  1. Assesing Bemisia tabaci (Genn. biotype B resistance in soybean genotypes: Antixenosis and antibiosis Evaluación de la resistencia de genotipos de soya a Bemisia tabaci (Genn. biotipo B: Antixenosis y antibiosis

    Directory of Open Access Journals (Sweden)

    José Paulo Gonçalves Franco da Silva

    2012-12-01

    Full Text Available Since it was first reported in Brazil in the 1990s, the B biotype of silverleaf whitefly (Bemisia tabaci Genn., Hemiptera: Aleyrodidae has been recognized as an important pest in soybeans (Glycine max L., reducing the productivity of this legume species in some areas of the country. As an alternative to chemical control, the use of resistant genotypes represents an important tool for integrated pest management (IPM. This study evaluated the performance of 10 soybean genotypes prior to whitefly infestation, by testing attractiveness and preference for oviposition in the greenhouse and antibiosis in the laboratory. In a multiple-choice test, 'IAC-17' was the least attractive to insects. In a no-choice test, 'IAC-17' was the least attractive for egg deposition, indicating the occurrence of non-preference for oviposition on this genotype. Trichome density was positively correlated with the oviposition site and may be associated with the resistance of 'IAC-17' to infestation. The genotypes 'IAC-PL1', 'IAC-19', 'Conquista', 'IAC-24' and 'IAC-17' extended the insect's life cycle, indicating the occurrence of a small degree of antibiosis and/or non-preference for feeding.Desde que se registró por primera vez en Brasil en la década de 1990, el biotipo B de la mosca-blanca (Bemisia tabaci Genn., Hemiptera: Aleyrodidae, se reconoce como una importante plaga de la soya (Glycine max L. y es lo que reduce la productividad de estas especies de leguminosas en algunas zonas del pais. Como una alternativa al control químico, el uso de genotipos resistentes representa una herramienta importante para la gestión integrada de plagas (MIP. Este trabajo evaluó el comportamiento de 10 genotipos de soya frente al ataque de la mosca-blanca, por medio de ensayos de atractividad y preferencia para ovipostura en invernaderos y antibiosis en laboratorio. En una prueba de elección multiple, 'IAC-17' fue el menos atractivo para los insectos. En una prueba sin elecci

  2. Resistência de genótipos de feijoeiro a Bemisia tabaci biótipo B Resistance of bean genotypes to Bemisia tabaci biotype B

    Directory of Open Access Journals (Sweden)

    Lucas Castro Torres

    2012-01-01

    Full Text Available O estudo de genótipos de feijoeiro resistentes à mosca-branca Bemisia tabaci (Genn. biótipo B (Hemiptera: Aleyrodidae é de grande importância devido aos danos ocasionados por essa praga à cultura. Neste trabalho, foram estudados a atratividade para adultos, a preferência para oviposição em testes com e sem chance de escolha, o ciclo ovo-adulto e o tipo e número de tricomas presentes nos folíolos. Os experimentos foram realizados em casa de vegetação avaliando-se, inicialmente, cem genótipos de feijoeiro. A resistência do tipo não-preferência para alimentação e/ou antibiose foi observada nos genótipos ARC-3, IAC-Alvorada e Canário 101, sendo a emergência de adultos fortemente influenciada pelos genótipos. Também se observou correlação negativa moderada entre o número de ovos e o número de tricomas glandulares, e correlação positiva muito forte entre o número de ovos e o número de tricomas tectores unciformes.The study of bean genotypes resistant to the whitefly Bemisia tabaci (Genn. B biotype (Hemiptera: Aleyrodidae has been of great importance due to the damage caused by this pest. In this research, bean genotypes were evaluated regarding attractiveness to whitefly adults, the preference for oviposition in free-choice and non choice tests, egg-to-adult development time and characterized for the presence, type and number of trichomes. The experiments were carried out under greenhouse conditions initially evaluating 100 bean genotypes. The non-preference type of resistance for feeding and/or antibiosis was observed in the genotypes ARC-3, IAC-Alvorada and Canário 101, and the emergence of adults was strongly influenced by the genotypes. It was also observed a moderate negative correlation between the number of eggs and the number of glandular trichomes, as well as a very strong positive correlation between the number of eggs and the number of unciform non-glandular trichomes.

  3. On the taxonomy of Anaceratagallia Zachvatkin, 1946 (Homoptera: Auchenorrhyncha: Cicadellidae: Agalliinae) of Western Kyrgyzstan.

    Science.gov (United States)

    Tishechkin, Dmitri Yu

    2017-06-01

    In Western Kyrgyzstan the genus Anaceratagallia includes four species: A. venosa (de Fourcroy, 1785), A. aciculata (Horvath, 1894), A. laevis (Ribaut, 1935) = A. acuteangulata Dubovskiy, 1966 nec Zachvatkin, 1946, and A. alabugensis Dubovskiy, 1966 = A. collicola Dubovskiy, 1966, syn. n. = A. turanica Dubovskiy, 1966, syn. n. = A. laevis Dubovskiy, 1966 nec Ribaut, 1935. Illustrated descriptions and male calling signal oscillograms for all species are given. The range of A. acuteangulata Zachvatkin, 1946 includes Italy, Greece, Turkey, and North Caucasus; records of this species from Ukraine, Kazakhstan and Central Asia are erroneous. Investigation of morphological and acoustic characters in Anaceratagallia showed that small differences in the shape of male genitalia and 2nd abdominal apodemes are not species-specific traits.

  4. The tribe Acutalini Fowler (Homoptera, Membracidae, Smiliinae: new genera, new species and some nomenclatural changes

    Directory of Open Access Journals (Sweden)

    Albino M Sakakibara

    1997-09-01

    Full Text Available The tribe Acutalini Fowler is redescribed as well as the genera Acutalis Fairmaire, Euritea Stål, and Thrasymedes Kirkaldy. The following new taxa and nomenclatural changes are presented: Thrasymedes mexicana sp.n. (from Mexico, Oaxaca; Bordonia gen.n., with B. venezuelana sp.n. (type-species (from Venezuela, Portachuelo, B. clypeata sp.n. (from Colombia, Cuesta Boba, B. majuscula sp.n. (from Venezuela, Portachuelo, and Cornutalis gen.n., with C. cauca sp.n. (type-species (from Colombia, Cauca, and C. validu sp.n. (from Ecuador, Sto. Domingo. Acutalis fusconervosa Fairmaire, 1846 = Horiola venosa Walker, 1858, syn.n.; Euritea munda (Walker, 1858 = Stictolobus nitidus Funkhouser, 1940, syn.n.; Bordonia nigricosta (Goding, 1926, comb.n.; Bordonia virescens (Funkhouser, 1940, comb.n.. One species is transferred to Smiliinae-Ceresini: Tapinolobus curvispina (Walker, 1858, comb.n. (formerly in Thrasymedes = Tapinolobus fasciatus Sakakibara, 1969, syn.n.; another one is transferred to Darninae-Cymbomorphini: Eumela darnioides (Walker, 1858, comb.n. (formerly in Euritea.

  5. Sex attractant pheromone of damson-hop aphid Phorodon humuli (Homoptera, aphididae).

    Science.gov (United States)

    Campbell, C A; Dawson, G W; Griffiths, D C; Pettersson, J; Pickett, J A; Wadhams, L J; Woodcock, C M

    1990-12-01

    Behavioral studies using an olfactometer demonstrated that sexual females (oviparae) of the damson-hop aphid,Phorodon humuli, release a pheromone to which males respond. Volatiles produced by the oviparae were analyzed by coupled gas chromatography-single cell recording from the secondary rhinaria on the male antenna and showed the presence of one peak with major activity. Coupled gas chrornatography-mass spectrometry suggested a nepetalactol, which was shown to have the 4aR, 7S, 7aS stereochemistry by synthesis from the corresponding nepetalactone isolated from the labiate plantNepeta mussinii. Although the stereochemistry at carbon-1 is not yet established, a synthetic sample comprising ca. 70% 1S and 30% 1R attracted highly significant numbers of males to water traps placed within and adjacent to a hop garden. Initial studies also indicated attraction of males in both the olfactometer and in the field by volatiles from the primary host.

  6. Collective defense of Aphis nerii and Uroleucon hypochoeridis (Homoptera, Aphididae against natural enemies.

    Directory of Open Access Journals (Sweden)

    Manfred Hartbauer

    2010-04-01

    Full Text Available The prevalent way aphids accomplish colony defense against natural enemies is a mutualistic relationship with ants or the occurrence of a specialised soldier caste typical for eusocial aphids, or even both. Despite a group-living life style of those aphid species lacking these defense lines, communal defense against natural predators has not yet been observed there. Individuals of Aphis nerii (Oleander aphid and Uroleucon hypochoeridis, an aphid species feeding on Hypochoeris radicata (hairy cat's ear, show a behavioral response to visual stimulation in the form of spinning or twitching, which is often accompanied by coordinated kicks executed with hind legs. Interestingly, this behaviour is highly synchronized among members of a colony and repetitive visual stimulation caused strong habituation. Observations of natural aphid colonies revealed that a collective twitching and kicking response (CTKR was frequently evoked during oviposition attempts of the parasitoid wasp Aphidius colemani and during attacks of aphidophagous larvae. CTKR effectively interrupted oviposition attempts of this parasitoid wasp and even repelled this parasitoid from colonies after evoking consecutive CTKRs. In contrast, solitary feeding A. nerii individuals were not able to successfully repel this parasitoid wasp. In addition, CTKR was also evoked through gentle substrate vibrations. Laser vibrometry of the substrate revealed twitching-associated vibrations that form a train of sharp acceleration peaks in the course of a CTKR. This suggests that visual signals in combination with twitching-related substrate vibrations may play an important role in synchronising defense among members of a colony. In both aphid species collective defense in encounters with different natural enemies was executed in a stereotypical way and was similar to CTKR evoked through visual stimulation. This cooperative defense behavior provides an example of a surprising sociality that can be found in some aphid species that are not expected to be social at all.

  7. Mechanisms of Oryza sativa (Poaceae) resistance to Tagosodes orizicolus (Homoptera: Delphacidae) under greenhouse condition in Venezuela

    National Research Council Canada - National Science Library

    González, Alex; Labrín, Natalia; Alvarez, Rosa M; Jayaro, Yorman; Gamboa, Carlos; Reyes, Edicta; Barrientos, Venancio

    2012-01-01

    ... of the "Rice hoja blanca virus". During 2006-2007 we carried out research under greenhouse conditions at Fundaci6n Danac, Venezuela, in order to determine the mechanisms of antixenosis, antibiosis and tolerance...

  8. Mechanisms of Oryza sativa (Poaceae) resistance to Tagosodes orizicolus (Homoptera: Delphacidae) under greenhouse condition in Venezuela

    OpenAIRE

    González, Alex; Labrín, Natalia; Álvarez, Rosa M.; Jayaro, Yorman; Gamboa, Carlos; Reyes, Edicta; Barrientos,Venancio

    2012-01-01

    Tagosodes orizicolus is one of the main plagues of rice in tropical America causing two types of damages, the direct one, feeding and oviposition effect, and an indirect one, by the transmission of the “Rice hoja blanca virus”. During 2006-2007 we carried out research under greenhouse conditions at Fundación Danac, Venezuela, in order to determine the mechanisms of antixenosis, antibiosis and tolerance to T. orizicolus, which could be acting in commercial varieties and advanced lines of the r...

  9. Mechanisms of Oryza sativa (Poaceae) resistance to Tagosodes orizicolus (Homoptera: Delphacidae) under greenhouse condition in Venezuela

    OpenAIRE

    Alex González; Natalia Labrín; Álvarez, Rosa M.; Yorman Jayaro; Carlos Gamboa; Edicta Reyes; Venancio Barrientos

    2012-01-01

    Tagosodes orizicolus is one of the main plagues of rice in tropical America causing two types of damages, the direct one, feeding and oviposition effect, and an indirect one, by the transmission of the “Rice hoja blanca virus”. During 2006-2007 we carried out research under greenhouse conditions at Fundación Danac, Venezuela, in order to determine the mechanisms of antixenosis, antibiosis and tolerance to T. orizicolus, which could be acting in commercial varieties and advanced li...

  10. Relationships Between Aphids (Insecta: Homoptera: Aphididae) and Slugs (Gastropoda: Stylommatophora: Agriolimacidae) Pests of Legumes (Fabaceae: Lupinus).

    Science.gov (United States)

    Kozłowski, Jan; Strażyński, Przemysław; Jaskulska, Monika; Kozłowska, Maria

    2016-01-01

    Lupin plants are frequently damaged by various herbivorous invertebrates. Significant among these are slugs and aphids, which sometimes attack the same plants. Relationships between aphids, slugs and food plant are very interesting. Grazing by these pests on young plants can lead to significant yield losses. There is evidence that the alkaloids present in some lupin plants may reduce grazing by slugs, aphids and other invertebrates. In laboratory study was analyzed the relationships between aphid Aphis craccivora and slug Deroceras reticulatum pests of legumes Lupinus angustifolius. It was found that the presence of aphids significantly reduced slug grazing on the plants. The lupin cultivars with high alkaloid content were found to be less heavily damaged by D. reticulatum, and the development of A. craccivora was found to be inhibited on such plants. © The Author 2016. Published by Oxford University Press on behalf of the Entomological Society of America.

  11. Resolving relationships over a wide taxonomic range in Delphacidae (Homoptera) using the COI gene

    NARCIS (Netherlands)

    Dijkstra, E.G.M.; Rubio, J.M.; Post, R.J.

    2003-01-01

    Using a combination of different methods to investigate the suitability of a fragment of the cytochrome c oxidase I gene (COI), we succeeded in partially resolving phylogenetic relationships in Delphacidae from the level of species to subfamily. Spectral analysis applied to the relatively noisy COI

  12. A selected bibliography of the Coccoidea (Homoptera), third supplement (1970-1985)

    OpenAIRE

    Kosztarab, Michael, 1927-; Kosztarab, Matilda P.

    1988-01-01

    compiled by Michael Kosztarab and Matilda P. Kosztarab Part of a 16-volume set. Volumes 1-11 were published in the Research Division bulletin (Virginia Polytechnic Institute and State University. Research Division).

  13. Mechanisms of Oryza sativa (Poaceae resistance to Tagosodes orizicolus (Homoptera: Delphacidae under greenhouse condition in Venezuela

    Directory of Open Access Journals (Sweden)

    Alex González

    2012-03-01

    Full Text Available Tagosodes orizicolus is one of the main plagues of rice in tropical America causing two types of damages, the direct one, feeding and oviposition effect, and an indirect one, by the transmission of the “Rice hoja blanca virus”. During 2006-2007 we carried out research under greenhouse conditions at Fundación Danac, Venezuela, in order to determine the mechanisms of antixenosis, antibiosis and tolerance to T. orizicolus, which could be acting in commercial varieties and advanced lines of the rice genetic breeding programs of INIA and Fundación Danac. The method of free feeding was used for the antixenosis evaluation, whereas the method of forced feeding was used for antibiosis evaluation (effect on survival and oviposition. Additionally, we used the indirect method based on biomass depression to estimate the tolerance. Some of the evaluated traits included: grade of damage, number of insects settling on rice plants, percentage of sogata mortality at the mature state, number of eggs in the leaf midrib and an index of tolerance. The results showed that rice genotypes possess different combinations of resistance mechanisms, as well as different grades of reactions. The susceptible control ‘Bluebonnet 50’ was consistently susceptible across experiments and the resistant control ‘Makalioka’ had high antixenosis and high antibiosis based on survival and oviposition. The rest of the genotypes presented lower or higher degrees of antixenosis and antibiosis for survival and viposition. The genotype ‘FD0241-M-17-6-1-1-1-1’ was identified with possible tolerance to the direct damage of sogata.

  14. Comparative biology of three Scymnus lady beetles (Coleoptera: Coccinellidae): predators of Adelges tsugae (Homoptera: Adelgidae)

    Science.gov (United States)

    Wenhua Lu; Michael E. Montgomery

    2000-01-01

    Scymnus (Neopullus) sinuanodulus Yu et Yao, S. (N.) camptodromusYu et Liu, and Scymnus (Neopullus) n. sp. (in press) were collected in the People's Republic of China from hemlocks infested with the hemlock woolly adelgid, Adelges tsugae Annand. To date, 3 of the 14 provinces in China where...

  15. Biology of Scymnus ningshanensis (Coleoptera: Coccinellidae): A predator of Adelges tsugae (Homoptera: Adelgidae)

    Science.gov (United States)

    Michael Montgomery; Hongbin Wang; Defu Yao; Wenhau Lu; Nathan Havill; Guangwu. Li

    2002-01-01

    Information is presented on the occurrence, development, and feeding of Scymnus (Neopullus) ningshanensis Yu et Yao. Information on its biology was collected in the field and laboratory in China and in quarantine in the United States. This lady beetle was found in China only on hemlock infested with ...

  16. Eine neue Art der Gattung Fieberiella Signoret, 1880 (Insecta, Homoptera) aus Griechenland

    NARCIS (Netherlands)

    Wagner, Wilhelm

    1963-01-01

    Vom Herrn W. H. Gravestein, Amsterdam, erhielt ich eine Anzahl Zikaden zur Bestimmung, die während einer Entomologischen Exkursion des Zoologischen Museums Amsterdam in Griechenland gesammelt worden sind. Darunter befand sich auch eine neue Fieberiella-Art. Eine taxionomische Bearbeitung der drei

  17. Aploneura lentisci (Homoptera: Aphididae and its interactions with fungal endophytes in perennial ryegrass (Lolium perenne

    Directory of Open Access Journals (Sweden)

    Alison Jean Popay

    2016-09-01

    Full Text Available Aploneura lentisci Pass. is endemic to the Mediterranean region where it is holocyclic, forming galls on its primary host, Pistacia lentiscus and alternating over a 2 year period between Pistacia and secondary hosts, principally species of Graminae. This aphid is widely distributed in Australia and New Zealand on the roots of the common forage grasses, ryegrass (Lolium spp. and tall fescue (Schedonorus phoenix where it exists as permanent, anholocyclic, parthenogenetic populations. Previous studies have indicated that infestations of A. lentisci significantly reduce plant growth and may account for differences in field performance of Lolium perenne infected with different strains of the fungal endophyte Epichloë festucae var lolii. These obligate biotrophs protect their host grasses from herbivory via the production of alkaloids. To confirm the hypothesis that growth of L. perenne is associated with the effect of different endophyte strains on aphid populations, herbage and root growth were measured over time in two pot trials that compared three fungal endophyte strains with an endophyte-free control. In both pot trials, aphid numbers were lowest on plants infected with endophyte strain AR37 at all sampling times. In plants infected with a common toxic strain naturalized in New Zealand, aphid numbers overall were lower than on uninfected plants or those infected with strain AR1, but numbers did not always differ significantly from these treatments. Populations on AR1-infected plants were occasionally significantly higher than those on endophyte-free. Cumulative foliar growth was reduced in AR1 and Nil treatments relative to AR37 in association with population differences of A. lentisci in both trials and root dry weight was reduced in one trial. In four Petri dish experiments survival of A. lentisci on plants infected with AR37 declined to low levels after an initial phase of up to 19 days during which time aphids fed and populations were similar to those on plants without endophyte. Aphids on AR37-infected plants became uncoordinated in their movement and developed tremors before dying suggesting a neurotoxin was responsible for their mortality. Results support the hypothesis that differences in A. lentisci populations due to to endophyte infection status and strain affects plant growth.

  18. Microsatellite marker analysis of peach-potato aphids (Myzus persicae, Homoptera: Aphididae) from Scottish suction traps.

    Science.gov (United States)

    Malloch, G; Highet, F; Kasprowicz, L; Pickup, J; Neilson, R; Fenton, B

    2006-12-01

    The peach-potato aphid Myzus persicae (Sulzer) is an important vector of plant viruses. A network of suction traps collects aerial samples of this aphid in order to monitor and help predict its spatial distribution and likely impact on virus transmission in crops. A suction trap catch is thought to be a good representation of the total aphid pool. Sensitive molecular markers have been developed that determine the genetic composition of the M. persicae population. In Scotland, UK, these were applied to field collections revealing a limited number of clones. Molecular markers are less successful when applied to specimens that have been preserved in an ethanol-based trap fluid designed to preserve morphology. An assessment of different DNA extraction and PCR techniques is presented and the most efficient are used to analyse M. persicae specimens caught in the Dundee suction trap in 2001, a year when exceptionally high numbers were caught. The results reveal that the majority of the M. persicae caught belonged to two highly insecticide resistant clones. In addition, it was possible to compare the relative frequencies of genotypes caught in the trap with those collected at insecticide treated and untreated field sites in the vicinity. These results indicate that, in addition to suction trap data, the ability to sample field sites provides valuable early warning data which have implications for pest control and virus management strategies.

  19. TOKSISITAS BEBERAPA HASIL EKSTRAK DAUN TEMBAKAU TERHADAP Myzus persicae (Homoptera;Aphididae

    Directory of Open Access Journals (Sweden)

    - Sudjak

    2015-09-01

    Full Text Available Penggunaan pestisida kimia sintetik yang tidak rasional dapat menyebabkan pencemaran air, tanah, udara, produk pertanian, keracunan manusia/pekerja, resistensi/resurgensi hama, terbunuhnya hewan bermanfaat, perubahan status hama, dan ledakan hama. Untuk itu dirasa perlu mencari pestisida alternatif untuk mendukung pertanian yang berkelanjutan . Melalui kegiatan penelitian yang bertahap telah diperoleh produk pestisida yang diesktrak dari sisa-sisa tanaman tembakau rakyat di lapang yaitu ekstrak 1, ekstrak 2, ekstrak 3, dan ekstrak 4.Kegiatan penelitian ini dilaksanakan di Laboratorium Entomologi Balai Penelitian Tanaman Pemanis dan Serat, Malang mulai bulan Januari sampai dengan Desember 2011.Tujuan penelitian untuk memanfaatkan tembakau sebagai bahan aktif pembuatan pestisida nabati.Untuk tiap-tiap ekstrak di buat lima macam konsentrasi, yaitu 100%, 50%, 25%, 12,5%, 6,25%, 3,125%, dan 0 (kontrol. Serangga uji yang digunakan adalah hama pengisap daun tembakau Myzus persicae. Masing-masing ulangan dengan 20 serangga uji.Data yang diperoleh dari setiap pengamatan dianalisis menggunakan Analisis Probit. Hasil penelitian menunjukkan bahwa empat ekstrak daun tembakau yang diuji terbukti menyebabkan toksisitas pada kutu daun tembakau M. persicae. Ekstrak 3 merupakan ekstrak yang paling toksit dibanding 3 ekstrak yang lain.  LC50 ekstrak 1, ekstrak 2, ekstrak 3, dan ekstrak 4 berturut-turut 35,53%, 26,93%, 5,08%, dan 5,2%. Kata kunci: Ekstrak tembakau, pestisida botani, M. persicae.

  20. Isolation and characterization of polymorphic microsatellite loci in the green leafhopper Empoasca vitis Goethe (Homoptera).

    Science.gov (United States)

    Papura, D; Giresse, X; Chauvin, B; Caron, H; Delmotte, F; VAN Helden, M

    2009-05-01

    Eight dinucleotide microsatellite loci were isolated and characterized within the green leafhopper Empoasca vitis (Goethe) using an enrichment cloning procedure. Primers were tested on 171 individuals collected in the southwest of France from the vine plants. The identified loci were polymorphic, with allelic diversity ranging from two to 18 alleles per locus. Observed heterozygosities were from 0.021 to 0.760. These microsatellite markers should prove to be a useful tool for estimating the population genetic structure, host-plant specialization and migration capacity of this insect. © 2009 The Authors. Journal compilation © 2009 Blackwell Publishing Ltd.

  1. Kemampuan Pemangsaan Menochilus Sexmaculatus F. (Coleoptera: Coccinellidae) terhadap Rhopalosiphum Maidis Fitch (Homoptera: Aphididae)

    OpenAIRE

    Radiyanto, Indriya; Rahayuningtias, Sri; Widhianingtyas, Endah

    2011-01-01

    The objective of this research was to study the functional response of M. sexmaculatus. The hypothesis of this study was that age of predator and the numbers of prey will effect predation rate. To test this hypothesis, a set of prey (first and fourth instar and adult R. maidis) was separately placed together with first and fourth instar larval and adult female of M. sexmaculatus at different densities. The length of the exposure of the hosts were respectively 13, 14 and 2 hours for 1st instar...

  2. Mechanisms of Oryza sativa (Poaceae resistance to Tagosodes orizicolus (Homoptera: Delphacidae under greenhouse condition in Venezuela

    Directory of Open Access Journals (Sweden)

    Alex González

    2012-03-01

    Full Text Available Tagosodes orizicolus is one of the main plagues of rice in tropical America causing two types of damages, the direct one, feeding and oviposition effect, and an indirect one, by the transmission of the “Rice hoja blanca virus”. During 2006-2007 we carried out research under greenhouse conditions at Fundación Danac, Venezuela, in order to determine the mechanisms of antixenosis, antibiosis and tolerance to T. orizicolus, which could be acting in commercial varieties and advanced lines of the rice genetic breeding programs of INIA and Fundación Danac. The method of free feeding was used for the antixenosis evaluation, whereas the method of forced feeding was used for antibiosis evaluation (effect on survival and oviposition. Additionally, we used the indirect method based on biomass depression to estimate the tolerance. Some of the evaluated traits included: grade of damage, number of insects settling on rice plants, percentage of sogata mortality at the mature state, number of eggs in the leaf midrib and an index of tolerance. The results showed that rice genotypes possess different combinations of resistance mechanisms, as well as different grades of reactions. The susceptible control ‘Bluebonnet 50’ was consistently susceptible across experiments and the resistant control ‘Makalioka’ had high antixenosis and high antibiosis based on survival and oviposition. The rest of the genotypes presented lower or higher degrees of antixenosis and antibiosis for survival and viposition. The genotype ‘FD0241-M-17-6-1-1-1-1’ was identified with possible tolerance to the direct damage of sogata.Tagosodes orizicolus es una de las principales plagas del cultivo del arroz en América tropical causando dos tipos de daños a la planta, el directo, por efecto de la alimentación y oviposición; el indirecto, por la transmisión del virus de la hoja blanca del arroz. Durante el período 2006-2007 se llevó a cabo una investigación bajo condiciones de umbráculo en la Fundación Danac, Venezuela, con el objeto de determinar los mecanismos de resistencia de antixenosis, antibiosis y tolerancia a T. orizicolus que pudieran estar actuando en líneas avanzadas y cultivares del programa de mejoramiento enético de arroz de las instituciones INIA y Fundación Danac. Para la evaluación de antixenosis se utilizó el método de libre elección, para antibiosis (efecto sobre sobrevivencia y oviposición de los insectos el de alimentación forzada, adicionalmente se usó un método indirecto para estimar la tolerancia. Dentro de los principales parámetros determinados se encontraban: grado de daño, número de insectos posados sobre plantas de arroz, porcentaje de mortalidad de sogata en estado adulto, número de huevos y se calculó un índice de tolerancia con base en la biomasa. Los resultados mostraron que los genotipos de arroz evaluados poseen diferentes combinaciones en cuanto a los mecanismos de resistencia, así como el grado de su efecto. El testigo ‘Bluebonnet 50’ se mantuvo consistentemente susceptible en las evaluaciones y el testigo resistente ‘Makalioka’ fue el único genotipo que presentó alta antixenosis y alta antibiosis para sobrevivencia y oviposición. El resto de los genotipos presentaron un menor o mayor grado de resistencia de tipo antixenosis y antibiosis para sobrevivencia y oviposición. Se identificó el genotipo ‘FD0241-M-17-6-1-1-1-1’ con posible tolerancia al daño directo de sogata.

  3. Effects on the non-target aphid Aphis Gossypii Glover (Homoptera ...

    African Journals Online (AJOL)

    bych76-zhjh77

    2012-05-22

    May 22, 2012 ... 1The College of Plant Sciences, Jilin University, Changchun, China. 2State Key ... Aphididae), is a key pest on cotton that causes severe damage to crops .... the ELISA analysis, upon which the samples were weighed with an.

  4. A review of the leafhopper genus Jikradia with descriptions of four new species (Homoptera: Cicadellidae

    Directory of Open Access Journals (Sweden)

    Carolina Godoy

    1998-09-01

    Full Text Available The genus Jikradia Nielson extends from eastern North America to Central America and the Galapagos Islands. Four additional new species are described and illustrated: J. mexicana (Mexico J. longa (Costa Rica, Guatemala, Mexico, J. zurquiensis (Costa Rica and J. lizanoi (Costa Rica. J. mexicana general color is ochraceous; the aedeagus without seta-like spine. Jikradia longa, general color is light ochraceous; the aedeagus with long seta-like process subapically with three spine-like setae opposite to single subapical seta. Jikradia zurquiensis, general color brown; aedeagus with single seta-like process subapically with three small spine-like setae basad of single subapical setae on the opposite lateral margin of aedeagus. Jikradia lizanoi, general color brown; aedeagus asymmetrical, long, narrow, tube-like, in lateral aspect with sharply pointed apex, with two long seta-like processes subapically with four spine-like setae. A revised key to all known species, and subspecies, based on male genitalia, is also presented.Se describen e ilustran cuatro especies nuevas de Jikradia Nielson: J. mexicana (México J. longa (Costa Rica, Guatemala, México, J. zurquiensis (Costa Rica y J. lizanoi (Costa Rica. El trabajo inlcuye una clave ilustrada para todas las subespecies, con base en los aparatos genitales masculinos.

  5. The Hawaiian cave planthoppers (Homoptera: Fulgoroidea: Cixiidae - A model for rapid subterranean speciation?

    Directory of Open Access Journals (Sweden)

    Hannelore Hoch

    1997-01-01

    Full Text Available After the successful colonization of a single ancestral species in the Hawaiian Islands, planthoppers of the cixiid genus Oliarus underwent intensive adaptive radiation resulting in 80 described endemic species. Oliarus habitats range from montaneous rain forests to dry coastal biotopes and subterranean environments. At least 7 independant evolutionary lines represented by different species have adapted to lava tubes on Molokai (1, Maui (3, and Hawaii Island (3. Behavioral and morphological studies on one of these evolutionary lines on Hawaii Island, the blind, flight- and pigmentless Oliarus polyphentus have provided evidence for reproductive isolation between allopatric populations which may in fact be separate species. Significant differences in song parameters were observed even between populations from neighbouring lava tubes, although the planthoppers are capable of underground migration through the voids and cracks of the mesocavernous rock system which is extant in young basalt: after a little more than 20 years, lava tubes within the Mauna Ulu 1974 flow had been colonized by O. ‘polyphenius” individuals, most probably originating from a near-by forestkipuka. Amazingly, this species complex is found on the youngest of the Hawaiian Islands, with probably less than 0.5 m.y., which suggests rapid speciation processes. Field observations have led to the development of a hypothesis to match underground speciation with the dynamics of vegetational succession on the surface of active volcanoes. Planthopper range partitioning and geographic separation of populations by young lava flows, founder events and small population size may be important factors involved in rapid divergence.

  6. Behavior Performance of Diuraphis noxia (Homoptera: Aphididae) on Fungal Endophyte-Infected and Uninfected Perennial Ryegrass

    Science.gov (United States)

    S.L. Clement; D.G. Lester; A. Dan Wilson; K.S. Pike

    1992-01-01

    The behavior and performance of the Russian wheat aphid, Diuraphis noxia (Mordvilko), on fungal endophyte-infected and endophyte-free perennial ryegrass, Lolium perenne L., was investigated in the laboratory and field. Aphids did not select endophyte-free over endophyte-infected leaf sheaths and stem segments in petri dish preference tests....

  7. Duas novas espécies de Tunama fennah, 1968 (Homoptera, Cercopidae

    Directory of Open Access Journals (Sweden)

    Gervásio Silva Carvalho

    1990-01-01

    Full Text Available Two new brazilian species of Tunaima Fennah, 1968 are described: T. brunneoau-rantiaca sp.n. (from São Paulo and Paraná and T. brunneolutea sp.n. (from Paraná and Rio Grande do Sul.

  8. Diversity and Localization of Bacterial Endosymbionts from Whitefly Species Collected in Brazil

    Science.gov (United States)

    Marubayashi, Julio Massaharu; Kliot, Adi; Yuki, Valdir Atsushi; Rezende, Jorge Alberto Marques; Krause-Sakate, Renate; Pavan, Marcelo Agenor; Ghanim, Murad

    2014-01-01

    Whiteflies (Hemiptera: Aleyrodidae) are sap-sucking insect pests, and some cause serious damage in agricultural crops by direct feeding and by transmitting plant viruses. Whiteflies maintain close associations with bacterial endosymbionts that can significantly influence their biology. All whitefly species harbor a primary endosymbiont, and a diverse array of secondary endosymbionts. In this study, we surveyed 34 whitefly populations collected from the states of Sao Paulo, Bahia, Minas Gerais and Parana in Brazil, for species identification and for infection with secondary endosymbionts. Sequencing the mitochondrial Cytochrome Oxidase I gene revealed the existence of five whitefly species: The sweetpotato whitefly Bemisia tabaci B biotype (recently termed Middle East-Asia Minor 1 or MEAM1), the greenhouse whitefly Trialeurodes vaporariorum, B. tabaci A biotype (recently termed New World 2 or NW2) collected only from Euphorbia, the Acacia whitefly Tetraleurodes acaciae and Bemisia tuberculata both were detected only on cassava. Sequencing rRNA genes showed that Hamiltonella and Rickettsia were highly prevalent in all MEAM1 populations, while Cardinium was close to fixation in only three populations. Surprisingly, some MEAM1 individuals and one NW2 population were infected with Fritschea. Arsenopnohus was the only endosymbiont detected in T. vaporariorum. In T. acaciae and B. tuberculata populations collected from cassava, Wolbachia was fixed in B. tuberculata and was highly prevalent in T. acaciae. Interestingly, while B. tuberculata was additionally infected with Arsenophonus, T. acaciae was infected with Cardinium and Fritschea. Fluorescence in situ hybridization analysis on representative individuals showed that Hamiltonella, Arsenopnohus and Fritschea were localized inside the bacteriome, Cardinium and Wolbachia exhibited dual localization patterns inside and outside the bacteriome, and Rickettsia showed strict localization outside the bacteriome. This study is

  9. Resistance of soybean genotypes to Bemisia tabaci (Genn.) Biotype B (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Vieira, S S; Bueno, A F; Boff, M I C; Bueno, R C O F; Hoffman-Campo, C B

    2011-01-01

    The silverleaf whitefly Bemisia tabaci (Genn.) biotype B has become a serious problem for soybean cultivation because it can significantly reduce soybean productivity. The use of soybean cultivars resistant to whitefly attack is an important strategy in an integrated pest management (IPM) program. This study evaluated the preference for oviposition and colonization by B. tabaci biotype B on different soybean genotypes. In the free-choice test, the genotypes studied were 'IAC 17' and 'IAC 19' as the standards for resistance and 'IAC Holambra Stwart' as the standard for susceptibility, as well as BABR01-0492, BABR01-0173, BABR01-1259, BABR01-1576, BABR99-4021HC, BABR99-4021HP, 'Barreiras', 'Conquista', 'Corisco', 'BRS Gralha', PI274454, PI227687, and PI171451. In the no-choice test, the four best genotypes selected in the free-choice test, in addition to the susceptible and resistant standards were evaluated. Our data indicated 'Barreiras' as the most resistant genotype against B. tabaci biotype B. 'BRS Gralha', which was the least attractive to whitefly adults in the free-choice test, did not show resistance to insect attack when they were confined in cages in the no-choice test. Despite the high number of eggs observed, BABR01-1576 and BABR99-4021HC showed a reduced number of nymphs, indicating antibiosis. The genotypes with a high level of resistance can be used as a tool against B. tabaci in IPM or as a source of resistance in plant-breeding programs.

  10. REPRODUCTION OF THE FICUS WHITEFLY, SINGHIELLA SIMPLEX (HEMIPTERA: ALEYRODIDAE): A NEW INVASIVE PEST IN THE USA

    Science.gov (United States)

    Ficus Whitefly (Singhiella simplex) was first reported in Miami-Dade County in August 2007. This invasive pest causes infested plants to exhibit leaf yellowing, followed by leaf drop. The pest has been recorded on multiple ficus hosts including Ficus benjamina, F. altissima, F. bengalensis, F. micro...

  11. Characterization of Antixenosis in Soybean Genotypes to Bemisia tabaci (Hemiptera: Aleyrodidae) Biotype B.

    Science.gov (United States)

    Baldin, E L L; Cruz, P L; Morando, R; Silva, I F; Bentivenha, J P F; Tozin, L R S; Rodrigues, T M

    2017-08-01

    Bemisia tabaci biotype B (Gennadius) is one of the most important soybean pest worldwide. Herein, 15 soybean genotypes were evaluated, to characterize the occurrence of antixenosis to B. tabaci biotype B. Initially, a multiple-choice test with all genotypes was carried out, evaluating the settling and oviposition preference at 3 d after infestation, and the colonization by nymphs after 48 d of infestation. Subsequently, a no-choice test, using 14 genotypes, was conducted with infested plants individually, and the number of eggs was counted after 72 h. Then, 10 genotypes were selected (indicative of resistance and susceptibility), which were evaluated for whitefly settling 24, 48, and 72 h after infestation and for oviposition 72 h after infestation. The trichomes of the leaflets were characterized for density, size, and inclination to establish possible correlations with the settling and oviposition in the genotypes. In the first multiple-choice test, involving 15 genotypes, 'IAC-17,' 'IAC-19,' and UX-2569-159 expressed antixenosis against B. tabaci. 'Jackson,' 'P98Y11,' and PI-229358 exhibited the same behavior in the no-choice test. In the multiple-choice test, 'Jackson,' 'P98Y11,' and 'TMG1176 RR' were the least attractive and least used for oviposition. The antixenosis shown by 'Jackson,' 'P98Y11,' and PI-229358 may be related to the characteristics of the trichomes (lower density and inclined). Based on the experiments carried out, 'IAC-17,' 'IAC-19,' 'Jackson,' 'P98Y11,' PI-229358, TMG1176 RR, and UX-2569-159 are considered promising for resistance to B. tabaci biotype B and may be exploited in soybean breeding programs for resistance to insects. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Isolation and characterization of nine microsatellite loci from Bemisia tabaci (Hemiptera: Aleyrodidae) biotype B.

    Science.gov (United States)

    Hadjistylli, M; Schwartz, S A; Brown, J K; Roderick, G K

    2014-10-15

    Nine microsatellites were isolated from Bemisia tabaci (Gennadius) biotype B and screened across 60 individuals from two populations (biotype B) to examine polymorphism. Two to 12 alleles were observed per locus. Observed and expected heterozygosities ranged from 0.033 to 0.967 and 0.033 to 0.854, respectively. There was no significant deviation from Hardy-Weinberg equilibrium and no significant linkage disequilibrium between loci. One locus showed evidence for null alleles. These loci will be useful in future studies of the genetic structure of worldwide biotypes and gene flow analyses between and within biotypes of B. tabaci. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  13. Mortality of Bemisia tabaci biotype B (sternorrhyncha: aleyrodidae adults by aliphatic and aromatic synthetic sucrose esters

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    Mariangela Alves

    2008-12-01

    Full Text Available The B-strain of Bemisia tabaci Gennadius is a key pest of several crops and chemical control is the main control method used by growers, although reduction in efficacy due to insecticide resistance has already been reported. The aim of this work was to investigate the insecticidal effect of an array of synthetic sucrose esters with the aliphatic and aromatic groups on whitefly adults. Sucrose butyrate, caprate, octanoate, palmitate, oleate, octaacetate, phthalate, benzoate, and sucrose diacetate hexaisobutyrate were tested. The solutions were prepared and applied on the adults caught on yellow sticky traps using the Potter spray tower. Long-chains sucrose aliphatic esters were more effective against the silverleaf whiteflies and the highest mortality was obtained with sucrose oleate and sucrose octanoate. Since these compounds were tensoactive, sodium dodecylsulphate was also tested for the comparison but no effect was observed. Sucrose butyrate and other aliphatic and aromatic sucrose polyesters showed negligible effect on the silverleaf whiteflies.O biótipo B de B. tabaci Gennadius tem se destacado como uma praga-chave de diversas culturas. O controle químico tem sido a principal tática de controle utilizada, embora já se tenha observado redução na eficiência dos produtos devido ao desenvolvimento de resistência. Assim, o objetivo do presente trabalho foi avaliar o efeito de diversos ésteres de sacarose com grupos alifáticos ou aromáticos sobre adultos de mosca-branca. Butirato de sacarose, caprato, octanoato, palmitato, oleato, actaacetato, ftlato, benzoato e diacetato hexaisobutirato de sacarose foram testados. Soluções de éster de sacarose foram preparadas e aplicadas sobre adultos capturados em armadilhas adesivas utilizando Torre de Potter. Ésteres alifáticos de sacarose com longas cadeias foram mais efetivos contra mosca-branca e as maiores taxas de mortalidade foram obtidas com oleato e octanoato de sacarose. Uma vez que estes compostos são caracterizados como tensoativos, dodecilsulfato de sódio foi testado para comparação e não se observou qualquer efeito. Butirato de sacarose e outros poliésteres de sacarose alifáticos ou aromáticos foram praticamente inócuos para mosca-branca.

  14. Repellency, toxicity, and oviposition inhibition of vegetable extracts against greenhouse whitefly Trialeurodes vaporariorum (Westwood (Hemiptera: Aleyrodidae

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    Edgar Eduardo Mendoza-Garcia

    2014-03-01

    Full Text Available In a search for sustainable options of greenhouse whitefly Trialeurodes vaporariorum (Westwood management, the toxic and/or repellent potential of water, ethanolic, and acetonic extracts of Ambrosia artemisiifolia L. (Asteraceae, Comocladia engleriana Loes (Anacardiaceae, Piper auritum Kunth (Piperaceae, Raphanus raphanistrum L. (Brassicaceae, and Taraxacum officinale F.H. Wigg. aggr.* (Asteraceae were evaluated. Repellency was assessed by the cylinder method (olfactometer, while toxicity and oviposition inhibition were assessed by the leaf immersion method. Acetonic extracts did not cause any repellent or insecticidal effect. In contrast, 200 mg mL-1 water and ethanolic extracts of R. raphanistrum and ethanolic extract of A. artemisiifolia had the highest repellent activity (76%, 72%, and 69%, respectively although their activity decreased gradually over time. Ethanolic extracts of P. auritum (66% and R. raphanistrum (56% at 200 mg mL¹ were highlighted as being toxic, while the most effective in inhibiting oviposition were water extracts of R. raphanistrum (76.1% and P. auritum (72.0% and ethanolic extract of P. auritum (69.5%; however, concentrations lower than 60 mg mL-1 caused oviposition stimulation. Our results suggest that water and ethanolic extracts of R. raphanistrum and P. auritum represent a useful tool in integrated whitefly management.

  15. Temperature stress effects in Bemisia tabaci (Hemiptera: Aleyrodidae) type B whiteflies

    Science.gov (United States)

    Oxidative stress occurs in response to changes in the redox equilibiurm, which may be caused by increases in reactive oxygen species (ROS), a decrease in antioxidant protection or failure of cells to repair oxidative damage. ROS are either free radicals, reactive molecules containing oxygen atoms or...

  16. KISARAN INANG DAN DINAMIKA POPULASI Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae DI PERTANAMAN CABAI MERAH

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    . Hendrival

    2011-11-01

    Full Text Available The study of host range and population dynamic of B. tabaci in red chili pepper fiel dswas conducted in Sub-district of Pakem, District of Sleman, Province of Daerah Istimewa Yogyakarta during dry season of May-October 2009. The study of host plants of B. tabaci from the red chili pepper fields revealed that there were 27 species of host plants belong to 22 genera of 13 families including crops and weeds. The host plants belong to families of Araceae, Amaranthaceae, Asteraceae, Brassicaceae, Capparidaceae, Convolvulaceae, Euphorbiaceae, Lamiaceae, Oxalidaceae, Papilionaceae, Rubiaceae, Solanaceae and Sterculiaceae. The host plant families of Asteraceae and Euphorbiaceae had the most abundant population of B. tabaci. Geminivirus-like symptoms were found in the weeds of A. conyzoides and A. boehmerioides. Population of B. tabaci adults correlated with abundance of host plant species found in the red chili pepper fields. The population of B. tabaci in red chili pepper fields was affected by natural enemy population. Population dynamic of the parasitoid Eretmocerus sp. correlated with population dynamic of the parasitized nymph of B. tabaci. Parasitoid Eretmocerus sp. was potentially good in controlling population of B. tabaci nymph in red chili pepper fields.

  17. FECUNDITY OF FICUS WHITEFLY, SINGHIELLA SIMPLEX (HEMIPTERA: ALEYRODIDAE), AND ITS PREDATION BY DELPHASTUS CATALINAE (COLEOPTERA: COCCINELLIDAE)

    Science.gov (United States)

    Ficus Whitefly (Singhiella simplex) was first reported in Miami-Dade County in August 2007. This invasive pest causes infested plants to exhibit leaf yellowing, followed by leaf drop. The pest has been recorded on multiple ficus hosts including Ficus benjamina, F. altissima, F. bengalensis, F. micro...

  18. Transcriptome analysis of host-associated differentiation in Bemisia tabaci (Hemiptera: Aleyrodidae

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    Wen eXie

    2014-12-01

    Full Text Available Host-associated differentiation is one of the driving forces behind the diversification of phytophagous insects. In this study, host induced transcriptomic differences were investigated in the sweetpotato whitefly Bemisia tabaci, an invasive agricultural pest worldwide. Comparative transcriptomic analyses using coding sequence (CDS, 5’ and 3’ untranslated regions (UTR showed that sequence divergences between the original host plant, cabbage, and the derived hosts, including cotton, cucumber and tomato, were 0.11%-0.14%, 0.19%-0.26% and 0.15%-0.21%, respectively. In comparison to the derived hosts, 418 female and 303 male transcripts, respectively, were up-regulated in the original cabbage strain. Among them, 17 transcripts were consistently up-regulated in both female and male whiteflies originated from the cabbage host. Specifically, two ESTs annotated as Cathepsin B or Cathepsin B-like genes were significantly up-regulated in the original cabbage strain, representing a transcriptomic response to the dietary challenges imposed by the host shifting. Results from our transcriptome analysis, in conjunction with previous reports documenting the minor changes in their reproductive capacity, insecticide susceptibility, symbiotic composition and feeding behavior, suggest that the impact of host-associated differentiation in whiteflies is limited. Furthermore, it is unlikely the major factor contributing to their rapid range expansion/invasiveness.

  19. Field-Evolved Resistance of Bemisia tabaci (Hemiptera: Aleyrodidae) to Carbodiimide and Neonicotinoids in Pakistan.

    Science.gov (United States)

    Ahmad, Mushtaq; Khan, Rashid A

    2017-06-01

    The evolution of resistance to carbodiimide (a toxic metabolite of diafenthiuron) and four neonicotinoids imidacloprid, acetamiprid, thiamethoxam, and thiacloprid in the Pakistani populations of sweetpotato whitefly (Bemisia tabaci Gennadius) was monitored from 1996 to 2015 using a leaf-dip bioassay. Diafenthiuron, imidacloprid, and acetamiprid were introduced into Pakistani agriculture in mid-1990s and heavily used since then, because B. tabaci resistance and consequently control failures to conventional insecticides such as organophosphates, carbamates, and pyrethroids were widespread during the 1990s. According to the current studies, resistance to carbodiimide, imidacloprid, and acetamiprid during 1996-2010 and to thiamethoxam during 1999-2007 remained very low, but then it rose sharply, and by the year 2015, the B. tabaci resistance increased to very high levels. Among neonicotinoids, thiacloprid was the latest introduction in Pakistan in 2002. There was no thiacloprid resistance in 2002 and 2003, a low to moderate resistance during 2004-2006, and a very high resistance during 2007-2010 that even exceeded resistance to previous neonicotinoids. We may conclude that diafenthiuron and neonicotinoids remained effective against B. tabaci for 15 yr following their intensive use under field conditions, before a significant resistance, leading to their field failures, occurred in Pakistan. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  20. Repellent effect of alphacypermethrin-treated netting against Bemisia tabaci (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Martin, T; Kamal, A; Gogo, E; Saidi, M; Delétré, E; Bonafos, R; Simon, S; Ngouajio, M

    2014-04-01

    For > 20 yr, Bemisia tabaci Gennadius persists as a begomovirus vector and is a serious problem in tomato production in many parts of the world. In tropical countries, the use of netting to protect horticultural crops has proven to be an effective and sustainable tool against Lepidoptera but not against small insects. This study evaluated the repellent effect of AgroNet 0.9T, a 0.9-mm pore diameter and 40-mesh size netting treated with alphacypermethrin insecticide against B. tabaci. This pyrethroid insecticide is known to have toxic and repellent effects against mosquitoes and has been used for treatment of mosquito nets. Two nontreated netting materials were used as control: AgroNet 0.9NT with 0.9-mm pore diameter and 40-mesh size and AgroNet 0.4NT with 0.4-mm pore diameter and 80-mesh size. The behavior of B. tabaci and its parasitoid Encarsia formosa Gahan as they progressed through the treated netting was studied in the laboratory in choice and no-choice tests. The development of wild B. tabaci population on tomato plants protected by the same nets was followed in two field trials implemented in Njoro, Kenya. Results obtained with the no-choice tests showed a significant reduction of movement on the treated net with 40-mesh (19%) compared with nontreated netting (35 and 46% with 80- and 40-mesh, respectively). The mortality of B. tabaci was significantly higher (two-fold) in the test tube containing only the treated netting compared with the nontreated one. The repellent effect of the treated netting was also demonstrated against E. formosa, but it did not have this toxic effect. Unlike for B. tabaci, the treated and nontreated nets appeared to have a similar repellent effect on E. formosa in the choice test, which suggests a learning behavior of the parasitoid. In both field tests, B. tabaci population was significantly lower on tomato protected by the treated net compared with the same nontreated net. However there was no significant difference in B. tabaci population between the treated 0.9-pore diameter and the nontreated 0.4-pore diameter. We discussed these findings and their implications for the use of repellent netting in integrated pest management in horticulture and more specifically in vegetable production.

  1. [Occurrence of Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae) in the state of Maranhão, Brazil].

    Science.gov (United States)

    de Lemos, Raimunda N S; da Silva, Gilson S; Araújo, José R G; Das Chagas, Evandro F; Moreira, Aldenise A; Soares, Ana T M

    2006-01-01

    Aleurocanthus woglumi Ashby in citrus and mango crops in the state of Maranhão, Brazil, is recorded. Samples of 2003 and 2004 from several counties were identified and deposited in the Insect Collection of the Laboratório de Entomologia of the Núcleo de Biotecnologia Agronômica, Universidade Estadual do Maranhão.

  2. Reversal of resistance to pyriproxyfen in the Q biotype of Bemisia tabaci (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Wilson, Margaret; Moshitzky, Pnina; Laor, Einat; Ghanim, Murad; Horowitz, A Rami; Morin, Shai

    2007-08-01

    Pyriproxyfen, a juvenile hormone (JH) mimic, is a biorational insecticide that disrupts insect development. It is one of the principal insecticides being used to control Bemisia tabaci (Gennadius) on cotton, and has many environmentally positive attributes that make it compatible with integrated pest management (IPM) programs. In Israel, a high level of resistance to pyriproxyfen has been observed in several isolated regions. Here, tests were conducted to establish whether temporal refuges from exposure to pyriproxyfen could be useful for restoring the effectiveness of the compound. Resistance was found to decrease by a factor of 8 when exposure to pyriproxyfen was ceased for 13 generations. Reversal of resistance was accompanied with increased biotic fitness of the revertant colony. By incorporating experimental estimates of nymph survival, sex ratio, fecundity, egg hatching rate and developmental time, the seasonal cost per generation for resistant insects was estimated to be 25%. A genetic simulation model, optimized by empirical data from bioassays, predicted fitness cost per generation of 19% for resistant homozygous (RR) females and hemizygous (R) males, and produced rates of reversal similar to the experimental results. The model also predicted that, even after 5 years ( approximately 55 generations) without pyriproxyfen treatments, the frequency of the resistance allele (R) will still remain high (0.02). It is therefore concluded, on the basis of experimental and modeling results, that the effectiveness of temporal refuges for reversing development of resistance to pyriproxyfen in B. tabaci may be limited. Copyright (c) 2007 Society of Chemical Industry

  3. Use of biorational for the vegetable pest control in the north of Sinaloa

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    María Berenice González Maldonado

    2012-09-01

    Full Text Available In Sinaloa the vegetable and cucurbits production are important agricultural activities, so each year a high volume of chemicalinsecticides are applied to pest control that attack these crops. This paper present the main pests insects in the region, as wellas an analysis about effects of biorational insecticides on these pests. Was found that for control of Bemisia argentifolii Bellows & Perring (Hemiptera: Aleyrodidae is used Neem oil 0.2%., for kill nymphs of Bactericera cockerelli Sulc. (Homoptera: Psyllidae soursop Annona muricata L. (Annonales: Annonaceae at doses of 2500-5000 mg/L., for Liriomyza trifolii Burgess (Diptera: Agromyzidae neem seeds 2%., to Myzus persicae Sulzer (Hemiptera: Aphididae rapeseed oil at doses 920 g/L (2% v/v., to Frankliniella occidentalis Pergande (Thysanoptera: Thripidae spinosad (Conserve® 48-60 mg/L., and for Phthorimaea operculella Zeller (Lepidoptera: Gelechiidae granular viruses (105 OBs/mL combined with neem (DalNeem TM emulsifiable oil and NeemAzal TM -T/S at doses of 8 mg/L, everyone. The use of these products and the dose depends on the type of pest and crop. In general these products cause insect mortality greater than 95%, besides having low toxicity on natural enemies, so that these can be used individually or in combination in integrated pest control schemes against vegetable pests, and also for disease vectors insects in the northern of Sinaloa.

  4. Parasitism on Eriosoma lanigerum (Homoptera: Aphididae by Aphelinus mali (Hymenoptera: Encyrtidae on apple orchards, in Fraiburgo county, state of Santa Catarina, Brazil Parasitismo de Eriosoma lanigerum (Homoptera: Aphididae por Aphelinus mali (Hymenoptera: Encyrtidae em pomares de macieira, em Fraiburgo, SC

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    Lino Bittencourt Monteiro

    2004-12-01

    Full Text Available The parasitism of the woolly apple aphid (Eriosoma lanigerum Hausmann by Aphelinus mali (Hald. was evaluated in apple orchards cultivated with the varieties Gala and Fuji in Fraiburgo County, State of Santa Catarina, Southern Brazil. Colonies of the woolly apple aphid were evaluated during one year on 16 apple trees of each variety, starting in August 1999. The number of aphids at the mummy stage or presenting the orifice of the parasitoid emergence was recorded. Results have shown that A. mali parasitized more than 50% of the woolly apple aphids and occurred during the four seasons. It was concluded that that under these conditions no chemical control against the aphid is necessary for the apple varieties Gala and Fuji.O parasitismo de pulgão lanígero por Aphelinus mali (Hald. foi avaliado em pomares de macieira, contendo as variedades Gala e Fuji, em Fraiburgo, Santa Catarina. Foram avaliadas colônias de pulgão lanígero em 16 plantas de cada variedade, durante um ano, iniciando-se em agosto de 1999. Foi anotado o número de pulgões que se apresentavam no estágio de múmia ou apresentavam o orifício de emergência do parasitóide. Os resultados mostraram que A. mali parasitou mais de 50% dos pulgões lanígeros, nas quatro estações do ano. Concluiu-se que, nestas porcentagens de parasitismo, não é necessária nenhuma intervenção química para o controle do pulgão lanígero, em ambas as variedades.

  5. Comparative profiling of microRNAs in the winged and wingless English grain aphid, Sitobion avenae (F.) (Homoptera: Aphididae)

    Science.gov (United States)

    English green aphid, Sitobion avenae (F.), show a classic polyphenic wing dimorphism among isogenic adults that is an intriguing model for the study of morphological plasticity in response to the environment. Short non-coding microRNA (miRNA) molecules regulate gene expression by post-transcriptiona...

  6. Projection pursuit nonparametric regression applied to field counts of the aphid Macrosiphum euphorbiae (Homoptera: Aphididae) on tomato crops in greenhouses.

    Science.gov (United States)

    Boll, R; Lapchin, L

    2002-04-01

    The number of plants that sampling requires in aphid population studies often exceeds one hundred. Thus, only quick and nondestructive methods can be used to sample this pest in a reasonable time interval. We propose a visual method for estimating the density of the aphid Macrosiphum euphorbiae (Thomas) on tomato plants reared in greenhouses. After approximately 1min of visual observation plants can be assigned to abundance classes, the boundaries of which are roughly the powers of square root 10. Precise counts were collected simultaneously on sets of reference plants from the same greenhouse. Projection pursuit nonparametric regression was then used to provide unbiased estimates of aphid densities from the abundance classes and several easily gathered explanatory variables. The robustness of the method was evaluated by testing the models on the complementary data sets from plants in which the aphid densities were precisely counted. In both single and twin-row cultural conditions, for the reference and complementary data sets, the order of magnitude of the error was less than one class rank per plant. The investigation time was reduced by approximately 10-fold compared with the exact counting method. This easy-to-teach field method could be useful in large-scale population surveys and for optimizing integrated pest management strategies.

  7. Morphostructural analysis of the male reproductive system and DNA barcoding in Balclutha brevis Lindberg 1954 (Homoptera, Cicadellidae).

    Science.gov (United States)

    Vitale, D G M; Viscuso, R; D'Urso, V; Gibilras, S; Sardella, A; Marletta, A; Pappalardo, A M

    2015-12-01

    Balclutha brevis Lindberg 1954 is an allochthonous leafhopper infesting an invasive grass, Pennisetum setaceum, in Sicily and in mainland Europe; therefore, this species could compete with populations of native species, thus contributing to the loss of biodiversity. Considering the ecological implications of B. brevis, investigations on all its biological aspects represent, therefore, a premise for further studies in applied sciences. Based on the lacking ultrastructural data about the reproductive systems of the Auchenorrhyncha, we carried out morphostructural investigations on the male reproductive system of B. brevis. Further, a first report of DNA barcoding analysis (amplification and sequencing of Cytochrome Oxidase I gene) has also been performed to characterize B. brevis compared to other congeneric species. From a morphological point of view, the male reproductive system of B. brevis has an organization comparable to the general anatomical features of most of the Auchenorrhyncha species; however, comparing our data with those concerning the different groups of Cicadomorpha, some considerations are discussed. As for the histological and ultrastructural investigations, our results show a secretory activity of the various examined structures, mainly in the lateral ejaculatory ducts and in the accessory glands. The latter, in particular, show morphostructural differences comparing the distal tract to the proximal one; moreover, the histochemical techniques showed the possible presence of a lipid component in the peculiar cytoplasmic granules found in the gland cells. The significance of these findings in the accessory glands is discussed. Finally, the ultrastructural features found in the seminal vesicles are different from those of the lateral ejaculatory ducts and are indicative of the different roles played by these structures in the organization of the spermatozoa bundles. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. A new species of Scaris from southeastern Brazil, with notes on S. nessimiani and S. bahiensis (Homoptera: Cicadellidae

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    Luci Boa Nova Coelho

    2002-06-01

    Full Text Available Anew leafhopper species, Scaris angrensis sp.nov., is described and illustrated based on an adult male from Angra dos Reis, State of Rio de Janeiro, southeastern Brazil. The holotype is deposited in the entomological collection of Museu Nacional, Universidade Federal do Rio de Janeiro, Brazil. The new species seems to be more closely related to S. bahiensis because of its single ventral process on the aedeagal base, being distinguished from that by the apical shape of the stylus. A problem related to the illustrations in the original description of S. nessimiani and S. bahiensis is herein correctedSe describe e ilustra un nuevo cicadélido, Scaris angrensis sp.nov., basado en un macho adulto de Angra dos Reis, litoral sur del Estado de Rio de Janeiro. El holotipo está depositado en la colección de insectos del Museu Nacional, Universidade Federal do Rio de Janeiro, Brasil. La nueva especie parece estar relacionada más estrechamente con S. bahiensis debido a su "proceso" ventral en la base del edeago, difiriendo en la forma del ápice del estilo. Se corrige un problema relacionado con la descripción original de S. nessimiani y de S. bahiensis

  9. A new genus and new species of felt scales (Homoptera: Coccinea: Eriococcidae from Tierra del Fuego (Chile

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    Ilya A. Gavrilov-Zimin

    2016-10-01

    Full Text Available Telmatococcus igniumterrae gen. nov. et sp. nov. is described and illustrated based on the material collected from a sphagnum bog in the extreme southern part of South America (Tierra del Fuego. The new monotypic genus differs from all known genera of Eriococcidae in having short cylindrical truncated setae of the anal apparatus and pouches with numerous quinquelocular pores near the anal apparatus. The habitat of the new taxon is characterized.

  10. The taxonomy and biogeography of the nasuta group of the genus Baeturia Stål, 1866 (Homoptera, Tibicinidae)

    NARCIS (Netherlands)

    Boer, de A.J.

    1982-01-01

    The name nasuta group is proposed here for eight New Guinean species of the genus Baeturia Stål, 1866, for which a monophyletic origin is made plausible. Seven of these species are redescribed, and one, B. intermedia, is described as new. Distribution maps and a key to the males are presented. The

  11. Lady beetles (Coleoptera: Coccinellidae) from Chinese hemlocks infested with the hemlock woolly adelgid, Adelges tsugae Annand (Homoptera: Adelgidae)

    Science.gov (United States)

    Gouyue Yu; Michael E. Montgomery; Defu Yao

    2000-01-01

    Fifty-four species of lady beetles were collected from three Chinese hemlock species, Tsuga dumosa (D. Don) Eichler, T. forrestii Downie and T. chinensis (Franchet) Pritzel, in Yunnan, Sichuan and Shaanxi provinces of China as part of a search for natural enemies of the hemlock woolly adelgid, Adelges tsugae Annand. Twenty new species are described: Clitostethus...

  12. Tanggap fungsional Menochilus sexmaculatus Fabricius (Coleoptera: Coccinellidae terhadap Aphis gossypii (Glover (Homoptera: Aphididae pada umur tanaman cabai berbeda

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    Novri Nelly

    2015-09-01

    Full Text Available The lady beetle, Menochilus sexmaculatus is one of the biological control agents that can be used to control aphids. Presently, there is a lack of information about the effectiveness of this beetle to control aphids. The objective of this research was to study the functional response of M. sexmaculatus on Aphis gossypii at different ages of plants. All preys were exposed to one M. sexmaculatus adult for an hour at five different densities of aphids (10, 20, 30, 40, and 50 individuals is four different ages of chilli plants (2,4,6, and 8 weeks. Data were analyzed by ANOVA and logistic regression to determine the type of functional response. The results showed that the ability of M. sexmaculatus to prey was not significant at 2 to 4 and 6 to 8 weeks old chilli plants. At 2 week old chilli plants M. sexmaculatus showed type I of functional response, while at 4, 6 and 8 weeks the functional response were type III.

  13. Aphids (Homoptera, Aphidodea inhabiting the trees Crataegus x media Bechst. in the urban green area. Part I. The population dynamics

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    Bożena Jaśkiwicz

    2013-12-01

    Full Text Available The studies were conducted in the years 1999-2001 in the green areas of Lublin, on the trees of Crataegus x media Bechst. The purpose of the studies was to establish the species composition and the population dynamics of aphids inhabiting hawthorn in the street and park sites. The studies found out the presence of four aphid species on the examined trees, namely Aphis pomi De Geer, aphids from the genus Dysaphis Börn., Ovatus crataegarius (Walk. and Rhopalosiphum insertum (Walk.. More aphid species and bigger populations were found in the street site (A as compa red with the park site (B.The weather conditions (air temperatures of over 30°C and stormy rainfalls limited the population of all aphid species. On the other hand, a mild winter and a warm spring with the rainfalls within the norm caused that the number of aphids decreased considerably.

  14. Clonal turnover of MACE-carrying peach-potato aphids (Myzus persicae (Sulzer), Homoptera: Aphididae) colonizing Scotland.

    Science.gov (United States)

    Kasprowicz, L; Malloch, G; Foster, S; Pickup, J; Zhan, J; Fenton, B

    2008-04-01

    Peach-potato aphids, Myzus persicae (Sulzer), collected in Scotland in the years 1995 and 2002-2004 were characterized using four microsatellite loci and three insecticide resistance mechanisms. From 868 samples, 14 multilocus genotypes were defined (designated clones A-N). Five of these (denoted A, B, H, M and N) carried modified acetylcholinesterase (MACE) resistance, the most recent resistance mechanism to have evolved in M. persicae. The current paper shows that the continued presence of MACE aphids is due to turnover, as clones A and B were replaced in field samples by clones H, M and N in later seasons. Thus, insecticide-resistant populations in Scotland can be attributed to multiple waves of rapid clone colonisations and not to the continued presence of stable resistant clones or mutation or sexual recombination in local populations. The MACE clones carried varying levels of the other insecticide resistance mechanisms, kdr and esterase. The presence of these mechanisms could alter the clones success in the field depending on insecticide spraying (positive selection) and resistance fitness costs (negative selection).

  15. CONTROLE QUÍMICO DO PULGÃO MYZUS PERSICAE (SULZER,1776 (HOMOPTERA-APHIDIDAE NA CULTURA DO FUMO

    Directory of Open Access Journals (Sweden)

    Manoel Fernando Sigaran Tarragó

    1994-01-01

    Full Text Available RESUMO Estudou-se a ação de diferentes inseticidas sobre populações do pulgão, Myzus persicae, em lavouras de fumo da Agro Comercial Fumageira S. A., var. Sumatra, no Município de Cruz das Almas - BA. Foram realizados dois ensaios, um em dezembro de 1991 e o outro em fevereiro de 1992, e nas duas oportunidades mostraram-se eficientes os inseticidas Acefate 750 PS, Pirimicarb 500 PM e Metamidofos 600 CE.

  16. The population dynamics of Fiorinia fioriniae (Targioni) (Homoptera: Diaspididae) and factors affecting its seasonal abundance in Egypt.

    Science.gov (United States)

    Mesbah, H A; Fata, A A; Moursi, K E; Mourad, A K; Abdel-Razak, S I

    2001-01-01

    Fiorinia fioriniae (Targioni) was observed attacking Callistemon lanceolatus at the Experimental Farm of the Agricultural Research Station and Ruscus hypoglossum at Antoniades park in Alexandria Governorate; Egypt. The infestation rate on Ruscus hypoglossum, reached its maximum (98.0%) during autumn months, while the minimum rate 68.3%, was recorded during summer months. The fluctuating population density of F. fioriniae showed three distinct peaks. The first peak of 731.0 individuals/10 branches was recorded in October 1998, the second (734.1) in December 1998, and the third, (506.9) in April 1999. The highest number of counted insects (1991.1/plant) was observed during the autumn season, followed by winter (1467.9), spring (978.2) seasons and the least number (271.6/plant) was recorded in summer. On the contrary, the highest rate of infestation by the immature stages was recorded during the winter season, followed by spring, summer and autumn seasons (42.8, 29, 24.6 and 21.9%) of the total counted insects, respectively. The scale insect has been parasitized with the aphelinid species Encarsia citrina (Aphelinidae) with a maximum rate of 28.1 of the total count during August. The statistical analysis was performed for determining the relationship between the prevailing weather factors of daily mean temperature, daily relative humidity, wind speed and day-light in one hand and the population activity of F. fioriniae on R. hypoglossum plants on the other hand.

  17. Comparison of AC electronic monitoring and field data for estimating tolerance to Empoasca kraemeri (Homoptera: Cicadellidae) in common bean genotypes.

    Science.gov (United States)

    Serrano, M S; Backus, E A; Cardona, C

    2000-12-01

    Two methods for estimating the tolerance of common bean genotypes to Empoasca kraemeri Ross & Moore were compared, using a yield trial carried out at Centro Internacional de Agricultura Tropical (CIAT), Cali, Colombia, versus stylet penetration tactics measured by AC electronic feeding monitors. A stylet penetration index was devised based on principal component scores of three penetration tactics identified (pulsing laceration, cell rupturing, and lancing sap ingestion), combined with knowledge of the hopperburn symptoms caused by each tactic. Tolerant genotypes, as classified by the CIAT yield index, showed significantly more unprotected yield and lower hopperburn scores than the susceptible control. They also induced performance of less pulsing laceration (the tactic considered most damaging to the plant), and more of the other two, mitigating tactics, especially cell rupturing. When index values were calculated for each genotype, stylet penetration index values matched those of the yield index for three out of five genotypes: two EMP-coded tolerant lines ('EMP 385' and 'EMP 392') and the susceptible control 'BAT 41'. Thus, for these three genotypes, all subsequent hoppereburn symptoms are predictable by the type of feeding behavior performed on them. 'Porrillo Sintético' and 'EMP 84', considered borderline genotypes by the yield index, were overestimated and underestimated respectively, by the stylet penetration index. We postulate that, for these two genotypes, plant physiological responses to feeding (either compensatory or heightened sensitivity, respectively) synergize with type of feeding performed to generate the overall hopperburn condition. This multivariate analysis of electronic monitoring data was successfully used to devise an index of resistance. The implications of using the stylet penetration index and the advantages of using electronic monitoring in a bean-breeding program are discussed.

  18. Bacterial symbionts, Buchnera, and starvation on wing dimorphism in English grain aphid, Sitobion avenae (F. (Homoptera: Aphididae

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    Fangmei eZhang

    2015-05-01

    Full Text Available Wing dimorphism in aphids can be affected by multiple cues, including both biotic (nutrition, crowding, interspecific interactions, the presence of natural enemies, maternal and transgenerational effects, and alarm pheromone and abiotic factors (temperature, humidity, and photoperiod. The majority of the phloem-feeding aphids carry Buchnera, an obligate symbiotic proteobacteria. Buchnera has a highly reduced genome size, but encode key enzymes in the tryptophan biosynthetic pathway and is crucial for nutritional balance, development and reproduction in aphids. In this study, we investigated the impact of two nutritional-based biotic factors, symbionts and starvation, on the wing dimorphism in the English grain aphid, Sitobion avenae, a devastating insect pest of cereal crops (e.g., wheat worldwide. Elimination of Buchnera using the antibiotic rifampicin significantly reduced the formation of winged morphs, body mass and fecundity in S. avenae. Furthermore, the absence of this primary endosymbiont may disrupt the nutrient acquisition in aphids and alter transgenerational phenotypic expression. Similarly, both survival rate and the formation of winged morphs were substantially reduced after neonatal (< 24h old offspring were starved for a period of time. The combined results shed light on the impact of two nutritional-based biotic factors on the phenotypic plasticity in aphids. A better understanding of the wing dimorphism in aphids will provide the theoretical basis for the prediction and integrated management of these phloem-feeding insect pests.

  19. Host plant effects on development and reproduction of the glassy-winged sharpshooter, Homalodisca vitripennis (Homoptera: Cicadellidae)

    Science.gov (United States)

    Development, survivorship, longevity, reproduction and life table parameters of the glassy-winged sharpshooter, Homalodisca vitripennis (Germar), were examined in the laboratory using three host plants, sunflower (Helianthus annuus L.), Chrysanthemum morifolium L. and euonymus (Euonymus japonica Thu...

  20. Effects of temperature on biology and life table parameters of the Asian citrus psyllid, Diaphorina citri Kuwayama, (Homoptera: Psyllidae)

    National Research Council Canada - National Science Library

    Liu Y H; Tsai J H

    2000-01-01

    The development, survivorship, longevity, reproduction, and life table parameters of the Asian citrus psyllid, Diaphorina citri Kuwayama were evaluated at 10 C, 15 C, 20 C, 25 C, 28 C, 30 C and 33 C...

  1. The taxonomy and biogeography of the bloetei group of the genus Baetura Stål, 1866 (Homoptera, Tibicinidae)

    NARCIS (Netherlands)

    Boer, de A.J.

    1989-01-01

    The bloetei group is proposed for a monophyletic group of 18 species of the genus Baeturia Stål, 1866. Fifteen species are described as new ( B. bilebanarai, B. bismarckensis, B. bloetei, B. boulardi, B. brandti, B. cristovalensis, B. gressitti, B. macgillavryi, B. manusensis, B. marginata, B.

  2. Resistance of Endophyte-Infected Plants of Tall Fescue and Perennial Ryegrass to the Russian Wheat Aphid (Homoptera: Aphididae)

    Science.gov (United States)

    S.L. Clement; K.S. Pike; W.J. Kaiser; A. Dan Wilson

    1991-01-01

    Fewer aphids of the Russian wheat aphid, (Mordvilko), were found on tall fescue and perennial ryegrass plants harboring systemic fungal endophytes than on endophyte-free plants in laboratory tests. These results indicate that enhanced resistance in some perennial grasses to D. noxia is associated with the presence of endophytic fungi.

  3. Inheritance Mode and Realized Heritability of Resistance to Imidacloprid in the Brown Planthopper, Nilaparvata lugens (Stal) (Homoptera: Delphacidae)

    Science.gov (United States)

    BACKGROUND: The brown planthopper, Nilaparvata lugens (Stål) is a serious pest which causes enormous losses to the rice crop in Asia. The genetic basis of imidacloprid resistance was investigated in N. lugens. RESULTS: The resistant strain, selected for imidacloprid resistance from a laboratory pop...

  4. Chemical Composition and Behavioral Effects of Five Plant Essential Oils on the Green Pea Aphid Acyrthosiphon pisum (Harris) (Homoptera: Aphididae).

    Science.gov (United States)

    Kasmi, Abir; Hammami, Majdi; Raoelison, Emmanuel G; Abderrabba, Manef; Bouajila, Jalloul; Ducamp, Christine

    2017-05-01

    Essential oils (EOs) from Schinus molle, Helichrysum gymnocephalum, Cedrelopsis grevei and Melaleuca viridiflora, four aromatic and medicinal plants, are commonly used in folk medicine. EOs were characterized by gas chromatography/mass spectrometry (GC/MS) and quantified by gas chromatography-flame ionization detection (GC-FID); then evaluated for their behavioral effects on adults of the green pea aphid Acyrthosiphon pisum (Harris) using a Perspex four-armed olfactometer in order to test the compatibility of their use as phytoinsecticides to control this insect pest. Our results showed that the EOs from the leaves of S. molle, M. viridiflora and C. grevei did not change aphids' behavior. However, S. molle fruits EO seemed to be attractive while H. gymnocephalum leaves EO exhibited repellency towards aphids at a dose of 10 μl. The major compounds in S. molle fruits EO were 6-epi-shyobunol (16.22%) and d-limonene (15.35%). While, in H. gymnocephalum leaves EO, 1,8-cineole was the main compound (47.4%). The difference in aphids' responses to these two EOs could be attributed to the differences in their compositions. Our findings suggest that these two EOs have potential applications for the integrated pest management of A. pisum (Harris). © 2017 Wiley-VHCA AG, Zurich, Switzerland.

  5. Primer registro de "la mosca negra de los cítricos" Aleurocanthus woglumi (Hemiptera: Aleyrodidae en la Argentina First record of the citrus blackfl y Aleurocanthus woglumi (Hemiptera: Aleyrodidae in Argentina

    Directory of Open Access Journals (Sweden)

    Silvia N. López

    2011-12-01

    Full Text Available Aleurocanthus woglumi Ashby es una especie polífaga que ataca principalmente cultivos de Citrus spp. El objetivo de este trabajo es dar a conocer la primera detección de A. woglumi en Argentina. Los especímenes estudiados fueron recolectados en cultivos de pomelo en Tres Lagunas, departamento de Pilagá, Formosa, en febrero de 2011.Aleurocanthus woglumi Ashby is a polyphagous pest that attacks mainly Citrus spp. The objective of this paper is to report the first detection of this species in Argentina. Studied specimens were collected from grapefruit crops at Tres Lagunas, department of Pilagá, Formosa, in February, 2011.

  6. Biology of the citrus blackfly, Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae), in three host plants; Biologia da mosca-negra-dos-citros, Aleurocanthus woglumi Ashby (Hemiptera: Aleyrodidae), em tres plantas hospedeiras

    Energy Technology Data Exchange (ETDEWEB)

    Pena, Marcia R.; Silva, Neliton M. da [Universidade Federal do Amazonas (UFAM), Manaus, AM (Brazil).Lab. de Entomologia Agricola], e-mail: marciarpena@yahoo.com.br, e-mail: nmarques@ufam.edu.br; Venframim, Jose D.; Haddad, Marineia de L. [Escola Superior de Agricultura Luiz de Queiroz (ESALQ/USP), Piracicaba, SP (Brazil). Lab. de Resistencia de Plantas e Plantas Inseticidas], e-mail: jdvendra@esalq.usp.br, e-mail: mlhaddad@esalq.usp.br; Lourencao, Andre L. [Instituto Agronomico de Campinas (IAC), SP (Brazil)], e-mail: andre@iac.sp.gov.br

    2009-03-15

    The citrus blackfly, Aleurocanthus woglumi Ashby, was detected in Brazil in 2001. The aim of this research was to evaluate the biology, biometry and host preference of A. woglumi in sweet orange, acid lime Tahiti and mango. Experiments were set in laboratory conditions with insects collected in rangpur lime plants in Manaus, State of Amazonas, from January to June of 2006. The following parameters were evaluated: number of spirals (ovo positions) and eggs per plant, number of eggs by spiral per plant, survival of the immature (eggs, 1st, 2nd, 3rd and 4th instars), and length and survival of the immature stage. The mean embrionary period was 15 days for the three hosts. The 4th nymph (puparium) was the longest during nymph development. Second and third instars had the highest survival. The mean length of the egg-adult cycle was 70 days for the three hosts evaluated. The eggs were laid in a spiral shape on the adaxial leaf surface. The 1st instars moved to short distances from the spiral, while the 2nd, 3rd and 4th are sessile and have bristles on the whole body. Based on the highest oviposition and the highest survival of the immature stage of the citrus blackfly in acid lime Tahiti, this plant can be considered the most suitable host to A. woglumi. (author)

  7. Effect of Two Entomopathogenic Fungi in Controlling Aleurodicus cocois (Curtis, 1846 (Hemiptera: Aleyrodidae Efecto de Dos Hongos Entomopatógenos en el Control de Aleurodicus cocois (Curtis, 1846 (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Elizabeth Núñez del Prado

    2008-03-01

    Full Text Available Aleurodicus cocois (Curtis, 1846, the coconut whitefly, is a very damaging pest in Peru, mainly in avocado trees (Persea americana Mill.. It has been determined that entomopathogenic fungi can infect and kill white flies and can be used as biological control agents. The object of this research was to determine if there is any synergic action of the entomopathogenic fungi Paecilomyces fumosoroseus (Wize Brown & Smith 1957 and Verticillium lecanii (Zimmerman, 1892 Viégas 1939, in controlling A. cocois. Plastic sterile dishes were prepared where 5 mL 2% agar were used for each stage; leaves infested with A. cocois were placed upon these. Three different treatments were applied by sprinkling: P. fumosoroseus (P, V. lecanii (V or the mixture of the two fungi. These treatments were evaluated at one, two and seven days in the case of nymph I and eggs, and after four, eight and 12 days for nymph II, NIII and NIV. The lethal effect of V. lecanii on the second nymph instar of A. cocois was better than that of P. fumosoroseus and than the mixture of both fungi; the highest mortality percentage appeared from day eight to day 12. A small increase was observed in the effect of the mixture of the two entomopathogenic fungi on the IV nymph instar; and the effect of P. fumosoroseus was the lowestAleurodicus cocois (Curtis, 1846, la mosca blanca del cocotero, constituye una plaga muy importante en el Perú, principalmente en el palto (Persea americana Mill.. Se ha determinado que los hongos entomopatógenos pueden infectar y matar a la mosca blanca, por lo que podrían ser usados como agentes de control biológico. El objetivo del presente trabajo fue determinar si existe alguna acción conjunta de dos hongos entomopatógenos Paecilomyces fumosoroseus (Wize Brown & Smith 1957 y Verticillium lecanii (Zimmerman, 1892 Viégas 1939, en el control de A. cocois. Para ello se prepararon previamente placas de plástico estériles en las que se sirvieron aproximadamente 5 mL de agar al 2%, donde se colocaron hojas infestadas con A. cocois, aplicándose tres tratamientos por aspersión: P. fumosoroseus (P, V. lecanii (V y la mezcla de los dos hongos, los cuales se evaluaron en el caso de Ninfa I y huevos después de uno, dos y siete días, y para la Ninfas II, NIII y NIV cada cuatro, ocho y 12 días. El efecto de mortalidad de V. lecanii sobre el segundo estadío ninfal de A. cocois fue mejor que P. fumosoroseus y que la mezcla de ambos hongos, ya que el mayor porcentaje de mortalidad se presentó desde el octavo día hasta el día 12. En el caso del IV estadío ninfal se observó un ligero incremento en el efecto al combinarse los dos hongos entomopatógenos evaluados, siendo menor el efecto en P. fumosoroseus

  8. Indutores de resistência à mosca-branca Bemisia tabaci Biótipo B (GENN., 1889 (Hemiptera: Aleyrodidae em soja Resistance inducers to the whitefly Bemisia tabaci Biotype B (GENN., 1889 (Hemiptera: Aleyrodidae in soybeans

    Directory of Open Access Journals (Sweden)

    Jair Campos Moraes

    2009-10-01

    Full Text Available Objetivou-se, neste trabalho, avaliar o efeito da aplicação de indutores na resistência de duas cultivares de soja à mosca-branca Bemisia tabaci biótipo B. O experimento foi conduzido no Departamento de Entomologia - UFLA. As sementes de soja, cultivar IAC-19 e MONSOY-8001, foram previamente tratadas com o fungicida captan. Foram testados os seguintes tratamentos: T1- irrigação no solo, ao redor das plantas de cada vaso, de 250 mL de solução de ácido silícico a 1%; T2- pulverização das plantas, até o ponto de escorrimento, com solução a 0,3% de acibenzolar-s-methyl; T3- pulverização das plantas, até o ponto de escorrimento, com calda a 0,24% de pyraclostrobin+epoxiconazole e T4- testemunha. As plantas foram infestadas com 100 adultos da mosca-branca por vaso que liberados oito dias após a aplicação dos tratamentos. Avaliaram-se o número de ovos na face abaxial de cada folha, que foi marcada para posterior avaliação de ninfas; teores de taninos e de lignina; peso seco das raízes e da parte aérea. Não houve diferença para número de ovos e ninfas entre as cultivares de soja, porém, a viabilidade média de B. tabaci foi menor a cultivar IAC-19. O cultivar de soja IAC-19 demonstrou moderada resistência ao biótipo B de B. tabaci. A aplicação de silício ou acibenzolar-s-methyl induz um aumento no teor de lignina na cultivar de soja IAC-19.The objective of this paper was to evaluate the effect of the application of inducers on the resistance of two soybean cultivars to the whitefly B. tabaci Biotype B. The experiment was carried out at the Entomology Department - UFLA. The soybean seeds of cultivars IAC-19 and MONSOY-8001 were previously treated with Captan fungicide. The following treatments were tested: T1- irrigating the soil around the plants of each pot with 250 mL of solution of 1% silicic acid; T2- spraying of the plants, to the 'point of dripping', with a solution of 0.3% acibenzolar-s-methyl; T3- spraying of the plants, to the 'point of dripping', with a solution of 0.24% pyraclostrobin+epoxiconazole, and T4- control. The plants were infested with 100 adult whiteflies that were released eight days after applying the treatments. The number of eggs on the abaxial face of each leaf, which was marked for further evaluation of nymphs, tannin and lignin contents, dry weight of the aerial parts and roots, was evaluated. There was no difference for the number of eggs and nymphs among the soybean cultivars. Nevertheless, the average survival rate of B. tabaci was lower on cultivar IAC-19. The application of silicon or acibenzolar-s-methyl induces an increase in lignin content in the soybean cultivar IAC-19.

  9. Efficiency of neem oil nanoformulations to Bemisia tabaci (GENN. Biotype B (Hemiptera: AleyrodidaeEficiência de nanoformulações a base de óleo de nim sobre Bemisia tabaci (GENN. Biótipo B (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Sheila Salles Carvalho

    2012-04-01

    Full Text Available The nanotechnology, through encapsulation of active ingredients, has showed an important way to avoid problems with quickly degradation of the pesticide molecules. Thus, neem (Azadirachta indica oil nanoformulations containing ?-ciclodextrin and poli-?-caprolactone (PCL were tested as to their control efficiency against eggs and nymphs of Bemisia tabaci (Genn. biotype B reared in soybean. The Lethal Concentration (LC50 was estimated using a commercial neem oil (Organic Neem® on first-instar nymphs to establish the adequate volume of the nanoformulations per treatment. After that, they were sprayed on eggs and first-instar nymphs in laboratory and greenhouse and on third-instar nymphs in greenhouse. The commercial neem oil and distilled water were used as controls. Egg viability was not affected by any treatment. Among six nanoformulations, only one was efficient against the first-instar nymphs in laboratory conditions. However, its effective period was not increased as expected. In greenhouse, first-instar nymphs were more affected by two nanoformulations which were significantly different of the commercial neem oil - the most effective one. No mortality differences among the formulations in the third-instar test were observed. The nanoformulations were less efficient to control the B. tabaci biotype B nymphs than the commercial neem oil. A nanotecnologia, através do encapsulamento de ingredientes ativos, tem-se revelado uma importante estratégia para evitar problemas com a rápida degradação de moléculas inseticidas. Assim, nanoformulações à base de óleo de nim (Azadirachta indica utilizando os polímeros ?-ciclodextrina e poli-?-caprolactona (PCL foram testadas quanto a sua eficiência de controle de ovos e ninfas de Bemisia tabaci (Genn. biótipo B mantidas em soja. Foi estimada a CL50 utilizando uma formulação comecial de óleo de nim (Organic Neem® sobre ninfas em 1º ínstar da qual se estipulou o volume das nanoformulações a serem utilizadas por tratamento. Depois disso, os tratamentos foram aplicados sobre ovos e ninfas de 1º ínstar em laboratório e em casa de vegetação e sobre ninfas de 3º ínstar em casa de vegetação. O óleo comercial e água destilada foram utilizados como controles. A viabilidade dos ovos não foi afetada por qualquer dos tratamentos. Das seis formulações testadas, somente uma delas mostrou-se eficiente para ninfas de 1º ínstar em condições de laboratório, embora não tenha apresentado aumento do período residual como esperado. Em casa de vegetação, ninfas de 1º ínstar foram mais afetadas por duas das formulações, que diferenciaram do óleo de nim que causou maior controle. No teste com ninfas de 3º ínstar, não houve diferenciação de mortalidade entre as formulações. As nanoformulações foram menos eficientes para controlar ninfas de B. tabaci biótipo B do que o óleo de nim comercial.

  10. Surtos populacionais de Bemisia tabaci no estado de São Paulo Outbreaks of Bemisia tabaci in the São Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    André Luiz Lourenção

    1994-01-01

    Full Text Available A partir de 1991, tem sido observada a presença da mosca-branca Bemisia tabaci (Genn. (Homoptera: Aleyrodidae em altas populações em hortaliças e orna-mentais nos municípios paulistas de Paulínia, Holambra, Jaguariúna e Artur Nogueira. Foram constatadas infestações severas em tomateiro, brócolos, berinjela e aboboreira; nesta última, o sintoma observado em plantas infestadas pela mosca-branca é o prateamento da face superior das folhas, em conjunto com queda drástica da produção. Uma lavoura de tomate severamente infestada por B. tabaci apresentava o sintoma referido colo amadurecimento irregular dos frutos do tomateiro; plantas invasoras presentes nessa área também foram intensamente colonizadas, principalmente Sida rhombifolia L., Sonchus oleraceus L., Solanum viarum Dun. e Ipomoea acuminata Roem. & Schult. Em Holambra, verificaram-se ataques intensos em plantas ornamentais, principalmente crisântemo (Chrysantemum morifolium Ramat. e bico-de-papagaio (Euphorbia pulcherrima Willd.; roseiras foral pouco colonizadas. Nessas hortaliças e nas ornamentais, a aplicação quase diária de inseticidas não reduziu a infestação do inseto. Além dessas plantas, campos de algodão, em Holambra, e de feijão, em Paulínia, também foram infestados por B. tabaci. Nos E.U.A., a capacidade de certas populações de B. tabaci de induzir o prateamento da folha em aboboreira e de colonizar intensamente E. pulcherrima, entre outros fatores, têm levado à distinção do biótipo "B" ou "poinsétia", nome vulgar dessa euforbiácea; todavia, estudos recentes na Califórnia (E.U.A. mostram a possibilidade de se tratar de duas espécies distintas. Dada a similaridade entre as infestações associadas a B. tabaci que vêm ocorrendo naquele país e, mais recentemente, no Brasil, é provável que o biótipo B ou essa nova espécie tenha sido aqui introduzido.Since 1991, an increase in the populations of the whitefly Bemisia tabaci (Genn. (Homoptera

  11. Natural enemies managing the invasion of the Fig whitefly, Singhiella simplex (Hemiptera: Aleyrodidae), infesting a Ficus benjamina hedge

    Science.gov (United States)

    The fig whitefly, Singhiella simplex (Singh) is a recent invasive species that has become a major pest in Florida feeding on Ficus shrubs and trees. A pilot study was conducted on a weeping fig, Ficus benjamina shrub hedge to determine the efficacy and compatibility of a biopesticide (PFR 97™=Isaria...

  12. Tomato Yellow Leaf Curl Virus Benefits Population Growth of the Q Biotype of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Maluta, N K P; Garzo, E; Moreno, A; Lopes, J R S; Fereres, A

    2014-08-01

    Plant viruses can directly influence their insect vectors, and indirectly through their shared host plant, altering their behavior and performance in a mutualistic or rather antagonistic manner. One of the most studied begomovirus, Tomato yellow leaf curl virus (TYLCV), may also facilitate the expansion of its vector, the whitefly Bemisia tabaci (Gennadius). Considering the likely expansion of the disease and its major vector, we studied the direct and the indirect effects of a Mediterranean isolate of this virus (TYLCV-IL) on the biological performance of the Q biotype of B. tabaci. The following parameters were examined: development time and viability of nymphs, sex ratio, fecundity, and fertility and longevity. The results varied from positive to neutral depending on the parameter and the effect studied. TYLCV accelerated nymphal developmental and increased male longevity of B. tabaci when viruliferous insects developed on TYLCV-immune eggplants (direct effects). An indirect, positive effect of TYLCV-infected plants was observed on fecundity of B. tabaci, which laid more eggs on virus-infected than on noninfected tomato plants. Our results show that TYLCV enhances the population increase of its whitefly vector and that there is a high risk of rapid expansion of both the virus and its vector-the MED species of B. tabaci-into new areas when both agents interact together.

  13. Genome-Wide Characterization and Expression Profiling of Sugar Transporter Family in the Whitefly, Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Zezhong Yang

    2017-05-01

    Full Text Available Sugar transporters (STs play pivotal roles in the growth, development, and stress responses of phloem-sucking insects, such as the whitefly, Bemisia tabaci. In this study, 137 sugar transporters (STs were identified based on analysis of the genome and transcriptome of B. tabaci MEAM1. B. tabaci MEAM1 encodes a larger number of STs than other selected insects. Phylogenetic and molecular evolution analysis showed that the 137 STs formed three expanded clades and that the genes in Sternorrhyncha expanded clades had accelerated rates of evolution. B. tabaci sugar transporters (BTSTs were divided into three groups based on their expression profiles across developmental stages; however, no host-specific BTST was found in B. tabaci fed on different host plants. Feeding of B. tabaci adults with feeding diet containing dsRNA significantly reduced the transcript level of the target genes in B. tabaci and mortality was significantly improved in B. tabaci fed on dsRNA compared to the control, which indicates the sugar transporters may be used as potential RNAi targets for B. tabaci bio-control. These results provide a foundation for further studies of STs in B. tabaci.

  14. Plan de muestreo directo para Trialeurodes vaporariorum (Westwood (Hemiptera: Aleyrodidae en cultivos comerciales de tomate

    Directory of Open Access Journals (Sweden)

    Bernal Liliana

    2008-08-01

    Full Text Available

    Los daños ocasionados por Trialeurodes vaporariorum generan pérdidas económicas que disminuyen la producción y pueden contribuir en el alza de los precios del tomate. Para su control se acude a aplicaciones continuas de insecticidas, sin obtener resultados satisfactorios. Como alternativa de control se realizan liberaciones del parasitoide E. formosa. Sin embargo, el éxito de este sistema implica estimar la densidad de la plaga a través de un método de muestreo adecuado. Por ello, se estandarizó un plan de muestreo directo, económicamente viable, para ninfas de mosca blanca en un cultivo comercial de tomate bajo invernadero. Se determinó la incidencia de prácticas de manejo y de la fenología en la distribución espacial de ninfas. En términos generales, el muestreo se dividió en tres etapas: 1 muestreo totalmente aleatorio, entre las 5 y 7 semanas después de la siembra (sds, para plantas no divididas en tercios; 2 muestreo aleatorio, entre las 8 y 16 sds, los conteos se realizaron en hojas del tercio inferior; 3 muestreo bietápico: planta y hoja, entre las 17 y 24 sds, los conteos se efectuaron sobre hojas de los tercios medio y superior. Se encontró que prácticas culturales como el despunte influyeron en la distribución espacial de las ninfas. La implementación del muestreo directo generó un incremento en la producción del 0,06% y permitió estimar la densidad de ninfas de Trialeurodes vaporariorum en el cultivo (con precisiones de 5%, 10% y 25% como criterio para liberar E. formosa.

  15. Estudio de la resistencia a Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae en germoplasma cultivado y silvestre de tomate (Solanum lycopersicum L.

    Directory of Open Access Journals (Sweden)

    Yeimy García Valencia

    2013-12-01

    Full Text Available En la Universidad Nacional de Colombia sede Palmira, en condiciones de campo y casa de malla, se evaluaron por preferencia para oviposición y número de ninfas de mosca blanca (Bemisia tabaci (Gennadius varias accesiones silvestres y poblaciones segregantes de tomate resistentes al pasador del fruto, Neoleucinodes elegantalis (Guenée. Se utilizó un diseño de bloques completos al azar con cuatro repeticiones, donde se evaluaron como variables el número de huevos y de ninfas del insecto por hoja. En cada observación se incluyeron tres hojas del tercio superior, medio e inferior del tallo de la planta. Las poblaciones de mosca blanca fueron muy bajas en los dos primeros ciclos de cultivo (en campo debido, probablemente, a las altas precipitaciones. Estas condiciones no permitieron una selección de materiales resistentes o susceptibles a este insecto. En el tercer ciclo de cultivo, bajo condiciones de casa de malla, no se encontraron diferencias significativas entre los retrocruzamientos respecto al testigo susceptible para la variable preferencia por oviposición. El genotipo 4212P4 presentó el menor número de ninfas, mostrando que tiene posiblemente un mecanismo que le confiere menor atracción para B. tabaci. Se encontró que los genotipos menos preferidos para oviposición y con menor número de ninfas fueron PI 134417, PI 134418 y PI 126449 (Solanum habrochaites var. Glabratum S. Knapp y D. M Spooneer.

  16. Life history parameters of Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) at different environmental conditions on two bean cultivars

    NARCIS (Netherlands)

    Manzano, M.R.; Lenteren, van J.C.

    2009-01-01

    Life-history parameters of the greenhouse whitefly Trialeurodes vaporariorum (Westwood), an important pest of bean crops in Colombia, were determined in environmental control chambers on two dry bean (Phaseolus vulgaris) cultivars (cv.). Trialeurodes vaporariorum longevity on cv. Chocho decreased as

  17. Glutathione S-transferases are involved in thiamethoxam resistance in the field whitefly Bemisia tabaci Q (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Yang, Xin; He, Chao; Xie, Wen; Liu, Yating; Xia, Jixing; Yang, Zezong; Guo, Litao; Wen, Yanan; Wang, Shaoli; Wu, Qingjun; Yang, Fengshan; Zhou, Xiaomao; Zhang, Youjun

    2016-11-01

    The whitefly, Bemisia tabaci, has developed a high level of resistance to thiamethoxam, a second generation neonicotinoid insecticide that has been widely used to control this pest. In this study, we assessed the level of cross-resistance, the activities of detoxifying enzymes, and the expression profiles of 23 glutathione S-transferase (GST) genes in a thiamethoxam-resistant ant and -susceptible strain of Bemisia tabaci Q. The thiamethoxam-resistant strain showed a moderate level of cross-resistance to another nicotinoid insecticide imidacloprid, a low level of cross-resistance to acetamiprid and nitenpyram, and no significant cross-resistance to abamectin and bifenthrin. Among detoxifying enzymes, only GSTs had significantly higher activity in the resistant strain than in the susceptible strain. Seven of 23 GST genes were over-expressed in the resistant strain relative to the susceptible strain. Using the technology of RNA interference to knockdown a GST gene (GST14), the results showed that silencing GST14 increased the mortality of whiteflies to thiamethoxam in Bemisia tabaci. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Host-mediated effects of semipersistently transmitted Squash vein yellowing virus on sweetpotato whitefly (Hemiptera: Aleyrodidae) behavior and fitness

    Science.gov (United States)

    Alighting, settling and oviposition behavioral assays were conducted on Squash vein yellowing virus- (SqVYV-) infected and mock-inoculated squash and watermelon plants. Developmental time of immature stages, adult longevity, and fecundity were measured on SqVYV-infected and mock-inoculated squash p...

  19. Response of Bemisia tabaci Genn. (Hemiptera: Aleyrodidae) biotype B to genotypes of pepper Capsicum annuum (Solanales: Solanaceae).

    Science.gov (United States)

    Ballina-Gomez, H; Ruiz-Sanchez, E; Chan-Cupul, W; Latournerie-Moreno, L; Hernández-Alvarado, L; Islas-Flores, I; Zuñiga-Aguilar, J J

    2013-04-01

    Bemisia tabaci Genn. biotype B is a widely distributed plant pest that represents one of the major constraints for horticultural crop production. The purpose of the present work was to evaluate the oviposition preference, survivorship, and development of B. tabaci biotype B on semi-cultivated genotypes of Capsicum annuum from southeast Mexico. In free-choice experiments to evaluate the oviposition preference, lower number of eggs laid by B. tabaci biotype B was observed in the genotypes Maax and Xcat´ik relative to that in the commercial genotype Parado. Egg hatchability was significantly lower in Pico Paloma, Bolita, Blanco, Chawa, Payaso, and Xcat´ik than in the rest of the genotypes, including the commercial genotype Jalapeño. Likewise, survivorship of nymphs was significantly lower in Pico Paloma, Bolita, and Blanco than in the remaining genotypes. Nymph developmental time and the period of development from egg to adult were the shortest in Amaxito. Therefore, sources of resistance to B. tabaci biotype B by antibiosis (accumulation of plant defense compounds) might be found in the semi-cultivated genotypes Pico Paloma, Bolita, and Blanco.

  20. Susceptibility of Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae) to Imidacloprid, Thiamethoxam, Dinotefuran and Flupyradifurone in South Florida

    OpenAIRE

    Hugh A. Smith; Curtis A. Nagle; MacVean, Charles A.; Cindy L. McKenzie

    2016-01-01

    Populations of Bemisa tabaci MEAM1 were established from nineteen locations in south Florida, primarily from commercial tomato fields, and were tested using a cotton leaf petiole systemic uptake method for susceptibility to the nicotinic acetylcholine agonist insecticides imidacloprid, thiamethoxam, dinotefuran and flupyradifurone. Eleven populations produced LC50s for one or more chemicals that were not significantly different from the susceptible laboratory colony based on overlapping fiduc...

  1. Whitefly species (Hemiptera: Aleyrodidae on wild and cultivated plants in the horticultural region of Rosario, Santa Fe, Argentina

    Directory of Open Access Journals (Sweden)

    Gustavo G. GONSEBATT

    2012-01-01

    Full Text Available Las moscas blancas de importancia económica son polífagas y capaces de desarrollarse sobre numerosas plantas cultivadas y espontáneas. Registramos las especies de moscas blancas sobre cultivos hortícolas y de flores, y sobre las plantas silvestres asociadas. Observamos dos especies: Trialeurodes vaporariorum (Westwood y el complejo Bemisia tabaci (Gennadius. T. vaporariorum fue registrada sobre 24 especies de plantas (11 familias, 12 y 8 de las cuales son hospedantes nuevos para Argentina y a nivel mundial, respectivamente. El complejo B. tabaci fue registrado solo en sistemas de producción de flores, sobre 19 especies de plantas (11 familias, 14 y 7 de las cuales son nuevos hospedantes para Argentina y a nivel mundial, respectivamente. Los cultivos Glycine max (L. y Chrysanthemum morifolium Ramat., las especies silvestres Amaranthus blitum L., Amaranthus quitensis Kunth, Conyza bonariensis (L., Galinsoga parviflora Cav., Sonchus oleraceus L. y Wedelia glauca (Ortega O. Hoffm. ex Hicken fueron hospedantes de ambas especies. El único parasitoide registrado fue Eretmocerus californicus cercano a corni Haldeman (Hymenoptera: Aphelinidae sobre T. vaporariorum. Este estudio que constituye el primer relevamiento sistemático de plantas hospedantes en la región, aporta un mayor conocimiento sobre el rango de plantas hospedantes de las moscas blancas en Argentina.

  2. Phylogeographical structure in mitochondrial DNA of whitefly, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae) in southern India and Southeast Asia.

    Science.gov (United States)

    Ram Kumar, Nikhil; Chang, Jian-Cheng; Narayanan, Manikanda Boopathi; Ramasamy, Srinivasan

    2017-09-01

    South and Southeast Asia endure high vegetable production losses due to begomovirus diseases mainly transmitted by the insect vector, whitefly (Bemisia tabaci). Control over the spread of virus infection can be achieved through a better understanding of genetic diversity among B. tabaci. A total of 64 populations of B. tabaci collected from Tamil Nadu (India), Vietnam, Thailand, and Indonesia were investigated based on mitochondrial cytochrome c oxidase I (coxI) sequences. Populations from Tamil Nadu are distributed into three clades (Asia I, Asia II 7, and Asia II 8), whereas Indonesian populations settle along with Asia I population of India in the phylogenetic tree. Vietnam populations align with the Middle East-Asia Minor 1 (MEAM1) clade, and interestingly MEAM1 invades northern Vietnam quite recently. Samples from Thailand made a unique clade between the outgroup and the remaining B. tabaci, representing the possibility of a new subspecies. AMOVA analysis among populations from various districts in Tamil Nadu exhibits significant differences, which represent each district's individuality. This study proves that the use of coxI as a marker for molecular identification of B. tabaci can provide a better estimate of diversity. We provide important clues for developing insight into the genetic structure of B. tabaci, and suggest strategies for control.

  3. Effects of selected defoliants in combination with insecticides on sweetpotato whitefly (Hemiptera: Aleyrodidae) and its parasitoids in cotton

    Science.gov (United States)

    Effects of two defoliants, Def (S, S, Stributylphosphorotrithioate) and Dropp (thidiazuron) alone and in combination with two commonly used insecticides, a pyrethroid, Karate (lambda-cyhalothrin) and an organophosphate, Guthion (azinphosmethyl) on sweetpotato whitefly, Bemisia tabaci Gennadius Bioty...

  4. Begomovirus-Associated Satellite DNA Diversity Captured Through Vector-Enabled Metagenomic (VEM Surveys Using Whiteflies (Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Karyna Rosario

    2016-02-01

    Full Text Available Monopartite begomoviruses (Geminiviridae, which are whitefly-transmitted single-stranded DNA viruses known for causing devastating crop diseases, are often associated with satellite DNAs. Since begomovirus acquisition or exchange of satellite DNAs may lead to adaptation to new plant hosts and emergence of new disease complexes, it is important to investigate the diversity and distribution of these molecules. This study reports begomovirus-associated satellite DNAs identified during a vector-enabled metagenomic (VEM survey of begomoviruses using whiteflies collected in various locations (California (USA, Guatemala, Israel, Puerto Rico, and Spain. Protein-encoding satellite DNAs, including alphasatellites and betasatellites, were identified in Israel, Puerto Rico, and Guatemala. Novel alphasatellites were detected in samples from Guatemala and Puerto Rico, resulting in the description of a phylogenetic clade (DNA-3-type alphasatellites dominated by New World sequences. In addition, a diversity of small (~640–750 nucleotides satellite DNAs similar to satellites associated with begomoviruses infecting Ipomoea spp. were detected in Puerto Rico and Spain. A third class of satellite molecules, named gammasatellites, is proposed to encompass the increasing number of reported small (<1 kilobase, non-coding begomovirus-associated satellite DNAs. This VEM-based survey indicates that, although recently recovered begomovirus genomes are variations of known genetic themes, satellite DNAs hold unexplored genetic diversity.

  5. Susceptibility of Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae) to Imidacloprid, Thiamethoxam, Dinotefuran and Flupyradifurone in South Florida.

    Science.gov (United States)

    Smith, Hugh A; Nagle, Curtis A; MacVean, Charles A; McKenzie, Cindy L

    2016-10-20

    Populations of Bemisa tabaci MEAM1 were established from nineteen locations in south Florida, primarily from commercial tomato fields, and were tested using a cotton leaf petiole systemic uptake method for susceptibility to the nicotinic acetylcholine agonist insecticides imidacloprid, thiamethoxam, dinotefuran and flupyradifurone. Eleven populations produced LC 50 s for one or more chemicals that were not significantly different from the susceptible laboratory colony based on overlapping fiducial limits, indicating some degree of susceptibility. LC 50 s more than a 100-fold the laboratory colony were measured in at least one population for each material tested, indicating tolerance. LC 50 s (ppm) from field populations ranged from 0.901-24.952 for imidacloprid, 0.965-24.430 for thiamethoxam, 0.043-3.350 for dinotefuran and 0.011-1.471 for flupyradifurone. Based on overlapping fiducial limits, there were no significant differences in relative mean potency estimates for flupyradifurone and dinotefuran in relation to imidacloprid and thiamethoxam.

  6. Extratos aquosos de Leucaena leucocephala e Sterculia foetida no controle de Bemisia tabaci biótipo B (Hemiptera: Aleyrodidae

    Directory of Open Access Journals (Sweden)

    Vasconcelos Geraldo José Nascimento de

    2006-01-01

    Full Text Available A presente pesquisa foi desenvolvida na Cidade de Recife-PE, com o objetivo de avaliar a ação inseticida, insetistática e repelente de extratos aquosos de duas essências florestais sobre ovos, ninfas e adultos de Bemisia tabaci biótipo B (Genn., 1889 criados em Brassica oleracea var. acephala L. Os extratos utilizados foram de Leucaena leucocephala (Lam. De Wit. e Sterculia foetida L. Sementes e folhas das duas espécies foram coletadas, secadas e trituradas. Em seguida, os extratos foram preparados na proporção de 5g de cada parte vegetal/50mL de água. Folhas de B. oleracea var. acephala foram imersas durante 30seg nos extratos e, em seguida, os insetos foram confinados na folha tratada. Os extratos de sementes de L. leucocephala e de folhas de S. foetida provocaram mortalidade de 60 e 41% sobre ovos de B. tabaci, respectivamente. Na fase ninfal, o tratamento com folhas de S. foetida apresentou o melhor resultado, com 74,6% de mortalidade. Nenhum dos extratos testados apresentou supressão para oviposição na espécie estudada. Os indivíduos tratados com os extratos de L. leucocephala tiveram menor longevidade e maior oviposição com relação aos tratamentos com S. foetida e com a testemunha. O uso de extratos aquosos de sementes de L. leucocephala e de folhas de S. foetida mostra-se promissor para o controle alternativo de B. tabaci.

  7. Adult survival of Delphastus catalinae (Coleoptera: Coccinellidae), a predator of whiteflies (Hemiptera: Aleyrodidae), on diets of whiteflies, honeydew and honey

    Science.gov (United States)

    Delphastus catalinae (Horn) (Coleoptera: Coccinellidae) is a predator that is commercially sold for the management of whiteflies. A study was conducted to assay the effect of selected diets on the survival of adult D. catlinae. Treatments of water (as a control), 10% honey, honeydew, and whiteflie...

  8. Direct and indirect impacts of infestation of tomato plant by Myzus persicae (Hemiptera: Aphididae) on Bemisia tabaci (Hemiptera: Aleyrodidae).

    Science.gov (United States)

    Tan, Xiao-Ling; Wang, Su; Ridsdill-Smith, James; Liu, Tong-Xian

    2014-01-01

    The impacts of infestation by the green peach aphid (Myzus persicae) on sweetpotato whitefly (Bemisia tabaci) settling on tomato were determined in seven separate experiments with whole plants and with detached leaves through manipulation of four factors: durations of aphid infestation, density of aphids, intervals between aphid removal after different durations of infestation and the time of whitefly release, and leaf positions on the plants. The results demonstrated that B. tabaci preferred to settle on the plant leaves that had not been infested by aphids when they had a choice. The plant leaves on which aphids were still present (direct effect) had fewer whiteflies than those previously infested by aphids (indirect effect). The whiteflies were able to settle on the plant which aphids had previously infested, and also could settle on leaves with aphids if no uninfested plants were available. Tests of direct factors revealed that duration of aphid infestation had a stronger effect on whitefly landing preference than aphid density; whitefly preference was the least when 20 aphids fed on the leaves for 72 h. Tests of indirect effects revealed that the major factor that affected whitefly preference for a host plant was the interval between the time of aphid removal after infestation and the time of whitefly release. The importance of the four factors that affected the induced plant defense against whiteflies can be arranged in the following order: time intervals between aphid removal and whitefly release > durations of aphid infestation > density of aphids > leaf positions on the plants. In conclusion, the density of aphid infestation and time for which they were feeding influenced the production of induced compounds by tomatoes, the whitefly responses to the plants, and reduced interspecific competition.

  9. Aqueous extracts of Leucaena leucocephala and Sterculia foetida to the control of Bemisia tabaci biotype B (Hemiptera: Aleyrodidae)

    OpenAIRE

    Vasconcelos Geraldo José Nascimento de; Gondim Júnior Manoel Guedes Corrêa; Barros Reginaldo

    2006-01-01

    A presente pesquisa foi desenvolvida na Cidade de Recife-PE, com o objetivo de avaliar a ação inseticida, insetistática e repelente de extratos aquosos de duas essências florestais sobre ovos, ninfas e adultos de Bemisia tabaci biótipo B (Genn., 1889) criados em Brassica oleracea var. acephala L. Os extratos utilizados foram de Leucaena leucocephala (Lam.) De Wit. e Sterculia foetida L. Sementes e folhas das duas espécies foram coletadas, secadas e trituradas. Em seguida, os extratos foram pr...

  10. Occurrence of Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae parasitizing Bemisia tabaci (Genn. biotype B (Hemiptera: Aleyrodidae in Brazil

    Directory of Open Access Journals (Sweden)

    André Luiz Lourenção

    2014-06-01

    Full Text Available The parasitism of Bemisia tabaci (Genn. biotype B nymphs on cotton plants was observed during a research on resistance of cotton genotypes to this whitefly. The experiment was set in a greenhouse at the Experimental Station of the Instituto Agronômico (IAC, in Campinas, São Paulo State, Brazil. Samples of the parasitized nymphs were collected and maintained in laboratory to monitor the parasitism and obtain the adult parasitoids. A total of 129 adult parasitoids were obtained, including one Encarsia inaron (Walker, 13 En. lutea (Masi, and 115 Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae. This is the first report of Er. mundus in Brazil.

  11. A new species of Encarsia (Hymenoptera, Aphelinidae) developing on ficus whitefly Singhiella simplex (Hemiptera, Aleyrodidae) in China and Taiwan

    OpenAIRE

    Ko, Chiun Cheng; Shih, Yuan Tung; Schmidt, Stefan; Polaszek, Andrew

    2015-01-01

    Encarsia singhiellae Polaszek & Shih, sp. n., is described and illustrated. It is known so far from Taiwanand China. All specimens were reared from the ficus, or fig, whitefly Singhiella simplex (Singh), an Asian species recently attaining pest status in California, Colombia, and Florida.

  12. High Level of Nitrogen Makes Tomato Plants Releasing Less Volatiles and Attracting More Bemisia tabaci (Hemiptera: Aleyrodidae)

    Science.gov (United States)

    Islam, Md. Nazrul; Hasanuzzaman, Abu Tayeb Mohammad; Zhang, Zhan-Feng; Zhang, Yi; Liu, Tong-Xian

    2017-01-01

    Tomato (Solanum lycopersicum) production is seriously hampered by the infestation of the sweetpotato whitefly, Bemisia tabaci MEAM 1 (Middle East-Asia Minor 1). The infestation behavior of the whiteflies could be affected by the quantity of plant released volatile organic compounds (VOCs) related to nitrogen concentrations of the plant. In this study, we determined the infestation behavior of B. tabaci to the tomato plants that produced different levels of VOCs after application of different levels of nitrogen with a wind tunnel and an olfactometer. We also analyzed the VOCs released from nitrogen-treated tomato plants using solid phase microextraction and gas chromatography-mass spectrometry. The results revealed that the production of eight VOCs (β-pinene, (+)-4-carene, α-terpinene, p-cymene, β-phellandrene, α-copaene, β-caryophyllene, and α-humulene) was reduced after the plants were treated with high levels of nitrogen. However, more whiteflies were attracted to the tomato plants treated with high levels of nitrogen than to the plants treated with normal or below normal levels of nitrogen. These results clearly indicated that nitrogen can change the quality and quantity of tomato plant volatile chemicals, which play important roles in B. tabaci host plant selection. PMID:28408917

  13. Susceptibility of Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae to Imidacloprid, Thiamethoxam, Dinotefuran and Flupyradifurone in South Florida

    Directory of Open Access Journals (Sweden)

    Hugh A. Smith

    2016-10-01

    Full Text Available Populations of Bemisa tabaci MEAM1 were established from nineteen locations in south Florida, primarily from commercial tomato fields, and were tested using a cotton leaf petiole systemic uptake method for susceptibility to the nicotinic acetylcholine agonist insecticides imidacloprid, thiamethoxam, dinotefuran and flupyradifurone. Eleven populations produced LC50s for one or more chemicals that were not significantly different from the susceptible laboratory colony based on overlapping fiducial limits, indicating some degree of susceptibility. LC50s more than a 100-fold the laboratory colony were measured in at least one population for each material tested, indicating tolerance. LC50s (ppm from field populations ranged from 0.901–24.952 for imidacloprid, 0.965–24.430 for thiamethoxam, 0.043–3.350 for dinotefuran and 0.011–1.471 for flupyradifurone. Based on overlapping fiducial limits, there were no significant differences in relative mean potency estimates for flupyradifurone and dinotefuran in relation to imidacloprid and thiamethoxam.

  14. [Biology and non-preference for oviposition by Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) on cotton cultivars].

    Science.gov (United States)

    Torres, Lucas C; Souza, Brígida; Amaral, Bruno B; Tanque, Ricardo L

    2007-01-01

    The purposes of this work were to evaluate some biological aspects of Bemisia tabaci (Gennadius) biotype B at egg and nymphal stages and to evaluate the non-preference for oviposition and its correlation with the number and type of trichomes on the cotton cultivars BRS Ipê, BRS 186-Precoce 3, BRS Acala, BRS Verde, BRS-200 Marrom, BRS Cedro, BRS Ita 90-2 and BRS Aroeira. The experiments were conducted in climatic chambers at 28 +/- 2 degrees C, 70% RH and photophase of 14h, and in greenhouse. Egg fertility was not affected by the cotton cultivars but survival in egg-adult period was influenced by the host plant. There was no influence of cultivars neither on the duration of egg stage, nymphs at 2nd, 3rd and 4th instars nor on the duration from egg to adult, but nymphs reared on the cultivar BRS Ipê had their 1st instar extended. Low number of eggs was detected on the cultivars BRS Aroeira, BRS Verde and BRS Ita 90-2 in both experiments with and without oviposition choice, indicating a possible mechanism of resistance, but no correlation could be established between trichome densisty and oviposition non-preference.

  15. Refined Global Analysis of Bemisia tabaci (Hemiptera: Sternorrhyncha: Aleyrodoidea: Aleyrodidae) Mitochondrial Cytochrome Oxidase 1 to Identify Species Level Genetic Boundaries

    National Research Council Canada - National Science Library

    A. Dinsdale; L. Cook; C. Riginos; Y. M. Buckley; P. De Barro

    2010-01-01

    ..., the approaches used to apply them and in our understanding of what genetic structure within B. tabaci means. Our response has been to use mitochondrial gene cytochrome oxidase one to consider how to clearly and consistently define genetic separation...

  16. Inundative Field Releases and Evaluation of Three Predators for Bemisia tabasi (Hemiptera: Aleyrodidae) Management in Three Vegetable Crops

    Science.gov (United States)

    The sweetpotato whitefly, Bemisia tabaci (Gennadius), is a global pest on numerous crops, including vegetables. Weekly inundative releases of a coccinellid predator (Coccinella undecimpunctata L.), a mirid predator [Macrophillus caliginosus (Wagner)] and a neuropteran predator [Chrysoperla carnea S...

  17. Vector-Enabled Metagenomic (VEM Surveys Using Whiteflies (Aleyrodidae Reveal Novel Begomovirus Species in the New and OldWorlds

    Directory of Open Access Journals (Sweden)

    Karyna Rosario

    2015-10-01

    Full Text Available Whitefly-transmitted viruses belonging to the genus Begomovirus (family Geminiviridae represent a substantial threat to agricultural food production. The rapid evolutionary potential of these single-stranded DNA viruses combined with the polyphagous feeding behavior of their whitefly vector (Bemisia tabaci can lead to the emergence of damaging viral strains. Therefore, it is crucial to characterize begomoviruses circulating in different regions and crops globally. This study utilized vector-enabled metagenomics (VEM coupled with high-throughput sequencing to survey begomoviruses directly from whiteflies collected in various locations (California (USA, Guatemala, Israel, Puerto Rico, and Spain. Begomoviruses were detected in all locations, with the highest diversity identified in Guatemala where up to seven different species were identified in a single field. Both bipartite and monopartite viruses were detected, including seven new begomovirus species from Guatemala, Puerto Rico, and Spain. This begomovirus survey extends the known diversity of these highly damaging plant viruses. However, the new genomes described here and in the recent literature appear to reflect the outcome of interactions between closely-related species, often resulting from recombination, instead of unique, highly divergent species.

  18. Susceptibility of Bemisia tabaci MEAM1 (Hemiptera: Aleyrodidae) to imidacloprid, thiamethoxam, dinotefuran and flupyradifurone in south Florida

    Science.gov (United States)

    Populations of Bemisa tabaci Middle East Asia Minor 1 (MEAM 1) were established from nineteen locations in south Florida, primarily from commercial tomato fields, and were tested using a cotton leaf petiole systemic uptake method for susceptibility to the nicotinic acetylcholine agonist insecticides...

  19. Baseline Susceptibilities of B- and Q-biotype Bemisia tabaci to anthranilic diamides

    Science.gov (United States)

    Development of pyriproxyfen and neonicotinoid resistance in the B biotype whitefly and recent introduction of the Q biotype are threatening the current whitefly management programs in Arizona. Whether the novel anthranilic diamides chlorantraniliprole and cyantraniliprole can be integrated into the ...

  20. Baseline susceptibilities of B- and Q-biotype Bemisia tabaci to anthranilic diamides in Arizona.

    Science.gov (United States)

    Li, Xianchun; Degain, Benjamin A; Harpold, Virginia S; Marçon, Paula G; Nichols, Robert L; Fournier, Alfred J; Naranjo, Steven E; Palumbo, John C; Ellsworth, Peter C

    2012-01-01

    Development of pyriproxyfen and neonicotinoid resistance in the B-biotype whitefly and recent introduction of the Q biotype have the potential to threaten current whitefly management programs in Arizona. The possibility of integrating the novel anthranilic diamides chlorantraniliprole and cyantraniliprole into the current program to tackle these threats largely depends on whether these compounds have cross-resistance with pyriproxyfen and neonicotinoids in whiteflies. To address this question, the authors bioassayed a susceptible B-biotype strain, a pyriproxyfen-resistant B-biotype strain, four multiply resistant Q-biotype strains and 16 B-biotype field populations from Arizona with a systemic uptake bioassay developed in the present study. The magnitude of variations in LC(50) and LC(99) among the B-biotype populations or the Q-biotype strains was less than fivefold and tenfold, respectively, for both chlorantraniliprole and cyantraniliprole. The Q-biotype strains were relatively more tolerant than the B-biotype populations. No correlations were observed between the LC(50) (or LC(99)) values of the two diamides against the B- and Q-biotype populations tested and their survival rates at a discriminating dose of pyriproxyfen or imidacloprid. These results indicate the absence of cross-resistance between the two anthranilic diamides and the currently used neonicotinoids and pyriproxyfen. Future variation in susceptibility of field populations to chlorantraniliprole and cyantraniliprole could be documented according to the baseline susceptibility range of the populations tested in this study. Copyright © 2011 Society of Chemical Industry.

  1. Reproducción de cochinilla silvestre Dactylopius opuntiae (Homóptera: Dactylopiidae Reproduction of wild cochineal Dactylopius opuntiae (Homoptera: Dactylopiidae

    Directory of Open Access Journals (Sweden)

    Arnoldo Flores-Hernández

    2006-06-01

    Full Text Available Por sus características, la cochinilla silvestre ofrece perspectivas de aprovechamiento como fuente de carmín y para el mejoramiento genético de la grana fina. Por lo anterior, se estableció una multiplicación y crianza de cochinilla silvestre, proveniente de la zona árida del norte de México para caracterizarla, utilizando como hospedero a Opuntia megacantha Salm Dyck. Los resultados indican que la especie silvestre pertenece al género-especie Dactylopius opuntia. Se determinó la presencia de partenogénesis en hembras. La duración de los estadios biológicos depende del sexo del insecto; el adulto hembra permaneció durante 38.4 días y 4.2 días para machos, los primeros estadios ninfales fueron similares en duración (18.1-19.8 días. El ciclo biológico de las hembras fue de 77 días mientras que el de los machos fue de 43 días. Para las hembras se estimó un periodo de preoviposición de 18.8 días, manteniéndose en oviposición durante 21 días con un promedio de 131 insectos por hembra. La proporción sexual hembras: machos fue 1:1. El tipo de reproducción fue predominantemente sexual, aunque hubo hembras partenogénicas. Este es el primer reporte de Dactylopius opuntiae como cochinilla silvestre asociada a la zona árida del noreste de México, específicamente en el Bolsón de Mapimí, Durango, México.Wild cochineal has characteristics that offer advantage as a source of carmine and for fine cochineal improvement. To characterize wild cochineal, we initiated a breeding effort raising wild cochineal from the arid zone of the north oh Mexico, using as a host organism Opuntia megacantha Salm dick. The results indicate that the wild specie is Dactylopius opuntiae. The presence of parthenogenesis in females was determined. The duration of ontogenetic stages depends on the sex of the insect. The adult female lasted 38.4 days and 4.2 days for males, the first stage nymphs were similar in duration (18-19.8 days. The complete biological cycle of the females was 77 days, and in the males 43 days. A period of preoviposition of 18.8 days for the females was found, laying eggs during 21 days with an average of 131 insects per female. The sex ratio female: male was 1:1. The reproduction generally was sexual although there were parthenogenetic females. This is the first report of Dactylopius opuntiae as a source of wild cochineal in the arid zone of North, Central and Norwest of Mexico specifically in the Bolson of Mapimí, Durango, Mexico.

  2. The jacoona assemblage of the genus Dundubia Amyot & Serville (Homoptera: Cicadidae): a taxonomic study of its species and a discussion of its phylogenetic relationships

    NARCIS (Netherlands)

    Beuk, Paul L.Th.

    1996-01-01

    The species of Orientopsaltria with unicolorous opercula and three related species of Platylomia are transferred to the genus Dundubia and allocated in the ‘Dundubia jacoona assemblage’ pending further investigation. The assemblage comprises eleven species in total; all are found in the

  3. Biomarker discovery from the top down: protein biomarkers for efficient virus transmission by insects (Homoptera: Aphididae) discovered by coupling genetics and 2-D DIGE

    Science.gov (United States)

    Yellow dwarf viruses cause the most economically important virus diseases of cereal crops worldwide and are vectored by aphids. The identification of vector proteins mediating virus transmission is critical to develop sustainable virus management practices and to understand viral strategies for cir...

  4. Spring migration of damson-hop aphid,Phorodon humuli (Homoptera, Aphididae), and summer host plant-derived semiochemicals released on feeding.

    Science.gov (United States)

    Campbell, C A; Pettersson, J; Pickett, J A; Wadhams, L J; Woodcock, C M

    1993-07-01

    Behavioral studies using an olfactometer demonstrated that spring migrants of the damson-hop aphid,Phorodon humuli, respond to semiochemicals released by spring migrants feeding on hop leaves. Samples of the total volatiles released on feeding were analyzed by coupled gas chromatographysingle cell recording techniques and showed the presence of several active components. Three compounds were identified, using coupled gas chromatography-mass spectrometry, as methyl salicylate, (E)-2-hexenal andβ-caryophyllene. These three compounds elicited responses from separate olfactory receptors on the antenna. In the olfactometer, both (E)-2-hexenal andβ-caryophyllene gave positive responses from spring migrants, and a mixture of the two compounds in the natural ratio was more attractive than (E)-2-hexenal alone. Addition of methyl salicylate eliminated the response to the active binary mixture.

  5. A reliable bioassay procedure to evaluate per os toxicity of Bacillus thuringiensis strains against the rice delphacid, Tagosodes orizicolus (Homoptera: Delphacidae)

    OpenAIRE

    Mora, Rebeca; E. Ibarra, Jorge; M. Espinoza, Ana

    2006-01-01

    A reliable bioassay procedure was developed to test ingested Bacillus thuringiensis (Bt) toxins on the rice delphacid Tagosodes orizicolus. Initially, several colonies were established under greenhouse conditions, using rice plants to nurture the insect. For the bioassay, an in vitro feeding system was developed for third to fourth instar nymphs. Insects were fed through Parafilm membranes on sugar (10 % sucrose) and honey bee (1:48 vol/vol) solutions, observing a natural mortality of 10-15 %...

  6. A reliable bioassay procedure to evaluate per os toxicity of Bacillus thuringiensis strains against the rice delphacid, Tagosodes orizicolus (Homoptera: Delphacidae).

    Science.gov (United States)

    Mora, Rebeca; Ibarra, Jorge E; Espinoza, Ana M

    2007-06-01

    A reliable bioassay procedure was developed to test ingested Bacillus thuringiensis (Bt) toxins on the rice delphacid Tagosodes orizicolus. Initially, several colonies were established under greenhouse conditions, using rice plants to nurture the insect. For the bioassay, an in vitro feeding system was developed for third to fourth instar nymphs. Insects were fed through Parafilm membranes on sugar (10 % sucrose) and honey bee (1:48 vol/vol) solutions, observing a natural mortality of 10-15 % and 0-5 %, respectively. Results were reproducible under controlled conditions during the assay (18+/-0.1 degrees C at night and 28+/-0.1 degrees C during the day, 80 % RH and a 12:12 day:light photoperiod). In addition, natural mortality was quantified on insect colonies, collected from three different geographic areas of Costa Rica, with no significant differences between colonies under controlled conditions. Finally, bioassays were performed to evaluate the toxicity of a Bt collection on T. orizicolus. A preliminary sample of twenty-seven Bt strains was evaluated on coarse bioassays using three loops of sporulated colonies in 9 ml of liquid diet, the strains that exhibited higher percentages of T. orizicolus mortality were further analyzed in bioassays using lyophilized spores and crystals (1 mg/ml). As a result, strains 26-O-to, 40-X-m, 43-S-d and 23-O-to isolated from homopteran insects showed mortalities of 74, 96, 44 and 82% respectively while HD-137, HD-1 and Bti showed 19, 83 and 95% mortalities. Controls showed mortalities between 0 and 10% in all bioassays. This is the first report of a reliable bioassay procedure to evaluate per os toxicity for a homopteran species using Bacillus thuringiensis strains.

  7. The propensity of different larval stages of lacewing Chrysoperla carnea (Stephens (Neuroptera: Chrysopidae to control aphid Myzus persicae (Sulzer (Homoptera: Aphididae evaluated on Canola Brassica napus L.

    Directory of Open Access Journals (Sweden)

    Muhammad Sarwar

    2014-04-01

    Full Text Available Green lacewings (Neuroptera: Chrysopidae are considered among the most effective generalist predators of aphids. In the present experimentation, the use of 1st, 2nd and 3rd instars of the chrysopid Chrysoperla carnea (Stephens larvae against aphids pest was investigated under field conditions in Brassica napus L. Four releases of predator’s 1st, 2nd and 3rd instar larvae were made from the time of aphid’s appearance on canola crop till its maturity at fortnightly intervals. The influences on aphids due to the larvae of C. carnea predator were assessed by examining pest incidence and abundance of the natural enemies at plant growth stage, and seed yield recorded at crop harvest in the test field. Results indicated that predators, irrespective of their developmental stage, reacted very positively to their preys’ reduction except in untreated control. Of the different larval stages tested, the applications of 1st instar followed by 2nd and 3rd instar larvae were most effective in reducing aphids’ population compared with untreated control. In the similar fashion, the releases of 1st and 2nd instar larvae of C. carnea were more effective in increasing crop yields compared with check treatment. Obviously, the applications of 1st and 2nd instar larvae of C. carnea involved efficiently in prey location and consumption, and performed predation activity for longer period (2-3 weeks. On the other hand, the release of 3rd instar larvae was too late to play a direct beneficial role in crop protection suggesting that they may have less time (1 week to remain involved in efficient prey consumption. Further, 1st or 2nd instar larvae may be much hungrier and eaten more pests in study areas without resting or moving to new location and thus can potentially be used to enhance biological control of aphids.

  8. Insecticidal activities of their components derived from the essential oils of Cinnamomum sp. barks and against Ricania sp. (Homoptera: Ricaniidae), a newly recorded pest.

    Science.gov (United States)

    Jeon, Ye-Jin; Lee, Sang-Guei; Yang, Young-Cheol; Lee, Hoi-Seon

    2017-10-01

    Insecticidal activities of Cinnamomum cassia and Cinnamomum zeylanicum oils and their components are not known against Ricania sp. Insecticidal activities of major components derived from C. cassia and C. zeylanicum oils were examined in spray and leaf-dipping bioassays against Ricania sp. nymphs and adults. The LC 50 value of C. cassia and C. zeylanicum oils was 37.66 and 72.62 mg L -1 , respectively, in leaf-dipping bioassays against Ricania sp. nymphs, and 77.38 and 134.86 mg L -1 in spray bioassays against Ricania sp. adults. The insecticidal activity of C. cassia oil was 1.74-1.93 times greater than that of C. zeylanicum oil. When examined by gas chromatography mass spectrometry, the cinnamaldehyde content of C. cassia and C. zeylanicum oils was 80.20% and 46.32%, respectively. Based on the LC 50 values of cinnamaldehyde, hydrocinnamaldehyde and 4-hydroxy-3-methoxycinnamaldehyde against Ricania sp. nymphs and adults, cinnamaldehyde (LC 50 , 31.25 and 62.43 mg L -1 ) demonstrated the most potent insecticidal activity, followed by 4-hydroxy-3-methoxycinnamaldehyde (172.19 and 212.77 mg L -1 ) and hydrocinnamaldehyde (275.05 and 318.63 mg L -1 ). The findings revealed that C. cassia oil, C. zeylanicum oil and cinnamaldehyde have potential value in the management of Ricania sp. and could be valuable as effective insecticides. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  9. Cacopsylla picta (costalis Flor, 1861 (Förster, 1848 (Homoptera, Psyllidae a New Jumping Plant Louse Species on Apples in Serbia

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    Dušanka Jerinić-Prodanović

    2007-01-01

    Full Text Available Until recently only one jumping plant louse species Cacopsylla mali Schm. has been described on apples in domestic literature. Over the past few years investigations of Psylloidea on apples in Serbia have proved incidences of another two species, namely C. melanoneuraFörster and C. picta (costalis Förster. The aim was to describe the basic morphological characteristics of the newly identified jumping plant louse C. picta on apples in Serbia, its distribution and development cycle.

  10. Microsatellite markers reveal a predominant sugarcane aphid (Homoptera: Aphididae) clone is found on sorghum in seven states and one territory of the USA

    Science.gov (United States)

    The sugarcane aphid, Melanaphis sacchari, has become a serious pest causing severe economic losses to sorghum grown in the southern United States (U.S.). Since its original detection in four states in 2013, M. sacchari on sorghum has now, for 2016, spread to 19 states. The presence of one or multip...

  11. Ecological studies on the greedy scale, Hemiberlisia rapax (Comstock) (Homoptera: Diaspididae) on pear trees in burg El-Arab area, Alexandria, Egypt.

    Science.gov (United States)

    Mesbah, H A; Moursi Khadiga, S; Mourad, A K; Abdel-Razak Soad, I

    2008-01-01

    The greedy scale, Hemiberlisia rapax (Comstock) causes economic damage on pear trees under irrigation system in Burg El-Arab area (50 Km. West of Alexandria). The infestation rate of H. rapax reached its first maximum rate during August to October, and the second one occurred from January to March. The 1st highest peak of insect population occurred during September and October; the second was during January and February, and the third one corresponded to April for the 1st and the 2nd successive seasons. The statistical analysis was performed to determine the relationship among the weather factors of mean daily temperature, daily relative humidity, wind speed, and dew point in relation to the population activity of Hemiberlisia rapax. The immature stages had two peaks of fluctuation during October to November and July to August. The adult females reached their maximum rates during winter and spring months. Adult males appeared in late March in few numbers. The insect was parasitized by Aphytis diaspidis (Howard) (Hymenoptera: Aphelinidae) in maximum numbers in June and July. This parasitoid had three overlapping generations all the year round. The first in September-October; the second extended from March to May; while the third one lasted from July to September.

  12. Scymnus (Pullus) suturalis Thunberg (Coleoptera: Coccinellidae): New locality records and a report on feeding on hemlock woolly adelgid, Adelges tsugae Annand (Homoptera: Adelgidae)

    Science.gov (United States)

    S.M. Lyon; M.E. Montgomery

    1995-01-01

    Scymnus (Pullus) suturalis Thunberg is a Palearctic species that occurs on conifers, where it is reported to feed on aphids (I. Hodek. 1973. Biology of Coccinellidae. Academia, Czechoslovak Academy of Science. Prague). The occurrence of S. suturalis in North America was first reported by R.D. Gordon (1982. Proc. Entomol. Soc. Wash...

  13. Effect of temperature on life history and population growth parameters of Planococcus citri (Homoptera, Pseudococcidae on coleus [Solenostemon scutellarioides (L. Codd.

    Directory of Open Access Journals (Sweden)

    Goldasteh Shila

    2009-01-01

    Full Text Available The development, life history, reproduction, and population growth parameters of Planococcus citri Risso on coleus [Solenostemon scutellarioides (L. Codd.] were studied at various temperatures ranging from 10 to 37ºC, 70±10% RH, and photoperiod length of 16: 8 h (L: D. Females and males successfully developed into adults at from 15 to 32ºC and 18 to 32ºC, respectively. All first instars died at 10, 12, and 37ºC. Lower temperatures (10, 12, and 15ºC caused higher egg mortality than did higher temperatures (32, 35, and 37ºC. At all temperatures (except 15ºC, the highest percentage of nymphal mortality was observed in the first instar. The sex ratio was female-biased between 15 and 30ºC, but there was a slightly higher number of males at 32ºC. The highest adult longevities of females and males were obtained at 18 and 25°C, respectively. The pre-oviposition, oviposition, and post-oviposition periods were significantly different at various temperatures. The highest fecundity was observed at 23ºC. The shortest and longest oviposition periods occurred at 32 and 18ºC, respectively. Maximum values of the intrinsic rate of natural increase (rm, net reproduction rate (R0, and finite rate of increase (λ and the shortest mean generation time (T and doubling time (DT were obtained at 25ºC. Our findings showed citrus mealybug performances to be highly affected by temperature.

  14. Female-induced increase of host-plant volatiles enhance specific attraction of aphid male Dysaphis plantaginea (Homoptera: Aphididae) to the sex pheromone

    NARCIS (Netherlands)

    Tol, van R.W.H.M.; Helsen, H.H.M.; Griepink, F.C.; Kogel, de W.J.

    2009-01-01

    All aphid species studied so far share the same sex pheromone components, nepetalactol and nepetalactone. Variation by different enantiomers and blends of the two components released by different aphid species are limited and can only partially explain species-specific attraction of males to

  15. Host Plant-Herbivore-Predator Interactions in Chrysoperla carnea (Neuroptera: Chrysopidae) and Myzus persicae (Homoptera: Aphididae) on Four Plant Species Under Laboratory Conditions.

    Science.gov (United States)

    Farrokhi, Milad; Gharekhani, Gholamhossein; Iranipour, Shahzad; Hassanpour, Mahdi

    2017-12-05

    The common green lacewing, Chrysoperla carnea (Stephens) (Neuroptera: Chrysopidae), is a well-known biocontrol agent. The current study examined host plant-herbivore-predator interactions with C. carnea and Myzus persicae on four host plants (peach, almond, pepper, and potato). The experiments were carried out at 25 ± 1°C and 65 ± 5% RH at a photoperiod of 16:8 (L:D) h). Duration of the preadult growth period, adult longevity, fecundity, and population growth parameters were analyzed based on the age-stage, two-sex life table theory. The shortest and longest preadult developmental times of the predator were observed on the peach and potato, respectively. The highest and lowest predation rate, oviposition period, and male and female longevity of predator were also observed on the peach and potato, respectively. The lowest intrinsic rate of increase (r) and finite rate of increase (λ) were observed on the potato (0.1087 and 1.11 d-1, respectively) and the highest on the peach (0.1460 and 1.15 d-1, respectively). The maximum and minimum mean generation times (T) were 41.84 and 35.59 d in the potato and peach, respectively. Overall, peach was found to be a more appropriate host than the other host plants for development and predation fitness of C. carnea. These findings reveal that information on tritrophic interactions and subsequent life table evaluation of natural enemies improves integrated pest management programs. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by (a) US Government employee(s) and is in the public domain in the US.

  16. Reproducción de cochinilla silvestre Dactylopius opuntiae (Homóptera: Dactylopiidae) Reproduction of wild cochineal Dactylopius opuntiae (Homoptera: Dactylopiidae)

    OpenAIRE

    Arnoldo Flores-Hernández; Bernardo Murillo-Amador; Edgar Omar Rueda-Puente; José Cruz Salazar-Torres; José Luis García-Hernández; Enrique Troyo-Diéguez

    2006-01-01

    Por sus características, la cochinilla silvestre ofrece perspectivas de aprovechamiento como fuente de carmín y para el mejoramiento genético de la grana fina. Por lo anterior, se estableció una multiplicación y crianza de cochinilla silvestre, proveniente de la zona árida del norte de México para caracterizarla, utilizando como hospedero a Opuntia megacantha Salm Dyck. Los resultados indican que la especie silvestre pertenece al género-especie Dactylopius opuntia. Se determinó la presencia d...

  17. Dinámica poblacional de cicadélidos (Homoptera: Cicadellidae en un agroecosistema cañero de Cuba

    Directory of Open Access Journals (Sweden)

    Marta M. Hidalgo-Gato

    1999-09-01

    Full Text Available Un agroecosistema cañero en San Pedro, Ciudad de La Habana, Cuba, arrojó una riqueza de cicadélidos de 23 especies, con dos nuevos registros para el cultivo: Balclutha rufofasciata (Merino y Tylocygus geometricus (Signoret. Se realizaron recolectas mensuales durante los años 1991 a 1994, para lo cual se empleó una red entomológica. En el estudio de la dinámica poblacional de las especies más abundantes y frecuentes se destacaron B. guajanae (De Long con una densidad de 1 920 ind/ha en el cultivo de la caña y Hortensia similis Walk con 18 960 ind/ha en la vegetación segetal. Esta última está integrada fundamentalmente por Rottboellia cocninchinensis (Lourd. Clayton, Echinochloa colona (L. Link, Chamaesyce hyssopifolia (L. Small y Euphorbia heterophylla L. El cultivo de la caña de azúcar presentó mayor organización espacial, diversidad (0.61 y equitatividad (0.25, mientras que la vegetación segetal presentó una mayor dominancia de especies (4.84.Twenty three species of leafhoppers were found in a sugar cane crop in San Pedro, Havana province, Cuba. Balclutha rufofasciata (Merino and Tylocygus geometricus (Signoret were new records for the crop. The samples were collected monthly from 1991- 1994 with entomological net. The most abundant and frequent species was B. guajanae (De Long (1 920 ind/ha in the crop and Hortensia similis Walk (18 960 ind/ha in the surrounding vegetation. Population dynamics was determined for each species. The surrounding vegetation was represented by Rottboellia cocninchinensis (Lourd. Clayton, Echinochloa colona (L. Link, Chamaesyce hyssopifolia (L. Small y Euphorbia heterophylla L. The sugar cane showed the highest spatial organization, diversity (0.61 and evennes (0.25. The surrounding vegetation had the highest species dominance.

  18. A reliable bioassay procedure to evaluate per os toxicity of Bacillus thuringiensis strains against the rice delphacid, Tagosodes orizicolus (Homoptera: Delphacidae

    Directory of Open Access Journals (Sweden)

    Rebeca Mora

    2007-06-01

    Full Text Available A reliable bioassay procedure was developed to test ingested Bacillus thuringiensis (Bt toxins on the rice delphacid Tagosodes orizicolus. Initially, several colonies were established under greenhouse conditions, using rice plants to nurture the insect. For the bioassay, an in vitro feeding system was developed for third to fourth instar nymphs. Insects were fed through Parafilm membranes on sugar (10 % sucrose and honey bee (1:48 vol/vol solutions, observing a natural mortality of 10-15 % and 0-5 %, respectively. Results were reproducible under controlled conditions during the assay (18±0.1 °C at night and 28±0.1 °C during the day, 80 % RH and a 12:12 day:light photoperiod. In addition, natural mortality was quantified on insect colonies, collected from three different geographic areas of Costa Rica, with no significant differences between colonies under controlled conditions. Finally, bioassays were performed to evaluate the toxicity of a Bt collection on T. orizicolus. A preliminary sample of twenty-seven Bt strains was evaluated on coarse bioassays using three loops of sporulated colonies in 9 ml of liquid diet, the strains that exhibited higher percentages of T. orizicolus mortality were further analyzed in bioassays using lyophilized spores and crystals (1 mg/ml. As a result, strains 26-O-to, 40-X-m, 43S-d and 23-O-to isolated from homopteran insects showed mortalities of 74, 96, 44 and 82 % respectively while HD-137, HD-1 and Bti showed 19, 83 and 95 % mortalities. Controls showed mortalities between 0 and 10 % in all bioassays. This is the first report of a reliable bioassay procedure to evaluate per os toxicity for a homopteran species using Bacillus thuringiensis strains. Rev. Biol. Trop. 55 (2: 373-383. Epub 2007 June, 29.Se desarrolló una metodología de bioensayo para evaluar toxinas de Bacillus thuringiensis (Bt ingeridas por Tagosodes orizicolus, plaga del arroz y vector del virus de la hoja blanca. Se establecieron colonias del insecto en condiciones de invernadero usando plantas de arroz como alimento. Para el bioensayo, se desarrolló un sistema de alimentación in vitro para ninfas de tercer y cuarto estadío. Los insectos se alimentaron de soluciones de miel de abeja (1:48 vol/vol y sacarosa (10 % a través de membranas de Parafilm. Se observaron mortalidades del 10-15 % y 0-5 %, respectivamente, en ambas dietas. Los resultados fueron reproducibles en condiciones controladas de humedad y temperatura (18±0.1 °C de noche y 28±0.1 °C de día, 80 % H.R y a 12:12 fotoperíodo día:noche. Asimismo, se analizó la mortalidad natural de los insectos según su procedencia, sin embargo, no se observaron diferencias significativas en condiciones controladas. Finalmente, se elaboraron bioensayos para evaluar la toxicidad de una colección de cepas de Bt contra T. orizicolus. Se evaluó preliminarmente, una submuestra de 27 cepas de Bt en bioensayos burdos usando tres asadas como inóculo para 9 ml de dieta líquida. Posteriormente, las cepas que mostraron los mayores porcentajes de mortalidad se evaluaron en bioensayos usando esporas y cristales liofilizados (1 mg/ml. Como resultado, las cepas aisladas a partir de homópteros 26-O-to, 40-X-m, 43-S-d y 23-O-to mostraron mortalidades de 74, 96, 44 y 82 % respectivamente, mientras que las HD-137, HD-1 y Bti mostraron 19, 83 y 95 % de mortalidad. Los controles presentaron mortalidades de 0 y 10 % en los bioensayos. Este es el primer informe de un bioensayo para evaluar la toxicidad de cepas de Bt utilizando la especie T. orizicolus.

  19. Herencia de la resistencia al daño mecánico causado por Tagosodes orizicolus (Muir (Homoptera-Delphacidae en arroz Oryza sativa

    Directory of Open Access Journals (Sweden)

    Cuevas P. Federico

    1996-12-01

    Full Text Available

    In Colombia all rice varieties developed are reported as resistant to Tagosodes orizicolus. Given the narrow genetic base of the resistant sources, this study was undertaken to identify the resistant parents or donors more oftenly used in Latin America. The materials were characterized as resistant (Mudgo, Amistad 82, IRAT 120, IRAT 124, Makalioka or susceptible based on the free chosen test and non chosen test and on the survival and oviposition of the insect (Chianan 8, Colombia 1, Bluebonnet 50, IR 8 (lCA, IR 8 (IRRI, Tetep and Cica 8. The damage was associated with insect survival, oviposition and eggs eclotion. To determine heritability two parents (Makalioka and Mudgo, were crossed with IR 8 F1 and F3 populations were also evaluated based on the free chosen test.

     

     

    En Colombia las variedades de arroz desarrolladas se consideran como resistentes a Tagosodes orizicolus. Dada la estrechez genética de las fuentes de resistencia, se inició este estudio para identificar los progenitores donantes de resistencia usados con mayor frecuencia en América Latina. Los materiales se caracterizaron como resistentes (Mudgo, Amistad 82, IRAT, 120, IRAT 124 Y Makalioka o susceptibles (Chianan 8, Colombia 1, Bluebonnet 50, IR 8 (lCA, IR (IRRI, Tetep y Cica 8, con base en las pruebas de libre escogencia, no escogencia, sobre vivencia y oviposición. El daño estuvo asociado con la supervivencia, oviposición y eclosión de huevos del insecto. Para la determinación de la herencia se cruzaron los progenitores Makalioka y Mudgo con IR8. En la Progenie F1 del cruzamiento resistente x resistente el 111% de las plantas fueron susceptibles; Mudgo y Makalioka segregaron 23 y 41% de plantas susceptibles.

  20. Is photosynthetic transcriptional regulation in Triticum aestivum L. cv. 'TugelaDN' a contributing factor for tolerance to Diuraphis noxia (Homoptera: Aphididae)?

    Science.gov (United States)

    Botha, Anna-Maria; Lacock, Lynelle; van Niekerk, Chantal; Matsioloko, M Thuto; du Preez, Franco B; Loots, Shilo; Venter, Eduard; Kunert, Karl J; Cullis, Christopher A

    2006-02-01

    Diuraphis noxia (Russian wheat aphid, RWA) is a major pest on wheat in South Africa and most other wheat growing countries. Being a probing-sucking insect, RWAs insert their stylets into the phloem sieve elements and feed on the phloem sap. This feeding causes necrotic lesions in resistant varieties, or decoloration of leaves and death in susceptible varieties. In an effort to broaden our understanding on the response of the plant to RWA feeding, we synthesized and analyzed expressed sequence tags (ESTs) from suppression subtractive hybridization (SSH) libraries. These libraries were constructed using near isogenic wheat lines susceptible "Tugela" and resistant "TugelaDN" (Dn1) to RWA, as well as accession lines PI137739 (Dn1) and PI294994 (Dn5). Analysis of 200 ESTs from the libraries revealed the involvement of transcripts encoding genes involved in cell maintenance, growth and regulation, plant defense and signaling, photosynthesis and energy production, and of unknown function. A selection of these ESTs, in combination with clones obtained from other sources, were used on a custom array to study the expression profiles of 256 candidate wheat sequences putatively involved in plant defense against RWA. The selected sequences included wheat genomic clones with putative nucleotide binding site (NBS) motifs, rapid amplification of cDNA ends PCR (RACE-PCR), and cDNA clones from RWA induced libraries. Genomic banana and flax clones that were obtained using representative difference analysis (RDA), and suspected to be involved in abiotic stress responses, were also spotted onto the microarray slides. The spotted custom arrays were then hybridized against cDNA isolated from a resistant cultivar "TugelaDN" on 0, 2, 5, and 8 days after infestation, post-labeled with Cy3- or Cy5-fluorescent dyes. The subsequent expression profiling using DNA microarray, RT-PCR, and Northern Blot analysis identified 29 transcripts associated with the feeding response. These transcripts encoded proteins functioning in direct defense and signaling, oxidative burst, cell wall degradation, cell maintenance, photosynthesis, and energy production. Results indicate that plants co-ordinately regulate gene expression when attacked by RWA. It is hypothesized that the NBS-LRR proteins are important in receptor recognition and signaling, which enable the plant to overcome the stresses inflicted by RWA feeding. It is further suggested that the ability to maintain photosynthetic function with resultant energy production is one of the determining factors ensuring the survival of the resistant varieties when coping with the RWA feeding.

  1. Primer registro de “la mosca negra de los cítricos” Aleurocanthus woglumi (Hemiptera: Aleyrodidae en la Argentina

    Directory of Open Access Journals (Sweden)

    Silvia N. LÓPEZ

    2011-01-01

    Full Text Available Aleurocanthus woglumi Ashby es una especie polífaga que ataca principalmente cultivos de Citrus spp. El objetivo de este trabajo es dar a conocer la primera detección de A. woglumi en Argentina. Los especímenes estudiados fueron recolectados en cultivos de pomelo en Tres Lagunas, departamento de Pilagá, Formosa, en febrero de 2011.

  2. Whiteflies (Hemiptera: Aleyrodidae) and the predator Delphastus pusillus (Le Conte) (Coleoptera: Coccinellidae) on papaya tree (Carica papaya L.) grown under screened conditions

    OpenAIRE

    Vieira, Marineide R.; Correa, Luiz S.

    2001-01-01

    Em fevereiro e outubro de 1998, na área experimental da Fazenda de Ensino e Pesquisa da UNESP no município de Selvíria-MS (latitude 20° 22' S, longitude 51° 22' W, altitude 335 m), foi constatada a presença de mosca branca em mamoeiro cultivar Baixinho de Santa Amália, plantado no interior de um telado com malha de 2 x 2 mm. Essa área fazia parte de um experimento visando determinar o efeito do cultivo em ambiente protegido sobre o desenvolvimento das plantas, a produção de frutos e a...

  3. Pre shipping dip treatments using soap, natural oils, and Isaria fumosorosea: potential biopesticides for mitigating the spread of whitefly Bemisia tabaci (Hemiptera: Aleyrodidae) invasive insects on ornamental plants

    Science.gov (United States)

    The whitefly Bemisia tabaci (Hemiptera: Aleyodidae) is an invasive insect pest affecting different crops including vegetables, fruits, cereals, and ornamentals. The efficacy of some products such as commercial soap, natural oils and Preferal® (based on the entomopathogenic fungus Isaria fumosorosea ...

  4. Medición indirecta de la tasa de consumo de adultos e inmaduros de Trialeurodes vaporariorum (Hemiptera: Aleyrodidae sobre fríjol

    Directory of Open Access Journals (Sweden)

    Luisa Fernanda Suarez Gonzalez

    2015-09-01

    Full Text Available La biología y ecología de la mosca blanca de los invernaderos, Trialeurodes vaporariorum (Westwood (Hemiptera: Aleyroridae, se encuentra ampliamente documentada. Sin embargo, hasta el momento no hay reportes acerca de la tasa de consumo de alimento por este fitófago, un parámetro necesario para modelos de simulación. Por tal motivo, el objetivo de esta investigación fue la medición indirecta del consumo de alimento por el adulto e instares inmaduros de T. vaporariorum basado en metodologías encontradas en la literatura científica. La estimación de la tasa de consumo de alimento por adultos se realizó bajo condiciones de laboratorio, utilizando como unidad experimental una planta de fríjol de dos semanas de edad. El experimento consistió de dos tratamientos: (T1 plantas libres de cualquier fitófago y (T2 plantas sometidas a infestaciones con T. vaporariorum, cada tratamiento con 20 repeticiones y una réplica en el tiempo de todo el experimento. Se registró el peso fresco diariamente en ambos tratamientos. Para el caso de los inmaduros, la unidad experimental consistió en una hoja cotiledónea de fríjol, infestada con una población determinada de inmaduros de cada instar de mosca blanca teniendo así cinco tratamientos (Instar I, II, III, IV y Control cada uno con 17 repeticiones. Se registró diariamente el peso fresco de las hojas. Se obtuvo un consumo promedio de alimento por el adulto de 0,277 ± 0,0042 mg.dia-1. Para los dos primeros instares ninfales se estimó una tasa de consumo de 0,052 mg.dia-1, en el tercer instar de 0,14 mg.dia-1, y para el cuarto instar de 0,19 mg.dia-1. Un adulto de mosca blanca puede consumir en un día seis veces su peso y un inmaduro ocho veces, gracias a su rápido metabolismo y la constante excreción de mielecilla.

  5. Quantification and localization of Watermelon chlorotic stunt virus and Tomato yellow leaf curl virus (Geminiviridae in populations of Bemisia tabaci (Hemiptera, Aleyrodidae with differential virus transmission characteristics.

    Directory of Open Access Journals (Sweden)

    Mario Kollenberg

    Full Text Available Bemisia tabaci (Gennadius is one of the economically most damaging insects to crops in tropical and subtropical regions. Severe damage is caused by feeding and more seriously by transmitting viruses. Those of the genus begomovirus (Geminiviridae cause the most significant crop diseases and are transmitted by B. tabaci in a persistent circulative mode, a process which is largely unknown. To analyze the translocation and to identify critical determinants for transmission, two populations of B. tabaci MEAM1 were compared for transmitting Watermelon chlorotic stunt virus (WmCSV and Tomato yellow leaf curl virus (TYLCV. Insect populations were chosen because of their high and respectively low virus transmission efficiency to compare uptake and translocation of virus through insects. Both populations harbored Rickettsia, Hamiltonella and Wolbachia in comparable ratios indicating that endosymbionts might not contribute to the different transmission rates. Quantification by qPCR revealed that WmCSV uptake and virus concentrations in midguts and primary salivary glands were generally higher than TYLCV due to higher virus contents of the source plants. Both viruses accumulated higher in insects from the efficiently compared to the poorly transmitting population. In the latter, virus translocation into the hemolymph was delayed and virus passage was impeded with limited numbers of viruses translocated. FISH analysis confirmed these results with similar virus distribution found in excised organs of both populations. No virus accumulation was found in the midgut lumen of the poor transmitter because of a restrained virus translocation. Results suggest that the poorly transmitting population comprised insects that lacked transmission competence. Those were selected to develop a population that lacks virus transmission. Investigations with insects lacking transmission showed that virus concentrations in midguts were reduced and only negligible virus amounts were found at the primary salivary glands indicating for a missing or modified receptor responsible for virus attachment or translocation.

  6. Bemisia tabaci MED (Q biotype) (Hemiptera: Aleyrodidae)is on the move in Florida to residential landscapes and may impact open field agriculture

    Science.gov (United States)

    Bemisia tabaci MED (Mediterranean) have been in the United States for approximately a dozen years spreading to 26 states since it was first detected in Arizona at a retail outlet on poinsettia in 2004. Indistinguishable morphologically from silverleaf whitefly (Bemisia tabaci MEAM1 (Middle Eastern A...

  7. A new silverleaf inducing biotype of Bemisia tabaci (Hemiptera: Aleyrodidae) Ms, indigenous for the islands of the South West Indian Ocean

    NARCIS (Netherlands)

    Delatte, H.; Reynaud, B.; Granier, M.; Thornary, L.; Lent, van J.W.M.; Goldbach, R.W.; Peterschmitt, M.

    2005-01-01

    Following the first detection of tomato yellow leaf curl virus (TYLCV) from Réunion (700 km east of Madagascar) in 1997 and the upsurge of Bemisia tabaci (Gennadius) on vegetable crops, two genetic types of B. tabaci were distinguished using RAPD¿PCR and cytochrome oxidase I (COI) gene sequence

  8. Biological parameters of Bemisia tabaci (Gennadius) biotype B (Hemiptera: Aleyrodidae) on Jatropha gossypiifolia, commercial (Manihot esculenta) and wild cassava (Manihot flabellifolia and M. carthaginensis) (Euphorbiaceae).

    Science.gov (United States)

    Carabalí, Arturo; Belloti, Anthony C; Montoya-Lerma, James

    2010-01-01

    Bemisia tabaci (Gennadius) is one of the most important pests of cassava in Africa and several countries of Asia due to the damage caused by direct feeding, the excretion of honeydew, and its capacity as a vector of cassava mosaic geminivirus. There is a general consensus that B. tabaci is a complex of morphologically indistinguishable populations with different biotypes. In the Americas, the polyphagous biotype B does not appear to feed on cassava. Recent studies indicate that it is possible, however, for biotype B to gradually adapt to cassava using phylogenetically related hosts. Therefore, the possibility that some wild species of cassava constitute intermediate hosts in the adaptation process may lead to the establishment of biotype B on commercial varieties of Manihot esculenta. In here, we evaluated Jatropha gossypiifolia, two wild species of cassava (Manihot flabellifolia and M. carthaginensis) and a commercial cassava variety (MCol 2063) as hosts of biotype B. The highest oviposition rate (2.7 eggs /two days) occurred on M. esculenta, although the development time (44 d) was the longest when compared to M. carthaginensis and J. gossypiifolia. About 60% of the population could reproduce on the wild cassava species vs. 55% on J. gossypiifolia and 27.5% on the commercial variety. Our data suggest that J. gossypiifolia is a suitable host and the wild species M. carthaginensis can constitute a potential intermediate host in the adaptation of biotype B to commercial varieties of cassava.

  9. Evaluation of Bioinsecticides for Management of Bemisia tabaci (Hemiptera: Aleyrodidae) and the Effect on the Whitefly Predator Delphastus catalinae (Coleoptera: Coccinellidae) in Organic Squash.

    Science.gov (United States)

    Razze, Janine M; Liburd, Oscar E; Nuessly, Gregg S; Samuel-Foo, Michelle

    2016-08-01

    Organic zucchini squash is a high-value vegetable crop in Florida and potential exists to expand its production throughout the state. A lack of knowledge on the effectiveness of organic products and their integration with natural enemies is an important constraint to the regulation of pest populations in organic squash production in Florida. The objectives of this study were to evaluate the effect of insecticides labeled for organic production that can be used for management of Bemisia tabaci (Gennadius) biotype B, on organically grown squash; and to determine the effects of the most efficient insecticides on a key natural enemy, Delphastus catalinae (Horn). Experiments were conducted in the greenhouse in exclusion cages. The first experiment compared the effects of four bioinsecticides on whitefly densities. Insecticides include 1) AzaSol (azadirachtin), 2) PyGanic EC 1.4 (pyrethrin), 3) M-Pede (insecticidal soap), and 4) Entrust (spinosad). The second experiment investigated the effects of bioinsecticides on D. catalinae Treatment effectiveness was evaluated 1, 3, and 5 d posttreatment. PyGanic and M-Pede were highly effective in controlling whitefly populations on organic squash, while moderate control was provided by AzaSol and there was no control provided by Entrust. PyGanic and M-Pede treatments reduced D. catalinae populations when adults were released 1 d post pesticide application. However, when adults were released 5 d post application, there was no reduction. The importance of using bioinsecticides in combination with natural enemies to regulate pest populations in organic cropping systems is discussed. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Keanekaragaman dan Kelimpahan Musuh Alami Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae pada Pertanaman Cabai Merah di Kecamatan Pakem, Kabupaten Sleman, Daerah Istimewa Yogyakarta

    Directory of Open Access Journals (Sweden)

    Hendrival Hendrival

    2015-09-01

    Full Text Available Research on natural enemies of Bemisia tabaci was conducted in the chili pepper fields in Sub-district of Pakem, District of Sleman, The Special Province of Yogyakarta during the dry season of May-October 2009. The aims of this research were to study the diversity and abundance of parasitoid and predator species associated with B. tabaci. Samplings of insect species were done using yellow pan trap, sweep net, direct observation of insects colonized young leaves, and collection of nymphs for B. tabaci. Measurement of insect diversity was calculated using Shannon’s index diversity and Evenness index. Nine species of insect predator were identified, i.e. Harmonia octomaculata (Fabricius, Menochilus sexmaculata (Fabricius, Scymnus sp., Micraspis inops Mulsant, Coccinella sp. (Coleoptera: Coccinellidae, Paederus fuscipes Curtis (Coleoptera: Staphylinidae, Orius sp. (Hemiptera: Anthocoridae, Linyphiidae sp.1 (Araneae, and Syrphidae sp.1 (Diptera. Eretmocerus sp. (Hymenoptera: Aphelinidae was the only parasitoid found in the nymphs B. tabaci collected and has the potential to control B. tabaci in the red pepper fields.

  11. Deep Sequencing-Based Transcriptome Analysis Reveals the Regulatory Mechanism of Bemisia tabaci (Hemiptera: Aleyrodidae Nymph Parasitized by Encarsia sophia (Hymenoptera: Aphelinidae.

    Directory of Open Access Journals (Sweden)

    Yingying Wang

    Full Text Available The whitefly Bemisia tabaci is a genetically diverse complex with multiple cryptic species, and some are the most destructive invasive pests of many ornamentals and crops worldwide. Encarsia sophia is an autoparasitoid wasp that demonstrated high efficiency as bio-control agent of whiteflies. However, the immune mechanism of B. tabaci parasitization by E. sophia is unknown. In order to investigate immune response of B. tabaci to E. Sophia parasitization, the transcriptome of E. sophia parasitized B. tabaci nymph was sequenced by Illumina sequencing. De novo assembly generated 393,063 unigenes with average length of 616 bp, in which 46,406 unigenes (15.8% of all unigenes were successfully mapped. Parasitization by E. sophia had significant effects on the transcriptome profile of B. tabaci nymph. A total of 1482 genes were significantly differentially expressed, of which 852 genes were up-regulated and 630 genes were down-regulated. These genes were mainly involved in immune response, development, metabolism and host signaling pathways. At least 52 genes were found to be involved in the host immune response, 33 genes were involved in the development process, and 29 genes were involved in host metabolism. Taken together, the assembled and annotated transcriptome sequences provided a valuable genomic resource for further understanding the molecular mechanism of immune response of B. tabaci parasitization by E. sophia.

  12. A study of the super-abundant Bemisia tabaci (Gennadius) species complex (Hemiptera: Aleyrodidae) in cassava Mosaic disease pandemic areas in Tanzania

    DEFF Research Database (Denmark)

    Tajebe, Lensa Sefera

    and forcing some farmers to abandon the cultivation of the crop. The severe CMD pandemic is mainly characterized by high severity and incidence of the disease dominated by whitefly-borne infection and super-abundant populations of B. tabaci. All Bemisia tabaci individuals harbour a primary bacterial symbiont......; and (iii) to investigate the population structure of and the possibilities of gene flow between B. tabaci populations found in CMD pandemic affected and not yet affected parts of Tanzania. Hence, several field surveys were conducted in CMD pandemic-affected and unaffected areas in Tanzania and whiteflies...... established SSA1-SG1 to be the pandemic-associated B. tabaci in Tanzania, being found predominantly in the pandemic affected north-western part of the country. B. tabaci abundance and mean CMD severity values were highest for north-western Tanzania, matching the characteristic of the pandemic. The SSA1-SG2...

  13. Asymmetric consequences of host plant occupation on the competition between the whiteflies Bemisia tabaci cryptic species MEAM1 and Trialeurodes vaporariorum (Hemiptera: Aleyrodidae)

    DEFF Research Database (Denmark)

    Zhang, Gui-Fen; Lövei, Gabor L; Hu, Man

    2014-01-01

    BACKGROUND: The two common whitefly species, Bemisia tabaci (Gennadius) MEAM1 and Trialeurodes vaporariorum (Westwood), often co-occur on their host plants. The effect of host plant occupation by one species on later-arriving conspecific individuals or on the other competing species was examined....... RESULTS: Resource preoccupied by T. vaporariorum had mostly negative effects on the life history parameters of later-arriving conspecifics. Red-eyed nymph and immature survival of T. vaporariorum decreased when resource was preoccupied by conspecifics, irrespective of the previous occupation scenario....... However, resource preoccupied by T. vaporariorum had only minor detrimental effectsonthe performanceof later-arriving B. tabaci MEAM1.In theopposite colonisation sequence, previous occupation by B. tabaci MEAM1 had no significant effects on the life history parameters of later-arriving conspecifics...

  14. The Trouble with MEAM2: Implications of Pseudogenes on Species Delimitation in the Globally Invasive Bemisia tabaci (Hemiptera: Aleyrodidae) Cryptic Species Complex.

    Science.gov (United States)

    Tay, Wee Tek; Elfekih, Samia; Court, Leon N; Gordon, Karl H J; Delatte, Hélène; De Barro, Paul J

    2017-10-01

    Molecular species identification using suboptimal PCR primers can over-estimate species diversity due to coamplification of nuclear mitochondrial (NUMT) DNA/pseudogenes. For the agriculturally important whitefly Bemisia tabaci cryptic pest species complex, species identification depends primarily on characterization of the mitochondrial DNA cytochrome oxidase I (mtDNA COI) gene. The lack of robust PCR primers for the mtDNA COI gene can undermine correct species identification which in turn compromises management strategies. This problem is identified in the B. tabaci Africa/Middle East/Asia Minor clade which comprises the globally invasive Mediterranean (MED) and Middle East Asia Minor I (MEAM1) species, Middle East Asia Minor 2 (MEAM2), and the Indian Ocean (IO) species. Initially identified from the Indian Ocean island of Réunion, MEAM2 has since been reported from Japan, Peru, Turkey and Iraq. We identified MEAM2 individuals from a Peruvian population via Sanger sequencing of the mtDNA COI gene. In attempting to characterize the MEAM2 mitogenome, we instead characterized mitogenomes of MEAM1. We also report on the mitogenomes of MED, AUS, and IO thereby increasing genomic resources for members of this complex. Gene synteny (i.e., same gene composition and orientation) was observed with published B. tabaci cryptic species mitogenomes. Pseudogene fragments matching MEAM2 partial mtDNA COI gene exhibited low frequency single nucleotide polymorphisms that matched low copy number DNA fragments (species. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  15. EFICIÊNCIA DO CONTROLE QUÍMICO SOBRE A MOSCA BRANCA Bemisia tabaci biótipo B (HEMIPTERA: ALEYRODIDAE EM MELOEIRO

    Directory of Open Access Journals (Sweden)

    Antônio Lindemberg Martins Mesquita

    2007-01-01

    efficient to control eggs, nymphs and adults of the whitefly, while the insect growth regulators buprofezin and pyriproxyfen did not control eggs and adults, but they controled nymphs, being pyriproxyfen more efficient than buprofezin.

  16. Deep Sequencing-Based Transcriptome Analysis Reveals the Regulatory Mechanism of Bemisia tabaci (Hemiptera: Aleyrodidae) Nymph Parasitized by Encarsia sophia (Hymenoptera: Aphelinidae).

    Science.gov (United States)

    Wang, Yingying; Xiao, Da; Wang, Ran; Li, Fei; Zhang, Fan; Wang, Su

    2016-01-01

    The whitefly Bemisia tabaci is a genetically diverse complex with multiple cryptic species, and some are the most destructive invasive pests of many ornamentals and crops worldwide. Encarsia sophia is an autoparasitoid wasp that demonstrated high efficiency as bio-control agent of whiteflies. However, the immune mechanism of B. tabaci parasitization by E. sophia is unknown. In order to investigate immune response of B. tabaci to E. Sophia parasitization, the transcriptome of E. sophia parasitized B. tabaci nymph was sequenced by Illumina sequencing. De novo assembly generated 393,063 unigenes with average length of 616 bp, in which 46,406 unigenes (15.8% of all unigenes) were successfully mapped. Parasitization by E. sophia had significant effects on the transcriptome profile of B. tabaci nymph. A total of 1482 genes were significantly differentially expressed, of which 852 genes were up-regulated and 630 genes were down-regulated. These genes were mainly involved in immune response, development, metabolism and host signaling pathways. At least 52 genes were found to be involved in the host immune response, 33 genes were involved in the development process, and 29 genes were involved in host metabolism. Taken together, the assembled and annotated transcriptome sequences provided a valuable genomic resource for further understanding the molecular mechanism of immune response of B. tabaci parasitization by E. sophia.

  17. POTENCY OF PREDATOR (Menochilus sexmaculatus AUGMENTATION FOR WHITE FLY (Bemisia tabaci MANAGEMENT AND ITS EFFECT ON GEMINI VIRUS INFESTATION ON TOMATO

    Directory of Open Access Journals (Sweden)

    W. Setiawati

    2013-04-01

    Full Text Available Bemisia tabaci (Gen. (Homoptera: Aleyrodidae is one of the most serious pests on tomato. It is mainly controlled by chemi-cal means, requiring some 25 sprays during the average growing season. The extensive and repeated use of insecticides has dis-rupted the natural balance between this pest and its natural enemies. In this study, Menochilus sexmaculatus F. was evalu-ated as a possible biological control agent of B. tabaci and its effect on Gemini virus infestation. The study was conducted at the experimental station of the Indonesian Vegetables Research Institute (IVeGRI in Lembang, West Java (1,250 m above sea level from August to December 2008. The experimental plots consisted of 0.35 ha of tomato (± 100 m2 per plot and spatially separated with four rows of maize (a minimum of 1 m inter-plot distance to prevent cross-contamination among plots. The experiment was arranged in completely randomized block design with eight treatments and four replications. M. sexmaculatus were released at 24 days after planting. The treatments were designed according dosages and schedules at three released populations (i.e. 10 predators per plot, 20 predators per plot, and 10 predators per plot at vegetative stage followed by 20 predators per plot at generative stage; two places of release (center and edge of the plot; and two schedules of release (weekly and biweekly. Efficacy of the predator was measured in terms of the density of B. tabaci, both before and after release of the predator and its effect on Gemini virus infestation. The result indicated the potential use of M. sexmaculatus to control B. tabaci and its effect on Gemini virus infestation on tomato. Reductions in B. tabaci populations and subsequent tomato yields were significant. B. tabaci population in plots receiving 10 predators showed 73.62% and 75.75% reductions by the end of experiment. The incidence and intensity of Gemini virus were consistently and significantly lowest and tomato yield

  18. A Molecular Phylogeny of Hemiptera Inferred from Mitochondrial Genome Sequences

    OpenAIRE

    Nan Song; Ai-Ping Liang; Cui-Ping Bu

    2012-01-01

    Classically, Hemiptera is comprised of two suborders: Homoptera and Heteroptera. Homoptera includes Cicadomorpha, Fulgoromorpha and Sternorrhyncha. However, according to previous molecular phylogenetic studies based on 18S rDNA, Fulgoromorpha has a closer relationship to Heteroptera than to other hemipterans, leaving Homoptera as paraphyletic. Therefore, the position of Fulgoromorpha is important for studying phylogenetic structure of Hemiptera. We inferred the evolutionary affiliations of tw...

  19. Luta biológica clássica com Hyperaspis pantherina Fürsch (Coleoptera: Coccinellidae no combate à Orthezia insignis Browne (Homoptera: Ortheziidae em jacarandá Biological control with Hyperaspis pantherina Fürsch (Coleoptera: Coccinellidae to control Orthezia insignis Browne (Homoptera: Ortheziidae on blue jacaranda

    Directory of Open Access Journals (Sweden)

    Ana Paula Félix

    2008-12-01

    Full Text Available Os jacarandás e várias plantas ornamentais que ornamentam passeios e áreas ajardinadas da cidade do Funchal encontram-se infestados pela cochonilha Orthezia insignis Browne. Para combater esta praga foi importada do Quénia, uma joaninha, Hyperaspis pantherina Fürsch. Este predador é específico de O. insignis e tem sido utilizado, com sucesso em programas de luta biológica, em vários países de África, no Peru, Hawai e na Ilha de Santa Helena. Na Ilha da Madeira, desde Julho de 2002, H. pantherina está a ser criado em laboratório e largado em jacarandás infestados com o objectivo de combater a cochonilha-dojacarandá através da luta biológica clássica. Referem-se as largadas de H. pantherina e o sistema de monitorização adoptado para verificar a aclimatação do predador.The Jacaranda trees and other ornamental plants used in sidewalks and gardenlike areas of sidewalks and other gardened areas of the downton Capital city of Madeira Island (Funchal, are infested by the Jacaranda or Lantana Bug, Orthezia insignis Browne. A ladybird, Hyperaspis pantherina Fürsch, was imported from Kenya to control this pest. This ladybird is a specific predator of O. insignis and it has been used, successfully in biological control programs, in several countries of Africa, in Peru, Hawaii and in Santa Helena Island. In Madeira Island, H. pantherina is being reared in laboratory and released into infested jacarandas since July 2002, in a classical biological control way. The releasing of H. pantherina is described in detail as well as the adopted monitoring system to verify its acclimation.

  20. Membracidos de Colombia - I. Revisión parcial de las especies del género Alchisme Kirkaldy (Homoptera: Membracidae: Hoplophorioninae Membracidos de Colombia - I. Revisión parcial de las especies del género Alchisme Kirkaldy (Homoptera: Membracidae: Hoplophorioninae

    Directory of Open Access Journals (Sweden)

    Restrepo Mejía Ruben

    1980-09-01

    Full Text Available Se revisó el género Alchisme Kirkaldy. De las diecinueve especies anotadas por Metcalf (1965 no se obtuvieron especímenes de A. apicalis (Walker, A. costaricensis Goding, A. elevata Goding, A. laticornis Funkhouser, A. pinguicornisFunkhouser, A. recurva (Stäl, A. spinosa Funkhouser y A. truncaticornis (Germar. Se incluyen las descripciones originales de estas especies y tentativamente se localizan en la clave presentada. Se redescriben: A. bos (Fairmaire, A. fastidiosa (Fairmaire, A. grossa (Fairmaire, A. inermis (Fairmaire, A. nigrocarinata (Fairmaire, A. rubrocostata (Spinola, A. turrita (Germar, A. ustulata (Fairmaire, A. virescens (Fairmaire y A. nigrocarinata var. tridentata (Fairmaire, para la cual se usa su combinación original A. tridentata (Fairmaire. Se sinonimizóa A. projecta Funkhouser en favor de A. bos (Fairmaire.Se ilustran las principales características del pronoto y de los genitales de los machos; se observaron y se obtuvieron fotografías de los edeagos en un microscopio electrónico "rastreador" (Scanning Electro Microscope, las cualesse incluyen como parte de las ilustraciones. Se analizó la distribución geográfica del género y se ilustró por medio de mapas.The genus Alchisme Kirkaldy was revised. From nineteen species listed by Metcalf (1965 not specimens were obtained of eight of them. Original descriptions of these species are included and tentatively are localized in the key.  A redescription is given for the species A. bos (Fairmaire, A. fastidiosa (Fairmaire, A. grossa (Fairmaire, A. inermis (Fairmaire, A. nigrocarinata (Fairmaire, A. rubrocostata (Spinola, A. turrita (Germar, A. ustulata (Fairmaire, A. virescens (Fairmaire y A. nigrocarinata var. tridentata (Fairmaire, for which was used the original combination A. tridentata (Fairmaire. A. projecta Funkhouser was synonymized in A. bos (Fairmaire. The main pronotum characters and male genitalia are illustred; Scanning Electro Microscope pictures of the aedeagus of the insects were observed and obtained and are included as part of the illustrations. Geographic distributionsof the genus was analized and maps were prepared.

  1. Efecto de la configuración de lotes de gramíneas invernales sobre poblaciones de Delphacidae (Insecta: Homoptera en dispersión The effect of the configuration of winter grass plots on dispersing populations of Delphacidae (Insecta: Homoptera

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    M.A. Bruno

    2007-12-01

    Full Text Available Las características del paisaje afectan la distribución y abundancia de los insectos dentro y entre los lotes de cultivos. El objetivo de este trabajo fue determinar el efecto de los elementos del paisaje agrícola sobre la abundancia de los individuos en dispersión de las especies de Delphacidae. Éstas son vectores de virus patogénicos que transmiten enfermedades de importancia económica para la producción agropecuaria. El estudio se realizó en el área central de la provincia de Córdoba, Argentina; los insectos fueron capturados con trampas pegajosas ubicadas dentro de parches de hospedadores. Las métricas del paisaje analizadas fueron: área del parche, índice de proximidad media y porcentaje del paisaje cubierto por parches de una clase de hospedador. La abundancia de Delphacodes kuscheli tuvo relación positiva con el área de los parches de pasturas de invierno. El índice de proximidad media tuvo relación positiva con las abundancias de D. kuscheli y D . balboae en los parches de pasturas de invierno y el porcentaje del paisaje cubierto con parches de pasturas de invierno se relacionó positivamente con las abundancias de D. kuscheli, D. balboae y D. haywardi. Las abundancias de Toya propincua no mostraron relación con ninguna de las métricas del paisaje analizadas.Landscape configuration can affect the distribution and abundance of insect species. The objective of this work was to determine the effect of landscape elements configuration on the abundance of dispersing individuals of Delphacidae species. Delphacid species are important vectors of pathogenic viruses causing diseases of economic importance on grain production. The study was performed in the central area of Córdoba Province, Argentina; the insects were collected with sticky traps placed in plant host patches. The landscape metrics estimated were: host patch area, Mean Proximity Index (MPI and the Percentage of Landscape occupied (PLAND by host patches of the same class. The abundance of Delphacodes kuscheli showed a positive relationship with patch area of the winter pastures. There was a positive relationship between Mean Proximity Index of winter pastures patches and D. kuscheli and D . balboae abundances. The Percentage of Landscape occupied by the winter pastures patches also showed a positive relationship with Delphacodes kuscheli, Delphacodes balboae and Delphacodes haywardi abundances. Finally we found no relationship between Toya propinqua abundance and any of the landscape metrics analyzed in this work. These results show that landscape configuration has a different effect on the dispersing population of the different species of Delphacidae.

  2. Population dynamics of the small spruce whorl scale (Physokermes hemicryphus DALM. Homoptera, Coccidea) taking into account forest damage from air pollution in various spruce sites in Baden-Wuerttemberg; Populationsdynamik der kleinen Fichtenquirlschildlaus (Physokermes hemicryphus DALM. Homoptera, Coccidea) unter Beruecksichtigung der Waldschaeden durch Luftverschmutzung an verschiedenen Fichtenstandorten in Baden-Wuerttemberg

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, W.

    1991-12-19

    From 1984 to 1986 the mass variation of Physokermes hemicryphus was investigated in spruce stands in the field damaged in varying degrees by air pollutants. The influence of the nutritive element contents of potassium, calcium, phosphorus, magnesium and nitrogen on needle weight, needle loss, and the population density of Physokermes hemicryphus was examined. The sites of investigation were in southern Germany. Further tests were conducted in 1986 in the open-top chambers of the University of Hohenheim, on the influence of defined air pollutants or combinations of air pollutants. Specifically, their effect on the nutritive element content of cloned young spruces, and their influence on the size of Physokermes hemicryphus specimens were assessed. The mineral content of honey dew was analysed in addition. Spruce stands in southern Germany which are seriously damaged by air pollutants tend to have below-average rates of colonization with whorl scales. During the period of investigation, the population density of Physokermes hemicryphus declined in all sites. On average, 44% of the decline was accounted for by parasites and predators. (orig./UWA) [Deutsch] Im Freiland wurde an Fichtenbestaenden die durch Luftschadstoffe verschieden stark beschaedigt waren, in den Jahren 1984-1986 der Massenwechsel von Physokermes hemicryphus untersucht. Dabei wurde der Einfluss der Naehrelementgehalte Kalium, Kalzium, Phosphor, Magnesium und Stickstoff auf das Nadelgewicht, den Nadelverlust und die Populationsdichte von Physokermes hemicryphus geprueft. Die Untersuchungsstandorte lagen in Suedwestdeutschland. In den Open-Top Kammern der Universitaet Hohenheim erfolgten im Jahr 1986 weitere Untersuchungen zum Einfluss definierter Luftschadstoffe bzw. Luftschadstoffkombinationen. Geprueft wurden deren Effekt auf den Naehrelementgehalt von klonierten Jungfichten und die Auswirkungen auf die Koerpergroesse von Physokermes hemicryphus. Weiterhin wurde dort der Mineralstoffgehalt im Honigtau analysiert. Durch Luftschadstoffe staerker geschaedigte Fichtenbestaende in Suedwestdeutschland haben einen durchschnittlich eher niedrigen Besatz mit Quirlschildlaeusen. Im Untersuchungszeitraum ging in allen Standorten die Populationsdichte von Physokermes hemicryphus zurueck. An dem Rueckgang der Populationen waren Parasiten und Raeuber mit im Mittel 44% beteiligt. (orig./UWA)

  3. Aspectos biológicos de Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae alimentada com Bemisia tabaci (Gennadius, 1889 biótipo B (Hemiptera: Aleyrodidae criada em três hospedeiros Biological aspects of Chrysoperla externa (Hagen, 1861 (Neuroptera: Chrysopidae fed on Bemisia tabaci (Gennadius, 1889 biotype B (Hemiptera: Aleyrodidae reared in three hosts

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    Cláudio Gonçalves Silva

    2004-04-01

    Full Text Available Estudaram-se alguns aspectos biológicos de adultos de Chrysoperla externa (Hagen oriundos de larvas alimentadas com ninfas da mosca-branca Bemisia tabaci (Gennadius biótipo B, criadas em folhas de pepino (Cucumis sativus var. caipira, couve (Brassica oleraceae var. acephala e na planta invasora leiteiro (Euphorbia heterophylla. Discos foliares dos hospedeiros contendo ninfas de terceiro e quarto estádios da mosca-branca foram acondicionados em placas de Petri contendo ágar-água a 1%. Em cada placa foi colocada uma larva de C. externa recém-eclodida, onde permaneceram até a emergência dos adultos. Foram avaliados o peso logo após a emergência, os períodos de pré-oviposição, oviposição, efetivo de oviposição, pós-oviposição, número total de ovos produzidos por fêmea e longevidade. Avaliaram-se, também, o período embrionário e a viabilidade dos ovos, coletando-se, uma vez por semana, uma amostra de 10% do total de ovos produzidos no dia, ao longo de todo o período reprodutivo. O peso de machos e fêmeas não diferiu significativamente em função do hospedeiro da presa, sendo em média de 4,7 mg. De maneira geral, adultos de C. externa oriundos de larvas alimentadas com ninfas de B. tabaci biótipo B criadas em leiteiro apresentaram performance inferior em relação àqueles oriundos do pepino e da couve. O período de oviposição foi, em média, de 49,5 dias para o pepino e a couve, e de 31,6 dias para o leiteiro. A produção de ovos foi reduzida em aproximadamente 50% em leiteiro, sendo de 293,8 ovos; no pepino e couve, a média foi de 591,3 ovos. Ninfas de B. tabaci biótipo B criadas em leiteiro causaram uma redução da viabilidade dos ovos de C. externa, que foi 62,8% e 57,7% inferior ao verificado para o pepino e a couve, respectivamente.The aim was to study some biological aspects of adults of Chrysoperla externa (Hagen, from larvae fed on nymphs of third and fourth stages of Bemisia tabaci (Gennadius biotype B, and reared on leaves of cucumber (Cucumis sativus, kale (Brassica oleracea and wild poinsettia (Euphorbia heterophylla. Leaf discs from the hosts containing third and fourth stage nymphs of whitefly, were placed in Petri dishes containing 1% agar. One recently hatched larvae of C. externa was placed in each dish, until adult emergence. The weight after emergence,eoviposition, oviposition, effective oviposition and postoviposition periods, the total number of eggs per female and longevity were evaluated. The embryonic period and the survival rate of the eggs were also recorded by collecting weekly samples of 10% of the daily egg production, throughout the reproductive period. The weights of males and females did not differ in relation to the hosts, the average being 4.7 mg. In general, adults of C. externa, coming from larvae fed on B. tabaci biotype B nymphs reared on leaves of the host wild poinsettia, had their biological characters affected, in comparison with those on leaves of cucumber and kale. The oviposition period averaged 49.5 days for cucumber and kale, and 31.6 days for wild poinsettia. Egg laying capacity was reduced by 50% on wild poinsettia, its being 293.8 eggs. In cucumber and kale, the average was 591.3 eggs. Nymphs of B. tabaci biotype B reared on wild poinsettia caused increase of the embrionic period and a reduction of the survival rate of the eggs, its being 62.8% and 57.7% lower than that presented by the ones reared on cucumber and kale, respectively.

  4. Whitefly species (Hemiptera: Aleyrodidae on wild and cultivated plants in the horticultural region of Rosario, Santa Fe, Argentina Especies de moscas blancas (Hemiptera: Aleyrodidae sobre plantas silvestres y cultivadas en la región hortícola de Rosario, Santa Fe, Argentina

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    Gustavo G. Gonsebatt

    2012-06-01

    Full Text Available Whiteflies of economic importance are polyphagous, being able to develop on a large number of cultivated and spontaneous plants. We recorded the whitefly species on vegetable and flower crops and the wild plants associated, under greenhouse and field conditions, for two years. We observed two species: Trialeurodes vaporariorum (Westwood and the Bemisia tabaci complex (Gennadius. T vaporariorum was recorded on 24 plant species (11 families, 12 and 8 of which are new hosts in Argentina and in the world, respectively. The B. tabaci complex was recorded only on flower production systems, on 19 plant species (11 families, 14 and 7 of which are new hosts in Argentina and in the world, respectively. The crops Glycine max (L. and Chrysanthemum morifolium Ramat., the wild species Amaranthus blitum L., Amaranthus quitensis Kunth, Conyza bonariensis (L., Galinsoga parviflora Cav., Sonchus oleraceus L. and Wedelia glauca (Ortega O. Hoffm. ex Hicken were hosts of both species. The only parasitoid recorded was Eretmocerus californicus near corni Haldeman (Hymenoptera: Aphelinidae from T. vaporariorum. This study, which is the first systematic survey of host plants in the region, intends to provide a better knowledge of the range of whiteflies host plants in Argentina.Las moscas blancas de importancia económica son polífagas y capaces de desarrollarse sobre numerosas plantas cultivadas y espontáneas. Registramos las especies de moscas blancas sobre cultivos hortícolas y de flores, y sobre las plantas silvestres asociadas. Observamos dos especies: Trialeurodes vaporariorum (Westwood y el complejo Bemisia tabaci (Gennadius. T. vaporariorum fue registrada sobre 24 especies de plantas (11 familias, 12 y 8 de las cuales son hospedantes nuevos para Argentina y a nivel mundial, respectivamente. El complejo B. tabaci fue registrado solo en sistemas de producción de flores, sobre 19 especies de plantas (11 familias, 14 y 7 de las cuales son nuevos hospedantes para Argentina y a nivel mundial, respectivamente. Los cultivos Glycine max (L. y Chrysanthemum morifolium Ramat., las especies silvestres Amaranthus blitum L., Amaranthus quitensis Kunth, Conyza bonariensis (L., Galinsoga parviflora Cav, Sonchus oleraceus L. y Wedelia glauca (Ortega O. Hoffm. ex Hicken fueron hospedantes de ambas especies. El único parasitoide registrado fue Eretmocerus californicus cercano a corni Haldeman (Hymenoptera: Aphelinidae sobre T. vaporariorum. Este estudio que constituye el primer relevamiento sistemático de plantas hospedantes en la región, aporta un mayor conocimiento sobre el rango de plantas hospedantes de las moscas blancas en Argentina.

  5. Nuevos registros de especies del género Eretmocerus (Hymenoptera: Aphelinidae, parasitoides de Trialeurodes vaporariorum y el complejo Bemisia tabaci (Hemiptera: Aleyrodidae en Argentina New records of species of the genus Eretmocerus (Hymenoptera: Aphelinidae, parasitoids of Trialeurodes vaporariorum and Bemisia tabaci complex (Hemiptera: Aleyrodidae in Argentina

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    Silvia N. López

    2008-06-01

    Full Text Available El objetivo de este trabajo es dar a conocer nuevos registros y distribuciones de las especies del género Eretmocerus Haldeman, parasitoides de las dos especies de mosca blanca que tienen mayor importancia económica en cultivos hortícolas y ornamentales en Argentina. Una especie de Eretmocerus Haldeman fue hallada parasitando a Trialeurodes vaporariorum (Westwood en Santa Fe y Buenos Aires; por sus caracteres morfológicos, se encuentra en el grupo californicus, cercana a corni Haldeman, podría tratarse de una nueva especie. Asimismo, se amplía la distribución geográfica de Eretmocerus mundus Mercet, enemigo natural del complejo Bemisia tabaci (Gennadius, a las provincias de San Juan y Buenos Aires.The objective of this paper is to report new records of species of the genus Eretmocerus Haldeman, parasitoids of the most important whitefly pest species in vegetables and ornamental crops in Argentina. One species was found parasitizing Trialeurodes vaporariorum (Westwood in Santa Fe and Buenos Aires provinces and it is grouped into californicus group near corni Haldeman, due to its morphological characters. It could be a new species. The known distribution of Eretmocerus mundus Mercet, a parasitoid of Bemisia tabaci (Gennadius, is enlarged to include the provinces of San Juan and Buenos Aires of Argentina.

  6. Spiralling whitefly, Aleurodicus dispersus , a recent invader and new ...

    African Journals Online (AJOL)

    The necessity of introducing another biological control agent, the predator Nephaspis oculatus Blatchley (=amnicola Wingo) (Col., Coccinellidae), remains therefore unclear. Key Words: Biological control, Encarsia spp., Nephaspis oculatus, whitefly. Lamouche blanche, Aleurodicus dispersusRussell (Hom., Aleyrodidae) ...

  7. Occurrence of Diaretiella rapae (Mc´Intosh, 1855 (Hymenoptera: Aphidiidae Parasitising Lipaphis erysimi (Kaltenbach, 1843 and Brevicoryne brassicae (L. 1758 (Homoptera: Aphididae in Brassica napus in Mato Grosso do Sul

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    Mussury Rosilda Mara

    2002-01-01

    Full Text Available The occurrence of Diaretiella rapae parasitising Lipaphis erysimi and Brevicoryne brassicae in canola field (Brassica napus was evaluated through two sample methods in Dourados-MS. The methods, used weekly, were: entomologic sweep net and plants sacking. The aphids population was observed from initial to the senescence plant development. Aphids were more abundant during the flowering phase, and they were usually located in the stems of the inflorescence and development fruits. In this phase the largest parasitism level for D. rapae (89,7% occurred. The sample method with a sweep net captured significantly (t=4,484, P <= 0,01 more D. rapae while sacking method captured more parasitise aphids (t=2,199 with P <= 0,05 and active aphids (t=3,513, P <= 0,01.

  8. Health assessment of pine forest as affected by geothermal activities: Presence of Monterey pine aphid, Essigella californica (Essig (Homoptera: Aphidae associated with higher concentrations of boron on pine needles

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    Adolfo Arturo Del Rio Mora

    2014-06-01

    Full Text Available Studies on assessments of the air pollution and deposition caused by geothermal fields on the forest health and presence of pests have been few documented to date. In the geothermal field "Los Humeros", located between the borders of the states of Puebla and Veracruz, Mexico was realized a forest health monitoring to know the assessment could have these emissions of sulphur (S and other two chemical elements measured by their concentrations on leaf tissues in the surrounding forests. For it were evaluated the forest healthy and pest insects registered at 20 stands of which were chosen completely at random 40 trees in total/site of the species Pinus montezumae and P. teocotein natural stands and plantations and picked up leaf tissue samples representatives per stand to determine the contents of sulphur (S, boron (B and arsenic (As representing each forest stand. The results of the study revealed that the presence of forest pests are not related to the proximity of the sites to emissions from stationary sources of emissions and moreover the amount of these 3 chemical substances monitored do not have none influence on the forest healthy sites condition, except for the Monterey pine aphid Essigella californica Essig, which seems to be directly associated with higher Boron content in the needles (mean=167.47±32.15, and peak 635.46 ppm and proximity of emission sources geothermal vents or where it is believed all these chemical elements are carried down by air currents to specific points and deposited in the stands. The general model obtained and with significance of R2=56.6 and P value 0.0033 for the presence of Monterey Pine aphid and the three main pollutants released from smoke plumes in geothermal systems is [D: Essigella]= -0.2088 + 1.880E-0.5 (A:SO4+ 0.002245 (B:B + 1.248 (C:As. The results suggest the use of aphid species as bioindicators of polluted sites.

  9. Aphids (Homoptera, Aphidodea inhabiting the trees Crataegus x media Bechst. in the urban green area. Part II. Domination and frequency of aphids, their enemies and the damage caused by aphids

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    Aneta Sławińska

    2013-12-01

    Full Text Available The studies were conducted in Lublin in the years 1999-2001 in two sites (street and park ones on the trees Crataegus x inedia Bechst. The purpose was to determine the domination and frequency of particular aphid species, their effect on the decorative character of plants as well as the occurrence of the aphidophagous in aphid colonies. It was found out that A. pomi was the dominating species in both sites. The decorative character of the studied trees was lowered by aphids A. pomi and aphids from the genus Dysaphis. Aphids from the genus Dysaphis also caused changes in the chemical composition of the injured plant parts. The presence of predatory arthropods was observed in aphid colonies occurring on hawthorn. The most numerous of these were the larvae of Syrphidae and Coccinellidae. The culture of parasitized aphids gave numerous flights of parasitoids and hyperparasitoids. Greater number of both predators and parasitoids of I and II grades were observed in the street site as compared to the park site.

  10. Criterios de liberación de Encarsia formosa Gahan (Hymenoptera: Aphelinidae para el control de Trialeurodes vaporariorum (Westwood (Hemiptera: Aleyrodidae en tomate

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    Aragón Sandra

    2008-08-01

    Full Text Available

    Para la toma adecuada de decisiones en el manejo de la mosca blanca de los invernaderos, se han propuesto diferentes criterios que buscan reducir el impacto producido por el uso indiscriminado de insecticidas. Sin embargo, estos criterios de decisión son aplicables principalmente al control químico de plagas y no se conoce su uso en programas de control biológico. Por lo tanto, con este trabajo se propuso generar unos criterios de decisión para el control biológico de la mosca blanca de los invernaderos T. vaporariorum con el parasitoide Encarsia formosa, teniendo en cuenta su respuesta funcional y porcentaje de control. En un diseño completamente al azar se ubicaron 18 plantas de tomate de 8 semanas de edad infestadas con 500 ninfas de mosca blanca y 3 plantas como control absoluto. En cada planta se liberaron 0, 10, 20, 30, 40 y 50 adultos de E. formosa, con tres repeticiones por densidad. Se registró el número de ninfas melanizadas por efectos del parasitismo de E. formosa a los 12; 19 y 26 días después de la primera liberación y, al finalizar la cosecha, se realizó un conteo de las ninfas de mosca blanca totales. Los resultados de este trabajo sugieren que para obtener un control cercano a 80% se debe liberar un parasitoide por cada 17 ninfas de mosca blanca de tercer instar, evaluando el control después de 35 días. Se pueden realizar nuevas liberaciones de E. formosa dirigidas al control de las nuevas ninfas encontradas en los muestreos periódicos del cultivo.

  11. Interação entre Formigas e Aleirodídeos (Sternorrhyncha, Aleyrodidae em Cultivo Orgânico de Tangerina cv. Poncã (Citrus reticulata Blanco

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    William Rodrigues

    2011-11-01

    Abstract. The whiteflies are tending by ants, which give protection and dispersion make the control of those suckers more difficult. The interaction ant-Sternorrhyncha occurs, mainly due to the production of a sugared material named honeydew. The aim of the study as realized sampling, diversity study, frequency, constancy and dominance of the ant’s whiteflies tending species in night and day period. The sampling were conducted from October 2002 to October 2003. The species of whiteflies detected were Aleurothrixus floccosus Maskell, Aleurotrachelus cruzi Cassino, Singhiella citrifolii (Morgan and Paraleyrodes bondari Peracchi. The study concluded that 12 species of ants were associated with A. floccossus, 4 species with A. cruzi and 3 species with P. bondari. Associations between ants and S. citrifolli where not observed. Among the species of ants associated with whiteflies, those ones associated with A. floccosus presented the major diversity (0.743 and the minor dominance (0.3194 and equitability J (0.6882. Brachymyrmex sp. was the most frequent species (31.94% and also the most constant. P. bondari showed a diversity of 0.477, the dominance of 0.3333 and the equitability J 1. To A. cruzi, the diversity was of 0.422, dominance of 0.6098 e equitability J of 0.7013. This species of whiteflies show a dominance of the species Crematogaster sp. 1, with the frequency of 60.98% although it was secondary. The close relationship between A. floccosus and 12 ants demonstrates a preference for the excrements (honeydew of the whiteflies, for the quantity as well as for the quality of the honeydew.

  12. Evaluación de la transmisión del tomato yellow leaf curl virus (TYLCV-MId) en hospederas alternas cultivadas y silvestres mediante el biotipo B de mosca blanca (Bemisia tabaci (Gennadius)) (Hemiptera: Aleyrodidae)

    OpenAIRE

    Güerere Pereira, Pascual Ramón

    2013-01-01

    Durante marzo 2008 - noviembre 2009, se realizaron cuatro trabajos de investigación, el primero consistió en los análisis moleculares de muestras de tomate colectadas entre los años 2000 y 2009 provenientes de un inventario nacional de begomovirus. La extracción de ADN viral se hizo utilizando el protocolo de Gilbertson et al. (1991); para la amplificación del ADN a través de la reacción en cadena de la polimerasa (PCR) se utilizaron los siguientes pares de cebadores: AV494 - A...

  13. Oviposition behavior of the silver leaf whitefly Bemisia tabaci biotype B on tomato; Comportamento de oviposicao da mosca-branca Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) biotipo B em tomateiro

    Energy Technology Data Exchange (ETDEWEB)

    Vendramim, Jose D. [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Dept. de Entomologia, Fitopatologia e Zoologia Agricola]. E-mail: jdvendra@esalq.usp.br; Souza, Antonio P. de [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Dept. de Morfofisiologia. Lab. de Anatomia Humana]. E-mail: apsouza@nin.ufms.br; Ongarelli, Maria das G. [Universidade de Sao Paulo (USP), Piracicaba, SP (Brazil). Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Lab. de Fisiologia e Bioquimica Pos-Colheita]. E-mail: mgong@esalq.usp.br

    2009-01-15

    The objective of this work was to evaluate the influence of the leaf surface, the insect geotropic behavior and the type of foliar trichome on Bemisia tabaci (Genn.) biotype B oviposition on tomato leaves. Bemisia tabaci females were confined in acrylic boxes in which tomato leaflets were fixed at the bottom and top part of the boxes to allow insects to access the leaf surface to be tested (adaxial and/or abaxial) in both no-choice and free choice tests. Oviposition was always higher when the leaf was offered at the top of the box and preferably at the abaxial leaf surface. The effects of leaf trichomes (glandular and non glandular) on B. tabaci oviposition was evaluated by offering the abaxial surface of tomato leaflets to females after a 70% ethanol wash to remove glandular exsudates against a control treatment (without a ethanol wash). Oviposition was concentrated mostly near to non glandular trichomes, showing whitefly females can discriminate among the trichomes. (author)

  14. Biogeographic congruence in the south Pacific

    DEFF Research Database (Denmark)

    Seberg, Ole

    1991-01-01

    Zealand, Tasmania and Australia) are congruent. The area cladograms are derived from Nothofagus (Fagacae), Embothriinae (Protaceae), Oreobolus (Cyperaceae), Cyttaria (Helotiales) and Eriococcidae (Homoptera). The resulting general area cladogram showing southern South America as the sister-area to New...

  15. Evaluation de l'efficacite de quatre formulations de chlorpyriphos ...

    African Journals Online (AJOL)

    Evaluation de l'efficacite de quatre formulations de chlorpyriphos ethyl contre la cochenille Farineuse du manguier Rastrococcus invadens Williams (Homoptera : Pseudococcidae) : bilan de dix annees d'experimentation en Côte D'Ivoire.

  16. Short Communication: Occurrence of the pea aphid, Acyrthosiphon ...

    African Journals Online (AJOL)

    ) (Homoptera: Aphididae) on wild leguminous plants in West Gojam, Ethiopia. ... High plant density of vetch carried more aphid load than low plant density; sole stand of vetch plants suffered more damage than when grown mixed up with other ...

  17. Vector-virus mutualism accelerates population increase of an invasive whitefly.

    Directory of Open Access Journals (Sweden)

    Min Jiu

    Full Text Available The relationships between plant viruses, their herbivore vectors and host plants can be beneficial, neutral, or antagonistic, depending on the species involved. This variation in relationships may affect the process of biological invasion and the displacement of indigenous species by invaders when the invasive and indigenous organisms occur with niche overlap but differ in the interactions. The notorious invasive B biotype of the whitefly complex Bemisia tabaci entered China in the late 1990s and is now the predominant or only biotype in many regions of the country. Tobacco curly shoot virus (TbCSV and Tomato yellow leaf curl China virus (TYLCCNV are two whitefly-transmitted begomoviruses that have become widespread recently in south China. We compared the performance of the invasive B and indigenous ZHJ1 whitefly biotypes on healthy, TbCSV-infected and TYLCCNV-infected tobacco plants. Compared to its performance on healthy plants, the invasive B biotype increased its fecundity and longevity by 12 and 6 fold when feeding on TbCSV-infected plants, and by 18 and 7 fold when feeding on TYLCCNV-infected plants. Population density of the B biotype on TbCSV- and TYLCCNV-infected plants reached 2 and 13 times that on healthy plants respectively in 56 days. In contrast, the indigenous ZHJ1 performed similarly on healthy and virus-infected plants. Virus-infection status of the whiteflies per se of both biotypes showed limited effects on performance of vectors on cotton, a nonhost plant of the viruses. The indirect mutualism between the B biotype whitefly and these viruses via their host plants, and the apparent lack of such mutualism for the indigenous whitefly, may contribute to the ability of the B whitefly biotype to invade, the displacement of indigenous whiteflies, and the disease pandemics of the viruses associated with this vector.

  18. A Semipersistent Plant Virus Differentially Manipulates Feeding Behaviors of Different Sexes and Biotypes of Its Whitefly Vector

    Directory of Open Access Journals (Sweden)

    Shaohua Lu

    2017-01-01

    Full Text Available It is known that plant viruses can change the performance of their vectors. However, there have been no reports on whether or how a semipersistent plant virus manipulates the feeding behaviors of its whitefly vectors. Cucurbit chlorotic yellows virus (CCYV (genus Crinivirus, family Closteroviridae is an emergent plant virus in many Asian countries and is transmitted specifically by B and Q biotypes of tobacco whitefly, Bemisia tabaci (Gennadius, in a semipersistent manner. In the present study, we used electrical penetration graph (EPG technique to investigate the effect of CCYV on the feeding behaviors of B. tabaci. The results showed that CCYV altered feeding behaviors of both biotypes and sexes of B. tabaci with different degrees. CCYV had stronger effects on feeding behaviors of Q biotype than those of B biotype, by increasing duration of phloem salivation and sap ingestion, and could differentially manipulate feeding behaviors of males and females in both biotype whiteflies, with more phloem ingestion in Q biotype males and more non-phloem probing in B biotype males than their respective females. With regard to feeding behaviors related to virus transmission, these results indicated that, when carrying CCYV, B. tabaci Q biotype plays more roles than B biotype, and males make greater contribution than females.

  19. A Semipersistent Plant Virus Differentially Manipulates Feeding Behaviors of Different Sexes and Biotypes of Its Whitefly Vector

    Science.gov (United States)

    Lu, Shaohua; Li, Jingjing; Wang, Xueli; Song, Danyang; Bai, Rune; Shi, Yan; Gu, Qinsheng; Kuo, Yen-Wen; Falk, Bryce W.; Yan, Fengming

    2017-01-01

    It is known that plant viruses can change the performance of their vectors. However, there have been no reports on whether or how a semipersistent plant virus manipulates the feeding behaviors of its whitefly vectors. Cucurbit chlorotic yellows virus (CCYV) (genus Crinivirus, family Closteroviridae) is an emergent plant virus in many Asian countries and is transmitted specifically by B and Q biotypes of tobacco whitefly, Bemisia tabaci (Gennadius), in a semipersistent manner. In the present study, we used electrical penetration graph (EPG) technique to investigate the effect of CCYV on the feeding behaviors of B. tabaci. The results showed that CCYV altered feeding behaviors of both biotypes and sexes of B. tabaci with different degrees. CCYV had stronger effects on feeding behaviors of Q biotype than those of B biotype, by increasing duration of phloem salivation and sap ingestion, and could differentially manipulate feeding behaviors of males and females in both biotype whiteflies, with more phloem ingestion in Q biotype males and more non-phloem probing in B biotype males than their respective females. With regard to feeding behaviors related to virus transmission, these results indicated that, when carrying CCYV, B. tabaci Q biotype plays more roles than B biotype, and males make greater contribution than females. PMID:28098749

  20. Dynamics of Bemisia tabaci biotypes and insecticide resistance in Fujian province in China during 2005–2014

    Science.gov (United States)

    Yao, Feng-Luan; Zheng, Yu; Huang, Xiao-Yan; Ding, Xue-Ling; Zhao, Jian-Wei; Desneux, Nicolas; He, Yu-Xian; Weng, Qi-Yong

    2017-01-01

    The whitefly Bemisia tabaci (Gennadius) is an important agricultural insect pest worldwide. The B and Q biotypes are the two most predominant and devastating biotypes prevalent across China. However, there are few studies regarding the occurrence of the Q biotype in Fujian Province, China, where high insecticide resistance has been reported in the B biotype. Differences in some biological characteristics between the B and Q biotypes, especially insecticide resistance, are considered to affect the outcome of their competition. Extensive surveys in Fujian revealed that the B biotype was predominant during 2005–2014, whereas the Q biotype was first detected in some locations in 2013 and widely detected throughout the province in 2014. Resistance to neonicotinoids (that have been used for more than 10 years) exhibited fluctuations in open fields, but showed a continual increasing trend in protected areas. Resistance to lambda-cyhalothrin, chlorpyrifos, and abamectin exhibited a declining trend. Resistance to novel insecticides, such as nitenpyram, pymetrozine, sulfoxaflor, and cyantraniliprole, in 2014 was generally below a moderate level. A decline in insecticide resistance in the B biotype and the rapid buildup of protected crops under global temperature increase may have promoted the establishment of the Q biotype in Fujian. PMID:28112233

  1. Discovery of a New World ladybird beetleNephaspis indusGordon, 1996 (Coleoptera: Coccinellidae: Scymnini) on the Island of Taiwan.

    Science.gov (United States)

    Chen, Xiaosheng; Xie, Xiufeng; Ren, Shunxiang; Wang, Xingmin

    2016-01-01

    Nephaspis indus Gordon, 1996 was imported into Taiwan from Hawaii in 1990 as a biological control agent for the spiralling whitefly, Aleurodicus dispersus Russell, 1965 (Hemiptera: Aleyrodidae). However, its establishment was not known prior to this study. Nephaspis indus Gordon, 1996, a natural enemy of Aleurodicus dispersus Russell (Hemiptera: Aleyrodidae) native to the Neotropical region, is recorded as established in Taiwan for the first time. The present paper provides a detailed further description and illustrations of the adult. Diagnostic characters for the genus and species are given and the nomenclature of this species is also discussed.

  2. Genetic diversity of Bemisia tabaci (Genn. Populations in Brazil revealed by RAPD markers

    Directory of Open Access Journals (Sweden)

    L.H.C. Lima

    2002-01-01

    Full Text Available Bemisia tabaci (Genn. was considered a secondary pest in Brazil until 1990, despite being an efficient geminivirus vector in beans and soybean. In 1991, a new biotype, known as B. tabaci B biotype (=B. argentifolii was detected attacking weed plants and causing phytotoxic problems in Cucurbitaceae. Nowadays, B. tabaci is considered one of the most damaging whitefly pests in agricultural systems worldwide that transmits more than 60 different plant viruses. Little is known about the genetic variability of these populations in Brazil. Knowledge of the genetic variation within whitefly populations is necessary for their efficient control and management. The objectives of the present study were to use RAPD markers (1 to estimate the genetic diversity of B. tabaci populations, (2 to study the genetic relationships among B. tabaci biotypes and two other whitefly species and (3 to discriminate between B. tabaci biotypes. A sample of 109 B. tabaci female individuals obtained from 12 populations in Brazil were analyzed and compared to the A biotype from Arizona (USA and B biotype from California (USA and Paraguay. Trialeurodes vaporariorum and Aleurodicus cocois samples were also included. A total of 72 markers were generated by five RAPD primers and used in the analysis. All primers produced RAPD patterns that clearly distinguished the Bemisia biotypes and the two other whitefly species. Results also showed that populations of the B biotype have considerable genetic variability. An average Jaccard similarity of 0.73 was observed among the B biotype individuals analyzed. Cluster analysis demonstrated that, in general, Brazilian biotype B individuals are scattered independently in the localities where samples were collected. Nevertheless, some clusters were evident, joining individuals according to the host plants. AMOVA showed that most of the total genetic variation is found within populations (56.70%, but a significant portion of the variation is found

  3. Management of sweet potato leaf curl virus in sweetpotatoes using insecticides

    Science.gov (United States)

    Sweetpotato leaf curl virus (SPLCV), which is transmitted by the sweetpotato whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), can severely affect yields of commercial sweetpotatoes, Ipomoea batatas (L.) Lam. (Convolvulaceae). This virus occurs every year at the U.S. Vegetable Laborato...

  4. Papaya is not a host for Tomato Yellow Leaf Curl Virus

    Science.gov (United States)

    The economic value of tomato production is threatened by tomato yellow leaf-curl virus TYLCV and its vector, the silverleaf whitefly Bemisia tabaci biotype B (Gennadius) (Hemiptera: Aleyrodidae). Use of papaya Carica papaya L. as a banker plant for a whitefly parasitoid shows promise as a whitefly m...

  5. Searching and oviposition behaviour of Amitus fuscipennis, a parasitoid of the greenhouse whitefly

    NARCIS (Netherlands)

    Manzano, M.R.; Lenteren, van J.C.; Cardona, C.

    2002-01-01

    Amitus fuscipennis MacGown & Nebeker (Hym., Platygasteridae) is a parasitoid of the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hom., Aleyrodidae) on some crops as bean and snap bean ( both Phaseolus vulgaris L.) in Colombia. The searching and oviposition behaviour of A.

  6. REARING TOMATO WHITEFLY AND FIELD EVALUATION OF ...

    African Journals Online (AJOL)

    ACSS

    2015-05-27

    May 27, 2015 ... The whitefly (Bemisia tabaci(Gennadius) (Hemiptera: Aleyrodidae) is a serious pest of a wide range of economically important agricultural and ornamental crops in all agro-ecological regions in the world. This study evaluated the efficacy of conidia of entomopathogenic Beauveria bassiana (BB 315), Isaria ...

  7. Study of the pathosystem: Begomovirus Bemisia tabaci I tomato on the South West islands of the Indian Ocean

    NARCIS (Netherlands)

    Delatte, H.

    2005-01-01

    Tomato yellow leaf curl virus (TYLCV) belongs to the genus Begomovirus within the Geminiviridae family, and is exclusively transmitted by the whitefly species Bemisia labaci (Hemiptera: Aleyrodidae) (Gennadius). It is an emerging virus which since the 1980's has globally spread over many tropical,

  8. A swarm of whiteflies—the first record of gregarious behavior from Eocene Baltic amber

    Science.gov (United States)

    Szwedo, Jacek; Drohojowska, Jowita

    2016-04-01

    A new whitefly Snotra christelae gen. et sp. n. is characterized, illustrated, and described from the Baltic amber. It represents the first record of gregarious behavior of Aleyrodinae (Aleyrodidae) whiteflies in fossil state. Implications of this finding on interpretation of whiteflies and their host-plant relationships and evolutionary traits of the group are discussed.

  9. A swarm of whiteflies--the first record of gregarious behavior from Eocene Baltic amber.

    Science.gov (United States)

    Szwedo, Jacek; Drohojowska, Jowita

    2016-04-01

    A new whitefly Snotra christelae gen. et sp. n. is characterized, illustrated, and described from the Baltic amber. It represents the first record of gregarious behavior of Aleyrodinae (Aleyrodidae) whiteflies in fossil state. Implications of this finding on interpretation of whiteflies and their host-plant relationships and evolutionary traits of the group are discussed.

  10. Diversity and distribution of whiteflies in south-western Nigeria ...

    African Journals Online (AJOL)

    Whiteflies (Aleyrodidae) are major pests of crops in southwestern Nigeria, yet there is scanty information on diversity and distribution of these economic species. Therefore, a study of diversity and distribution of whitefly fauna was carried out in southwestern Nigeria in wet and dry seasons, between May 2007 and June 2012.

  11. Estimation of the whitefly Bemisia tabaci genome size based on k-mer and flow cytometry analyses

    Science.gov (United States)

    Whiteflies, Bemisia tabaci (Hemiptera: Aleyrodidae), are one of the most important agricultural insect pests in the world. These phloem-feeding insects can colonize over 500 crop plants worldwide and inflict severe economic losses, mainly through the transmission of pathogenic viruses. Surprisingl...

  12. CONTROLE QUÍMICO DA VAQUINHA (Diabrotica speciosa Germ., 1824 E DA CIGARRINHA VERDE (Empoasca kraemeri Ross & More, 1957 EM FEIJOEIRO CHEMICAL CONTROL OF BEAN LEAF BEETLE (Diabrotica speciosa GERM., 1824- COLEOPTERA: CRYSOMELLIDAE AND BEAN LEAF HOPPER (Empoasca kraemeri ROSS & MOORE, 1957-HOMOPTERA: CICADELLIDAE IN BEAN CROPS

    Directory of Open Access Journals (Sweden)

    Cláudio Aparecido Silveira

    2007-09-01

    Full Text Available

    Foi realizado o presente experimento nos campos experimentais da Escola de Agronomia da Universidade Federal de Goiás, de dezembro de 1996 a março de 1997, para o controle da vaquinha (Diabrotica speciosa e da cigarrinha verde (Empoasca kraemeri durante o ciclo da cultura com produtos aplicados via pulverizações. Os tratamentos constaram de Confidor 700 GRDA na dosagem de 0,15 kg/ha + 0,05% de Impress, Bulldock 125 SC na dosagem de 0,05 l/ha, Tamaron 600 CE na dosagem de 0,8 l/ha, Turbo 050 CE nas dosagens de 0,1 1/ha e 0,12 l/ha. Pelos resultados obtidos, concluiu-se que todos os tratamentos controlaram eficientemente a vaquinha. As porcentagens de controle variaram de 82 a 92% bem como da cigarrinha verde com porcentagens de 77 a 92%.

    PALAVRAS-CHAVE: Insecta; controle químico; feijoeiro.

    A trial to control the bean leaf beetle Diabrotica speciosa and the beanleafhopper Empoasca kraemeri was carried out in Goiânia, Goiás, Brazil. The treatments and dosage of the insecticides per hectare were: Imidacloprid (105g a.i., Betacyflutrin (5.0, 6.0 and 6.25 g a.i., Methamidophos (480 g a.i. and an untreated check. The results obtained in this experiment showed that all insecticides were efficient in controlling the bean leaf beetle and beanleafhopper in bean crops, at all dosages tested.

    KEY-WORDS: Insecta: pest control; bean crops.

  13. Indução de resistência em plantas de crisântemo pela aplicação de silício no manejo de mosca-branca Bemisia tabaci biótipo B (Hemiptera: Aleyrodidae)

    OpenAIRE

    Melo, Bruno Almeida de

    2013-01-01

    O crisântemo (Dendranthema grandiflora Tzvelev) é uma planta ornamental cultivada mundialmente, sendo no Brasil uma das principais flores de corte e vaso. A mosca-branca Bemisia tabaci (Genn) biótipo B é uma das principais pragas no cultivo do crisântemo e seu controle tem sido realizado com a aplicação de inseticidas. No entanto, a aplicação exclusiva desse método de controle pode selecionar indivíduos resistentes e, consequentemente, inviabilizar a sua utilização. Por isso, o objetivo deste...

  14. Influência do silício na indução de resistência à mosca-branca Bemisia tabaci biótipo B (Genn.) (Hemiptera:Aleyrodidae) e no desenvolvimento vegetativo em dois cultivares de soja Glycine max (I.) Merrill

    OpenAIRE

    Ferreira, Ronara de Souza

    2014-01-01

    O potencial para populações de mosca-branca se tornarem resistentes a inseticidas tem estimulado o estudo de táticas alternativas para o Manejo Integrado de Pragas, como por exemplo, a indução de resistência na planta hospedeira. Trabalhos recentes têm mostrado que o silício pode aumentar o grau de resistência da planta ao ataque de insetos. Assim sendo, os objetivos deste trabalho foram a avaliação da indução de resistência à mosca-branca B. tabaci biótipo B e o desenvolvimento vegetativo de...

  15. The effect of pesticides and aqueous extracts of Azadirachta indica ...

    African Journals Online (AJOL)

    The effect of pesticides and aqueous extracts of Azadirachta indica (A. Juss) and Jatropha carcus L. on Bemisia tabaci (Gennadius) (Homoptera: Aleyrididae) and Helicoverpa armigera (Hübner)(Lepidoptera: Noctuidae) found on tomato plants in Côte d'Ivoire.

  16. Testing Paecilomyces lilacinus , diatomaceous earth and ...

    African Journals Online (AJOL)

    Testing Paecilomyces lilacinus , diatomaceous earth and Azadirachta indica alone and in combination against cotton aphid ( Aphis gossypii Glover ) (Insecta: Homoptera: Aphididae) ... Furthermore, an increasing trend in mortality of aphids was observed in all the treatments with an increase in the time intervals. The results ...

  17. Ghana Journal of Science - Vol 36, No 1 (1996)

    African Journals Online (AJOL)

    Relationship between permethrin susceptibility and elevated esterase in clones of cotton aphid (Homoptera: Aphididae) · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. EO Owusu, F Adjei-Afriye. http://dx.doi.org/10.4314/gjs.v36i1.47993 ...

  18. Ghana Journal of Science - Vol 31 (1991)

    African Journals Online (AJOL)

    Special Food and Agriculture Edition. Log in or Register to get ... Relationship between permethrin susceptiblity and elevated esterase in clones of cotton aphid (Homoptera:Aphididae). EO Owusu, F Agyei- ... Lead concentration in food crops found along roadsides in some municipal environments in Nigeria. TJY Ideriah.

  19. African Journal of Biotechnology - Vol 11, No 4 (2012)

    African Journals Online (AJOL)

    Testing Paecilomyces lilacinus, diatomaceous earth and Azadirachta indica alone and in combination against cotton aphid (Aphis gossypii Glover) (Insecta: Homoptera: Aphididae) · EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. W Wakil, MU Ghazanfar, YJ Kwon, ...

  20. Fungal Endophytes of Wild Barley and their Effects on Diuraphis noxia Population Development

    Science.gov (United States)

    S.L. Clement; A. Dan Wilson; D.G. Lester; C.M. Davitt

    1997-01-01

    Laboratory experiments were conducted to compare the expression of Diuraphis noxia (Mordvilko) (Homoptera: Aphididae) resistance in four plant introduction (PI) lines of wild barley (Hordeum) infected with different species or strains of endophytic fungi (tribe Balansieae, family Clavicipitaceae, Neotyphodium gen. nov. [formerly...

  1. Author Details

    African Journals Online (AJOL)

    Influence Of Phytolyma lata (Homoptera: Psyllidae) On Seedling Growth Of Milicia excelsa. Abstract · Vol 26 (2010) - Articles A comparison of tree seedling growth in artificial gaps of different sizes in two contrasting forest types. Abstract · Vol 26 (2010) - Articles Wildfire incidence and management in the forest transition zone ...

  2. MUNYULI T.mdi

    African Journals Online (AJOL)

    AISA

    in Natural Sciences. CRSN-Lwiro, D. S. Bukavu, Kivu, Democratic Republic of Congo (DRC). ABSTRACT. Aphis craccivora Koch (Homoptera : Aphididae) is an economic ..... Within columns, means followed by the same letter are not significantly different at 5% probability level as determined ..... In : International Journal.

  3. Effects of charcoal production on soil biodiversity and soil physical ...

    African Journals Online (AJOL)

    ... radius around the kilns in Sudanian or Guinean savanna areas while this radius is 5 m in Semi-deciduous forest. The soil fauna assessment permitted to record 81 micro-organisms belonging essentially to the Beetles, Hymenoptera, Heteroptera, Diptera, Orthoptera, Myriapods, Homoptera, Acarians, Nematodes, Isoptera, ...

  4. Author Details

    African Journals Online (AJOL)

    Studies on some esterases of Coccinella septempunctata Brukii (Coleoptera: Coccinellidae) with varying degrees of insecticide tolerance, and implications for integrated management of aphids. Details · Vol 47 (2007) - Articles Status Of Cotton Aphid, Aphis gssypiiGlover (Homoptera: Aphididae), Resistance To Insecticides ...

  5. Author Details

    African Journals Online (AJOL)

    Lamo-Ayo, J. Vol 1, No 1 (1993) - Articles Aspects of the Biology of the Carrot Aphid Chomaphis (dysaphis) foeniculus Theobald (Homoptera: Aphididae) in Uganda Abstract PDF. ISSN: 2410-6909. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL ...

  6. Resistance to lettuce aphid (Nasonovia ribisnigri) biotype 0 in wild lettuce accessions PI 491093 and PI 274378

    Science.gov (United States)

    Lettuce aphid, Nasonovia ribisnigri Mosley (Homoptera : Aphididae), is a major insect pest of lettuce, Lactuca sativa L, in many commercial lettuce productions areas around the world. Resistance to lettuce aphid was first reported in Lactuca virosa L. accession IVT 280 and characterized as complete,...

  7. Characterization of Metarhizium anisopliae using amplifed ...

    African Journals Online (AJOL)

    edoja

    Molecular methods have revolutionized systematic entomology in the genus Metarhizium. In Brazil, the importance of these entomopathogenic fungi in agriculture is critical to the control of the sugar cane spittlebug (Mahanarva posticata) (Homoptera: Cercopidae). Other important factors for the selection of isolates of ...

  8. Author Details

    African Journals Online (AJOL)

    Adjei-Afriye, F. Vol 36, No 1 (1996): Volume 31-36; 1991-1996 - Articles Relationship between permethrin susceptibility and elevated esterase in clones of cotton aphid (Homoptera: Aphididae) Abstract. ISSN: 0855-1448. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors ...

  9. Author Details

    African Journals Online (AJOL)

    Agyei-Afriyie, F. Vol 31 (1991): Special Food and Agriculture Edition - Articles Relationship between permethrin susceptiblity and elevated esterase in clones of cotton aphid (Homoptera:Aphididae) Details. ISSN: 0855-1448. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors ...

  10. field evaluation of non-synthetic insecticides for the management of ...

    African Journals Online (AJOL)

    Preferred Customer

    mean temperature of 28.5 °C and relative humidity of 81%. The local ... before planting them directly into the soil using a dibber to the depth of ... RESULTS. Insect fauna on okra. The species of insects collected on untreated okra plants belonged to five orders namely, Coleoptera,. Heteroptera, Homoptera, Lepidoptera and.

  11. Isolation and characterization of fifteen polymorphic microsatellite ...

    Indian Academy of Sciences (India)

    la génétique des populations. Laboratoire Génome, Populations,. Interactions, CNRS UMR 5000, Université de Montpellier II,. Montpellier, France. Ben-Dov Y. 1994 A systematic catalogue of the mealybugs of the world (Insecta: Homoptera: Coccoidea: Pseudoccocidae and. Putoidae) with data on their geographical ...

  12. Extraction of differential expressing aphid-resistance genes of ...

    African Journals Online (AJOL)

    Yomi

    2012-01-03

    Jan 3, 2012 ... Key words: Extraction, sorghum, SSH, aphid-resistance genes. INTRODUCTION. Aphids (Order: Homoptera) are major insect pests of the world's agriculture which damage crops by removing photo assimilates and vectoring numerous devastating. *Corresponding author. fenglinsn@126.com,changjinhua ...

  13. Seasonality and structure of the arthropod community in a forested ...

    African Journals Online (AJOL)

    Eight groups (Araneae, Hymenoptera, Heteroptera, Homoptera, Diptera, Coleoptera, Orthoptera and Lepidoptera) made up over 95 % of all the arthropod individuals caught. There were seasonal peaks in the abundances. The highest numbers of arthropods per sample were found during the late rainy season and early dry ...

  14. Attraction of the tea aphid, toxoptera aurantii, attraction to combinations of volatiles and colors related to tea plants

    Science.gov (United States)

    The tea aphid, Toxoptera aurantii Boyer (Homoptera: Aphididae), is a major pest of the tea plant, Camellia sinensis. Fourteen volatile compounds were identified by GC-MS from air passed over intact tea shoots (ITSV). Electrophysiological and behavioral responses of the winged tea aphids to ITSV as w...

  15. Rapid spread of tomato yellow leaf curl virus in China is aided differentially by two invasive whiteflies.

    Directory of Open Access Journals (Sweden)

    Huipeng Pan

    Full Text Available BACKGROUND: Tomato yellow leaf curl virus (TYLCV was introduced into China in 2006, approximately 10 years after the introduction of an invasive whitefly, Bemisia tabaci (Genn. B biotype. Even so the distribution and prevalence of TYLCV remained limited, and the economic damage was minimal. Following the introduction of Q biotype into China in 2003, the prevalence and spread of TYLCV started to accelerate. This has lead to the hypothesis that the two biotypes might not be equally competent vectors of TYLCV. METHODOLOGY/PRINCIPAL FINDINGS: The infection frequency of TYLCV in the field-collected B. tabaci populations was investigated, the acquisition and transmission capability of TYLCV by B and Q biotypes were compared under the laboratory conditions. Analysis of B. tabaci populations from 55 field sites revealed the existence of 12 B and 43 Q biotypes across 18 provinces in China. The acquisition and transmission experiments showed that both B and Q biotypes can acquire and transmit the virus, however, Q biotype demonstrated superior acquisition and transmission capability than its B counterparts. Specifically, Q biotype acquired significantly more viral DNA than the B biotype, and reached the maximum viral load in a substantially shorter period of time. Although TYLCV was shown to be transmitted horizontally by both biotypes, Q biotype exhibited significantly higher viral transmission frequency than B biotype. Vertical transmission result, on the other hand, indicated that TYLCV DNA can be detected in eggs and nymphs, but not in pupae and adults of the first generation progeny. CONCLUSIONS/SIGNIFICANCE: These combined results suggested that the epidemiology of TYLCV was aided differentially by the two invasive whiteflies (B and Q biotypes through horizontal but not vertical transmission of the virus. This is consistent with the concomitant eruption of TYLCV in tomato fields following the recent rapid invasion of Q biotype whitefly in China.

  16. Extraordinary resistance to insecticides reveals exotic Q biotype of Bemisia tabaci in the New World.

    Science.gov (United States)

    Dennehy, Timothy J; Degain, Benjamin A; Harpold, Virginia S; Zaborac, Marni; Morin, Shai; Fabrick, Jeffrey A; Nichols, Robert L; Brown, Judith K; Byrne, Frank J; Li, Xianchun

    2010-12-01

    A strain of the whitefly Bemisia tabaci (Gennadius) possessing unusually high levels of resistance to a wide range of insecticides was discovered in 2004 in the course of routine resistance monitoring in Arizona. The multiply resistant insects, collected from poinsettia (Euphorbia pulcherrima Willd. ex Klotzsch) plants purchased at a retail store in Tucson, were subjected to biotype analysis in three laboratories. Polyacrylamide gel electrophoresis of naphthyl esterases and sequencing of the mitochondrial cytochrome oxidase I gene (780 bp) confirmed the first detection of the Q biotype of B. tabaci in the New World. This U.S. Q biotype strain, referred to as Poinsettia'04, was highly resistant to two selective insect growth regulators, pyriproxyfen and buprofezin, and to mixtures of fenpropathrin and acephate. It was also unusually low in susceptibility to the neonicotinoid insecticides imidacloprid, acetamiprid, and thiamethoxam, relative to B biotype whiteflies. In 100 collections of whiteflies made in Arizona cotton (Gossypium spp.), vegetable, and melon (Cucumis melo L.) fields from 2001 to 2005, no Q biotypes were detected. Regions of the United States that were severely impacted by the introduction of the B biotype of B. tabaci in the 1980s would be well advised to promote measures that limit movement of the Q biotype from controlled environments into field systems and to formulate alternatives for managing this multiply-resistant biotype, in the event that it becomes more widely distributed.

  17. Biotype and insecticide resistance status of the whitefly Bemisia tabaci from China.

    Science.gov (United States)

    Wang, Zhenyu; Yan, Haifei; Yang, Yihua; Wu, Yidong

    2010-12-01

    Resistance to numerous insecticide classes in Bemisia tabaci Gennadius has impaired field control efficacy in south-eastern China. The biotype and resistance status of B. tabaci collected from these areas was investigated. Two different biotypes of B. tabaci (B-biotype and Q-biotype) were detected in south-eastern China, and the samples collected from geographical regions showed a prevalence of the Q-biotype and the coexistence of B- and Q-biotypes in some regions. Moderate to high levels of resistance to two neonicotinoids were established in both biotypes (28-1900-fold to imidacloprid, 29-1200-fold to thiamethoxam). Medium to high levels of resistance to alpha-cypermethrin (22-610-fold) were also detected in both biotypes. Four out of 12 populations had low to medium levels of resistance to fipronil (10-25-fold). Four out of 12 populations showed low levels of resistance to spinosad (5.7-6.4-fold). All populations tested were susceptible to abamectin. The Q-biotype B. tabaci is supplanting the B-biotype which used to be ubiquitous in China. Field populations of both B- and Q-biotypes of B. tabaci have developed high levels of resistance to imidacloprid and thiamethoxam. Abamectin is the most effective insecticide against adult B. tabaci from all populations. Copyright © 2010 Society of Chemical Industry.

  18. New Insecticides for Management of Tomato Yellow Leaf Curl, a Virus Vectored by the Silverleaf Whitefly, Bemisia tabaci

    OpenAIRE

    Smith, H. A.; Giurcanu, M. C.

    2014-01-01

    Greenhouse studies using a randomized complete block design were carried out to evaluate the effect of six insecticides on transmission of Tomato yellow leaf curl virus (TYLCV) by the silverleaf whitefly, Bemisia tabaci biotype B Gennadius (Hemiptera: Aleyrodidae) to tomato, Lycopersicon esculentum (Miller) (Solanales: Solanaceae), seedlings that were inoculated with whiteflies from a TYLCV colony in cages 3, 7, or 14?d after treatment with insecticide. The purpose was to reveal differences i...

  19. Effect of solid and aqueous extract of vermicompost on growth characteristics of tomato and greenhouse whitefly (Trialeurodes vaporariorum)

    OpenAIRE

    A. Peimani Foroushani; N. Poorjavad; M. Haghigh; J. Khajehali

    2016-01-01

    Considering the increase of using vermicompost fertilizers in greenhouse cultivation, effect of vermicompost application on growth characteristics of tomato and one of its major pests [greenhouse whitefly, Trialeurodes vaporariorum (Hem:Aleyrodidae)] was investigated. The experiment consisted of five treatments: control (without vermicompost), 30% and 60% solid vermicompost fertilizer, and 40% and 20% aqueous extracts of vermicompost. Effect of vermicompost on greenhouse whitefly was tested f...

  20. Shrub-inhabiting insects of the 200 Area Plateau, southcentral Washington.

    Energy Technology Data Exchange (ETDEWEB)

    Rogers, L.E.

    1979-10-01

    This study characterizes the insects (including spiders) associated with major shrubs of the 200 Area Plateau on the Hanford Site in southcentral Washington. Big sagebrush (Artemisia tridentata), rabbitbrush (Chrysothamnus sp.) and hopsage (Grayia spinosa) were the three shrubs included in the study. Hemiptera (true bugs) and homoptera (bugs) were the two groups most abundant on sagebrush. Homoptera and Araneida (spiders) were the common inhabitants of rabbitbrush, and Orthoptera (grasshoppers), Coleoptera (beetles), and Araneida the taxa most frequently collected from hopsage. A discussion of the effects of insects on western native shrubs is included. None of the insect populations appeared to threaten the stability of shrub stands, which is important because of the erodability of 200 Area soils.

  1. Description and biological features of a new species of Anagrus Haliday (Hymenoptera, Mymaridae

    Directory of Open Access Journals (Sweden)

    F. Nugnes

    2014-04-01

    Full Text Available Anagrus lindberginae sp. n. (Hymenoptera: Mymaridae, an egg par- asitoid of the leafhopper Lindbergina aurovittata (Homoptera: Cicadellidae, is described from Italy. It is included in the atomus group of Anagrus Haliday and compared with the allied known taxa. The parasitoid’s life cycle is characterized by a long larval diapause from spring to fall, which allows for synchronization with its leafhop- per host; other biological traits of A. lindberginae on the evergreen plant Quercus ilex are discussed.

  2. Evaluation du potentiel insecticide de l'huile essentielle de Ocimum ...

    African Journals Online (AJOL)

    Evaluation du potentiel insecticide de l'huile essentielle de Ocimum canum Sims sur Aphis gossypii Glover (Homoptera : Aphididae) au Togo. ... Les tests biologiques ont été effectués en laboratoire selon la méthodologie Insecticide Resistance Action Commitee (IRAC) N° 1 Version 2. Les résultats de ces tests ont révélé ...

  3. A molecular phylogeny of Hemiptera inferred from mitochondrial genome sequences.

    Science.gov (United States)

    Song, Nan; Liang, Ai-Ping; Bu, Cui-Ping

    2012-01-01

    Classically, Hemiptera is comprised of two suborders: Homoptera and Heteroptera. Homoptera includes Cicadomorpha, Fulgoromorpha and Sternorrhyncha. However, according to previous molecular phylogenetic studies based on 18S rDNA, Fulgoromorpha has a closer relationship to Heteroptera than to other hemipterans, leaving Homoptera as paraphyletic. Therefore, the position of Fulgoromorpha is important for studying phylogenetic structure of Hemiptera. We inferred the evolutionary affiliations of twenty-five superfamilies of Hemiptera using mitochondrial protein-coding genes and rRNAs. We sequenced three mitogenomes, from Pyrops candelaria, Lycorma delicatula and Ricania marginalis, representing two additional families in Fulgoromorpha. Pyrops and Lycorma are representatives of an additional major family Fulgoridae in Fulgoromorpha, whereas Ricania is a second representative of the highly derived clade Ricaniidae. The organization and size of these mitogenomes are similar to those of the sequenced fulgoroid species. Our consensus phylogeny of Hemiptera largely supported the relationships (((Fulgoromorpha,Sternorrhyncha),Cicadomorpha),Heteroptera), and thus supported the classic phylogeny of Hemiptera. Selection of optimal evolutionary models (exclusion and inclusion of two rRNA genes or of third codon positions of protein-coding genes) demonstrated that rapidly evolving and saturated sites should be removed from the analyses.

  4. A molecular phylogeny of Hemiptera inferred from mitochondrial genome sequences.

    Directory of Open Access Journals (Sweden)

    Nan Song

    Full Text Available Classically, Hemiptera is comprised of two suborders: Homoptera and Heteroptera. Homoptera includes Cicadomorpha, Fulgoromorpha and Sternorrhyncha. However, according to previous molecular phylogenetic studies based on 18S rDNA, Fulgoromorpha has a closer relationship to Heteroptera than to other hemipterans, leaving Homoptera as paraphyletic. Therefore, the position of Fulgoromorpha is important for studying phylogenetic structure of Hemiptera. We inferred the evolutionary affiliations of twenty-five superfamilies of Hemiptera using mitochondrial protein-coding genes and rRNAs. We sequenced three mitogenomes, from Pyrops candelaria, Lycorma delicatula and Ricania marginalis, representing two additional families in Fulgoromorpha. Pyrops and Lycorma are representatives of an additional major family Fulgoridae in Fulgoromorpha, whereas Ricania is a second representative of the highly derived clade Ricaniidae. The organization and size of these mitogenomes are similar to those of the sequenced fulgoroid species. Our consensus phylogeny of Hemiptera largely supported the relationships (((Fulgoromorpha,Sternorrhyncha,Cicadomorpha,Heteroptera, and thus supported the classic phylogeny of Hemiptera. Selection of optimal evolutionary models (exclusion and inclusion of two rRNA genes or of third codon positions of protein-coding genes demonstrated that rapidly evolving and saturated sites should be removed from the analyses.

  5. Indigenous American species of the Bemisia tabaci complex are still widespread in the Americas.

    Science.gov (United States)

    Barbosa, Leonardo da F; Marubayashi, Julio M; De Marchi, Bruno R; Yuki, Valdir A; Pavan, Marcelo A; Moriones, Enrique; Navas-Castillo, Jesús; Krause-Sakate, Renate

    2014-10-01

    Bemisia tabaci is a complex of at least 36 putative cryptic species. Since the late 1980s, the Middle East-Asia Minor 1 species (MEAM1, formerly known as the B biotype), has emerged in many tropical and subtropical regions of the world and in some areas has displaced the indigenous populations of B. tabaci. Based on analysis of the mtCOI gene, two indigenous species native to America have been reported: New World (NW, formerly the A biotype) and New World 2 (NW2). NW is present at least in Argentina, Brazil, Martinique, Mexico, Texas and Venezuela, and NW2 in Argentina, Bolivia and Brazil. Wild plants (Euphorbia sp. and Ipomoea sp.), as well as important crops such as tomato, bean and cotton, are still hosts for native B. tabaci populations in the Americas. MEAM1 has not completely displaced the native B. tabaci from the Americas. © 2014 Society of Chemical Industry.

  6. Compatibilidad in vitro de isaria fumosorosea (wize) brown y smith (hypocreales: clavicipitaceae) con plaguicidas comerciales

    OpenAIRE

    Érika Paola Grijalba Bernal; Martha Isabel Gómez Álvarez; María Victoria Zuluaga Mogollón

    2014-01-01

    Los agricultores colombianos utilizan productos químicos con categorías toxicológicas I, II y III para el control de insectos como la mosca blanca Bemisia tabaci (Gennadius, 1889) (Hemiptera: Aleyrodidae); pero su uso indiscriminado genera un riesgo para la salud y el medio ambiente. El control microbiológico con hongos entomopatógenos surge como alternativa de control ambientalmente sostenible. No obstante, su empleo exitoso dentro de una estrategia de manejo integrado de plagas (MIP) depe...

  7. Update on the Status of Bemisia tabaci in the UK and the Use of Entomopathogenic Fungi within Eradication Programmes

    Directory of Open Access Journals (Sweden)

    Andrew G. S. Cuthbertson

    2013-05-01

    Full Text Available The sweetpotato whitefly Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae continues to be a serious threat to crops worldwide. The UK holds Protected Zone status against this pest and, as a result, B. tabaci entering on plant material is subjected to a policy of eradication. Both B and Q Bemisia biotypes are now regularly intercepted entering the UK. With increasing reports of neonicotinoid resistance in both these biotypes, it is becoming more problematic to control/eradicate. Therefore, alternative means of control are necessary. Entomopathogenic fungi (Lecanicilllium muscarium and Beauveria bassiana offer much potential as control agents of B. tabaci within eradication programmes in the UK.

  8. Update on the Status of Bemisia tabaci in the UK and the Use of Entomopathogenic Fungi within Eradication Programmes

    Science.gov (United States)

    Cuthbertson, Andrew G. S.

    2013-01-01

    The sweetpotato whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) continues to be a serious threat to crops worldwide. The UK holds Protected Zone status against this pest and, as a result, B. tabaci entering on plant material is subjected to a policy of eradication. Both B and Q Bemisia biotypes are now regularly intercepted entering the UK. With increasing reports of neonicotinoid resistance in both these biotypes, it is becoming more problematic to control/eradicate. Therefore, alternative means of control are necessary. Entomopathogenic fungi (Lecanicilllium muscarium and Beauveria bassiana) offer much potential as control agents of B. tabaci within eradication programmes in the UK. PMID:26464385

  9. Biodiversidad antropoentomofágica de la región de Zongolica, Veracruz, México

    OpenAIRE

    Julieta Ramos-Elorduy; Ivonne Landero-Torres; Joaquín Murguía-González; José M Pino M

    2006-01-01

    Durante dos años y medio (2003-2005) se rastrearon a los insectos que se ingieren en el área de Zongolica, Veracruz: para ello se entrevistó a la gente de ese municipio (200), para conocer cuáles especies ingerían. El total de especies registradas, ascendió a 57 distribuidas en los órdenes Orthoptera, Hemiptera, Homoptera, Megaloptera, Coleoptera, Lepidoptera e Hymenoptera, correspondiendo el mayor consumo al primer orden. De las especies registradas, 24 son nuevos registros de insectos comes...

  10. Diet of two sympatric insectivores bats (Chiroptera: Vespertilionidae in the Cerrado of Central Brazil Dieta de duas espécies simpátricas de morcegos insetívoros no Cerrado do Brasil Central

    Directory of Open Access Journals (Sweden)

    Ludmilla M. S. Aguiar

    2008-03-01

    Full Text Available We examined food habits of Vespertilionidae bats Myotis nigricans (Schinz, 1821 and Eptesicus furinalis (d'Orbigny, 1847 by fecal analysis in cerrado sensu stricto and gallery forests, within APA - Gama-Cabeça-de-Veado, Brasília, Distrito Federal, Brazil. Out of 20 fecal samples collected, seven were of Eptesicus furinalis and 13 of Myotis nigricans. The diet of E. furinalis included six orders of insects: Coleoptera (5/7 by items presence, Lepidoptera and Hymenoptera (3/7, Diptera, Hemiptera and Homoptera (1/7. The diet of M. nigricans included all the main orders consumed by E. furinalis (6/13, 4/13, 4/13, 3/13, 1/13, and 4/13 respectively and one other order: Orthoptera (1/13. Homoptera, Diptera and Orthoptera were collected only in bats captured in gallery forest. There is 80% of overlap in the diet of these two species. Predation on species of Scarabeidae, Hesperiidae, Sphingidae and Saturniidae families confirms bats potential as biological control agents of pests in agricultural ecosystems.Foi examinado o hábito alimentar das espécies de Vespertilionidae Myotis nigricans (Schinz, 1821 e Eptesicus furinalis (d'Orbigny, 1847 por meio de análise de amostras fecais coletadas em animais capturados em área de cerrado sensu stricto e matas de galeria, na APA - Gama-Cabeça-de-Veado, Brasília, Distrito Federal, Brasil. Um total de 20 amostras fecais foi analisado, sendo sete de E. furinalis e 13 de M. nigricans. A dieta de E. furinalis incluiu seis ordens de insetos: Coleoptera (5/7 (presença na amostra total, Lepidoptera e Hymenoptera (3/7, Diptera, Hemiptera e Homoptera (1/7. A dieta de M. nigricans incluiu todas as ordens consumidas por E. furinalis (6/13, 4/13, 4/13, 3/13, 1/13, and 4/13 respectively e uma ordem a mais: Orthoptera (1/13. Homoptera, Diptera e Orthoptera só foram amostrados para morcegos capturados em mata de galeria. Há 80% de sobreposição na dieta destas duas espécies. A predação sobre espécies das fam

  11. [Research progress on medicinal resources of Mylabris and close origin species].

    Science.gov (United States)

    Zhang, Jianhui; Chen, Jianwei; Li, Xiang

    2009-03-01

    The paper summarizes the research progress on the medicinal resources of Mylabris and close origin species in recent years. Besides the 45 species in 7 genus within Meloidae insects which contain cantharidin, there are also more 9 species in 7 close origin genus containing cantharidin which include Zanna, Fulgora and Lycorma within Fulgoridae of Homoptera, Oxocopis, Heliocis Xanthochroa and Oedemera within Oedemeridae of Coleoptera. New medicinal resources of cantharidin are redundant, there are biological relationships in the biosynthesis of cantharidin, the emerge of cantharidin is related to ecology and there is more attention on the new methods of utilizing Mylabris resources such as living body extraction.

  12. Final Environmental Impact Statement. Permit Application by United States Steel Corp., Proposed Lake Front Steel Mill, Conneaut, Ohio. Volume 2.

    Science.gov (United States)

    1979-01-01

    Springfield, and narrowest in Fairview and 2-647 A’. . .. . L"’ [I owMidnl of Looalurs~cin a-r ;n~.k I3Ii 0 to~ 4L~J~j EIIJFIIr POOR % dna So(e: G...ing ants and grasshoppers . At Area No. 5, the youngest successional stage, Chrysomelidae beetle larvae, plant bugs (Hemiptera and Cicadellidae) and...leaf hoppers (Homoptera) were most abundant during mid-summer while grasshoppers (Orthoptera) were numerous during the autumn. The shrublands of Area No

  13. Resposta de fêmeas de Encarsia formosa Gahan (Hymenoptera: Aphelinidae aos odores do hospedeiro e da planta-hospedeira em olfatômetro de quatro vias Response of female Encarsia formosa Gahan (Hymenoptera: Aphelinidae to host and plant-host odors

    Directory of Open Access Journals (Sweden)

    Kátia Maria Medeiros de Siqueira

    2003-01-01

    Full Text Available A crescente importância da mosca-branca Bemisia tabaci raça B (Hemiptera: Aleyrodidae como praga agrícola tem incentivado a busca de inimigos naturais que possam ser utilizados em programas de controle biológico. Estudou-se a atração de fêmeas de Encarsia formosa (Hymenoptera: Aphelinidae aos odores emanados pelo seu hospedeiro - a mosca-branca B. tabaci raça B - em plantas de tomate, em olfatômetro de quatro vias. O parasitóide não apresentou atração aos odores da planta de tomate nem ao complexo planta de tomate-ninfas de B. tabaci.The increasing importance of the whitefly Bemisia tabaci race B (Hemiptera: Aleyrodidae as one of the major agricultural pest of this century, has resulted in a search for natural enemies that can be used in biological control programs. The response of naive females of Encarsia formosa (Hymenoptera: Aphelinidaeto volatiles from its hostspecies: insect (B. tabacci race B and plant (Lycopersicom esculentum Mill. were tested using 4-nose olfactometre. Parasitoid was not attracted by neither or insect hostspecies volatile.

  14. Población de mosca blanca en tomate cultivado a campo con pantallas de sombreamiento Whitefly population in shaded tomato field

    Directory of Open Access Journals (Sweden)

    Daniel Sánchez

    2005-02-01

    Full Text Available El objetivo de este trabajo fue analizar la población de mosca blanca Trialeurodes vaporariorum, Westwood (Hemiptera: Aleyrodidae en tomate de verano en cultivos con sombreado, en Santa Fe, Argentina. Se transplantó tomate en hileras cubriendo un sector con malla negra de polipropileno, realizándose cada tres días, en 30 plantas un recuento de adultos en una hoja superior y de ninfas en diez folíolos al azar. El diseño experimental fue de bloques al azar analizándose la correlación entre la temperatura y la evolución de adultos y ninfas. El sombreado disminuyó la temperatura, pero incrementó diez veces la densidad de adultos y cinco veces la de ninfas respecto al cultivo al aire libre.In Santa Fe, Argentina, whitefly (Trialeurodes vaporariorum, Westowood (Hemiptera: Aleyrodidae populations were monitored during summer in shaded and non shaded tomato field. Tomato was transplanted in rows and half of crop surface was shaded with a black polypropilen layer. Whitefly population was monitored at three-day intervals in 30 plants. Adult whiteflies were surveyed in the highest developed leaf and immature stages in 10 random leaflets in each plant. Experimental design was in randomized blocks and the correlation was calculated among temperature and number of adults and nymphs. In shaded tomato, temperature was lower but whitefly adult populations increased ten times and immature stages increased five times.

  15. Contribution to the study of insects (Arthropoda:Insecta associated with the genus Ixora L. (Angiospermae: Rubiaceae in Brazil

    Directory of Open Access Journals (Sweden)

    Thiago Dias Trindade

    2015-08-01

    Full Text Available This study aimed to register insects (Arthropoda: Insecta associated with genus Ixora L. (Angiospermae: Rubiaceae and contribute the knowledge about this popular tropical ornamental plant in Brazil. For this study, we detected the presence of insects in solid or isolated plants of Ixora spp., and greenhouses, between the period 2004 and 2012. It was pointed out for the first time on I. chinensis Lam.: Syntermes dirus (Burmeister, 1839 (Isoptera: Termitidae, Aspidiotus destructor (Signoret, 1869 and Chrysomphalus aonidum (Linnaeus, 1758 (Hemiptera: Diaspididae, Praelongorthezia praelonga (Douglas, 1891 (Hemiptera: Ortheziidae and Camponotus sp. (Hymenoptera: Formicidae. Studies registered for the first time on I. coccinea L.: Aleurothrixus aepim (Goeldi, 1886 and Bemisia tabaci (Gennadius, 1889 (Hemiptera: Aleyrodidae Eucalymnatus sp., Parasaissetia nigra (Nietner, 1861 and Saissetia olae (Olivier, 1791 (Hemiptera: Coccidae, and Camponotus sp. It was observed first on I. macrothyrsa Teijsm. & Binn. N. E. Br.: Aleurothrixus floccosus (Maskell, 1895, Aleurotrachelus sp. (Aleyrodidae, Aphis (Toxoptera citricida (Kirkaldy, 1907 and Myzus (Nectarosiphon persicae (Sulzer, 1778 (Hemiptera: Aphididae Harmonia sp. (Coleoptera: Coccinellidae, Camponotus sp. This paper contributes to the study of these important ornamental plants, presenting for the first time a list of associated insects. This work also creates conditions for future studies.

  16. Pengendalian Hayati Afid pada Tanaman Cabai Merah dengan Menochilus sexmaculatus

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    Dahlia Simanjuntak

    2011-12-01

    Full Text Available A field trial on biological control of aphids (Homoptera: Aphididae with Menochilus sexmaculatus (Coleoptera: Coccinellidae was conducted at red chilli field in Sleman, Yogyakarta, in the planting season of 2010. Second instar was released at rate of 1 larva/250 aphids. The number of predator per plant varied depending on aphid-population density. The effectiveness of the predator was compared with application of sihalotrin 25 g/l at concentration rate of 2 cc/l as much as 500 l/ha. The results showed that effectiveness of the predator application was equal with the insecticide application.   Percobaan lapangan pengendalian hayati Aphis spp. (Homoptera: Aphididae dengan Menochilus sexmaculatus (Coleoptera: Coccinellidae dilakukan di lahan cabai merah di daerah Sleman, Yogyakarta, pada musim tanam tahun 2010. Satu ekor larva instar II dilepas pada populasi 250 ekor afid. Banyaknya predator per tanaman bervariasi tergantung kepadatan populasi afid. Keefektifan aplikasi predator dibandingkan dengan perlakuan sihalotrin 25 g/l, konsentrasi 2 cc/l sebanyak 500 l/ha. Hasil kajian menunjukkan bahwa keefektifan aplikasi predator setara dengan aplikasi insektisida

  17. Biotype expression and insecticide response of Bemisia tabaci chemosensory protein-1.

    Science.gov (United States)

    Liu, Guo Xia; Xuan, Ning; Chu, Dong; Xie, Hong Yan; Fan, Zhong Xue; Bi, Yu Ping; Picimbon, Jean-François; Qin, Yu Chuan; Zhong, Su Ting; Li, Yao Fa; Gao, Zhan Lin; Pan, Wen Liang; Wang, Guo Ying; Rajashekar, Balaji

    2014-03-01

    Chemosensory proteins (CSPs) are a group of small soluble proteins found so far exclusively in arthropod species. These proteins act in chemical communication and perception. In this study, a gene encoding the Type 1 CSP (BtabCSP1) from the agricultural pest Bemisia tabaci (whitefly) was analyzed to understand sequence variation and expression specificity in different biotypes. Sequence analysis of BtabCSP1 showed significant differences between the two genetically characterized biotypes, B and Q. The B-biotype had a larger number of BtabCSP1 mutations than the Q-biotype. Similar to most other CSPs, BtabCSP1 was more expressed in the head than in the rest of the body. One-step RT-PCR and qPCR analysis on total messenger RNA showed that biotype-Q had higher BtabCSP1 expression levels than biotype-B. Females from a mixed field-population had high levels of BtabCSP1 expression. The interaction of BtabCSP1 with the insecticide thiamethoxam was investigated by analyzing the BtabCSP1 expression levels following exposure to the neonicotinoid, thiamethoxam, in a time/dose-response study. Insecticide exposure increased BtabCSP1 expression (up to tenfold) at 4 and 24 h following 50 or 100 g/ml treatments. © 2014 Wiley Periodicals, Inc.

  18. Single basal application of thiacloprid for the integrated management of Meloidogyne incognita and Bemisia tabaci in tomato crops

    Science.gov (United States)

    Dong, Sa; Ren, Xiaofen; Zhang, Dianli; Ji, Xiaoxue; Wang, Kaiyun; Qiao, Kang

    2017-01-01

    Tomato growers commonly face heavy nematode (Meloidogyne incognita) and whitefly (B-biotype Bemisia tabaci) infestations, and previous studies demonstrated that thiacloprid could be used to control M. incognita and B. tabaci in cucumber. However, the efficacy of a single basal application of thiacloprid to control both pests and its effect on yield in tomato remains unknown. In this study, the potential of thiacloprid application to the soil for the integrated control of M. incognita and B. tabaci in tomato was evaluated in the laboratory and the field. Laboratory tests showed that thiacloprid was highly toxic to whitefly adults and eggs with an average lethal concentration 50 (LC50) of 14.7 and 62.2 mg ai L-1, respectively, and the LC50 of thiacloprid for nematode J2s and eggs averaged 36.2 and 70.4 mg ai L-1, respectively. In field trials, when thiacloprid was applied to the soil at 7.5, 15 and 30 kg ha-1 in two consecutive years, whitefly adults decreased by 37.8-75.4% within 60 days of treatment, and the root-galling index was reduced by 31.8-85.2%. Optimum tomato plant growth and maximum yields were observed in the 15 kg ha-1 treatment. The results indicated that a single basal application of thiacloprid could control M. incognita and B. tabaci and enhance tomato growth and yield.

  19. DESENVOLVIMENTO E CAPACIDADE DE CONSUMO DE Chrysoperla externa (Hagen, 1861 ALIMENTADA COM NINFAS DE MOSCA-BRANCA CRIADAS EM HORTALIÇAS

    Directory of Open Access Journals (Sweden)

    ELISA ADRIANO

    2010-01-01

    Full Text Available Many arthropods are mentioned with whitefly natural enemies, including the green lacewings. The aim of this study is to analyses the development and the capacity of predation of Chrysoperla externa (Hagen, 1861 fed with Bemisia tabaci B biotype nymphs, rearing different vegetables (kale, broccoli, eggplant end tomato. The duration, viability end weight in each stage end phase of development of the insectpredator had been evaluated, as well as the predatory capacity of the larvae in the third instar. The larval phase of the predator presented minor duration when these had been fed with nymphs developed the broccoli (12.36 days and minor duration of the tomato (14.36 days phase when fed with nymphs developed in kale, broccoli, and eggplant (6.50, 7.20, 7.33 days, respectively. The lower indices of viability been found for the larvae fed with nymphs developed in the tomato (30%, and average weights have. The predatory capacity of the larvae during the third instar was not affected, independently on the plant host where the whitefly nymph fed itself.

  20. Microbial control of the invasive spiraling whitefly on cassava with entomopathogenic fungi.

    Science.gov (United States)

    Boopathi, Thangavel; Karuppuchamy, Palaniappan; Singh, Soibam B; Kalyanasundaram, Manickavasagam; Mohankumar, S; Ravi, Madhaiyan

    2015-01-01

    The entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae, Lecanicillium lecanii and Isaria fumosorosea were tested for their efficacy in managing the exotic spiraling whitefly Aleurodicus dispersus (Hemiptera, Aleyrodidae) on cassava (Manihot esculenta) during 2 seasons (2011-2012 and 2012-2013). The fungi I. fumosorosea and L. lecanii exhibited promising levels of control (> 70% mortality of the A. dispersus population). The percent mortality increased over time in both seasons. Application of I. fumosorosea was highly pathogenic to A. dispersus in both seasons compared to the other entomopathogenic fungi. Analysis of the percent mortality in both seasons revealed differences in efficacy between 3 and 15 days after treatment. The season also influenced the effects of the fungi on the A. dispersus population. Thus, entomopathogenic fungi have the potential to manage A. dispersus infestation of cassava.

  1. Preferência de Bemisia tabaci biótipo B em linhagens mutantes de algodoeiro Bemisia tabaci biotype B preference in mutant cotton lines

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    Francisco das Chagas Vidal Neto

    2008-02-01

    Full Text Available Os efeitos de caracteres mutantes morfológicos do algodoeiro (Gossypium hirsutum L. r. latifolium Hutch.: folha okra, bráctea frego e planta vermelha, em relação à resistência à mosca-branca (Bemisia tabaci biótipo B Hemiptera: Aleyrodidae, foram avaliados em experimentos com ou sem chance de escolha. Os experimentos foram conduzidos em casa-de-vegetação, no delineamento de blocos ao acaso, em fatorial 23 + 1, com quatro repetições. O mutante com a característica planta vermelha foi menos atrativo e menos preferido para oviposição, em relação à planta verde, em ambos os ensaios, com ou sem escolha. Não houve preferência quanto à forma da folha e ao tipo de bráctea.The effects of cotton lines (Gossypium hirsutum L. r. latifolium Hutch. with mutants morphologic characteristics: okra leaf, frego bract and red plant in relation to host plant resistance to whitefly (Bemisia tabaci bioyipe B Hemiptera: Aleyrodidae, were evaluated in choice or no choice assays. The assays were carried out in the greenhouse conditions, according to a completely randomized block design, in a 23 + 1 in a factorial arrangement with four replications. The mutant with red plant characteristic was less attractive and less preferred for oviposition than the normal green plant does, in both, whit or without choice tests. It did not have preference in relation to the form of the leaf and bract type.

  2. Foraging, Mating, and Thermoregulatory Behavior of Cyrtopogon willistoni Curran (Diptera: Asilidae

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    Kevin M. O'Neill

    1995-01-01

    Full Text Available The robber fly Cyrtopogon willistoni Curran was studied in SW Montana, where it was an opportunistic predator of relatively small insects from 25 families in 7 orders. The most common prey were Diptera (44% and Homoptera (21%, with Cicadellidae, Bibionidae, and Formicidae comprising 44% of the prey. The elaborate courtship behavior of males included audible airborne visual displays that made use of silvery-white combs of hairs on the males' foretarsi. While perching, the flies exhibited both lateral and dorsal basking postures, and were apparently capable of strong flight only when direct sunlight was available. I compare the foraging and courtship behaviors of C. willistoni to those of other Cyrtopogon, and their thermal responses to those of other robber flies in the same habitat.

  3. Embryonic development of pleuropodia of the cicada, Magicicada cassini.

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    Strauss, Johannes; Lakes-Harlan, Reinhard

    2006-01-01

    In many insects the first abdominal segment possesses embryonic appendages called pleuropodia. Here we show the embryogenesis of pleuropodial cells of the periodical cicada, Magicicada cassini (Fisher 1851) (Insecta, Homoptera, Cicadidae). An antibody, anti-horseradish perioxidase (HRP), that is usually neuron-specific strongly marked the pleuropodial anlagen and revealed their ectodermal origin shortly after limb bud formation. Thereafter the cells sank into the epidermis and their apical parts enlarged. A globular part protruded from the body wall. Filamentous structures were marked at the stem region and into the apical dilation. In later embryonic stages the pleuropodia degenerated. Despite the binding of anti-HRP the cells had no morphological neuronal characters and cannot be regarded as neurons. The binding indicates that glycosylated cell surface molecules contribute to the adhesion between the presumably glandular pleuropodial cells. In comparison, anti-HRP does not mark the pleuropodia of Orthoptera.

  4. Field Evaluation of Three Entomopathogenic fungi on Groundnut Pest

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    Sahayaraj, K.

    2011-01-01

    Full Text Available Entomopathogenic fungi Beauveria bassiana (Balsamo Vuillemin (Deuteromycotina: Hyphomycetes, Paecilomyces fumosoroseus (Wize (Deuteromycotina: Hyphomycetes, Verticillium lecani Viegas (Deuteromycotina: Hyphomycetes were tested against groundnut pests, Aphis craccivora (Koch (Homoptera: Aphididae, Aproarema modicella (Deventer (Lepidoptera: Gelechiidae, Mylabris pustulata Faust (Coleoptera: Meloidae and Spodoptera litura (Fabricius (Lepidoptera: Noctuidae in field conditions. Among the tested fungi, V. lecanii suppressed 62% of A. craccivora population at 39 Days After Seedling Emergence (DASE. During the same period, B. bassiana reduced 72% of S. litura larval population (0.73 larvae. The infestation of S. litura and A. modicella were greatly reduced after the treatment of B. bassiana; subsequently the yield (1721.31 kg/ha-1 and cost benefit ratio (1: 1.93 were increased. P. fumosoroseus and V. lecanii were less effective than B. bassiana. The persistence of fungal pathogens was found to be higher in soil than the phyllosphere indicating that they can be naturally favored for the control of pests in groundnut.

  5. Respon Fungsional Menochilus sexmaculatus Fabricius terhadap Aphis Gossypii Glover

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    F. X. Wagiman

    1996-12-01

    Full Text Available Laboratory and field-cage experiments were conducted at the Universiti Pertanian Malaysia. Objective of the study was to determine the functional response of Menochilus sexmaculatus Fabricius (Coleoptera: Coccinellidae predating on chilli aphid Aphis gossypii Glover (Homoptera: Aphididae. The larvae and adults of the predaceous coccinellid exhibited the Hulling's Type II functional response. A first instar of the coccinellid predating on single first instar of the aphid within 24.6 minutes in the laboratory and 16.8 minutes in the field. While a fourth instar and an adult of the coccinellid predating on single fourth instar of the aphid within 4.2 and 1.5 minutes respectively.

  6. Species richness and resource availability: a phylogenetic analysis of insects associated with trees.

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    Kelly, C K; Southwood, T R

    1999-07-06

    The data on the number of species of insects associated with various trees in Britain have been reanalyzed to factor out possible bias from phylogenetic effects. It was found that tree availability (range and abundance) continues to provide a good predictor (r = 0. 852) of insect-species richness, slightly better than straightforward cross-species analyses. Of the two components of tree availability, tree abundance gives a much better prediction than tree range. The species richness on trees of major taxa with similar trophic habits (Lepidoptera and Hymenoptera/Symphyta and the two suborders of the Homoptera-Auchenorrhyncha and Sternorrhyncha) shows positive correlations; there is thus no evidence of competitive exclusion at this taxonomic level.

  7. Food habits of Nyctinomops macrotis at a maternity roost in New Mexico, as indicated by analysis of guano

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    Sparks, D.W.; Valdez, E.W.

    2003-01-01

    We examined 56 fecal pellets from under a maternity colony of big free-tailed bats (Nyctinomops macrotis) in the Jemez Mountains of northern New Mexico. The most important food items, listed in order of decreasing percent volume, were Cicadellidae, leafhoppers (26.7% volume, 58.9% frequency); Ichneumonidae, Ichneumon wasps (19.3% volume, 35.7% frequency); and Lepidoptera, moths (17.2% volume, 82.1% frequency). Overall, the most important orders as prey consumed, listed by decreasing percent volume, were Homoptera (27.6% volume, 62.5% frequency), Hymenoptera (19.5% volume, 37.5% frequency), Lepidoptera (17.2% volume, 82.1% frequency), Hemiptera (11.7% volume, 37.5% frequency), and Diptera (10.6% volume, 50.0% frequency). Our study documents an unusually varied diet, as previous studies indicated that these bats fed almost exclusively on moths.

  8. Primary structure of a novel neuropeptide isolated from the corpora cardiaca of periodical cicadas having adipokinetic and hypertrehalosemic activities.

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    Raina, A; Pannell, L; Kochansky, J; Jaffe, H

    1995-09-01

    A new neuropeptide hormone was isolated from the corpora cardiaca of the periodical cicadas, Magicicada species. Primary structure of the peptide as determined by a combination of automated Edman degradation after enzymatic deblocking with pyroglutamate aminopeptidase and mass spectrometry is: pGlu-Val-Asn-Phe-Ser-Pro-Ser-Trp-Gly-Asn-NH2. Synthetic peptide assayed in the green stink bug Nezara viridula caused a 112% increase in hemolymph lipids at a dose of 0.625 pmol, and a 67% increase in hemolymph carbohydrates at a dose of 2.5 pmol. Based on these results we designate this peptide, a first from order Homoptera, as Magicicada species-adipokinetic hormone (Mcsp-AKH).

  9. Insecticidal activity of three plants extracts against Myzus persicae (Sulzer, 1776 and their phytochemical screening

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    Billal NIA

    2015-11-01

    Full Text Available To reduce the use of synthetic pesticides and their negative effects on the environment, leaves extracts of Artemisia herba-alba Asso, Eucalyptus camaldulensis Dehnh and Rosmarinus officinalis L. were obtained with petroleum ether, ethanol and distilled water as solvents. These extracts were evaluated under laboratory conditions for their insecticidal effect against 3 to 4 days-old Myzus persicae individuals (Homoptera: Aphididae at 1, 2.5, 5, and 10 %. We made observations after 24 hours. Etheric extract of all plants was effective and caused mortalities (100 %, 53 % and 60 % respectively at the highest concentration. However, ethanolic and aqueous extracts did not show any significant insecticidal effect. The phytochemical screening showed the richness of etheric extract in terpenes. The results obtained suggest that we can make bioinsecticides based on leaves etheric extracts from these plants for use in integrated pest management.

  10. Incidência de insetos fitófagos e de predadores no milho e no feijão cultivados em sistema exclusivo e consorciado Insect phitophagous and predators incidence on maize and bean cultivated in exclusive and intercropped systems

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    Cristina Schetino Bastos

    2003-06-01

    Full Text Available Este trabalho foi conduzido em Coimbra, MG, no ano agrícola 1996/97 e objetivou avaliar a ocorrência de insetos fitófagos e de predadores no milho e no feijoeiro cultivados em sistema exclusivo e em policultivo. Foi realizado um cultivo de milho (25/10/1996 a 24/03/1997 e dois cultivos de feijão[o primeiro de 25/10/1996 a 20/01/1997 (cultivo "das águas" e o segundo de 25/03/1997 a 21/07/1997 (cultivo "da seca"]. Realizaram-se contagens diretas das populações de insetos fitófagos e de predadores nas culturas. Menores densidades populacionais de herbívoros considerados preferenciais da cultura do milho [Dalbulus maidis (Delong & Wolcott (Homoptera: Cicadellidae e Spodoptera frugiperda (Smith (Lepidoptera: Noctuidae] e do feijoeiro [Diabrotica speciosa (Germ., Cerotoma arcuata (Oliv. (Coleoptera: Chrysomelidae e Empoasca kraemeri (Ross & Moore (Homoptera: Cicadellidae] estiveram associadas ao cultivo consorciado. As densidades de herbívoros generalistas como Thrips tabaci Lind. (Thysanoptera: Thripidae e Pseudoplusia includens (Walk. (Lepidoptera: Noctuidae foram maiores no feijoeiro consorciado com o milho. No cultivo "das águas", o total de insetos fitófagos foi maior no feijoeiro consorciado com o milho do que no feijoeiro cultivado exclusivamente, sendo que o inverso ocorreu no cultivo "da seca". Os predadores Anthicus sp. (Coleoptera: Anthicidae e Hymenoptera: Formicidae foram mais abundantes no milho e no feijoeiro cultivados exclusivamente do que as culturas foram consorciadas.This work was carried out in Coimbra, MG,Brazil, during the agricultural year of 1996/97 and it had the objective of evaluating the phytophagous insects and predators occurrence in maize and bean cultivated in exclusive and policultive systems. One cultivation of maize (from 10/25/1996 to 03/24/1997 and two cultivation of bean were conducted [the first one from 10/25/1996 to 01/20/1997 (rainy period cultivation and the second one from 03/25/1997 a 07

  11. Comparative analysis of Solanum stoloniferum responses to probing by the green peach aphid Myzus persicae and the potato aphid Macrosiphum euphorbiae.

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    Alvarez, Adriana E; Broglia, Viviana G; Alberti D'Amato, Anahí M; Wouters, Doret; van der Vossen, Edwin; Garzo, Elisa; Tjallingii, W Fred; Dicke, Marcel; Vosman, Ben

    2013-04-01

    Plants protect themselves against aphid attacks by species-specific defense mechanisms. Previously, we have shown that Solanum stoloniferum Schlechtd has resistance factors to Myzus persicae Sulzer (Homoptera: Aphididae) at the epidermal/mesophyll level that are not effective against Macrosiphum euphorbiae Thomas (Homoptera: Aphididae). Here, we compare the nymphal mortality, the pre-reproductive development time, and the probing behavior of M. persicae and M. euphorbiae on S. stoloniferum and Solanum tuberosum L. Furthermore, we analyze the changes in gene expression in S. stoloniferum 96 hours post infestation by either aphid species. Although the M. euphorbiae probing behavior shows that aphids encounter more probing constrains on phloem activities-longer probing and salivation time- on S. stoloniferum than on S. tuberosum, the aphids succeeded in reaching a sustained ingestion of phloem sap on both plants. Probing by M. persicae on S. stoloniferum plants resulted in limited feeding only. Survival of M. euphorbiae and M. persicae was affected on young leaves, but not on senescent leaves of S. stoloniferum. Infestation by M. euphorbiae changed the expression of more genes than M. persicae did. At the systemic level both aphids elicited a weak response. Infestation of S. stoloniferum plants with a large number of M. persicae induced morphological changes in the leaves, leading to the development of pustules that were caused by disrupted vascular parenchyma and surrounding tissue. In contrast, an infestation by M. euphorbiae had no morphological effects. Both plant species can be regarded as good host for M. euphorbiae, whereas only S. tuberosum is a good host for M. persicae and S. stoloniferum is not. Infestation of S. stoloniferum by M. persicae or M. euphorbiae changed the expression of a set of plant genes specific for each of the aphids as well as a set of common genes. © 2012 The Authors Insect Science © 2012 Institute of Zoology, Chinese Academy of

  12. Contact and fumigant toxicity of plant essential oils and efficacy of spray formulations containing the oils against B- and Q-biotypes of Bemisia tabaci.

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    Kim, Soon-Il; Chae, Song-Hwa; Youn, Hee-Sung; Yeon, Seong-Hum; Ahn, Young-Joon

    2011-09-01

    The contact + fumigant toxicity of 92 plant essential oils and control efficacy of 18 experimental spray formulations containing nine selected essential oils (0.5 and 0.1% sprays) and six commercial insecticides to females from B- and Q-biotypes of Bemisia tabaci were evaluated using vapour-phase mortality and spray bioassays. Garlic and oregano (LC50 , 0.15 mL cm(-3) ) were the most toxic oils against B- and Q-biotype females. Strong fumigant toxicity to both biotype females was also obtained from catnip, cinnamon bark, clove bud, clove leaf, davana, savory and vetiver Haiti oils (LC50 , 0.17-0.48 mL cm(-3) ). The 0.5% sprays of these oils (except for thyme red oil) resulted in 90-100% mortality against both biotype females. Only garlic applied as 0.1% spray provided 100% mortality. Spinosad 100 g L(-1) suspension concentrate (SC) treatment resulted in 92 and 95% mortality against both biotype females, whereas acetamiprid 80 g L(-1) wettable powder (WP), imidacloprid 80 g L(-1) SC, thiamethoxam 100 g L(-1) water-dispersible granule (WDG) and pyridaben 200 g L(-1) WP treatments resulted in 89-100% mortality against B-biotype females only. In the light of global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment, the essential oils described, particularly garlic, cinnamon bark and vetiver Haiti, merit further study as potential insecticides for the control of B. tabaci populations as fumigants with contact action. Copyright © 2011 Society of Chemical Industry.

  13. Enhanced vitellogenesis in a whitefly via feeding on a begomovirus-infected plant.

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    Jian-Yang Guo

    Full Text Available BACKGROUND: The MEAM1 (B biotype Bemisia tabaci (Gennadius is one of the most widespread and damaging whitefly cryptic species. Our previous studies discovered that the MEAM1 whitefly indirectly benefits from interactions with the tomato yellow leaf curl China virus (TYLCCNV via accelerated ovarian development and increased fecundity. However, the physiological mechanism of begomoviruse-infected plants acting on the reproduction of the insect vector was unknown. METHODOLOGY/PRINCIPAL FINDINGS: Biochemical and molecular properties of vitellogenin (Vg and vitellin (Vt were characterized in the MEAM1 whitefly. In addition, kinetics of Vt levels in ovary and Vg levels in hemolymph in different stages were detected using a sandwich ELISA. The level of hemolymph Vg increased rapidly after eclosion. A significantly higher level of hemolymph Vg and ovary Vt were observed in whiteflies feeding on virus-infected tobacco plants than those feeding on uninfected plants. In order to detect the levels of Vg mRNA transcription, complete vitellogenin (Vg mRNA transcripts of 6474 bp were sequenced. Vg mRNA level in whiteflies feeding on virus-infected plants was higher than those feeding on uninfected plants. However, virus-infection of the whiteflies per se, as demonstrated using an artificial diet system, did not produce significant changes in Vg mRNA level. CONCLUSIONS/SIGNIFICANCE: In MEAM1 whitefly, increased levels of both vitellin and vitellogenin as well as increased transcription of Vg mRNA are associated with feeding on begomovirus-infected plants, thus providing a mechanism for accelerated vitellogenesis. We conclude that MEAM1 whitefly profits from feeding on begomovirus-infected plants for yolk protein synthesis and uptake, and thereby increases its fecundity. These results not only provide insights into the molecular and physiological mechanisms underlying the elevated reproduction of a whitefly species through its association with a begomovirus

  14. Insecticide effects of Ruta graveolens, Copaifera langsdorffii and Chenopodium ambrosioides against pests and natural enemies in commercial tomato plantation = Ação inseticida de Ruta graveolens, Copaifera langsdorffii e Chenopodium ambrosioides sobre pragas de tomate

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    Flávia Silva Barbosa

    2011-01-01

    Full Text Available The aim of this study was to evaluate the insecticide effect of watery leaf extracts of Ruta graveolens (Rutaceae, alcoholic leaf extracts of Copaifera langsdorffii (Caesalpinaceae and Chenopodium ambrosioides (Chenopodiaceae in the concentration of 5% under field conditions. The experiment design was randomized blocks with six replications. The parcels treated with plant extracts showed reduction in the population of pests when compared with the controlparcels. The extract elaborated with C. langsdorffii presented greater insecticidal effect under Bemisia tabaci (Hemiptera: Aleyrodidae and sum of pests. It was verified that after 24 hours ofspraying, the parcels treated with the extract of C. ambrosioides presented minor numbers of adults of Tuta absoluta (Lepidoptera: Gelechiidae, followed by the parcels treated with extract of R.graveolens. There were smaller numbers of parasitoid eggs of epidopterans Trichogramma sp. (Hymenoptera: Trichogrammatidae and sum of natural enemies (predators + parasitoids in the parcels that had received spraying with extracts from the plants of C. langsdorffii and C. ambrosioides, followed by R. graveolens, compared to the control. There were a smaller number of parasitoids from the family Eulophidae (Hymenoptera attacking caterpillars of T. absoluta in plants treated with R. graveolens, followed by C. langsdorffii and C. ambrosioides than in the control.O objetivo deste trabalho foi avaliar o efeito inseticida dos extratos aquosos de folhas de Ruta graveolens (Rutaceae e alcoólicos de folhas de Copaifera langsdorffii (Caesalpinaceae e de folhas de Chenopodium ambrosioides (Chenopodiaceae a 5%. O experimento foi em blocos casualizados com seis repetições. As parcelas tratadas tiveram redução na população de pragas, quando comparadas às parcelas sem nenhum tratamento. O extrato elaborado com C. langsdorffii apresentou maior efeito inseticida em Bemisia tabaci (Hemiptera: Aleyrodidae e soma das pragas

  15. Biodiversidad antropoentomofágica de la región de Zongolica, Veracruz, México

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    Julieta Ramos-Elorduy

    2008-03-01

    Full Text Available Durante dos años y medio (2003-2005 se rastrearon a los insectos que se ingieren en el área de Zongolica, Veracruz: para ello se entrevistó a la gente de ese municipio (200, para conocer cuáles especies ingerían. El total de especies registradas, ascendió a 57 distribuidas en los órdenes Orthoptera, Hemiptera, Homoptera, Megaloptera, Coleoptera, Lepidoptera e Hymenoptera, correspondiendo el mayor consumo al primer orden. De las especies registradas, 24 son nuevos registros de insectos comestibles para México. Estos se consumen tanto en estado inmaduro como en estado adulto y generalmente se ingieren asados. Hay una secuenciación estacional en el consumo de las diferentes especies y algunas de ellas (las cucarachas, la cuetla, la cuecla, los chapulines, los toritos, etc. se comercializan en los tianguis (puestos de venta callejeros informales que se realizan un día a la semana en diversos lugares del país o en el día de mercado en Zongolica. Existe el "protococultivo" de tres especies: una cucaracha (Periplaneta australasiae Fabricius y dos mariposas (Latebraria amphipyroides Guenée y Arsenura armida armida Cramer. La antropoentomofagía es un hábito ancestral en Zongolica.Anthropoentomophagic biodiversity of the Zongolica region, Veracruz, Mexico. During two and a half years (2003-2005 we recorded the insect species used as food at Zongolica, Veracruz State, Mexico. Interviews were made among people (200 of this municipality to know which insects they consumed. The total of registered species was 57 (Orthoptera, Hemiptera, Homoptera, Megaloptera, Coleoptera, Lepidoptera and Hymenoptera. The Orthoptera was the most frequently ingested. Twenty-four of these species were new records for edible insects of Mexico. They are eaten in immature stages or as adults, generally only roasted. Consumption is seasonal. Some species are commercialized in the "tianguis" (little town markets and/or in the larger Zongolica market. There is a

  16. Duração e viabilidade das fases pré-imaginais de Chrysoperla externa (Hagen alimentadas com Aphis gossypii Glover e Sitotroga cerealella (Olivier Duration and viability of Chrysoperla externa (Hagen pre-imago phases, fed with Aphis gossypii (Glover and Sitotroga cerealella (Olivier

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    Luciano Pacelli Medeiros Macedo

    2002-05-01

    Full Text Available Estudou-se a duração e a viabilidade das fases imaturas de Chrysoperla externa (Hagen (Neuroptera, Chrysopidae alimentadas com o pulgão do algodoeiro, Aphis gossypii Glover (Homoptera, Aphididae, e com a traça do milho, Sitotroga cerealella (Olivier (Lepidoptera: Gelechiidae. A pesquisa foi conduzida no Laboratório de Entomologia da Embrapa - CNPA, em Campina Grande, Paraíba, em 1998/99 em condições controladas sob temperatura de 25±2ºC, 70±10% UR e fotofase de 12 horas. O desenvolvimento pré-imaginal de C. externa decorreu normalmente: fase larval com três ínstares, pré-pupa e pupa. De acordo com os resultados, pode-se concluir que as larvas de C. externa alimentadas com A. gossypii apresentam uma duração significativamente maior para o primeiro e terceiro ínstares, que às alimentadas com S. cerealella. Entretanto, não há efeito dessas presas na viabilidade das fases desse predador, exceto para a de pré-pupa. C. externa pode ser criado em A. gossypii ou S. cerealella sem risco de perda de viabilidade, embora algumas fases possam ser mais longas.This work was carried out at the Laboratório de Entomologia da Embrapa - CNPA, in Campina Grande, state of Paraíba, Brazil, in 1998/99, to study the duration and viability of Chrysoperla externa (Hagen (Neuroptera, Chrysopidae larvae, fed with Aphis gossypii (Homoptera, Aphididae and Sitotroga cerealella (Lepidoptera: Gelechiidae, under controlled conditions. The temperature was 25+-2º C, 70+-10% UR and 12-hour photophase. The C. externa pre-imaginal development was normal: larval phase with three instars, pre-pupa and pupa. The results showed that C. externa larvae fed on A. gossypii had a first and third instar longer than the ones fed with S. cerealella. However, no effect was observed in the phases' viability, excepting the pre-pupa. C. externa can feed on both preys without viability loss, although this may enhance some phases' duration.

  17. Capacidad reguladora de Chrysoperla externa (Hagen sobre mosca blanca Trialeurodes vaporariorum (Westwood en tomate bajo invernadero

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    Mayerly Alejandra Castro-Lopez

    2016-11-01

    Full Text Available Trialeurodes vaporariorum Westwood (Hemíptera: Aleyrodidae es uno de los principales limitantes del cultivo de tomate Solanum lycopersicum, por generar problemas directos e indirectos en este sistema de producción; para el manejo de este insecto (mosca blanca se acude a excesivas aplicaciones de productos de síntesis química, sin obtener los mejores resultados. Este estudio consistió en evaluar, en condiciones de invernadero, la capacidad reguladora de Chrysoperla externa Hagen (Neuróptera: Chrysopidae sobre la mosca blanca presente en tomate. En plantas infestadas con individuos de T. vaporariorum se adicionó C. externa en niveles poblacionales de 80, 160 y 240 individuos en estado larval por planta, y se contó con un testigo sin depredador. Se empleó un diseño completamente al azar en condiciones de invernadero (temperatura promedio de 20 ºC y humedad relativa del 60 %. Se observaron diferencias estadísticamente significativas entre las densidades del depredador, con infestaciones de 35, 52 y 53 % de T. vaporariorum (tras cuatro semanas, correspondientes a las liberaciones de 240, 160 y 80 individuos por planta, respectivamente. Se observó que las plantas del testigo presentaron menor altura y número de ramas, respecto de los tratamientos en los cuales había presencia del depredador C. externa.

  18. Compatibilidad in vitro de Isaria fumosorosea (Wize Brown y Smith (Hypocreales: Clavicipitaceae con plaguicidas comerciales

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    Érika Paola Grijalba Bernal

    2014-01-01

    Full Text Available Los agricultores colombianos utilizan productos químicos con categorías toxicológicas I, II y III para el control de insectos como la mosca blanca Bemisia tabaci (Gennadius, 1889 (Hemiptera: Aleyrodidae; pero su uso indiscriminado genera un riesgo para la salud y el medio ambiente. El control microbiológico con hongos entomopatógenos surge como alternativa de control ambientalmente sostenible. No obstante, su empleo exitoso dentro de una estrategia de manejo integrado de plagas (MIP depende, en gran parte, del efecto de los productos químicos sobre el bioplaguicida. El objetivo del presente trabajo fue determinar la compatibilidad in vitro de un bioplaguicida con base en el hongo Isaria fumosorosea formulado como polvo mojable con cuatro fungicidas y cinco insecticidas comerciales. Para esto, se evaluó el efecto de tres concentraciones de los productos químicos: FR = dosis recomendada en campo, 0.5 x FR y 0.25 x FR sobre la germinación de los conidios y el número de unidades formadoras de colonia UFC/g de I. fumosorosea. Los cuatro fungicidas (Benlate, Carboxin Captan, Metalaxil-Mancozeb y Mancozeb en las tres dosis evaluadas fueron incompatibles con el bioplaguicida, mientras que el insecticida Thiametoxam fue compatible cuando se utilizó la dosis de 0.25 x FR.

  19. Performance of Bemisia tabaci Biotype B on Soybean Genotypes.

    Science.gov (United States)

    Cruz, P L; Baldin, E L L

    2017-04-01

    Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae) has been recognized as an important pest of many agricultural systems including soybean [Glycine max (L.) Merrill] crops. As an alternative to chemical control, the use of resistant genotypes represents an important tool for integrated pest management (IPM). This study aimed to evaluate the biological development of Bemisia tabaci biotype B confined on 13 soybean genotypes under greenhouse conditions. Initially, the nymphal period, complete development period (egg-adult), and the viability of the silverleaf whitefly nymphs were evaluated in all genotypes. Then, four genotypes promising for resistance ('Jackson,' UX-2569-159, 'P98Y11,' and 'TMG132 RR') and a susceptible genotype (PI-227687) were selected for further assays, where two insect populations were compared: a first population from the initial rearing (cabbage plants) and another corresponding to insects previously reared out on the selected genotypes. In addition to the parameters evaluated in preliminary tests, we also determined the viability and incubation period of eggs. Moderate levels of resistance (antibiosis/antixenosis) to B. tabaci biotype B were found in three genotypes. 'P98Y11' and 'TMG132 RR' were less suitable for insect development, extending the development cycle, and UX-2569-159 caused high nymphal mortality. We did not observe a significant increase in the level of plant resistance by the use of previously stressed insects. This suggests that the evaluation of a single whitefly generation may be sufficient to make correct decisions on promising soybean genotypes.

  20. Application of RNA-seq for mitogenome reconstruction, and reconsideration of long-branch artifacts in Hemiptera phylogeny

    Science.gov (United States)

    Song, Nan; An, Shiheng; Yin, Xinming; Cai, Wanzhi; Li, Hu

    2016-01-01

    Hemiptera make up the largest nonholometabolan insect assemblage. Despite previous efforts to elucidate phylogeny within this group, relationships among the major sub-lineages remain uncertain. In particular, mitochondrial genome (mitogenome) data are still sparse for many important hemipteran insect groups. Recent mitogenomic analyses of Hemiptera have usually included no more than 50 species, with conflicting hypotheses presented. Here, we determined the nearly complete nucleotide sequence of the mitogenome for the aphid species of Rhopalosiphum padi using RNA-seq plus gap filling. The 15,205 bp mitogenome included all mitochondrial genes except for trnF. The mitogenome organization and size for R. padi are similar to previously reported aphid species. In addition, the phylogenetic relationships for Hemiptera were examined using a mitogenomic dataset which included sequences from 103 ingroup species and 19 outgroup species. Our results showed that the seven species representing the Aleyrodidae exhibit extremely long branches, and always cluster with long-branched outgroups. This lead to the failure of recovering a monophyletic Hemiptera in most analyses. The data treatment of Degen-coding for protein-coding genes and the site-heterogeneous CAT model show improved suppression of the long-branch effect. Under these conditions, the Sternorrhyncha was often recovered as the most basal clade in Hemiptera. PMID:27633117

  1. Factors affecting population dynamics of maternally transmitted endosymbionts in Bemisia tabaci.

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    Huipeng Pan

    Full Text Available While every individual of Bemisia tabaci (Hemiptera: Aleyrodidae harbors the primary symbiont (P-symbiont Portiera, the infection frequencies of the six secondary symbionts (S-symbionts including Hamiltonella, Arsenophonus, Cardinium, Wolbachia, Rickettsia and Fritschea vary greatly among different populations. To characterize the factors influencing the infection dynamics of the six S-symbionts in B. tabaci, gene-specific PCR were conducted to screen for the presence of the P-symbiont Portiera and the six S-symbionts in 61 (17 B and 44 Q biotypes field populations collected from different plant species and locations in China. All individuals of the 61 populations hosted the P-symbiont Portiera, but none of them harbored Arsenophonus and Fritschea. The presence and infection rates of Hamiltonella, Cardinium, Rickettsia, Wolbachia and their co-infections Rickettsia + Hamiltonella (RH, Rickettsia + Cardinium (RC, Hamiltonella + Cardinium (HC and Rickettsia + Hamiltonella + Cardinium (RHC varied significantly among the 61 field populations; and the observed variations can be explained by biotypes, sexes, host plants and geographical locations of these field populations. Taken together, at least three factors including biotype, host plant and geographical location affect the infection dynamics of S-symbionts in B. tabaci.

  2. New Insecticides for Management of Tomato Yellow Leaf Curl, a Virus Vectored by the Silverleaf Whitefly, Bemisia tabaci

    Science.gov (United States)

    Smith, H. A.; Giurcanu, M. C.

    2014-01-01

    Abstract Greenhouse studies using a randomized complete block design were carried out to evaluate the effect of six insecticides on transmission of Tomato yellow leaf curl virus (TYLCV) by the silverleaf whitefly, Bemisia tabaci biotype B Gennadius (Hemiptera: Aleyrodidae) to tomato, Lycopersicon esculentum (Miller) (Solanales: Solanaceae), seedlings that were inoculated with whiteflies from a TYLCV colony in cages 3, 7, or 14 d after treatment with insecticide. The purpose was to reveal differences in residual efficacy of four materials that are nearing registration for use on tomato—cyazypyr, flupyradifurone, pyrafluquinazon, and sulfoxaflor—and to compare them with two established insecticides, pymetrozine and a zeta-cypermethrin/bifenthrin combination. Differences in efficacy were expected because these six materials represent five distinct modes of action and both contact and systemic materials. Percentage of tomato seedlings expressing virus symptoms tended to be lowest in seedlings treated with flupyradifurone. The zeta-cypermethrin/bifenthrin insecticide demonstrated comparable efficacy to flupyradifurone in some trials at 3 and 7 d after treatment inoculations, but not the 14 d after treatment inoculation. Pyrafluquinazon was not statistically different from cyazypyr or sulfoxaflor in percentage of plants with virus symptoms in any trial. Percentage virus in the cyazypyr and sulfoxaflor treatments was not statistically different in the 3 and 7 d after treatment inoculations. Among seedlings treated with insecticide, percentage with virus symptoms tended to be highest in the seedlings treated with pymetrozine. PMID:25368089

  3. Risk of damage to tomato crops by the generalist zoophytophagous predator Nesidiocoris tenuis (Reuter) (Hemiptera: Miridae).

    Science.gov (United States)

    Arnó, J; Castañé, C; Riudavets, J; Gabarra, R

    2010-02-01

    Nesidiocoris tenuis (Reuter) (Hem. Miridae) is a native zoophytophagous predator of the Mediterranean region, and its populations colonize tomato crops when they are not heavily treated with insecticides. This generalist predator has a high capacity for controlling insect pests, and it is currently commercially produced and released in some areas to control Bemisia tabaci (Gennadius) (Hem. Aleyrodidae). However, its status as a pest and/or as beneficial is controversial. Therefore, the aim of this study was to evaluate the risk of damage to tomatoes in extreme conditions of prey scarcity, as well as high predator populations. Three predator densities were tested in a greenhouse cage experiment during a summer tomato crop. The crop did not display any negative effect caused by the predators during the first six weeks of interaction, independently of the density released. However, subsequently, the effect was dramatic, both on the vegetative growth of the plant and on the production of fruits. The reduction in vegetative growth was located at truss eight and it was expressed mainly by a lower number of leaves and a shorter length of the shoot above the truss. There was a significant reduction of yield with a lower number of fruits collected and a smaller mean weight, although this was not observable until truss seven. It seems that feeding on the plant by this mirid bug competed with the vegetative growth and fruiting processes of the plant in the extreme conditions of prey shortage maintained in our experiment.

  4. Morphological characterization of Capsicum annuum L. accessions from southern Mexico and their response to the Bemisia tabaci-Begomovirus complex

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    Horacio Ballina-Gomez

    2013-12-01

    Full Text Available The high diversity of chili pepper (Capsicum annuum L. in Mexico offers an excellent alternative to search for wild and semi-domesticated genotypes as sources of resistance to the complex Bemisia tabaci (Genn. (Hemiptera: Aleyrodidae-Begomovirus, which has caused enormous losses in commercial production of various horticultural crops. The goal of the present work was to characterize ex situ 18 genotypes of C. annuum from southern Mexico through 47 morphological descriptors, and to evaluate its response to the B. tabaci-Begomovirus complex. Morphological characterization showed the variables calyx annular constriction (CAC, number of branch bifurcation (NBB, and calyx pigmentation (CP had the highest variation. Principal components analysis (PCA of 47 morphological characteristics showed that 12 components were selected as meaningful factors. These components explained 94% of the variation. Cluster analysis showed three major clusters and seven sub-clusters. On the other hand, evaluation of the response to B. tabaci-Begomovirus showed that the genotypes have differential susceptibility to this vector-pathogen complex. Genotypes 'Chawa', 'Blanco', 'Maax' and 'X'catic' were into the low susceptibility to B. tabaci and low severity of viral symptoms. Surprisingly, the genotype 'Simojovel' showed high susceptibility to whitefly, but was grouped into genotypes with low symptom severity. This study shows the potential of native germplasm of pepper to explore sources of resistance to the B. tabaci-Begomovirus complex.

  5. Recessive Resistance Derived from Tomato cv. Tyking-Limits Drastically the Spread of Tomato Yellow Leaf Curl Virus

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    Rita C. Pereira-Carvalho

    2015-05-01

    Full Text Available The tomato yellow leaf curl disease (TYLCD causes severe damage to tomato (Solanum lycopersicum L. crops throughout tropical and subtropical regions of the world. TYLCD is associated with a complex of single-stranded circular DNA plant viruses of the genus Begomovirus (family Geminiviridae transmitted by the whitefy Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae. The tomato inbred line TX 468-RG is a source of monogenic recessive resistance to begomoviruses derived from the hybrid cv. Tyking F1. A detailed analysis of this germplasm source against tomato yellow leaf curl virus-Israel (TYLCV-IL, a widespread TYLCD-associated virus, showed a significant restriction to systemic virus accumulation even under continuous virus supply. The resistance was effective in limiting the onset of TYLCV-IL in tomato, as significantly lower primary spread of the virus occurred in resistant plants. Also, even if a limited number of resistant plants could result infected, they were less efficient virus sources for secondary spread owing to the impaired TYLCV-IL accumulation. Therefore, the incorporation of this resistance into breeding programs might help TYLCD management by drastically limiting TYLCV-IL spread.

  6. Population variability of Bemisia tabaci (Genn.) in different hosts.

    Science.gov (United States)

    do Valle, G E; Lourenção, A L; Zucchi, M I; Pinheiro, J B; de Abreu, A G

    2013-10-17

    The silverleaf whitefly, Bemisia tabaci (Genn.) (Hemiptera: Aleyrodidae), is a cryptic species complex that contains some of the most damaging pests in tropical and subtropical regions. Recent studies have indicated that this complex is composed of at least 24 distinct and morphologically indistinguishable species that mainly differ in their ability to transmit phytoviruses, adapt to hosts, and induce physiological changes in certain hosts. The importance of this species has been increasing worldwide, because it serves as a phytovirus vector, particularly for geminiviruses, in economically important crops. Here, we aimed to examine the population variability of B. tabaci populations inhabiting 6 agricultural crops grown in 5 regions of Brazil and 1 region of the USA; BRrep [Brasília (DF, Brazil) - cabbage], ILsoj [Urbana (IL/USA) - soybean], BJabo [Bom Jesus da Lapa (BA, Brazil) - pumpkin], CPsoj [Campinas (SP, Brazil) - soybean], UBman [Ubatuba (SP, Brazil) - cassava], and PEmel [Petrolina (PE, Brazil) - melon]. Thirteen polymorphic loci with 50 alleles were observed, with an average of 2.37 (range: 2.00-2.91) alleles per population. The UBman and PEmel B. tabaci populations were the most differentiated, which was probably caused by insect adaptation to the host plant and the use of insecticides. A 33.87% inter-population variation was observed, indicating that microsatellites may be used to measure differentiation among these B. tabaci populations. Based on the comparison of microsatellites in the current study, only the Middle East-Asia Minor 1 population of B. tabaci was found in the six populations.

  7. Potential of Five Brazilian Populations of Phytoseiidae (Acari) for the Biological Control of Bemisia tabaci (Insecta: Hemiptera).

    Science.gov (United States)

    Cavalcante, Ana Cristina Cerqueira; dos Santos, Victor Lucas Vicente; Rossi, Letícia Caroline; de Moraes, Gilberto José

    2015-02-01

    Biotype B of the whitefly, Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae), causes considerable losses to growers worldwide. Phytoseiid mites have been successfully used for the control of this pest in several countries. The Brazilian phytoseiid fauna is very diverse and potentially useful for this purpose. The aim of this study was to evaluate five Brazilian populations of phytoseiids as candidates for the control of the whitefly, a serious pest of different crops worldwide. Evaluated species were Amblydromalus limonicus (Garman & McGregor), Amblyseius herbicolus (Chant), Amblyseius largoensis (Muma), Amblyseius tamatavensis (Blommers), and Neoseiulus tunus (De Leon), which are found naturally in Brazil and elsewhere. The work was conducted at 28±1°C, 75±10% relative humidity, and a photoperiod of 12:12 (L:D) h. All evaluated phytoseiids preyed on eggs of B. tabaci, with the highest levels of predation recorded for Am. herbicolus and N. tunus, and highest level of oviposition recorded for Am. tamatavensis. The results show the Brazilian populations of those three species to be promising as control agents of B. tabaci. Aleuroglyphus ovatus (Troupeau) (Acari: Acaridae) was found to be a suitable prey for the mass production of those predators. Complementary studies are considered justified, given the positive results of this study. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  8. Dispersal of Amblyseius swirskii (Acari: Phytoseiidae) on High-Tunnel Bell Peppers in Presence or Absence of Polyphagotarsonemus latus (Acari: Tarsonemidae).

    Science.gov (United States)

    Lopez, L; Smith, H A; Hoy, M A; Cave, R D

    2017-01-01

    Amblyseius swirskiiAthias-Henriot (Acari: Phytoseiidae) is a predatory mite used to control thrips (Thysanoptera), whiteflies (Bemisia tabaci Genn., Hemiptera: Aleyrodidae), and broad mites (BMs) (Polyphagotarsonemus latus Banks, Acari: Tarsonemidae). Dispersal of A. swirskii, using the ornamental pepper "Explosive Ember" as a banker plant was evaluated for control of BMs in high-tunnel peppers. Open-canopy plants (5 weeks old) versus closed-canopy plants (10-weeks old) were used to evaluate the effect of plant connectedness in A. swirskii dispersal, in the presence (two females per plant) and absence of BMs. Plots consisted of a single central banker plant and four bell peppers extending linearly north and south. Sets of all treatments were destructively sampled 1, 4, and 7 days after releasing A. swirskii Within 24 h, A. swirskii dispersed four plants away from the banker plants (1 m), regardless of the state of the canopy. Canopy connectedness did increase the presence of A. swirskii on the crop plants. Predatory mite numbers on closed-canopy treatments doubled within the 7-day sampling period, whereas no significant increase was observed on open-canopy treatments. The presence of BMs had no significant effect on the movement of A. swirskii The results suggest further experiments with A. swirskii and banker plants for control of BMs is warranted. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  9. Population Structure of the Greenhouse Whitefly, Trialeurodes vaporariorum (Westwood, an Invasive Species from the Americas, 60 Years after Invading China

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    Rui-Rui Gao

    2014-08-01

    Full Text Available Though the greenhouse whitefly, Trialeurodes vaporariorum (Westwood (Hemiptera: Aleyrodidae was introduced into China more than 60 years ago, the genetic diversity and structure of this exotic insect pest and virus vector have not been studied. To investigate the population genetic characteristics of this invasive species and to identify potential invasion routes, the genetic diversity and population structure of 17 collections of T. vaporariorum from nine provinces in China were analyzed using seven microsatellite loci. The results of the analyses indicated that the genetic diversity for the populations examined from the four provinces: Jilin, Ningxia, Guizhou and Qinghai, was lower than the genetic diversity of populations from the five provinces: Yunnan, Shandong, Shanxi, Liaoning, and Gansu. The T. vaporariorum populations analyzed in this study grouped as two distinct genetic clusters based on the analysis using STRUCTURE, whereas, 8 clusters were identified based on the BAPS analysis. Of the 136 genetic distance (Fst values, 128 (94% were associated with a significant exact test. However, there was no significant relationship between Fst and geographical distance. These results demonstrate that populations of T. vaporariorum in China exhibit significant genetic differentiation, indicating the likelihood that multiple introductions of T. vaporariorum into China have occurred. Also, the populations collected from the provinces of Jilin, Ningxia, Guizhou and Qinghai appear to represent secondary introductions originating from other Chinese provinces.

  10. Occurrence of Entomopathogenic Fungi from Agricultural and Natural Ecosystems in Saltillo, México, and their Virulence Towards Thrips and Whiteflies

    Science.gov (United States)

    Sánchez-Peña, Sergio R.; Lara, Jorge San-Juan; Medina, Raúl F.

    2011-01-01

    Entomopathogenic fungi were collected from soil in four adjacent habitats (oak forest, agricultural soil, pine reforestation and chaparral habitat) in Saltillo, México using the insect bait method with Tenebrio molitor (L.) (Coleoptera: Tenebrionidae) larvae as bait. Overall, of the larvae exposed to soil, 171 (20%) hosted Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae), 25 (3%) hosted Metarhizium anisopliae (Metschnikoff) Sorokin (Hypocreales: Clavicipitaceae) and 1 (0.1%) hosted lsaria (=Paecilomyces) sp. (Hypocreales: Cordycipitaceae). B. bassiana was significantly more frequent on larvae exposed to oak forest soil. M. anisopliae was significantly more frequent on larvae exposed to agricultural soil. From the infected bait insects, 93 isolates of B. bassiana and 24 isolates of M. anisopliae were obtained. Strains were tested for their infectivity against Cuban laurel thrips, Gynaikothrips uzeli Zimmerman (Thysanoptera: Phlaeothripidae) and the greenhouse whitefly, Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae). B. bassiana isolates caused the highest mortality on thrips (some causing 88% mortality after 6 days); both fungal species caused similarly high mortality levels against whiteflies (75%) after 6 days. Large amounts of germplasm of entomopathogenic fungi, fundamentally B. bassiana and M. anisopliae, exist in the habitats sampled; pathogenicity varied among strains, and some strains possessed significant virulence. Soils in these habitats are reservoirs of diverse strains with potential for use in biocontrol. PMID:21521145

  11. Side effects of some pesticides on the silverleaf whitefly’s parasitoid, Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae under laboratory conditions

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    Mustafa PORTAKALDALI

    2015-12-01

    Full Text Available The silverleaf whitefly, Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae is one of major pests in greenhouses vegetable cultivation. Eretmocerus mundus Mercet (Hymenoptera: Aphelinidae has an important role among effective parasitoids used in biological control of the silverleaf whitefly. Nondestructive or less destructive pesticides against this parasitoid should be preferred in the scope of biological control. For this goal, side effects of 8 plant protection products, including spinosad, pyriproxyfen, abamectin, emamectin benzoate, copper oxychloride, kresoxim-methyl+boscalid, dimethoate and propineb+cymoxanil on pupae and adults of E. mundus were tested in this laboratory study conducted according to IOBC standards. As a result, pesticides containing spinosad, abamectin and dimethoate were determined as highly destructive to pupae and adults of E. mundus, and pesticide containing emamectin benzoate was found as moderately harmful. As for propineb+cymoxanil, pyriproxyfen, kresoxim-methyl+boscalid and copper oxychloride, they were determined as ineffective on the parasitoid under laboratory conditions. These results obtained from experiments that were conducted under laboratory conditions also have to be supported by field or semi-field experiment’s results.

  12. Aspectos biológicos y poblacionales de Nasonovia ribisnigri y Aulacorthum solani sobre lechuga

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    Vasicek Araceli

    2002-01-01

    Full Text Available Se estimó la influencia de los cultivares Criolla Blanca, Cuatro Estaciones y Gallega, sobre la biología y los parámetros poblacionales de Nasonovia ribisnigri y Aulacorthum solani (Homoptera: Aphidoidea a 10±1ºC y HR de 90%. Los períodos ninfal, pre-reproductivo y post-reproductivo de N. ribisnigri fueron más largos sobre Cuatro Estaciones, no así el reproductivo. En A. solani el período ninfal fue más largo sobre Criolla Blanca y Cuatro Estaciones resultando el reproductivo mayor sobre Cuatro Estaciones. Las tasas intrínsecas de crecimiento natural (r m de N. ribisnigri y A. solani fueron mayores sobre Criolla Blanca y Gallega, respectivamente. De acuerdo a la especie predominante convendría utilizar Cuatro Estaciones para N. ribisnigri y Criolla Blanca para A. solani, en épocas frías.

  13. Triterpenoides de frutos de Melia azedarach: su potencial como agentes de control de insectos

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    Martina Díaz

    2011-12-01

    Full Text Available Melia azedarach L. (Meliaceae es nativa de Asia pero ha sido naturalizada en muchas partes del planeta. Variados compuestos bioactivos estructuralmente complejos fueron aislados de especímenes asiáticos. Este estudio tuvo como objetivo determinar la actividad anti-insecto de extractos orgánicos de frutos de M. azedarach de especímenes uruguayos y elucidar las estructuras de los compuestos activos. El fraccionamiento sistemático de extractos etanólicos llevó a la obtención de una fracción rica en limonoides con actividad contra diferentes insectos modelo. Mostró fuerte deterrencia frente a larvas de Spodoptera littoralis (Lepidoptera: Noctuidae y adultos de Epilachna paenulata (Coleoptera: Coccinellidae en bioensayos de opción. Además, inhibió el asentamiento de Myzus persicae y Rhopalosiphum padi (Homoptera: Aphididae. Sin embargo, no mostró toxicidad por contacto contra adultos de Nezara viridula (Hemiptera: Pentatomidae. Dos compuestos nunca antes reportados en esta especie vegetal y tres previamente reportados pero nunca antes testados contra los insectos nombrados fueron aislados de la fracción. En síntesis, una fracción rica en triterpenoides del extracto etanólico de frutos de M. azedarach mostró potencial variable contra las diferentes especies de insectos plaga modelo, enfatizando así la importancia de testar los potenciales agentes biocontroladores contra diferentes insectos blanco.

  14. Entomofauna associated to horticultural crops under organic and conventional practices in Cordoba, Argentina; Entomofauna asociada a cultivos horticolas organicos y convencionales en Cordoba, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Zalazar, Laura; Salvo, Adriana [Universidade Nacional de Cordoba (Argentina). Facultad de Ciencias Exactas Fisicas y Naturales. Centro de Investigaciones Entomologicas de Cordoba (CIEC)

    2007-09-15

    Farming practices and the addition of chemical synthetic substances in conventional agroecosystems are detrimental mainly to natural enemies of phytophagous insects, diminishing the natural regulation of pest insects. On the other hand, in organic agriculture, biological processes and care of the environment are favoured, hence an increase in insect biodiversity is predicted in this type of systems. In this work, abundance, richness of insects and proportion of functional groups were compared through a single quantitative sampling of insects in horticultural crop fields, three under organic and three under conventional management practices. Insect species richness, total and for guilds (phytophagous and entomophagous insects) were significantly higher in organic orchards, and also was the abundance of entomophagous insects. Richness and abundance of all insect orders (with exception of Homoptera abundance), were higher in orchards under organic management, being significant the differences for richness of Coleoptera and richness and abundance of Hymenoptera. Similar tendencies were observed in data obtained through sweep net in weeds. These results suggest that organic practices increase the diversity of species, particularly that of natural enemies. (author)

  15. ON THE PALEOFAUNA INVERTEBRATES (MOLLUSCA, ARTROPODA; INSECTA OF DIATOMITE DEPOSITS OF SHAMB–1 LOCALITY (SISIAN SUITE, EARLY PLEISTOCENE, ARMENIA

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    М. A. Маrjanyan

    2016-01-01

    Full Text Available Aim. The study of fossil insects from diatomaceous sediments of Shamb-1 locality of Sisian Suite (Early Pleistocene. The collection of fossils plants and animals of Institute of Botany of NAS RA and authors' findings served as material for study.Methods. The material is processed and prepared for study by conventional methods in paleontology for prints and fossils of insects from diatomaceous sediments. There are 654 samples studied: 2 samples were with mollusks’ imprints and 652 samples with imprints of insects, from which preserved marks on 291samples allowed to identify them up to order, family, genus and species.Results. The studied material refers to the Mollusca and Arthropoda (Insecta types. Insects are represented by species of orders Orthoptera (2 fam., Homoptera (1 fam., Heteroptera (2 fam., Coleoptera (15 fam., Hymenoptera (2 fam., Diptera (1 fam.. Coleopteras dominate among them and are presented with following species of the family – Carabidae, Dytiscidae, Hydrophilidae, Histeridae, Staphylinidae, Silphidae, Elateridae, Buprestidae, Lampyridae, Scarabaeidae, Chrysomelidae, Tenebrionidae, Coccinellidae, Cerambycidae, Curculionidae.Main conclusions. An analysis of the taxonomic composition of paleofauna was done, which corresponds to the recent fauna and with considering modern ecological characteristics of systematical groups and species. In the investigated location of Shamb-1 a version is suggested about the palaeolandscapes and palaeoclimate in the Early Pleistocene.

  16. Continuous Measurement of Macronutrient Ions in the Transpiration Stream of Intact Plants Using the Meadow Spittlebug Coupled with Ion Chromatography1

    Science.gov (United States)

    Malone, Michael; Herron, Michelle; Morales, M.-Angeles

    2002-01-01

    A method is described for continuous, nondestructive analysis of xylem-borne mineral nutrients in intact transpiring plants. The method uses the xylem-feeding insect the meadow spittlebug (Philaenus spumarius L. [Homoptera: Cercopidae]). This insect will feed from a wide range of plant species and organs. Insect excreta can be collected at all times of the day and night, and its mineral ion content can be analyzed rapidly, and without purification, by ion chromatography. The excreta will have a mineral content virtually identical to that of xylem sap. Cages suitable for containing the insects and collecting excreta from any desired location on plants in both laboratory and greenhouse are described. Even in the greenhouse, evaporation had only a minor effect on the sample ion content. Example results are presented which illustrate dynamics, over several days, in the xylem concentrations of sodium (Na+), potassium (K+), NH4+, magnesium (Mg2+), calcium (Ca2+), chloride (Cl−), NO3−, PO43−, and SO42−. These data were collected from young plants growing in pots of compost in the laboratory and from fully mature pepper (Capsicum annuum L. cv Bellboy) plants growing in hydroponics (rockwool) in the greenhouse. This method should facilitate studies of macronutrient uptake and transport in a range of plants and environments. PMID:12428008

  17. Continuous measurement of macronutrient ions in the transpiration stream of intact plants using the meadow spittlebug coupled with ion chromatography.

    Science.gov (United States)

    Malone, Michael; Herron, Michelle; Morales, M-Angeles

    2002-11-01

    A method is described for continuous, nondestructive analysis of xylem-borne mineral nutrients in intact transpiring plants. The method uses the xylem-feeding insect the meadow spittlebug (Philaenus spumarius L. [Homoptera: Cercopidae]). This insect will feed from a wide range of plant species and organs. Insect excreta can be collected at all times of the day and night, and its mineral ion content can be analyzed rapidly, and without purification, by ion chromatography. The excreta will have a mineral content virtually identical to that of xylem sap. Cages suitable for containing the insects and collecting excreta from any desired location on plants in both laboratory and greenhouse are described. Even in the greenhouse, evaporation had only a minor effect on the sample ion content. Example results are presented which illustrate dynamics, over several days, in the xylem concentrations of sodium (Na(+)), potassium (K(+)), NH(4)(+), magnesium (Mg(2+)), calcium (Ca(2+)), chloride (Cl(-)), NO(3)(-), PO(4)(3-), and SO(4)(2-). These data were collected from young plants growing in pots of compost in the laboratory and from fully mature pepper (Capsicum annuum L. cv Bellboy) plants growing in hydroponics (rockwool) in the greenhouse. This method should facilitate studies of macronutrient uptake and transport in a range of plants and environments.

  18. In vitro host range of the Hz-1 nonoccluded virus in insect cell lines.

    Science.gov (United States)

    McIntosh, Arthur H; Grasela, James J; Ignoffo, Carlo M

    2007-01-01

    A total of 13 insect cell lines spanning 4 orders (Lepidoptera, Coleoptera, Diptera, and Homoptera) were tested for their ability to replicate the nonoccluded virus Hz-1. Only the Lepidopteran cell lines supported replication of the virus with TN-CL1 and BCIRL-HZ-AM1 producing the highest titers of 2.4 x 10(8) tissue culture infective dose (TCID)50/ml and 2.0 x 10(8) TCID50/ml, respectively. A codling moth cell line (CP-169) was the only Lepidopteran cell line that did not replicate the virus and transfection of this cell line with Hz-1 DNA failed to replicate the virus. Also, transfection with DNA from a recombinant baculovirus carrying the red fluorescent protein gene (AcMNPVhsp70 Red) was not expressed in CP-169 cells. The replication cycle of Hz-1 in BCIRL-HZ-AM1 cells showed that this virus replicated rapidly starting at 16 h postinoculation (p.i.) and reaching a peak titer of 1.0 x 10(8) TCID50/ml 56 h postinoculation. Hz-1 when compared with several other baculoviruses has the widest in vitro host spectrum.

  19. Búsqueda y reconocimiento de los enemigos naturales y hospedantes alternos de las principales plagas. En flores bajo invernadero en la sabana de Bogotá

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    Martha E. Andrade

    1989-01-01

    Full Text Available Las plagas que atacan cultivos de llores bajo invernadero son cada vez más importantes por la gravedad de su daño y por la alta densidad con que suelen presentarse. Para su control se ha acudido principalmente a la utilización de productos químicos, lo cual conduce a un aumento en los costos de producción, a contaminar el medio ambiente, a afectar la salud humana y a crear resistencia de los insectos a los insecticidas. Debido a esto, es necesario incluír dentro de los programas de control a los reguladores naturales de las plagas: parasitoides, depredadores y microorganismos entornógenos. En el presente trabajo se registran los enemigos naturales más importantes de las principales plagas en llores bajo invernadero (crisantemo, rosa y clavel: Liriomyza huidobrensis Blanchard, L. trifolii Burgess (Diptera: Agrornyzídae; Myzuz persicae Sulzer (Homoptera: Aphididae; Tetranychus urticae Koch y T. cinnabarinus Boísduval (Acarina: Tetranychidae; también se señalan las plantas hospedantes alternas presentes en las localidades donde se realizó la investigación.

  20. For the Aphid fauna in the territory of Yenisei river basin. Communication 1. Aphids on coniferous plants

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    A. V. Gurov

    2016-02-01

    Full Text Available The paper reports on new and previously not well-known data on insufficiently studied fauna of aphids living on coniferous trees in Central Siberia of the basin of Yenisei river. This region is the extensive transect of latitudinal geographic zones from semi-desert in the South to the arctic deserts in the North. That is why this region is very peculiar. This is the reason for insufficient study of regional entomological fauna. Aphids (Homoptera: Aphidoideaare a very taxonomically and ecologically heterogeneous group of insects. The aphids living on conifer trees are notstudied completely on the territory of Yenisei basin. Due to this, the studying of not well-known and economicallyimportant aphids is actual. For example, the insufficient study of regional aphids is confirmed by the fact, that duringthree weeks only of the work for INTAS-94-0930 Project two new aphid species were found and described on thisterritory. Also, the new species of family Mindaridae, which was described in Mongolia in 1980, was found in Siberiafor the first time. These finds indicate the real possibility to describe an interesting conifer aphid complex in the absolutely unstudied forested territory between Angara and Lower Tunguska rivers. Geographical location, dates ofcollection and feeding preferences of different species are described. A general review of Yenisei basin Siberian aphidfauna is suggested for the first time ever.

  1. Predatory potential of Chrysoperla carnea and Cryptolaemus montrouzieri larvae on different stages of the mealybug, Phenacoccus solenopsis: a threat to cotton in South Asia.

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    Khan, Hafiz Azhar Ali; Sayyed, Ali H; Akram, Waseem; Raza, Sabtain; Ali, Muhammad

    2012-01-01

    The outbreaks of mealybug, Phenacoccus solenopsis Tinsley (Homoptera: Pseudococcidae), have created problems to cotton crops in South Asia in the recent years. To control this menace, predatory potential of Chrysoperla carnea and Cryptolaemus montrouzieri larvae were investigated under laboratory conditions (27 ± 5° C and 65 ± 5% RH). The experiments were conducted in no choice (only first, second, or third instar larvae of mealybug were offered at a time) and choice (first, second, and third instar larvae were offered simultaneously) feeding tests. Both predators had high consumption rates, with C. montrouzeiri being the most voracious feeder. In the no choice feeding tests, third instar larvae of C. montrouzeiri devoured the highest mean number of first instar P. solenopsis (439.38) In the choice feeding tests, a similar number of first instar nymphs (410) were consumed. In both feeding tests, C. carnea devoured relatively fewer numbers of P. solenopsis than C. montrouzeiri. Manly's preference index suggested that the both predators preferred first instar nymphs of P. solenopsis over second or third instar nymphs. Furthermore, studies on developmental rate and fecundity revealed that first instar nymphs of P. solenopsis significantly reduced development time but increased the fecundity of both predators.

  2. Comparison of the ionizing radiation effects on cochineal, annatto and turmeric natural dyes

    Science.gov (United States)

    Cosentino, Helio M.; Takinami, Patricia Y. I.; del Mastro, Nelida L.

    2016-07-01

    As studies on radiation stability of food dyes are scarce, commercially important natural food grade dyes were evaluated in terms of their sensitivity against gamma ionizing radiation. Cochineal, annatto and turmeric dyes with suitable concentrations were subjected to increasing doses up to 32 kGy and analyzed by spectrophotometry and capillary electrophoresis. The results showed different pattern of absorbance versus absorbed dose for the three systems. Carmine, the glucosidal coloring matter from the scale insect Coccus cacti L., Homoptera (cochineal) remained almost unaffected by radiation up to doses of about 32 kGy (absorbance at 494 nm). Meanwhile, at that dose, a plant-derived product annatto or urucum (Bixa orellana L.) tincture presented a nearly 58% reduction in color intensity. Tincture of curcumin (diferuloylmethane) the active ingredient in the eastern spice turmeric (Curcuma longa) showed to be highly sensitive to radiation when diluted. These data shall be taken in account whenever food products containing these food colors were going to undergo radiation processing.

  3. Dietary analysis of Homonota darwini (Squamata: Gekkoni-dae in Northern Patagonia

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    Marcelo E. KUN, Carla PIANTONI, John D. KRENZ, Nora R. IBARGÜENGOYTÍA

    2010-08-01

    Full Text Available Our study investigated the diet of the southernmost gecko in the world, Homonota darwini. Fifty-three specimens were captured during spring and summer in four locations in Patagonia, Argentina. The stomach contents of the specimens were identified, and we found that prey consisted of six main groups: Coleoptera, Hymenoptera, Homoptera and Araneae, and the adults and larvae of moth Lepidoptera. Lepidoptera was the major dietary component. The presence of ants and moths as common prey suggests an ambush feeding strategy. In spring, females consumed more ants than males although no other dietary differences between males and females were evident. We found nine geckos with empty stomachs and six parasitized by nematodes. Presence of empty stomachs corroborates previous observations of other nocturnal geckos and non-gecko lizards. Reduced foraging success of nocturnal lizards could be due to difficulty in prey detection due to dim light, reduced or erratic activity of insect prey at night, or shorter activity times of geckos relative to diurnal success. Sex and season were not associated with the incidence of empty stomachs. Principal component analysis showed that four food alternatives correlated with season. The constraint of nocturnality, coupled with low night-time temperatures restricting feeding to only a few hours after sunset, appear to have caused a generality of diet which may limit energy acquisition. We conclude that H. darwini is an arthropod generalist and likely an ambush forager, as are many other nocturnal gekkonids [Current Zoology 56 (4: 406–410, 2010].

  4. Mutualisme pucerons – fourmis : étude des bénéfices retirés par les colonies d'Aphis fabae en milieu extérieur

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    Verheggen F.

    2009-01-01

    Full Text Available Aphid – ant mutualism: an outdoor study of the benefits for Aphis fabae. Aphid – ant relationships are common examples of mutualism. Aphids are indeed submitted to predation and therefore require protection, while ants are continuously looking for new sugar sources. The present work aimed to study the benefits that a mutualistic relationship with Lasius niger (Hymenoptera, Formicidae could bring to the black bean aphid Aphis fabae (Homoptera, Aphididae. Several parameters were observed in the field, on broad bean plants infested with an initial amount of 100 A. fabae and in presence or not of a L. niger colony. More aphids were observed on plants being visited by ants as well as a higher proportion of winged individuals. One explanation is that fewer predators were observed on plants being visited by ants, demonstrating their protective role. However, the number of parasitized aphids was not reduced in presence of L. niger. On the other hand, fewer different aphid species were present on plants foraged by ants, what suggests that they could exert a predation on unattended aphids. Our observations do not allow to conclude on any impact of L. niger on the fitness of the aphid host plant, although fewer exuvia and honeydew spots were observed when they were present. All these results confirm that L. niger increase the fitness of A. fabae colonies mainly by decreasing the number of predators and by reducing competition from aphid species unattended by ants.

  5. Host races of the cotton aphid, Aphis gossypii, in asexual populations from wild plants of taro and brinjal.

    Science.gov (United States)

    Agarwala, B K; Choudhury, Parichita Ray

    2013-01-01

    Worldwide, several studies have shown that adaptation to different host plants in phytophagous insects can promote speciation. The cotton aphid, Aphis gossypii Glover (Homoptera: Aphididae: Aphidini), is a highly polyphagous species, but its populations increase by parthenogenetic reproduction alone in Indian subcontinent. This study showed that genotypes living in wild plants of taro, Colocasia esculenta var. esculenta (L.) Schott (Alismatales: Araceae), and brinjal, Solanum torvum Swartz (Solanales: Solanaceae), behave as distinct host races. Success rates of colonization after reciprocal host transfers were very poor. Clones of A. gossypii from wild taro partly survived in the first generation when transferred to wild brinjal, but nymph mortality was 100% in the second generation. In contrast, brinjal clones, when transferred to taro, could not survive even in the first generation. Significant differences between the clones from two host species were also recorded in development time, generation time, fecundity, intrinsic rate of increase, net reproductive rate, and mean relative growth rate. Morphologically, aphids of wild taro clones possessed longer proboscis and fore-femora than the aphids of the brinjal clones. The results showed that A. gossypii exists as distinct host races with different abilities of colonizing host plants, and its populations appear to have more potential of sympatic evolution than previously regarded.

  6. Lebensspuren holzzerstörender Organismen an fossilen Hölzern aus dem Tertiär der Insel Lesbos, Griechenland

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    H. Süss

    2001-01-01

    Full Text Available Lebensspuren (Schadbilder holzzerstörender Organismen an fossilen Holzresten aus dem Untermiozän von Lesbos (Griechenland werden beschrieben. Von pflanzlichen Holzzerstörern konnten Bakterien, imperfekte Pilze, Weiß- und Braunfäulepilze und in das Holz eingewachsene Wurzeln nachgewiesen werden. Von tierischen Holzzerstörern wurden Termitenfraß, durch Pflanzensauger (Homopteren verursachtes Wundgewebe, Larvenfraß der Kambium-Minierfliege Palaeophytobia (Agromyzidae, Diptera und Fraßgänge mit Koprolithen verschiedener Käferarten (Anobiiden? und Milben (Acari gefunden. Außerdem werden durch Kristallisationsvorgänge im Holz verursachte kugelförmige Gebilde beschrieben. Traces of wood destroying organisms on fossil wood from the Lower Miocene of Lesbos (Greece are described. Among nonanimal wood destroyers evidence is presented of bacteria, Fungi imperfecti, whiterot and brownrot fungus and penetrating roots. Animal wood destroyers include termite feeding traces, wound tissues produced by plant suckers (Homoptera, larval feeding traces of the cambium miner Palaeophytobia (Agromyzidae, Diptera and feeding channels, with coprolites, of several beetle species (Anobiidae? and Mites (Acari. In addition globe-like structures produced in the wood through crystallization processes are described. doi:10.1002/mmng.20010040105

  7. Weed host specificity of the aphid, Aphis spiraecola: developmental and reproductive performance of aphids in relation to plant growth and leaf chemicals of the Siam weed, Chromolaena odorata.

    Science.gov (United States)

    Agarwala, B K; Das, Jhuma

    2012-01-01

    Density, distribution, and nutritional quality of plants are the causal basis of host plant selection in aphids. Nutritional qualities of a plant vary according to its growth stage and also in response to seasonal variation. How host plant growth stages shape aphid performance was studied in Aphis spiraecola Patch (Homoptera: Aphididae) on the perennial Siam weed, Chromolaena odorata (L.) King and Robinson (Asterales: Asteraceae). This plant species is the preferred host in the hot and humid tropical parts of northeast and southern India. Variations in developmental and reproductive performances in apterous viviparous female aphids were recorded in relation to differences in leaf chemicals in different growth stages of C. odorata. Aphids reproduced at higher rates in the vegetative stage of C. odorata when developmental time was shortest, and fecundity was higher in a longer reproductive time. Intrinsic rate of increase and net reproductive rate were also recorded to be higher in the vegetative stage of the weed host. In the vegetative stage, leaves contained higher quantity of proteins and nitrogen, which are vital for insect reproduction. Results of this study have demonstrated that A spiraecola showed synchronization of its developmental and reproductive performances to growth stages of C. odorata, which occur in high abundance in the study area.

  8. Predation of the Peach Aphid Myzus persicae by the mirid Predator Macrolophus pygmaeus on Sweet Peppers: Effect of Prey and Predator Density

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    Lara De Backer

    2015-06-01

    Full Text Available Integrated Pest Management strategies are widely implemented in sweet peppers. Aphid biological control on sweet pepers includes curative applications of parasitoids and generalist predators, but with limited efficiency. Macrolophus pygmaeus is a zoophytophagous predator which has been reported to predate on aphids, but has traditionally been used to control other pests, including whiteflies. In this work, we evaluate the effectiveness of M. pygmaeus in controlling Myzus persicae (Homoptera: Aphididae by testing different combinations of aphid and predator densities in cage-experiments under greenhouse conditions. The impact of the presence of an alternative factitious prey (E. kuehniella eggs was also investigated. Macrolophus pygmaeus, at densities of four individuals/plant, caused rapid decline of newly established aphid populations. When aphid infestations were heavy, the mirid bug reduced the aphid numbers but did not fully eradicate aphid populations. The availability of a factitious prey did not influence M. pygmaeus predation on aphids. Based on our data, preventive application of M. pygmaeus, along with a supplementary food source , is recommended to control early infestations of aphids.

  9. Temporal and spatial changes in the diet of Hyla pulchella (Anura, Hylidae in southern Uruguay

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    Inés da Rosa

    2004-12-01

    Full Text Available In this article we report the diet of a population of the hylid frogHyla pulchella from southeastern Uruguay. We collected the specimens in ponds, where we identified microenvironments defined by the invertebrate assemblage, during one year divided into two seasons (warm and cold. We taxonomically determined 10365 invertebrates belonging to 21 categories in the digestive tracts of frogs. Weestimated the diversity of the diet and alimentary preference according to microenvironments and seasons. We estimated the expected richness of both diet and prey availability using a null model based on the hypergeometric distribution. We performed Discriminant Analyses and Kruskal-Wallis tests to detect changes in prey availability among microenvironments and between seasons. The overall diet in terms of frequencies was composed primarily of arthropods (mainly Araneae, Diptera, Hymenoptera, and Coleoptera and in terms of volume, by larvae. The most relevantitems to study the microenvironmental and seasonal variation in the available preys were Araneae, Collembola, Homoptera, Hymenoptera, Diptera, Dictioptera, Lepidoptera, Coleoptera, and larvae. Based on the null model curves and preference indexes we inferred positive selection by larvae, Isopoda, Dictioptera, Lepidoptera, and Diptera, and negative selection by Collembola and Hymenoptera. The diversityof diet and the null model curves indicated that the diet changes among microenvironments and seasons. This frog may be considered as a middle generalist predator, with some selective behavior and a combined search strategy (active and sit-and-wait. We conclude that the knowledge about the availability of preys is a relevant tool for trophic studies.

  10. Geographical distribution of invasive insect species in Albania

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    KEÇI Erjola

    2012-09-01

    Full Text Available Albania, just like every other country in the world, has been threatened by invasive species for years now. Although most of the invasive species have not a big impact in environment and economy of the country where they are introduced, some “good” introduced species at the beginning can turn to harmful invaders. Unlike most other pollutants, the effects of biological invaders are likely to increase through time as existing populations expand, even ifnew introductions are halted. Physical and geographical traits of Albania, such as habitat fragmentation, long coastline withmany harbors, facilitate the successful introduction of harmful invasive insect species. The aim of our work was to study thegeographical distribution, time and sites of introduction of invasive insects in Albania. Sampling expeditions were organized in13 cities belonging to 4 regions (south, north, west, east region in Albania. During 2009-2010 we collected 478 individualsbelonging to 5 insects orders, 15 families and 21 species. Individuals collected are classified as below: oder Lepidoptera, 5families, 8 species; order Coleoptera, 4 families, 6 species; order Homoptera, 3 families, 4 species; order Diptera, 2 families, 2species; order Prostigmata, 1 family, 1 specie. Many of these invasive insects are found from us in territories far away fromintroduction site.

  11. Fungi associated with the hemlock woolly adelgid, Adelges tsugae, and assessment of entomopathogenic isolates for management.

    Science.gov (United States)

    Reid, W R; Parker, B L; Gouli, S Y; Skinner, M; Gouli, V V; Teillon, H B

    2010-01-01

    Fungi associated with the hemlock wooly adelgid, Adelges tsugae Annand (Hemiptera: Adelgidae), were collected throughout the eastern USA and southern China. Twenty fungal genera were identified, as were 79 entomopathogenic isolates, including: Lecanicillium lecanii (Zimmermann) (Hypocreales: Insertae sedis), Isaria farinosa (Holm: Fries.) (Cordycipitaceae), Beauveria bassiana (Balasamo) (Hyphomycetes), and Fusarium spp (Nectriaceae). The remaining fungal genera associated with insect cadavers were similar for both the USA and China collections, although the abundance of Acremonium (Hypocreaceae) was greater in China. The entomopathogenic isolates were assayed for efficacy against Myzus persicae (Sulzer) (Homoptera: Aphididae) and yielded mortality ranging from 3 to 92%. Ten isolates demonstrating the highest efficacy were further assessed for efficacy against field-collected A. tsugae under laboratory conditions. Overall, two B. bassiana, one L. lecanii, and a strain of Metarhizium anisopliae (Metchnikoff) (Hypocreales: Clavicipitaceae), demonstrated significantly higher efficacy against A. tsugae than the others. Isolates were further evaluated for conidial production, germination rate and colony growth at four temperatures representative of field conditions. All isolates were determined to be mesophiles with optimal temperature between 25-30 degrees C. In general, conidial production increased with temperature, though two I. farinosa produced significantly more conidia at cooler temperatures. When efficacy values were compared with conidial production and temperature tolerances, Agricultural Research Service Collection of Entomopathogenic Fungi (ARSEF) 1080, 5170, and 5798 had characteristics comparable to the industrial B. bassiana strain GHA.

  12. Analysis of the feeding habits of the swallow-tailed hummingbird, Eupetomena macroura (Gmelin, 1788, in an urban park in southeastern Brazil

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    MCB. Toledo

    Full Text Available The aim of this work was to observe and describe the feeding habits and available food resources of the swallow-tailed hummingbird, Eupetomena macroura. The study was carried out in a municipal park located in the city of Taubaté, in the state of São Paulo. The observations took place between December 2003 and October 2004, recording the following variables: 1 the plant species visited for feeding and territorial defense; 2 the kinds of food resources; and 3 the kinds of flight to procure and obtain food. E. macroura visited 12 plant species. For territorial defense, Mangifera indica was the most visited, whereas Malvaviscus arboreus was most visited for feeding. The foliage was the plant part that received the most frequent visits. In order to obtain nectar, the only species visited was M. arboreus; to obtain arthropods, the species most visited were Mangifera indica and Hymenaea stilbocarpa. In the dry season, the hummingbirds visited flowers, whereas in the rainy season they visited leaves to acquire food. The arthropod groups most frequently found on leafy branches were Homoptera and Psocoptera. Finally, the results of the type of flight analysis showed that flight used to capture food was more often observed than were flights to search for food. In conclusion, these observations suggest that E. macroura shows plasticity in feeding behavior, which can help it to persist in urban areas.

  13. [Entomofauna associated to horticultural crops under organic and conventional practices in Córdoba, Argentina].

    Science.gov (United States)

    Zalazar, Laura; Salvo, Adriana

    2007-01-01

    Farming practices and the addition of chemical synthetic substances in conventional agroecosystems are detrimental mainly to natural enemies of phytophagous insects, diminishing the natural regulation of pest insects. On the other hand, in organic agriculture, biological processes and care of the environment are favoured, hence an increase in insect biodiversity is predicted in this type of systems. In this work, abundance, richness of insects and proportion of functional groups were compared through a single quantitative sampling of insects in horticultural crop fields, three under organic and three under conventional management practices. Insect species richness, total and for guilds (phytophagous and entomophagous insects) were significantly higher in organic orchards, and also was the abundance of entomophagous insects. Richness and abundance of all insect orders (with exception of Homoptera abundance), were higher in orchards under organic management, being significative the differences for richness of Coleoptera and richness and abundance of Hymenoptera. Similar tendencies were observed in data obtained through sweep net in weeds. These results suggest that organic practices increase the diversity of species, particularly that of natural enemies.

  14. Effects of pesticide application on arthropod pests of nursery-grown maples.

    Science.gov (United States)

    Prado, Julia; Quesada, Carlos; Sadof, Clifford

    2014-04-01

    Insecticides used against potato leafhopper, Empoasca fabae (Harris) (Homoptera: Cicadellidae), have been reported to cause problems with maple spider mite, Oligonychus aceris (Shimer) (Acarina: Tetranychidae), on nursery-grown 'Red Sunset' red maple and 'Autumn Blaze' Freeman maple. To test this, we conducted two experiments on field-grown trees in nurseries. In the first, the effects of early-season pesticide applications were examined during 2009. The second experiment was conducted in 2010 to compare effects of using threshold levels of one, three, or six leafhoppers per branch to time applications. Pesticide applications reduced abundance and damage by leafhoppers in both cultivars, but increased populations of O. aceris on Autumn Blaze during 2009. In contrast, on Red Sunset, populations of O. aceris did not increase after insecticide applications. In 2010, insecticide applications did not increase abundance of O. aceris on Autumn Blaze because use of treatment thresholds to manage leafhoppers greatly reduced numbers of trees requiring treatment for leafhoppers. Two phytoseiid mites, Neoseiulus fallacis (Garman) and Typhlodromus caudiglans (Schuster), and one stigmaeid, Zetzellia mali (Ewing), were identified as the principal predators of O. aceris on maple leaves. Insecticide applications had no significant effects on the total abundance of predatory mites on either Red Sunset or Autumn Blaze maples in 2009 or 2010. However, populations of predator Z. mali were higher during both years on Red Sunset than on Autumn Blaze. These results suggest that both early-season pesticide use and cultivar can affect the likelihood of secondary outbreaks of spider mites on maples.

  15. Habitat management of organic vineyard in Northern Italy: the role of cover plants management on arthropod functional biodiversity.

    Science.gov (United States)

    Burgio, G; Marchesini, E; Reggiani, N; Montepaone, G; Schiatti, P; Sommaggio, D

    2016-12-01

    The effect of cover plants on arthropod functional biodiversity was investigated in a vineyard in Northern Italy, through a 3-year field experiment. The following six ground cover plants were tested: Sweet Alyssum; Phacelia; Buckwheat; Faba Bean; Vetch and Oat; control. Arthropods were sampled using different techniques, including collection of leaves, vacuum sampling and sweeping net. Ground cover plant management significantly affected arthropod fauna, including beneficial groups providing ecosystem services like biological control against pests. Many beneficial groups were attracted by ground cover treatments in comparison with control, showing an aggregative numerical response in the plots managed with some of the selected plant species. Alyssum, Buckwheat and 'Vetch and Oat' mixture showed attractiveness on some Hymenoptera parasitoid families, which represented 72.3% of the insects collected by sweeping net and 45.7 by vacuum sampling. Phytoseiidae mites showed a significant increase on leaves of the vineyard plots managed with ground covers, in comparison with control, although they did not show any difference among the treatments. In general, the tested ground cover treatments did not increase dangerous Homoptera populations in comparison with control, with the exception of Alyssum. The potential of ground cover plant management in Italian vineyards is discussed: the overall lack of potential negative effects of the plants tested, combined with an aggregative numerical response for many beneficials, seems to show a potential for their use in Northern Italy vineyards.

  16. Algunos Piojos Blancos que Afectan las Plantas Cultivadas en Colombia

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    Mosquera París Felipe

    1973-12-01

    Full Text Available Debido a que en Colombia solo se habían reportado los piojos blancos de los cítricos Unaspis citri (Comstock y Pinnaspis aspidistrae (Signoret, ha existido la tendencia a llamar por uno de estos dos nombres a cualquier escama que tenga sus machos en forma de "piojo blanco". Durante el desarrollo de los reconocimientos fitosanitarios efectuados durante 1971 -1972, en colaboración con el Dr. Henry E. Martín, se encontraron varias especies de escamas (Homoptera: Diaspididae cuyos machos tenían el escudo estrecho, alargado, de bordes paralelos y recubiertos de una secreción cero él de color blanco, con un par de canales longitudinales dorsales y sus dos primeras exuvias, de color dorado, localizadas en un extremo del escudo (tipo "piojo blanco". En el presente trabajo se incluyen las principales diferencias morfológicas entre las hembras de estos insectos con anotaciones sobre sus hospederos y hábitos. Tiene por objeto además, dar alguna información sobre insectos que pueden considerarse como plagas potenciales para varios cultivos y pretende servir de ayuda para la diferenciación de las especies de "piojos blancos".

  17. Insectes ravageurs et propriétés biocides de Jatropha curcas L. (Euphorbiaceae : synthèse bibliographique

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    Abdoul Habou, Z.

    2013-01-01

    Full Text Available Insect pests and biocidal properties of Jatropha curcas L. (Euphorbiaceae. A review. Jatropha curcas is a Euphorbiaceae shrub widely distributed in many tropical countries. Its seeds are rich in oil that can be used as biofuel in modified diesel engines. Several insect species, mainly belonging to Hemiptera, Coleoptera and Orthoptera, have been referenced as insect pests of J. curcas. These insects attack the plant and cause damage to fruits, inflorescences and leaves. The most frequently observed pests belong to the genus Pachycoris (Heteroptera: Scutelleridae, which are widely distributed in Mexico, Australia, United States of America, Brazil and Nicaragua. Pachycoris spp. cause significant damage to the fruits, leading to the malformation of seeds and a reduction in their oil content. Although Jatropha shrubs are subjected to insect infestations, the oil has been shown to demonstrate biocidal activity, including insecticidal effects against several insect pests, including Busseola fusca (Fuller (Lepidoptera: Noctuidae, Sesamia calamistis Hampson (Lepidoptera: Noctuidae, Aphis gossypii Glover (Homoptera: Aphididae and Callosobruchus chinensis L. (Coleoptera: Bruchidae. In the present paper, we summarize the work carried out on inventories of J. curcas insect pests as well as on the biocidal activity of its oil.

  18. Biodiversidad del complejo de artrópodos asociados al follaje de la vegetación del norte de Chile, II región Biodiversity of the canopy arthropods associated to vegetation of the north of Chile, II region

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    FRANCISCO SAIZ

    2000-12-01

    , estableciéndose el siguiente gradiente decreciente: DL > DI > TM > TA. El contenido de cenizas de hojas y tallos también varía considerablemente y sigue el mismo patrón de variación que el contenido de agua. El contenido de nitrógeno foliar en las distintas zonas ecológicas estudiadas no varía tanto como el de agua, a excepción de TA en que son marcadamente inferiores. En cambio, en tallos es poco variable y no sigue el patrón de distribución foliar de este elemento, ni los patrones de distribución de los otros nutrientes considerados. En un enfoque global de las cuatro zonas se establece un gradiente decreciente de contenidos de agua, nitrógeno y cenizas desde el DL hasta la zona TA, concordante con el incremento en altitud, especialmente en lo referente a hojas. La familia Asteraceae muestra un definido gradiente decreciente del contenido de agua desde la costa a la alta cordillera. En cuanto al contenido foliar de cenizas difiere significativamente sólo entre DL y TM. En tallos no difiere significativamente. En total se colectaron 12.893 individuos de artrópodos asociados al follaje, distribuidos en 464 morfoespecies y 19 grupos zoológicos, considerando aparte a los antiguos Homoptera. Este grupo, junto a Hemiptera y larvas de Lepidoptera, destaca en cuanto a abundancia de especies dentro de los insectos fitófagos, así como Hymenoptera dentro de los parasitoides y Araneae entre los depredadores. En cuanto a las zonas ecológicas, el DL y TM presentan la mayor abundancia de artrópodos, tanto en especies como en individuos, así como de especies de plantas sobre las cuales se colectaron. La similaridad de la artropodofauna entre zonas ecológicas es mínima desde el punto de vista de la presencia de especies; en cambio, considerando sus abundancias, se detecta una tendencia a asociarse DI con TM y a aislarse el DL, al igual que ocurre con la vegetación. Desde el punto de vista de las diversidades específicas globales (H´ de los artrópodos se

  19. Genetic variability of the whitefly Bemisia tabaci and its secondary endosymbionts in the Arabian Peninsula

    KAUST Repository

    Ragab, Alaa I.

    2013-05-01

    The whitefly Bemisia tabaci species complex has been well documented as one of the most economically important emergent plant virus vectors, through serious feeding damage to its broad range of plant hosts and transmission of plant viruses to important agricultural crops. It has been shown to have associations with endosymbionts which have significant effects on the insect fitness. The purpose of this study was to provide information for the biotype and secondary endosymbiont distribution for B. tabaci populations in the relatively unstudied Arabian peninsula. The geographical localization and variation in endosymbiont populations across the region were identified using a sequence-driven analysis of the population genetics of the secondary endosymbiont. Live field specimens were collected from 22 different locations in the region and preserved in 70% ethanol for genetic studies. Previously established procedures were used to extract and purify total insect DNA from 24-30 individual whiteflies for each location (Frohlich et al., 1999; Chiel et al., 2007). Specimens were subjected to PCR amplification using the respective 16S rDNAprimers for the Rickettsia, Hamiltonella, and Wolbachia to amplify endosymbiont DNA. PCR was run with primers for the highly conserved whitefly mitochondrial cytochrome oxidase subunit I (COI) gene for biotyping. Samples were sequenced using the Sanger method and the data analyzed to correlate the presence, prevalence and geographical distribution of endosymbionts in B. tabaci. Phylogenies 5 were constructed to track evolutionary differences amongst the endosymbionts and insects and how they have influenced the evolution of the regional populations. Samples were characterized by differences in the genomes and endosymbionts of common whitefly ‘biotypes’ that have different host plant preferences, vector capacities and insecticide resistance characteristics. It was found that the B biotype is the predominant haplotype, with no evidence of

  20. Pyrosequencing the Bemisia tabaci transcriptome reveals a highly diverse bacterial community and a robust system for insecticide resistance.

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    Wen Xie

    Full Text Available BACKGROUND: Bemisia tabaci (Gennadius is a phloem-feeding insect poised to become one of the major insect pests in open field and greenhouse production systems throughout the world. The high level of resistance to insecticides is a main factor that hinders continued use of insecticides for suppression of B. tabaci. Despite its prevalence, little is known about B. tabaci at the genome level. To fill this gap, an invasive B. tabaci B biotype was subjected to pyrosequencing-based transcriptome analysis to identify genes and gene networks putatively involved in various physiological and toxicological processes. METHODOLOGY AND PRINCIPAL FINDINGS: Using Roche 454 pyrosequencing, 857,205 reads containing approximately 340 megabases were obtained from the B. tabaci transcriptome. De novo assembly generated 178,669 unigenes including 30,980 from insects, 17,881 from bacteria, and 129,808 from the nohit. A total of 50,835 (28.45% unigenes showed similarity to the non-redundant database in GenBank with a cut-off E-value of 10-5. Among them, 40,611 unigenes were assigned to one or more GO terms and 6,917 unigenes were assigned to 288 known pathways. De novo metatranscriptome analysis revealed highly diverse bacterial symbionts in B. tabaci, and demonstrated the host-symbiont cooperation in amino acid production. In-depth transcriptome analysis indentified putative molecular markers, and genes potentially involved in insecticide resistance and nutrient digestion. The utility of this transcriptome was validated by a thiamethoxam resistance study, in which annotated cytochrome P450 genes were significantly overexpressed in the resistant B. tabaci in comparison to its susceptible counterparts. CONCLUSIONS: This transcriptome/metatranscriptome analysis sheds light on the molecular understanding of symbiosis and insecticide resistance in an agriculturally important phloem-feeding insect pest, and lays the foundation for future functional genomics research of the

  1. Adubação e inseticidas no controle de Empoasca kraemeri e Bemisia tabaci, em cultivares de feijoeiro semeados no inverno Bean cultivars, fertilization and insecticides on the control of Empoasca kraemeri and Bemisia tabaci in the winter season

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    Arlindo Leal Boiça Jr.

    2000-12-01

    Full Text Available Vários fatores influenciam a produtividade da cultura do feijoeiro, dentre estes podem ser citados as pragas, merecendo destaque, a cigarrinha verde, Empoasca kraemeri Ross & Moore (Hemiptera: Cicadellidae e principalmente a mosca branca, Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae, que prejudica o feijoeiro pela transmissão do vírus do mosaico dourado. Este trabalho avalia o efeito de cultivares de feijoeiro, adubação e inseticidas nas populações de E. kraemeri e B. tabaci na época de semeadura "de inverno". Os genótipos utilizados foram IAPAR MD-806, IAPAR MD-808, IAC-Carioca e Bolinha. Avaliaram-se, dos 7 aos 56 dias após emergência das plantas, o número de ninfas e adultos de cigarrinha verde e mosca branca, percentual de ataque de cigarrinha e número de plantas com sintomas de mosaico dourado. Na colheita, foram avaliados o número e peso de vagens por planta, o número de grãos por planta e peso de grãos (kg ha-1. Os danos de cigarrinha verde e os sintomas de mosaico dourado foram menos intensos em IAPAR MD-806 e IAPAR MD-808 em relação ao Bolinha e IAC-Carioca. A adubação não influenciou o número médio de adultos de cigarrinha verde nos genótipos de feijoeiro. As aplicações de inseticidas e adubo proporcionaram menores números médios de adultos de mosca branca nos genótipos de feijoeiro quando avaliados em conjunto aos 56 dias após emergência das plantas.The productivity of bean crops is influenced by many factors, among them pests, in particular the leafhopper Empoasca kraemeri Ross & Moore (Hemiptera: Cicadellidae, and mainly the white fly Bemisia tabaci (Gennadius, 1889 (Hemiptera: Aleyrodidae that damages the bean crop transmitting the golden mosaic virus. The aim of the present study was to evaluate the effect of bean cultivars, chemical fertilizer and insecticides on E. kraemeri and B. tabaci populations during the winter season. The genotypes IAPAR MD-806, IAPAR MD-808, and IAC-Carioca and

  2. Whitefly population dynamics in okra plantations Dinâmica populacional de mosca-branca em quiabo

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    Germano Leão Demolin Leite

    2005-01-01

    Full Text Available The control of whitefly Bemisia tabaci (Gennadius biotype B (Hemiptera: Aleyrodidae on okra (Abelmoschus esculentus L. consists primarily in the use of insecticides, due to the lack of information on other mortality factors. The objective of this study was to evaluate the spatial and temporal population dynamics of the whitefly B. tabaci biotype B on two successive A. esculentus var. "Santa Cruz" plantations. Leaf chemical composition, leaf nitrogen and potassium contents, trichome density, canopy height, plant age, predators, parasitoids, total rainfall and median temperature were evaluated and their relationships with whitefly on okra were determined. Monthly number estimates of whitefly adults, nymphs (visual inspection and eggs (magnifying lens occurred on bottom, middle and apical parts of 30 plants/plantation (one leaf/plant. Plants senescence and natural enemies, mainly Encarsia sp., Chrysoperla spp. and Coccinellidae, were some of the factors that most contributed to whitefly reduction. The second okra plantation, 50 m apart from the first, was strongly attacked by whitefly, probably because of the insect migration from the first to the second plantation. No significant effects of the plant canopy on whitefly eggs and adults distribution were found. A higher number of whitefly nymphs was found on the medium part than on the bottom part.O controle da mosca-branca Bemisia tabaci (Gennadius biótipo B (Hemiptera: Aleyrodidae em quiabeiro (Abelmoschus esculentus L. consiste principalmente no uso de inseticidas, em virtude da falta de informação sobre outros fatores de mortalidade. O objetivo deste trabalho foi compreender a dinâmica populacional, espacial e temporal da mosca-branca em dois cultivos sucessivos de quiabeiro "Santa Cruz". Avaliaram-se a composição química foliar, os níveis foliares de nitrogênio e de potássio, a densidade de tricomas, a altura de dossel, a idade de planta, predadores, parasitóides, pluviosidade total

  3. Toxicidade do extrato aquoso das folhas de Anacardium humile para Bemisia tuberculata Toxicity of aqueous extract of Anacardium humile leaves on Bemisia tuberculata

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    Nézio Nery de Andrade Filho

    2010-08-01

    Full Text Available A mosca-branca Bemisia tuberculata (Bondar, 1923 (Hem.: Aleyrodidae é uma das principais pragas da cultura da mandioca no Estado do Mato Grosso do Sul; no entanto, não há produtos registrados para seu controle. Produtos vegetais podem constituir em alternativa viável de controle de insetos e, por sua fotodegradabilidade, diminuir os riscos ao ambiente e ao homem. Objetivou-se, por meio deste trabalho, avaliar o efeito do extrato aquoso do "cajuzinho-do-cerrado" Anacardium humile St Hill (Anacardeaceae, nas concentrações de 2,0; 0,8; 0,4 e 0,05%, sobre a biologia de B. tuberculata, bem como identificar a classe de metabólitos secundários presentes no referido extrato. O experimento foi conduzido em casa de vegetação, sob temperatura de 26±4°C. O extrato aquoso de A. humile causou aumento da duração da fase larval e mortalidade significativamente superior à testemunha em todas as concentrações testadas. Concluiu-se que o extrato aquoso de folhas de A. humile provoca mortalidade em ninfas de B. tuberculata e alongamento da fase das ninfas sobreviventes. O extrato aquoso de folhas de A. humile apresenta taninos, açúcares redutores e saponinas, e o seu índice de espuma (Índice Afrosimétrico é de 1250.The whitefly Bemisia tuberculata (Bondar, 1923 (Hem.: Aleyrodidae is the main pest of cassava crops in Mato Grosso do Sul state, however there are no products registered for its control. Plant products may represent a viable alternative for insect pest control and, due to their photo-degradability, they may reduce risks to the environment and to man. The aim of this study is to assess the effect of "cajuzinho-do-cerrado" Anacardium humile St Hill (Anacardeaceae aqueous leaf extract on the biology of B. tuberculata at the concentrations 2.0; 0.8; 0.4; 0.05%, as well as to identify the class of secondary metabolites present in the referred extract. The experiment was carried out in a greenhouse at a temperature of 26±4°C. The

  4. A fly larva (Syrphidae: Ocyptamus that preys on adult flies

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    Onanchi Ureña

    2010-12-01

    Full Text Available Predatory syrphid larvae feed on relatively immobile prey, but here we report the first case (as far as we are aware of obligatory predation on very mobile prey. Larvae of an undescribed species of Ocyptamus (Diptera: Syrphidae were found in whitefly (Hemiptera: Aleyrodidae aggregations on the undersides of citrus leaves. However, instead of preying on the whitefly nymphs (as would be expected, the larvae preyed on adult flies (Diptera that were attracted to the honeydew. In the laboratory, larvae captured significantly more flies on whitefly infested leaves than on washed leaves, and generally abandoned leaves that lacked whiteflies. Most cases of successful prey capture involved flies that probed the anterior part of the larva’s body with its proboscis (as if it were honeydew. The syrphid larva lashed out at the fly and entangled it in sticky oral secretion. The prey did not recover when they were removed from the larva, suggesting that this new predatory species also employs venom to subdue its prey. Although the larvae consumed some honeydew, they were unable to complete their development on this diet. Two parasitoids were reared from Ocyptamus puparia, Proaspicera sp. (Hymenoptera: Figitidae and Paracarotomus sp. (Hymenoptera: Pteromalidae, both of which are endoparasitic koinobionts. Rev. Biol. Trop. 58 (4: 1157-1163. Epub 2010 December 01.Las larvas depredadoras de Syrphidae se alimentan de presas relativamente inmóviles, pero aquí reportamos el primer caso (hasta ahora conocido de la depredación obligatoria en presas muy móviles. Se encontraron las larvas de una especie no descrita de Ocyptamus (Diptera: Syrphidae juntas con ninfas de mosca blanca (Hemiptera: Aleyrodidae en el envés de las hojas de cítricos. Sin embargo, en vez de alimentarse de las ninfas de mosca blanca (como debería esperarse, las larvas se alimentaron de moscas adultas (Diptera que fueron atraídas a las excreciones azucaradas de la mosca blanca. En el

  5. New Views on Strand Asymmetry in Insect Mitochondrial Genomes

    Science.gov (United States)

    Wei, Shu-Jun; Shi, Min; Chen, Xue-Xin; Sharkey, Michael J.; van Achterberg, Cornelis; Ye, Gong-Yin; He, Jun-Hua

    2010-01-01

    Strand asymmetry in nucleotide composition is a remarkable feature of animal mitochondrial genomes. Understanding the mutation processes that shape strand asymmetry is essential for comprehensive knowledge of genome evolution, demographical population history and accurate phylogenetic inference. Previous studies found that the relative contributions of different substitution types to strand asymmetry are associated with replication alone or both replication and transcription. However, the relative contributions of replication and transcription to strand asymmetry remain unclear. Here we conducted a broad survey of strand asymmetry across 120 insect mitochondrial genomes, with special reference to the correlation between the signs of skew values and replication orientation/gene direction. The results show that the sign of GC skew on entire mitochondrial genomes is reversed in all species of three distantly related families of insects, Philopteridae (Phthiraptera), Aleyrodidae (Hemiptera) and Braconidae (Hymenoptera); the replication-related elements in the A+T-rich regions of these species are inverted, confirming that reversal of strand asymmetry (GC skew) was caused by inversion of replication origin; and finally, the sign of GC skew value is associated with replication orientation but not with gene direction, while that of AT skew value varies with gene direction, replication and codon positions used in analyses. These findings show that deaminations during replication and other mutations contribute more than selection on amino acid sequences to strand compositions of G and C, and that the replication process has a stronger affect on A and T content than does transcription. Our results may contribute to genome-wide studies of replication and transcription mechanisms. PMID:20856815

  6. Trophic relationships between predators, whiteflies and their parasitoids in tomato greenhouses: a molecular approach.

    Science.gov (United States)

    Moreno-Ripoll, R; Gabarra, R; Symondson, W O C; King, R A; Agustí, N

    2012-08-01

    The whiteflies Bemisia tabaci Gennadius and Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae) are two of the main pests in tomato crops. Their biological control in Mediterranean IPM systems is based on the predators Macrolophus pygmaeus (Rambur) and Nesidiocoris tenuis Reuter (Hemiptera: Miridae), as well as on the parasitoids Eretmocerus mundus (Mercet) and Encarsia pergandiella Howard (Hymenoptera: Aphelinidae). These natural enemies may interact with each other and their joint use could interfere with the biological control of those whitefly pests. Analysis of predator-prey interactions under field conditions is therefore essential in order to optimize whitefly control. Species-specific polymerase chain reaction (PCR)-primers were designed to detect DNA fragments of these whiteflies and parasitoids within both predator species in tomato greenhouses. We demonstrated that both predators feed on both whitefly species, as well as on both parasitoids under greenhouse conditions. Prey molecular detection was possible where prey abundance was very low or even where predation was not observed under a microscope. Whitefly DNA detection was positively correlated with adult whitefly abundance in the crop. However, a significant relationship was not observed between parasitoid DNA detection and the abundance of parasitoid pupae, even though the predation rate on parasitoids was high. This unidirectional intraguild predation (predators on parasitoids) could potentially reduce their combined impact on their joint prey/host. Prey molecular detection provided improved detection of prey consumption in greenhouse crops, as well as the possibility to identify which prey species were consumed by each predator species present in the greenhouse, offering a blueprint with wider applicability to other food webs.

  7. Functional Response of Eretmocerus delhiensis on Trialeurodes vaporariorum by Parasitism and Host Feeding.

    Science.gov (United States)

    Ebrahimifar, Jafar; Jamshidnia, Arsalan; Allahyari, Hossein

    2017-01-01

    The parasitoid wasp, Eretmocerus delhiensis (Hymenoptera, Aphelinidae) is a thelytokous and syn-ovigenic parasitoid. To evaluate E. delhiensis as a biocontrol agent in greenhouse, the killing efficiency of this parasitoid by parasitism and host-feeding, were studied. Killing efficiency can be compared by estimation of functional response parameters. Laboratory experiments were performed in controllable conditions to evaluate the functional response of E. delhiensis at eight densities (2, 4, 8, 16, 32, 64, 100, and 120 third nymphal stage) of Trialeurodes vaporariorum (Hemiptera, Aleyrodidae) on two hosts including; tomato and prickly lettuce. The maximum likelihood estimates from regression logistic analysis revealed type II functional response for two host plants and the type of functional response was not affected by host plant. Roger's model was used to fit the data. The attack rate (a) for E. delhiensis was 0.0286 and 0.0144 per hour on tomato and 0.0434 and 0.0170 per hour on prickly lettuce for parasitism and host feeding, respectively. Furthermore, estimated handling times (Th) were 0.4911 and 1.4453 h on tomato and 0.5713 and 1.5001 h on prickly lettuce for parasitism and host feeding, respectively. Based on 95% confidence interval, functional response parameters were significantly different between the host plants solely in parasitism. Results of this study opens new insight in the host parasitoid interactions, subsequently needs further investigation before utilizing it for management and reduction of greenhouse whitefly. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America.

  8. Vector Transmission Alone Fails to Explain the Potato Yellow Vein Virus Epidemic among Potato Crops in Colombia.

    Science.gov (United States)

    Cuadros, Diego F; Hernandez, Anngie; Torres, Maria F; Torres, Diana M; Branscum, Adam J; Rincon, Diego F

    2017-01-01

    The potato yellow vein disease, caused by the potato yellow vein virus (PYVV), is a limiting potato disease in northern South America. The virus can be transmitted either by the greenhouse whitefly (GWF), Trialeurodes vaporariorum (Westwood) (Hemiptera: Aleyrodidae), or through vegetative propagules, such as infected tubers. Recently, GWF populations have been spotlighted as one of the main drivers of PYVV re-emergence, and consequently, PYVV management has been predominantly directed toward vector control, which is heavily based on insecticide use. However, the drivers of the PYVV outbreaks as well as the contribution of GWF populations on the spread of PYVV among potato crops are still not completely understood. This study aims to assess the role of the GWF as a driver of the PYVV epidemic in the potato-producing areas in Colombia, one of the countries more severely affected by the PYVV epidemic, and whose geography allows the study of the spatial association between the vector and the disease epidemic across a wide altitude range. The geographical clusters where the PYVV epidemic is concentrated, as well as those of farms affected by the GWF were identified using a novel spatial epidemiology approach. The influence of altitude range on the association between PYVV and T. vaporarioum was also assessed. We found a relatively poor spatial association between PYVV epidemic and the presence of the GWF, especially at altitudes above 3,000 m above mean sea level. Furthermore, GWF populations could only explain a small fraction of the extent of the PYVV epidemic in Colombia. Movement of infected seed tubers might be the main mechanism of dispersion, and could be a key driver for the PYVV infection among potato crops. Agricultural policies focused on improving quality of seed tubers and their appropriate distribution could be the most efficient control intervention against PYVV dispersion.

  9. Evaluación del efecto regulador de Chrysoperla externasobre mosca blanca Trialeurodes vaporariorum en tomate

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    Mayerly Alejandra Castro

    2016-12-01

    Full Text Available El tomate Solanum lycopersicum L es una hortaliza de gran importancia en el ámbito nacional. Dentro de las principales limitantes de este cultivo se encuentra la mosca blanca, Trialeurodes vaporariorum Westwood (Hemíptera: Aleyrodidae. Este estudio evaluó en laboratorio la capacidad reguladora de Chrysoperla externa Hagen(Neuroptera: Chrysopidae sobre mosca blanca T. vaporariorum. A partir de plantas infestadas con T. vaporariorum, se tomaron foliolos con presencia de ninfas de la plaga y se depositaron en recipientes plásticos con tapa, adicionando un individuo en cada estado larval del depredador C. externa. Se emplearon densidades de presa de 50, 75 y 100 individuos en los dos instares iniciales del depredador y 100, 150 y 200 para el tercer instar, con un testigo con 50 individuos sin depredador. Se empleó un diseño completamente al azar en condiciones de laboratorio de 17,8 °C y 67,5% de humedad relativa. Se observaron diferencias estadísticas significativas entre densidades de presa en los tres instares evaluados. Se encontró, para cada una de las densidades de presas de T. vaporariorum evaluadas en primer instar de C. externa, porcentajes de mortalidad de 96,8%, 80,5% y 56,4%, respectivamente; para el segundo instar, mortalidades de 94,4%, 77,5% y 75,4%, en su orden y para el tercer instar mortalidades de 99,1 %, 90% y 76,6%, respectivamente. De acuerdo con los resultados obtenidos, C. externa ejerce un efecto regulatorio, presentando una respuesta funcional tipo II en sus tres instares larvales, cuando actúa como depredador de ninfas de T. vaporariorum.

  10. Volatile-Mediated Attraction of Greenhouse Whitefly Trialeurodes vaporariorum to Tomato and Eggplant

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    Hewa L. C. Darshanee

    2017-07-01

    Full Text Available The behavior of the greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae, is known to be affected by plant volatile cues, but its attraction or repellent to specific volatile cues has not been deeply studied yet. Therefore, the aim of our study was to identify the most attractive plant among cultivars of tomato (Solanum lycopersicum and eggplant (Solanum melongena to evaluate the volatiles of plants to identify the chemical compound(s that attract T. vaporariorum. We speculated that whitefly–host plant interaction primarily depends on plant volatile emissions and that once the plant is damaged, it might attract more whiteflies. Three intact (uninfested tomato, four intact eggplant cultivars and whitefly infested plants of the most whitefly attractive tomato and eggplant cultivars were examined by behavioral assay experiments for attractiveness to T. vaporariorum and headspace volatile were determined by solid-phase microextraction (SPME and gas chromatography-mass spectrometry. Whiteflies had the highest preference for the intact eggplant Kuai Yuan Qie (KYQ among the eggplant and the tomato plant cultivars in bioassay experiments. Although both male and female whiteflies were significantly more attracted to infested KYQ plants than to intact plants, whitefly females did not select conspecific-infested YG plants. The volatile emissions among different plant cultivars in individual species and infested versus intact plants were significantly different. Among these volatiles, identified major green leaf volatiles [(Z-3-hexen-1-ol] and terpenoids [α-pinene, (E-β-caryophyllene, α-humulene, azulene] showed a constitutive relationship with the most whitefly preference plants. Our findings provide new insights into the chemical compounds that attract or repel whiteflies.

  11. Dissemination of Aleurocanthus woglumi in citrus plants, its natural enemies and new host plants in the state of Rio de Janeiro, Brazil

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    Rodrigo Garcia Alvim

    Full Text Available ABSTRACT: Aleurocanthus woglumi is an exotic pest, widely disseminated in Brazil, with a high preference for citrus plants, but with a polyphagous feeding habit. The contribution of the state of Rio de Janeiro in the Brazilian production of citrus fruits is small; however, there are still public policies that encourage citrus production in the state. In 2010, the appearance of this pest in Rio de Janeiro was confirmed in the municipality of Cachoeiras de Macacu. The objectives of this research were to evaluate the dissemination of A. woglumi in this state, conduct a survey of new species of host plants, identify and evaluate the population of natural enemies present at two orchards that grow 'Tahiti' limes ( Citrus latifolia infested by the pest in Cachoeiras de Macacu, RJ, Brazil. In 19 municipalities, leaves of citrus and other species of plants presenting aleyrodid nymphs were collected, and yellow sticky traps were installed to capture adults for subsequent identification. At the 'Tahiti' lime orchards, the leaf collections were done to confirm the species of Aleyrodidae , and regarding A. woglumi , the natural enemies associated with this pest were collected directly from the infested plants. The results showed that A. woglumi is wide-spread in 12 municipalities. Three new host plants for A. woglumi were identified: Artocarpus heterophyllus ( Moraceae , Pouteria caimito ( Sapotaceae and Struthanthus flexicaulis ( Loranthaceae . In Cachoeiras de Macacu, a new species of parasitoid of A. woglumi nymphs was named: Encarsia pergandiella (Hymenoptera: Aphelinidae , while the insects in the Coccinellidae (Coleoptera family have stood out as predators of this pest.

  12. Eficacia de diferentes diodos emisores de luz (LEDs unidos a trampas adhesivas amarillas para la captura de la mosca blanca Trialeurodes vaporariorum

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    Jorge Eduardo Castresana

    2015-12-01

    Full Text Available Teniendo en cuenta que algunos adultos de insectos muestran preferencia a ciertas longitudes de onda, se ha considerado este comportamiento para desarrollar herramientas de monitoreo y estrategias de control de insectos plaga. Como ejemplo de ello, las tarjetas adhesivas amarillas han sido ampliamente usadas para monitorear población de moscas blancas a campo como invernadero. Este estudio tuvo como objetivo evaluar la efectividad de trampas adhesivas amarillas provistas con luces emitidas por diodos (LEDs para el trampeo de adultos moscas blancas Trialeurodes vaporariorum (Westwood (Hemiptera: Aleyrodidae. Los ensayos se llevaron a cabo en la EEA INTA Concordia en condiciones de umbráculo, donde se ubicaron jaulas de cría con plantas de tabaco, Solanum tabacum (L. y poroto, Phaseolus vulgaris (L. desde Junio hasta Julio del 2013. Las trampas adhesivas amarillas tuvieron una superficie de 64cm2 provistas con (LEDs de diferentes longitudes de onda promedio (525 nm verde y 380 nm UV y sin LED como testigo. Los ensayos mostraron que los adultos de mosca blanca fueron significativamente (α >0.05 más atraídos por las trampas equipadas con LED 525 nm verde (134 ± 7.4 adultos/tarjeta comparadas con trampas equipadas con LED 380 nm UV (105 ± 7.4 adultos/tarjeta y trampas sin LED (85.17 ± 7.4 adultos/tarjeta. Estos resultados muestran que los adultos de T. vaporariorum son atraídos a trampas dotadas con LED verde, las cuales podrían tener un promisorio uso en invernadero como detección, monitoreo y control de mosca blanca.

  13. Preference and Prey Switching in a Generalist Predator Attacking Local and Invasive Alien Pests

    Science.gov (United States)

    Jaworski, Coline C.; Bompard, Anaïs; Genies, Laure; Amiens-Desneux, Edwige; Desneux, Nicolas

    2013-01-01

    Invasive pest species may strongly affect biotic interactions in agro-ecosystems. The ability of generalist predators to prey on new invasive pests may result in drastic changes in the population dynamics of local pest species owing to predator-mediated indirect interactions among prey. On a short time scale, the nature and strength of such indirect interactions depend largely on preferences between prey and on predator behavior patterns. Under laboratory conditions we evaluated the prey preference of the generalist predator Macrolophus pygmaeus Rambur (Heteroptera: Miridae) when it encounters simultaneously the local tomato pest Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) and the invasive alien pest Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae). We tested various ratios of local vs. alien prey numbers, measuring switching by the predator from one prey to the other, and assessing what conditions (e.g. prey species abundance and prey development stage) may favor such prey switching. The total predation activity of M. pygmaeus was affected by the presence of T. absoluta in the prey complex with an opposite effect when comparing adult and juvenile predators. The predator showed similar preference toward T. absoluta eggs and B. tabaci nymphs, but T. absoluta larvae were clearly less attacked. However, prey preference strongly depended on prey relative abundance with a disproportionately high predation on the most abundant prey and disproportionately low predation on the rarest prey. Together with the findings of a recent companion study (Bompard et al. 2013, Population Ecology), the insight obtained on M. pygmaeus prey switching may be useful for Integrated Pest Management in tomato crops, notably for optimal simultaneous management of B. tabaci and T. absoluta, which very frequently co-occur on tomato. PMID:24312646

  14. Preference and prey switching in a generalist predator attacking local and invasive alien pests.

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    Coline C Jaworski

    Full Text Available Invasive pest species may strongly affect biotic interactions in agro-ecosystems. The ability of generalist predators to prey on new invasive pests may result in drastic changes in the population dynamics of local pest species owing to predator-mediated indirect interactions among prey. On a short time scale, the nature and strength of such indirect interactions depend largely on preferences between prey and on predator behavior patterns. Under laboratory conditions we evaluated the prey preference of the generalist predator Macrolophus pygmaeus Rambur (Heteroptera: Miridae when it encounters simultaneously the local tomato pest Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae and the invasive alien pest Tuta absoluta (Meyrick (Lepidoptera: Gelechiidae. We tested various ratios of local vs. alien prey numbers, measuring switching by the predator from one prey to the other, and assessing what conditions (e.g. prey species abundance and prey development stage may favor such prey switching. The total predation activity of M. pygmaeus was affected by the presence of T. absoluta in the prey complex with an opposite effect when comparing adult and juvenile predators. The predator showed similar preference toward T. absoluta eggs and B. tabaci nymphs, but T. absoluta larvae were clearly less attacked. However, prey preference strongly depended on prey relative abundance with a disproportionately high predation on the most abundant prey and disproportionately low predation on the rarest prey. Together with the findings of a recent companion study (Bompard et al. 2013, Population Ecology, the insight obtained on M. pygmaeus prey switching may be useful for Integrated Pest Management in tomato crops, notably for optimal simultaneous management of B. tabaci and T. absoluta, which very frequently co-occur on tomato.

  15. Validation of a Landscape-Based Model for Whitefly Spread of the Cucurbit Yellow Stunting Disorder Virus to Fall Melons.

    Science.gov (United States)

    Carrière, Yves; Degain, Ben; Liesner, Leighton; Dutilleul, Pierre; Palumbo, John C

    2017-10-01

    The cucurbit yellow stunting disorder virus (CYSDV) transmitted by Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) has caused significant reductions in fall melon (Cucumis melo L.) yields in Yuma County, Arizona. In a recent landscape-based study, we found evidence that cotton and spring melon fields increased abundance of B. tabaci and spread of CYSDV infection in fall melon fields. Here, we show that a statistical model derived from data collected in 2011-2012 and based on areas of cotton and spring melon fields located within 1,500 m from edges of fall melon fields was sufficient to retrospectively predict incidence of CYSDV infection in fall melon fields during 2007-2010. Nevertheless, the slope of the association between areas of spring melon fields and incidence of CYSDV infection was three times smaller in 2007-2010 than in 2011-2012, whereas the slope of the association between areas of cotton fields and incidence of CYSDV infection was consistent between study periods. Accordingly, predictions were more accurate when data on areas of cotton alone were used as a basis for prediction than when data on areas of cotton and spring melons were used. Validation of this statistical model confirms that crop isolation has potential for reducing incidence of CYSDV infection in fall melon fields in Yuma County, although isolation from cotton may provide more consistent benefits than isolation from spring melon. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Volatile-Mediated Attraction of Greenhouse Whitefly Trialeurodes vaporariorum to Tomato and Eggplant

    Science.gov (United States)

    Darshanee, Hewa L. C.; Ren, Hui; Ahmed, Nazeer; Zhang, Zhan-Feng; Liu, Yan-Hong; Liu, Tong-Xian

    2017-01-01

    The behavior of the greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hemiptera: Aleyrodidae), is known to be affected by plant volatile cues, but its attraction or repellent to specific volatile cues has not been deeply studied yet. Therefore, the aim of our study was to identify the most attractive plant among cultivars of tomato (Solanum lycopersicum) and eggplant (Solanum melongena) to evaluate the volatiles of plants to identify the chemical compound(s) that attract T. vaporariorum. We speculated that whitefly–host plant interaction primarily depends on plant volatile emissions and that once the plant is damaged, it might attract more whiteflies. Three intact (uninfested) tomato, four intact eggplant cultivars and whitefly infested plants of the most whitefly attractive tomato and eggplant cultivars were examined by behavioral assay experiments for attractiveness to T. vaporariorum and headspace volatile were determined by solid-phase microextraction (SPME) and gas chromatography-mass spectrometry. Whiteflies had the highest preference for the intact eggplant Kuai Yuan Qie (KYQ) among the eggplant and the tomato plant cultivars in bioassay experiments. Although both male and female whiteflies were significantly more attracted to infested KYQ plants than to intact plants, whitefly females did not select conspecific-infested YG plants. The volatile emissions among different plant cultivars in individual species and infested versus intact plants were significantly different. Among these volatiles, identified major green leaf volatiles [(Z)-3-hexen-1-ol] and terpenoids [α-pinene, (E)-β-caryophyllene, α-humulene, azulene] showed a constitutive relationship with the most whitefly preference plants. Our findings provide new insights into the chemical compounds that attract or repel whiteflies. PMID:28775733

  17. New views on strand asymmetry in insect mitochondrial genomes.

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    Shu-Jun Wei

    Full Text Available Strand asymmetry in nucleotide composition is a remarkable feature of animal mitochondrial genomes. Understanding the mutation processes that shape strand asymmetry is essential for comprehensive knowledge of genome evolution, demographical population history and accurate phylogenetic inference. Previous studies found that the relative contributions of different substitution types to strand asymmetry are associated with replication alone or both replication and transcription. However, the relative contributions of replication and transcription to strand asymmetry remain unclear. Here we conducted a broad survey of strand asymmetry across 120 insect mitochondrial genomes, with special reference to the correlation between the signs of skew values and replication orientation/gene direction. The results show that the sign of GC skew on entire mitochondrial genomes is reversed in all species of three distantly related families of insects, Philopteridae (Phthiraptera, Aleyrodidae (Hemiptera and Braconidae (Hymenoptera; the replication-related elements in the A+T-rich regions of these species are inverted, confirming that reversal of strand asymmetry (GC skew was caused by inversion of replication origin; and finally, the sign of GC skew value is associated with replication orientation but not with gene direction, while that of AT skew value varies with gene direction, replication and codon positions used in analyses. These findings show that deaminations during replication and other mutations contribute more than selection on amino acid sequences to strand compositions of G and C, and that the replication process has a stronger affect on A and T content than does transcription. Our results may contribute to genome-wide studies of replication and transcription mechanisms.

  18. Plano de amostragem do biótipo B de Bemisia tabaci na cultura do pepino

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    Moura Marcelo Fialho de

    2003-01-01

    Full Text Available A adoção de programas de manejo integrado de pragas permite reduzir a aplicação de inseticidas e os planos convencionais de amostragem representam o ponto inicial na geração desses programas. Assim, o objetivo deste trabalho foi determinar plano de amostragem convencional para o biótipo B da mosca-branca Bemisia tabaci Genn. (Hemiptera: Aleyrodidae na cultura do pepino. Foram avaliadas as densidades de ninfas e de adultos em dez lavouras comerciais de pepino, Tocantins, MG, estudando nove sistemas amostrais formados pela combinação de três técnicas (batida de folha em bandeja de plástico branco, contagem direta dos insetos na face inferior da folha e coleta de folha em sacola de plástico e três unidades amostrais (folha do terço apical, mediano ou basal do espaldeiramento. A contagem direta em folha do terço basal foi o sistema com maior precisão econômica na amostragem de ninfas, mas não possibilitou a geração de plano de amostragem praticável. As batidas, em bandeja, de folha dos terços apicais, medianos ou basais do espaldeiramento foram os sistemas economicamente mais precisos na amostragem de adultos. Desses, apenas a batida de folha do terço mediano em bandeja gerou plano de amostragem praticável, sendo que este plano é composto de 196 amostras/lavoura.

  19. Prey Preference and Life Table of Amblyseius orientalis on Bemisia tabaci and Tetranychus cinnabarinus.

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    Xiaoxiao Zhang

    Full Text Available Amblyseius orientalis (Ehara (Acari: Phytoseiidae is a native predatory mite species in China. It used to be considered as a specialist predator of spider mites. However, recent studies show it also preys on other small arthropod pests, such as Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae. Experiments were conducted to investigate (1 prey preference of A. orientalis between Tetranychus cinnabarinus (Boisd. (Acari: Tetranychidae and B. tabaci, and (2 development, consumption and life table parameters of A. orientalis when reared on T. cinnabarinus, B. tabaci or a mix of both prey species. When preying on different stages of T. cinnabarinus, A. orientalis preferred protonymphs, whereas when preying on different stages of B. tabaci, A. orientalis preferred eggs. When these two most preferred stages were provided together (T. cinnabarinus protonymphs and B. tabaci eggs, A. orientalis randomly selected its prey. Amblyseius orientalis was able to complete its life cycle on B. tabaci eggs, T. cinnabarinus protonymphs, or a mix of both prey. However, its developmental duration was 53.9% and 30.0% longer when reared on B. tabaci eggs than on T. cinnabarinus and a mix of both prey, respectively. In addition, it produced only a few eggs and its intrinsic rate of increase was negative when reared on B. tabaci eggs, which indicates that B. tabaci is not sufficient to maintain A. orientalis population. The intrinsic rates of increase were 0.16 and 0.23 when A. orientalis was fed on the prey mix and T. cinnabarinus, respectively. These results suggest that although B. tabaci is a poor food resource for A. orientalis in comparison to T. cinnabarinus, A. orientalis is able to sustain its population on a mix of both prey. This predatory mite may thus be a potential biological control agent of B. tabaci when this pest co-occurs with the alternative minor pest T. cinnabarinus.

  20. Insetos indutores de galhas da porção sul da Cadeia do Espinhaço, Minas Gerais, Brasil Gall inducing insects from southern portion of the Espinhaço Range, Minas Gerais, Brazil

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    Marco Antonio A. Carneiro

    2009-12-01

    Full Text Available A riqueza de insetos galhadores é maior nas latitudes intermediárias em hábitats quentes e com vegetação esclerófila sob estresse hídrico e de nutrientes. Em regiões tropicais, os campos rupestres são indicados como hábitats ricos em espécies de insetos galhadores. Neste trabalho, foram descritas as galhas induzidas por insetos e suas plantas hospedeiras na porção sul da Cadeia do Espinhaço, sudeste do Brasil. Foram selecionados 60 sítios em seis regiões ao longo na porção sul da Cadeia do Espinhaço no estado de Minas Gerais. Em cada sítio 100 plantas foram amostradas totalizando 6.000 plantas censuradas ao longo de um gradiente altitudinal de 668 a 1860m. Foram encontrados 241 morfotipos de galhas em 142 espécies de plantas distribuídas em 29 famílias e de um total de 384 espécies de plantas amostradas. As famílias mais ricas em espécies de insetos galhadores foram Asteraceae (42%, principalmente espécies do gênero Baccharis. A maior parte das galhas (85% foi induzida por insetos da família Cecidomyiidae seguidos por Lepidoptera (4% e Homoptera (3%. Os ramos foram os órgãos mais freqüentemente atacados (72% enquanto que os morfotipos mais comuns foram o elíptico (37% e o globóide (36%. A espécie de planta hospedeira que apresentou mais morfotipos de galhas foi Baccharis pseudomyriocephala com 10 galhas distintas. Este estudo sustenta a afirmativa que campos rupestres apresentam uma elevada riqueza em espécies de insetos galhadores.Galling species richness is higher at intermediate latitudes on warm habitats and sclerophyllous vegetation under water and nutrient stress. In the tropical region, galling species richness is higher in rupestrian fields. Here the gall-inducing insects and their host plants of the southern portion of the Espinhaço range, southeastern Brazil are described. 60 study sites from six distinct regions along the Espinhaço range, at Minas Gerais state were selected. In each study site 100

  1. Shallot Aphids, Myzus ascalonicus, in Strawberry: Biocontrol Potential of Three Predators and Three Parasitoids

    Science.gov (United States)

    Enkegaard, Annie; Sigsgaard, Lene; Kristensen, Kristian

    2013-01-01

    The parasitization capacity of 3 parasitoids and the predation capacity of 3 predators towards the shallot aphid, Myzus ascalonicus Doncaster (Homoptera: Aphididae), on strawberry, Fragaria x ananassa Duchesne (Rosales: Rosaceae) cv. Honeoye, were examined in laboratory experiments. In Petri dish assays, both Aphidius colemani Viereck (Hymenoptera: Aphidiidae) and A. ervi Haliday readily stung shallot aphids, with no significant difference in stinging frequency between the two species. A. ervi induced a significantly higher mortality (79.0 ± 7.2%) in terms of stung aphids compared with A. colemani (55.3 ± 4.1%); however, only a minor fraction (2.7 ± 1.8% and 7.1 ± 3.1%, respectively) of the killed aphids resulted in formation of mummies, presumably due to a physiological response to parasitism. The low percentage of mummification precludes the use of either Aphidius species in anything but inundative biocontrol. In similar set-ups, Aphelinus abdominalis (Dalman) (Hymenoptera: Aphelinidae) killed almost half (49.6 ± 5.3%) of the exposed aphids through host feeding. In addition, 23.2 ± 7.3% of non-host-fed aphids developed into mummified aphids, and 38.1 ± 13.2% of non-host-fed aphids died from other parasitoid-induced causes. However, the host feeding rate was reduced to only 1.2 ± 0.8%, and no significant parasitization mortality was observed on strawberry plants, suggesting that host plants interfered with A. abdominalis activity. This parasitoid does not, therefore, seem to be suited to either inoculative or inundative biocontrol of shallot aphids in strawberry. The three predators studied were the green lacewing, Chrysoperla carnea Steph. (Neuroptera: Chrysopidae), the two-spotted lady beetle, Adalia bipunctata L. (Coleoptera: Coccinellidae), and the gall midge Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae). Third instars of all 3 predators readily preyed upon the shallot aphid in Petri dish set-ups with significant differences in daily

  2. Shallot aphids, Myzus ascalonicus, in strawberry: biocontrol potential of three predators and three parasitoids.

    Science.gov (United States)

    Enkegaard, Annie; Sigsgaard, Lene; Kristensen, Kristian

    2013-01-01

    The parasitization capacity of 3 parasitoids and the predation capacity of 3 predators towards the shallot aphid, Myzus ascalonicus Doncaster (Homoptera: Aphididae), on strawberry, Fragaria x ananassa Duchesne (Rosales: Rosaceae) cv. Honeoye, were examined in laboratory experiments. In Petri dish assays, both Aphidius colemani Viereck (Hymenoptera: Aphidiidae) and A. ervi Haliday readily stung shallot aphids, with no significant difference in stinging frequency between the two species. A. ervi induced a significantly higher mortality (79.0 ± 7.2%) in terms of stung aphids compared with A. colemani (55.3 ± 4.1%); however, only a minor fraction (2.7 ± 1.8% and 7.1 ± 3.1%, respectively) of the killed aphids resulted in formation of mummies, presumably due to a physiological response to parasitism. The low percentage of mummification precludes the use of either Aphidius species in anything but inundative biocontrol. In similar set-ups, Aphelinus abdominalis (Dalman) (Hymenoptera: Aphelinidae) killed almost half (49.6 ± 5.3%) of the exposed aphids through host feeding. In addition, 23.2 ± 7.3% of non-host-fed aphids developed into mummified aphids, and 38.1 ± 13.2% of non-host-fed aphids died from other parasitoid-induced causes. However, the host feeding rate was reduced to only 1.2 ± 0.8%, and no significant parasitization mortality was observed on strawberry plants, suggesting that host plants interfered with A. abdominalis activity. This parasitoid does not, therefore, seem to be suited to either inoculative or inundative biocontrol of shallot aphids in strawberry. The three predators studied were the green lacewing, Chrysoperla carnea Steph. (Neuroptera: Chrysopidae), the two-spotted lady beetle, Adalia bipunctata L. (Coleoptera: Coccinellidae), and the gall midge Aphidoletes aphidimyza (Rondani) (Diptera: Cecidomyiidae). Third instars of all 3 predators readily preyed upon the shallot aphid in Petri dish set-ups with significant differences in daily

  3. Richness and composition of gall-inducing arthropods at Coiba National Park, Panama

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    José Luis Nieves-Aldrey

    2008-09-01

    Full Text Available Interest in studying galls and their arthropods inducers has been growing rapidly in the last two decades. However, the Neotropical region is probably the least studied region for gall-inducing arthropods. A study of the richness and composition of gall-inducing arthropods was carried out at Coiba National Park in the Republic of Panama. Field data come from samples obtained between August 1997 and September 1999, with three (two-week long more intensive samplings. Seventeen sites, representing the main land habitats of Coiba National Park were surveyed. 4942 galls of 50 insect and 9 mite species inducing galls on 50 vascular plants from 30 botanical families were colleted. 62.7% of the galls were induced by gall midges (Diptera, Cecidomyiidae, 15.3% by mites, Eriophyidae, 8.5% by Homoptera, Psyllidae, 6.8% by Coccidae and 5.1% by Phlaeothripidae (Tysanoptera. The host plant families with the most galls were Myrtaceae with seven, Bignoniaceae with five and Euphorbiaceae, Fabaceae and Melastomataceae with four. Leaf galls accounted for about 93% of collected galls. Most leaf galls were pit/blister galls followed by covering and pouch galls. Gall richness per collecting site was between 1 and 19 species. Coiba’s gall diversity is discussed in relation to data available from other tropical sites from continental Panama and the Neotropical region. Our results support the idea that it may be premature to conclude that species richness of gall inducers declines near the equator. Rev. Biol. Trop. 56 (3: 1269-1286. Epub 2008 September 30.El interés por el estudio de las agallas y los artrópodos que las inducen ha crecido en todo el mundo en los últimos veinte años. Sin embargo, los artrópodos que inducen agallas en la región Neotropical son probablemente los menos estudiados. Un estudio de la riqueza y composición de artrópodos que inducen agallas fue desarrollado en el Parque Nacional Coiba en la Republica de Panamá. Los datos provienen de

  4. Alimentação e fator de condição de peixes characidiíneos no sistema do Ribeirão Grande, Sudeste do Brasil - DOI: 10.4025/actascibiolsci.v27i3.1336 Feeding and condition factor of characidiin fish in Ribeirão Grande system, Southeastern Brazil - DOI: 10.4025/actascibiolsci.v27i3.1336

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    Francisco Manoel de Souza Braga

    2005-03-01

    Full Text Available Os peixes foram amostrados quatro vezes em cada local, de julho de 2001 a abril de 2002: inverno (julho de 2001, primavera (outubro de 2001, verão (fevereiro de 2002 e outono (abril de 2002. Foram amostrados segmentos de cinco riachos no sistema do Ribeirão Grande (22o 47’ 08’’ S, 45o 28’ 17’’W. Coletas quantitativas foram feitas com um aparelho de pesca-elétrica ligado a um gerador com capacidade máxima de 1.500 V e 8,7 A de 600 Hz de corrente alternada. Alimentação, mudanças na gordura visceral e fator de condição foram comparados em duas espécies de characidiíneos, Characidium lauroi e C. Alipioi do sistema do Ribeirão Grande, sudeste do Brasil. Nas dietas das duas espécies ninfas de Ephemeroptera, foram registradas larvas de Diptera (Chironomidae, Simuliidae, ninfas de Plecoptera, larvas de Trichoptera (Hydroptilidae, Psychoyiidae, insetos terrestres (Coleoptera, Isoptera, Hemiptera [Heteroptera, Homoptera], larvas de Megaloptera (Corydalidae, Arachnida, Ostracoda e restos vegetais. A gordura visceral decresceu em fevereiro, coincidindo com o declínio do fator de condição em ambas as espécies. O aumento da atividade alimentar durante o verão proporciona o acúmulo de gordura. Durante as estações seguintes, esses peixes devem utilizar as reservas de gordura visceral para manutenção e reproduçãoFeeding, seasonal changes in visceral fat and condition factor were compared in two species of characidiin fishes, Characidium lauroi and C. alipioi from Ribeirão Grande system, southeastern Brazil. Five streams of Ribeirão Grande system were sampled (22o 47’ 08’’ S, 45o 28’ 17’’W. The samples were taken four times per site, from July, 2001 to April, 2002: winter (July 2001, spring (October 2001, summer (February 2002 and autumn (April 2002. Quantitative collections were made with an electro-fishing device powered by a generator with maximum capacity of 1,500 V and 8.7 A of 60 Hz alternating current

  5. Introduced and invasive insect species in the Czech Republic and their economic and ecological impact (Insecta

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    Hana Šefrová

    2005-01-01

    Full Text Available A total of 383 alien insect species were registered in the Czech Republic, which represents 1.4% of local fauna. The most numerous taxonomic groups are Homoptera (116 species, 30.3%, Coleoptera (110; 28.7% and Lepidoptera (37; 9.7%. The occurrence of 200 species (52.2% are limited to closed heated spaces, casual aliens (28; 7.3% infiltrate the outdoor environment for a short term only, 36 (9.4% naturalized non-invasive species do not spread from the location of introduction, 50 (13.1% species are post-invasive and 69 (18.0% invasive. From the species registered, 61 (15.9% are stored product pests (especially Coleoptera 36 species, Psocoptera 11, and Lepidoptera 9, 50 (13.1% are plant pests indoors (especially Coccinea 33 species, Aphidinea 7, and Thysanoptera 6, 25 (i.e. 6.5% of aliens are pests in agriculture, forestry, and in ornamental cultures, 15 species (3.9% are important animal parasites, and 5 species (1.3% can affect biodiversity. Of the remaining 227 species (59.3%, no economic or ecological effects were found. The origin of most of the species living eusynanthropically is in the tropics and subtropics; of the 155 naturalized (non-invasive, post-invasive, and invasive species, 42 (27.1% originate from the Mediterranean, 36 (23.2% from North America, 28 (18.1% from Central to Southwest Asia, 14 (9.0% from East Asia, 13 (8.4% from South and Southeast Asia, with the remaining 22 species (14.2% coming from other areas.

  6. Phytoplasma infection of a tropical root crop triggers bottom-up cascades by favoring generalist over specialist herbivores.

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    Kris A G Wyckhuys

    Full Text Available Global interest on plant-microbe-insect interactions is rapidly growing, revealing the multiple ways in which microorganisms mediate plant-herbivore interactions. Phytopathogens regularly alter whole repertoires of plant phenotypic traits, and bring about shifts in key chemical or morphological characteristics of plant hosts. Pathogens can also cause cascading effects on higher trophic levels, and eventually shape entire plant-associated arthropod communities. We tested the hypothesis that a Candidatus Phytoplasma causing cassava witches' broom (CWB on cassava (Manihot esculenta Grantz is altering species composition of invasive herbivores and their associated parasitic hymenopterans. We conducted observational studies in cassava fields in eastern Cambodia to assess the effect of CWB infection on abundance of specialist and generalist mealybugs (Homoptera: Pseudococcidae, and associated primary and hyper-parasitoid species. CWB infection positively affects overall mealybug abundance and species richness at a plant- and field-level, and disproportionately favors a generalist mealybug over a specialist feeder. CWB phytoplasma infection led to increased parasitoid richness and diversity, with richness of 'comparative' specialist taxa being the most significantly affected. Parasitism rate did not differ among infected and uninfected plants, and mealybug host suppression was not impacted. CWB phytoplasma modifies host plant quality for sap-feeding homopterans, differentially affects success rates of two invasive species, and generates niche opportunities for higher trophic orders. By doing so, a Candidatus phytoplasma affects broader food web structure and functioning, and assumes the role of an ecosystem engineer. Our work unveils key facets of phytoplasma ecology, and sheds light upon complex multi-trophic interactions mediated by an emerging phytopathogen. These findings have further implications for invasion ecology and management.

  7. ASSESSING OF HERBIVOROUS AND BENEFICIAL INSECTS ON SWITCHGRASS IN UKRAINE.

    Science.gov (United States)

    Stefanovska, T; Kucherovska, S; Pisdlisnyuk, V

    2014-01-01

    A perennial switchgrass, (Panicum virgatum L.), (C4) that is native to North America has good potential for biomass production because of its wide geographic distribution and adaptability to diverse environmental conditions. Insects can significantly impact the yield and quality of biofuel crops. If switchgrass are to be grown on marginally arable land or in monoculture, it are likely to be plagued with herbivore pests and plant diseases at a rate that exceeds what would be expected if the plants were not stressed in this manner. This biofuel crop has been under evaluation for commercial growing in Ukraine for eight years. However, insect diversity and the potential impact of pests on biomass production of this feedstock have not been accessed yet. The objective of our study, started in 2011, is a survey of switch grass insects by trophic groups and determine species that have pest status at two sites in the Central part of Ukraine (Kiev and Poltava regions). In Poltava site we investigated the effect of nine varieties of switchgrass (lowland and upland) to insects' diversity. We assessed changes over time in the densities of major insects' trophic groups, identifying potential pests and natural enemies. Obtained results indicates that different life stages of herbivorous insects from Hymenoptera, Homoptera, Diptera and Coleoptera orders were present on switchgrass during the growing season. Our study results suggests that choice of variety has an impact on trophic groups' structure and number of insects from different orders on swicthgrass. Herbivores and beneficial insects were the only groups that showed significant differences across sampling dates. The highest population of herbivores insects we recorded on 'Alamo' variety for studied years, although herbivore diversity tended to increase on 'Shelter', 'Alamo' and 'Cave-in-Rock' during 2012 and 2013. 'Dacotah', 'Nebraska', 'Sunburst', 'Forestburg' and 'Carthage' showed the highest level of beneficial insects

  8. Rapid detection of vip1-type genes from Bacillus cereus and characterization of a novel vip binary toxin gene.

    Science.gov (United States)

    Yu, Xiumei; Liu, Tao; Liang, Xiaoxing; Tang, Changqing; Zhu, Jun; Wang, Shiquan; Li, Shuangcheng; Deng, Qiming; Wang, Linxia; Zheng, Aiping; Li, Ping

    2011-12-01

    A PCR-restriction fragment length polymorphism (PCR-RFLP) method for identifying vegetative insecticidal protein (vip) 1-type genes from Bacillus cereus was developed by designing specific primers based on the conserved regions of the genes to amplify vip1-type gene fragments. PCR products were digested with endonuclease AciI, and four known vip1-type genes were identified. Vip1Ac and vip1Aa-type genes appeared in 17 of 26 B. cereus strains. A novel vip1-type gene, vip1Ac1, was identified from B. cereus strain HL12. The vip1Ac1 and vip2Ae3 genes were co-expressed in Escherichia coli strain BL21 by vector pCOLADuet-1. The binary toxin showed activity only against Aphis gossypii (Homoptera), but not for Coleptera (Tenebrio molitor, Holotrichia oblita), Lepidoptera (Spodoptera exigua, Helicoverpa armigera, and Chilo suppressalis), Diptera (Culex quinquefasciatus). The LC(50) of this binary toxin for A. gossypii is 87.5 (34.2-145.3) ng mL(-1) . This is probably only the second report that Vip1 and Vip2 binary toxin shows toxicity against homopteran pests. The PCR-RFLP method developed could be very useful for identifying novel Vip1-Vip2-type binary toxins, and the novel binary toxins, Vip1Ac1 and Vip2Ae3, identified in this study may have applications in biological control of insects, thus avoiding potential problems of resistance. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  9. Evaluation of airborne methyl salicylate for improved conservation biological control of two-spotted spider mite and hop aphid in Oregon hop yards.

    Science.gov (United States)

    Woods, J L; James, D G; Lee, J C; Gent, D H

    2011-12-01

    The use of synthetic herbivore-induced plant volatiles (HIPV) to attract natural enemies has received interest as a tool to enhance conservation biological control (CBC). Methyl salicylate (MeSA) is a HIPV that is attractive to several key predators of two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), and hop aphid, Phorodon humuli (Schrank) (Homoptera: Aphididae). A 2-year study was conducted to evaluate the recommended commercial use of MeSA in hop yards in Oregon. Slow-release MeSA dispensers were stapled to supporting poles in 0.5 ha plots and these plots were compared to a paired non-treated plot on each of three farms in 2008 and 2009. Across both years, there was a trend for reduced (range 40-91%) mean seasonal numbers of T. urticae in five of the six MeSA-baited plots. Stethorus spp., key spider mite predators, tended to be more numerous in MeSA-baited plots compared to control plots on a given farm. Mean seasonal densities of hop aphid and other natural enemies (e.g., Orius spp. and Anystis spp.) were similar between MeSA-treated and control plots. Variability among farms in suppression of two-spotted spider mites and attraction of Stethorus spp. suggests that the use of MeSA to enhance CBC of spider mites in commercial hop yards may be influenced by site-specific factors related to the agroecology of individual farms or seasonal effects that require further investigation. The current study also suggests that CBC of hop aphid with MeSA in this environment may be unsatisfactory.

  10. Phytoplasma infection of a tropical root crop triggers bottom-up cascades by favoring generalist over specialist herbivores

    Science.gov (United States)

    Graziosi, Ignazio; Burra, Dharani Dhar; Walter, Abigail Jan

    2017-01-01

    Global interest on plant-microbe-insect interactions is rapidly growing, revealing the multiple ways in which microorganisms mediate plant-herbivore interactions. Phytopathogens regularly alter whole repertoires of plant phenotypic traits, and bring about shifts in key chemical or morphological characteristics of plant hosts. Pathogens can also cause cascading effects on higher trophic levels, and eventually shape entire plant-associated arthropod communities. We tested the hypothesis that a Candidatus Phytoplasma causing cassava witches’ broom (CWB) on cassava (Manihot esculenta Grantz) is altering species composition of invasive herbivores and their associated parasitic hymenopterans. We conducted observational studies in cassava fields in eastern Cambodia to assess the effect of CWB infection on abundance of specialist and generalist mealybugs (Homoptera: Pseudococcidae), and associated primary and hyper-parasitoid species. CWB infection positively affects overall mealybug abundance and species richness at a plant- and field-level, and disproportionately favors a generalist mealybug over a specialist feeder. CWB phytoplasma infection led to increased parasitoid richness and diversity, with richness of ‘comparative’ specialist taxa being the most significantly affected. Parasitism rate did not differ among infected and uninfected plants, and mealybug host suppression was not impacted. CWB phytoplasma modifies host plant quality for sap-feeding homopterans, differentially affects success rates of two invasive species, and generates niche opportunities for higher trophic orders. By doing so, a Candidatus phytoplasma affects broader food web structure and functioning, and assumes the role of an ecosystem engineer. Our work unveils key facets of phytoplasma ecology, and sheds light upon complex multi-trophic interactions mediated by an emerging phytopathogen. These findings have further implications for invasion ecology and management. PMID:28813469

  11. Temporal Dynamics of Arthropods on Six Tree Species in Dry Woodlands on the Caribbean Island of Puerto Rico

    Science.gov (United States)

    Beltrán, William; Wunderle, Joseph M.

    2014-01-01

    Abstract The seasonal dynamics of foliage arthropod populations are poorly studied in tropical dry forests despite the importance of these studies for understanding arthropod population responses to environmental change. We monitored the abundance, temporal distributions, and body size of arthropods in five naturalized alien and one native tree species to characterize arthropod seasonality in dry novel Prosopis–Leucaena woodlands in Puerto Rico. A branch clipping method was used monthly to sample foliage arthropod abundance over 39 mo. Seasonal patterns of rainfall and abundance within various arthropod taxa were highly variable from year to year. Abundance for most taxa did not show significant seasonality over the 3 yr, although most taxa had abundance peaks each year. However, Homoptera displayed high seasonality with significant temporal aggregations in each year. Formicidae, Orthoptera, and Coleoptera showed high variation in abundance between wet and dry periods, whereas Hemiptera were consistently more abundant in the wet period. Seasonal differences in mean abundance were found only in a few taxa on Tamarindus indica L. , Bucida buceras L. , Pithecellobium dulce , and (Roxburgh) Benth. Mean arthropod abundance varied among tree species, with highest numbers on Prosopis juliflora , (Swartz) De Candolle, Pi. dulce , Leucaena leucocephala , and (Lamarck) de Wit. Abundance of Araneae, Orthoptera, Coleoptera, Lepidoptera larvae, and all arthropods showed weak relationships with one or more climatic variables (rainfall, maximum temperature, or relative humidity). Body size of arthropods was usually largest during the dry periods. Overall, total foliage arthropod abundance showed no consistent seasonality among years, which may become a more common trend in dry forests and woodlands in the Caribbean if seasonality of rainfall becomes less predictable. PMID:25502036

  12. Seleksi Resistansi Wereng Batang Padi Coklat terhadap Insektisida Fipronil

    Directory of Open Access Journals (Sweden)

    Melhanah Melhanah

    2002-12-01

    Full Text Available The rice brown planthoper, Nilaparvata lugens Stal (Homoptera: Delphacidae, is one of  key pests on rice. The use of insecticides unwisely has caused N. lugens to develop resistance. The objective of this research was to determine the potency of N. lugens to develop resistance through laboratory, selections to fipronil, a relatively new insecticide.  A population of N. lugens was collected from rice field in Muntilan, Central Java during the outbreak in 2001. Selections were carried out every generation for four generations against third instars. Selection was started by dipping Cisadane rice seedlings in a solution of fipronil (50 ppm. The concentration was increased every generation, and the concentration used for the last selection (the fourth generation was 250 ppm. To determine the rate of resistance development, biassays were carried out to estimate LC50 of fipronil against selected and non-selected populations of N. lugens, and their LC50 values were compared to that of the laboratory population. The laboratory population has been in the laboratory for 15 years without any insecticides exposure. The founding population was as susceptible as the laboratory population to fipronil because their LC50 values were similar. Even though the concentration for selections was increased from generation to generation, the survival rate of N. lugens increased steadily. After four generations of selection, the resistance of selected population was 27.3 times than the non-selected population. These findings indicate that N. lugens population has the potency to develop resistance to fipronil in a continuous selection pressure is applied.

  13. Seasonal shift from bottom-up to top-down impact in phytophagous insect populations.

    Science.gov (United States)

    Gratton, Claudio; Denno, Robert F

    2003-03-01

    Although many studies now examine how multiple factors influence the dynamics of herbivore populations, few studies explicitly attempt to document where and when each is important and how they vary and interact. In fact, how temporal variation in top-down (natural enemies) and bottom-up (host plant resources) factors affect herbivore dynamics has been suggested as a particularly important yet poorly understood feature of terrestrial food webs. In this study we examined how temporal changes in predator density (wolf spiders, sheet-web builders, and mirid egg predators) and host-plant resources (plant quality and structural complexity) influence the population dynamics of the dominant phytophagous insects on Atlantic-coast salt marshes, namely Prokelisia planthoppers (Homoptera: Delphacidae). We designed a factorial experiment in meadows of Spartina alterniflora to mimic natural variation in vegetation quality and structure by establishing two levels of plant nutrition (leaf nitrogen content) by fertilization, and two levels of habitat complexity by adding leaf litter (thatch). We then assessed seasonal changes in the strength of bottom-up (plant quality) and top-down (predator) impacts on planthopper populations. Planthopper populations responded positively to increased plant quality treatments in late summer. Despite the greater number of planthopper adults colonizing fertilized Spartina plots compared to unfertilized controls, the offspring of these colonists were much less abundant at the end of the season in fertilized plots, particularly those with thatch. The initial colonization effect was later erased because arthropod predators selectively accumulated in fertilized plots where they inflicted significant mortality on all stages of planthoppers. Predators rapidly colonized fertilized plots and reached high densities well in advance of planthopper colonization, a response we attribute to their rapid aggregation in complex-structured habitats with readily

  14. Genetic structure of the aphid, Chaetosiphon fragaefolii, and its role as a vector of the Strawberry Yellow Edge Virus to a native strawberry, Fragaria chiloensis in Chile.

    Science.gov (United States)

    Lavandero, Blas; Rojas, Pamela; Ramirez, Claudio C; Salazar, Marcela; Caligari, Peter D S

    2012-01-01

    The monoecious anholocyclical aphid, Chaetosiphon fragaefolii (Cockerell) (Homoptera: Aphididae), was collected on a native strawberry, Fragaria chiloensis (L.) Duchesne (Rosales: Rosaceae) from different sites in Chile. The presence of this aphid was recorded during two consecutive years. F. chiloensis plants were collected from seven natural and cultivated growing areas in central and southern Chile. Aphids were genotyped by cross-species amplification of four microsatellite loci from other aphid species. In addition, the aphid borne virus Strawberry mild yellow edge virus was confirmed in F. chiloensis plants by double-antibody sandwich ELISA and RT-PCR. Genetic variability and structure of the aphid populations was assessed from the geo-referenced individuals through AMOVA and a Bayesian assignment test. The presence of C. fragaefolii, during the two-year study was detected in only four of the seven sites (Curepto, Contulmo, Chilián and Cucao). Genetic variation among these populations reached 19% of the total variance. When assigning the individuals to groups, these were separated in three genetic clusters geographically disjunct. Of the seven sampled sites, six were positive for the virus by RT-PCR, and five by double-antibody sandwich ELISA . The incidence of the virus ranged from 0-100%. Presence of the virus corresponded with the presence of the aphid in all but two sites (Chilian and Vilches). The greatest incidence of Strawberry mild yellow edge virus was related to the abundance of aphids. On the other hand, sequences of the coat protein gene of the different virus samples did not show correspondence with either the genetic groups of the aphids or the sampling sites. The genetic structure of aphids could suggest that dispersal is mainly through human activities, and the spread to natural areas has not yet occurred on a great scale.

  15. Climate Risk Modelling of Balsam Woolly Adelgid Damage Severity in Subalpine Fir Stands of Western North America.

    Science.gov (United States)

    Hrinkevich, Kathryn H; Progar, Robert A; Shaw, David C

    2016-01-01

    The balsam woolly adelgid (Adelges piceae (Ratzeburg) (Homoptera: Adelgidae)) (BWA) is a nonnative, invasive insect that threatens Abies species throughout North America. It is well established in the Pacific Northwest, but continues to move eastward through Idaho and into Montana and potentially threatens subalpine fir to the south in the central and southern Rocky Mountains. We developed a climatic risk model and map that predicts BWA impacts to subalpine fir using a two-step process. Using 30-year monthly climate normals from sites with quantitatively derived BWA damage severity index values, we built a regression model that significantly explained insect damage. The sites were grouped into two distinct damage categories (high damage and mortality versus little or no mortality and low damage) and the model estimates for each group were used to designate distinct value ranges for four climatic risk categories: minimal, low, moderate, and high. We then calculated model estimates for each cell of a 4-kilometer resolution climate raster and mapped the risk categories over the entire range of subalpine fir in the western United States. The spatial variation of risk classes indicates a gradient of climatic susceptibility generally decreasing from the Olympic Peninsula in Washington and the Cascade Range in Oregon and Washington moving eastward, with the exception of some high risk areas in northern Idaho and western Montana. There is also a pattern of decreasing climatic susceptibility from north to south in the Rocky Mountains. Our study provides an initial step for modeling the relationship between climate and BWA damage severity across the range of subalpine fir. We showed that September minimum temperature and a metric calculated as the maximum May temperature divided by total May precipitation were the best climatic predictors of BWA severity. Although winter cold temperatures and summer heat have been shown to influence BWA impacts in other locations, these

  16. The significance of facultative scavenging in generalist predator nutrition: detecting decayed prey in the guts of predators using PCR.

    Science.gov (United States)

    Foltan, Pavel; Sheppard, Samuel; Konvicka, Martin; Symondson, William O C

    2005-11-01

    Gut-content analyses using molecular techniques are an effective approach to quantifying predator-prey interactions. Predation is often assumed but scavenging is an equally likely route by which animal DNA enters the gut of a predator/scavenger. We used PCR (polymerase chain reaction) to detect scavenged material in predator gut homogenates. The rates at which DNA in decaying slugs (Mollusca: Pulmonata) and aphids (Homoptera: Aphididae) became undetectable were estimated. The detectability of DNA from both carrion types in the guts of the generalist predator Pterostichus melanarius (Coleoptera: Carabidae) was then determined. The effects of carrion age and weight, as well as beetle sex, on detection periods, were quantified. Laboratory trials measured prey preference of beetles between live and decaying prey. Further experiments measured, for the first time, feeding by P. melanarius on dead slugs and aphids directly in the field. In both field and laboratory, P. melanarius preferentially fed on dead prey if available, but preference changed as the prey became increasingly decayed. Disappearance rates for slug carrion in wheat fields and grasslands were estimated and P. melanarius was identified as the main scavenger. Comparison of the retention time for dead slugs in the field, with the detection period for decaying slug material in the guts of the predators, showed that PCR-based techniques are not able to distinguish between predated and scavenged food items. This could potentially lead to overestimation of the impact of predation on slugs (and other prey) by carabids. Possible implications of facultative scavenging by invertebrate predators for biocontrol and food-web research are discussed.

  17. The entomopathogenic fungal endophytes Purpureocillium lilacinum (formerly Paecilomyces lilacinus and Beauveria bassiana negatively affect cotton aphid reproduction under both greenhouse and field conditions.

    Directory of Open Access Journals (Sweden)

    Diana Castillo Lopez

    Full Text Available The effects of two entomopathogenic fungal endophytes, Beauveria bassiana and Purpureocillium lilacinum (formerly Paecilomyces lilacinus, were assessed on the reproduction of cotton aphid, Aphis gossypii Glover (Homoptera:Aphididae, through in planta feeding trials. In replicate greenhouse and field trials, cotton plants (Gossypium hirsutum were inoculated as seed treatments with two concentrations of B. bassiana or P. lilacinum conidia. Positive colonization of cotton by the endophytes was confirmed through potato dextrose agar (PDA media plating and PCR analysis. Inoculation and colonization of cotton by either B. bassiana or P. lilacinum negatively affected aphid reproduction over periods of seven and 14 days in a series of greenhouse trials. Field trials were conducted in the summers of 2012 and 2013 in which cotton plants inoculated as seed treatments with B. bassiana and P. lilacinum were exposed to cotton aphids for 14 days. There was a significant overall effect of endophyte treatment on the number of cotton aphids per plant. Plants inoculated with B. bassiana had significantly lower numbers of aphids across both years. The number of aphids on plants inoculated with P. lilacinum exhibited a similar, but non-significant, reduction in numbers relative to control plants. We also tested the pathogenicity of both P. lilacinum and B. bassiana strains used in the experiments against cotton aphids in a survival experiment where 60% and 57% of treated aphids, respectively, died from infection over seven days versus 10% mortality among control insects. Our results demonstrate (i the successful establishment of P. lilacinum and B. bassiana as endophytes in cotton via seed inoculation, (ii subsequent negative effects of the presence of both target endophytes on cotton aphid reproduction using whole plant assays, and (iii that the P. lilacinum strain used is both endophytic and pathogenic to cotton aphids. Our results illustrate the potential of

  18. Identification of semiochemicals released by cotton, Gossypium hirsutum, upon infestation by the cotton aphid, Aphis gossypii.

    Science.gov (United States)

    Hegde, Mahabaleshwar; Oliveira, Janser N; da Costa, Joao G; Bleicher, Ervino; Santana, Antonio E G; Bruce, Toby J A; Caulfield, John; Dewhirst, Sarah Y; Woodcock, Christine M; Pickett, John A; Birkett, Michael A

    2011-07-01

    The cotton aphid, Aphis gossypii (Homoptera: Aphididae), is increasing in importance as a pest worldwide since the introduction of Bt-cotton, which controls lepidopteran but not homopteran pests. The chemical ecology of interactions between cotton, Gossypium hirsutum (Malvaceae), A. gossypii, and the predatory lacewing Chrysoperla lucasina (Neuroptera: Chrysopidae), was investigated with a view to providing new pest management strategies. Behavioral tests using a four-arm (Pettersson) olfactometer showed that alate A. gossypii spent significantly more time in the presence of odor from uninfested cotton seedlings compared to clean air, but significantly less time in the presence of odor from A. gossypii infested plants. A. gossypii also spent significantly more time in the presence of headspace samples of volatile organic compounds (VOCs) obtained from uninfested cotton seedlings, but significantly less time with those from A. gossypii infested plants. VOCs from uninfested and A. gossypii infested cotton seedlings were analyzed by gas chromatography (GC) and coupled GC-mass spectrometry (GC-MS), leading to the identification of (Z)-3-hexenyl acetate, (E)-4,8-dimethyl-1,3,7-nonatriene (DMNT), methyl salicylate, and (E,E)-4,8,12-trimethyl-1,3,7,11-tridecatetraene (TMTT), which were produced in larger amounts from A. gossypii infested plants compared to uninfested plants. In behavioral tests, A. gossypii spent significantly more time in the control (solvent) arms when presented with a synthetic blend of these four compounds, with and without the presence of VOCs from uninfested cotton. Coupled GC-electroantennogram (EAG) recordings with the lacewing C. lucasina showed significant antennal responses to VOCs from A. gossypii infested cotton, suggesting they have a role in indirect defense and indicating a likely behavioral role for these compounds for the predator as well as the aphid.

  19. Macrofauna edáfica asociada con sistemas agroforestales en la Amazonía Colombiana

    Directory of Open Access Journals (Sweden)

    Juan Carlos Suárez Salazar

    2015-07-01

    Full Text Available La densidad, riqueza y diversidad de la macrofauna edáfica son afectadas, entre otros factores, por la configuración de los agroecosistemas y la estacionalidad de la precipitación. Con el fin de evaluar estos efectos en mayo y noviembre de 2011, correspondientes a épocas de máxima y mínima precipitación, respectivamente, se realizaron estudios sobre la composición de la macrofauna edáfica asociada con los arreglos agroforestales ubicados en el Centro de Investigaciones Macagual Cesar Augusto Estrada González, Amazonia, Caquetá, Colombia. El experimento se dispuso en un diseño completo al azar bifactorial con cuatro tratamientos (arreglos agroforestales: AB = abarco - Cariniana pyriformis Miers; CH = caucho Hevea brasiliensis (Willd. ex A. Juss. Müll. Arg. ; CP = caucho-parica Schizolobium amazonicum Huber; UV = uvito Genipa Americana L. y dos épocas (máxima y mínima precipitación, y cuatro repeticiones en parcelas divididas. Para explorar las relaciones entre los órdenes de macrofauna, se realizó un análisis de componentes principales y se evalúo el efecto de los arreglos agroforestales con una prueba de Monte Carlo. Los resultados mostraron que la densidad de la macrofauna fue mayor en el periodo de máxima precipitación (1129 individuos en comparación con el de mínima (598 individuos. Los arreglos agroforestales influyen sobre la presencia o ausencia de algunos grupos taxonómicos (P < 0.05 como Homoptera (Insecta y Raphidioptera (Insecta; además los UV y AB pueden favorecer a la macrofauna del estrés por sequía

  20. Insect emergence in relation to floods in wet meadows and swamps in the River Dalälven floodplain.

    Science.gov (United States)

    Vinnersten, T Z Persson; Östman, Ö; Schäfer, M L; Lundström, J O

    2014-08-01

    Annual variation in flood frequency and hydroperiod during the vegetation season has ecological impacts on the floodplain biota. Although many insect groups may have a lower emergence during a flood event, it is poorly known how annual emergence of insects in temporary wetlands is related to the variation in hydrology. Between May and September, we studied the weekly emergence of 18 insect taxa over six consecutive years, 2002-2007, in six temporary flooded wetlands (four wet meadows and two forest swamps) in the River Dalälven floodplains, Central Sweden. We used emergence traps to collect emerging insects from terrestrial and aquatic parts of wet meadows and swamp forests. In all wetlands, the insect fauna was numerically dominated by the orders Diptera, Hymenoptera, Coleoptera and Homoptera. On a weekly basis, 9 out of the 18 insect taxa had lower emergence in weeks with flood than in weeks with no flood, whereas no taxon had a higher emergence in weeks with flood. Over the seasons, we related insect emergence to seasonal flood frequency and length of hydroperiod. The emergence of most studied taxa decreased with increasing hydroperiod, which suggests that emergence after floods do not compensate for the reduced emergence during floods. Only Culicidae and the aquatic Chironomidae sub-families Tanypodinae and Chironominae showed an increase in emergence with increasing hydroperiod, whereas Staphylinidae peaked at intermediate hydroperiod. We conclude that a hydroperiod covering up to 40% of the vegetation season has a significant negative effect on the emergence of most taxa and that only a few taxa occurring in the temporary wetlands are actually favoured by a flood regime with recurrent and unpredictable floods.

  1. Relationship of coarse woody debris to arthropod Availability for Red-Cockaded Woodpeckers and other bark-foraging birds on loblolly pine boles.

    Energy Technology Data Exchange (ETDEWEB)

    Horn, Scott; Hanula, James, L.

    2008-04-01

    Abstract This study determined if short-term removal of coarse woody debris would reduce prey available to red-cockaded woodpeckers (Picoides borealis Vieillot) and other bark-foraging birds at the Savannah River Site in Aiken and Barnwell counties, SC. All coarse woody debris was removed from four 9-ha plots of mature loblolly pine (Pinus taeda L.) in 1997 and again in 1998. We sampled arthropods in coarse woody debris removal and control stands using crawl traps that captured arthropods crawling up tree boles, burlap bands wrapped around trees, and cardboard panels placed on the ground. We captured 27 orders and 172 families of arthropods in crawl traps whereas 20 arthropod orders were observed under burlap bands and cardboard panels. The most abundant insects collected from crawl traps were aphids (Homoptera: Aphididae) and ants (Hymenoptera: Forrnicidae). The greatest biomass was in the wood cockroaches (Blattaria: Blattellidae), caterpillars (Lepidoptera) in the Family Noctuidae, and adult weevils (Coleoptera: Curculionidae). The most common group observed underneath cardboard panels was lsoptera (termites), and the most common taxon under burlap bands was wood cockroaches. Overall, arthropod abundance and biomass captured in crawl traps was similar in control and removal plots. In contrast, we observed more arthropods under burlap bands (mean & SE; 3,021.5 k 348.6, P= 0.03) and cardboard panels (3,537.25 k 432.4, P= 0.04) in plots with coarse woody debris compared with burlap bands (2325 + 171.3) and cardboard panels (2439.75 + 288.9) in plots where coarse woody debris was removed. Regression analyses showed that abundance beneath cardboard panels was positively correlated with abundance beneath burlap bands demonstrating the link between abundance on the ground with that on trees. Our results demonstrate that short-term removal of coarse woody debris from pine forests reduced overall arthropod availability to bark-foraging birds.

  2. The entomopathogenic fungal endophytes Purpureocillium lilacinum (formerly Paecilomyces lilacinus) and Beauveria bassiana negatively affect cotton aphid reproduction under both greenhouse and field conditions.

    Science.gov (United States)

    Castillo Lopez, Diana; Zhu-Salzman, Keyan; Ek-Ramos, Maria Julissa; Sword, Gregory A

    2014-01-01

    The effects of two entomopathogenic fungal endophytes, Beauveria bassiana and Purpureocillium lilacinum (formerly Paecilomyces lilacinus), were assessed on the reproduction of cotton aphid, Aphis gossypii Glover (Homoptera:Aphididae), through in planta feeding trials. In replicate greenhouse and field trials, cotton plants (Gossypium hirsutum) were inoculated as seed treatments with two concentrations of B. bassiana or P. lilacinum conidia. Positive colonization of cotton by the endophytes was confirmed through potato dextrose agar (PDA) media plating and PCR analysis. Inoculation and colonization of cotton by either B. bassiana or P. lilacinum negatively affected aphid reproduction over periods of seven and 14 days in a series of greenhouse trials. Field trials were conducted in the summers of 2012 and 2013 in which cotton plants inoculated as seed treatments with B. bassiana and P. lilacinum were exposed to cotton aphids for 14 days. There was a significant overall effect of endophyte treatment on the number of cotton aphids per plant. Plants inoculated with B. bassiana had significantly lower numbers of aphids across both years. The number of aphids on plants inoculated with P. lilacinum exhibited a similar, but non-significant, reduction in numbers relative to control plants. We also tested the pathogenicity of both P. lilacinum and B. bassiana strains used in the experiments against cotton aphids in a survival experiment where 60% and 57% of treated aphids, respectively, died from infection over seven days versus 10% mortality among control insects. Our results demonstrate (i) the successful establishment of P. lilacinum and B. bassiana as endophytes in cotton via seed inoculation, (ii) subsequent negative effects of the presence of both target endophytes on cotton aphid reproduction using whole plant assays, and (iii) that the P. lilacinum strain used is both endophytic and pathogenic to cotton aphids. Our results illustrate the potential of using these

  3. Comparative Proteomic Analysis of Susceptible and Resistant Rice Plants during Early Infestation by Small Brown Planthopper.

    Science.gov (United States)

    Dong, Yan; Fang, Xianping; Yang, Yong; Xue, Gang-Ping; Chen, Xian; Zhang, Weilin; Wang, Xuming; Yu, Chulang; Zhou, Jie; Mei, Qiong; Fang, Wang; Yan, Chengqi; Chen, Jianping

    2017-01-01

    The small brown planthopper (Laodelphax striatellus Fallén, Homoptera, Delphacidae-SBPH) is one of the major destructive pests of rice (Oryza sativa L.). Understanding on how rice responds to SBPH infestation will contribute to developing strategies for SBPH control. However, the response of rice plant to SBPH is poorly understood. In this study, two contrasting rice genotypes, Pf9279-4 (SBPH-resistant) and 02428 (SBPH-susceptible), were used for comparative analysis of protein profiles in the leaf sheath of rice plants in responses to SBPH infestation. One hundred and thirty-two protein spots that were differentially expressed between the resistant and susceptible rice lines were identified with significant intensity differences (≥2-fold, P < 0.05) at 0, 6, and 12 h after SBPH infestation. Protein expression profile analysis in the leaf sheath of SBPH-resistant and SBPH-susceptible rice lines after SBPH infestation showed that proteins induced by SBPH feeding were involved mainly in stress response, photosynthesis, protein metabolic process, carbohydrate metabolic process, energy metabolism, cell wall-related proteins, amino acid metabolism and transcriptional regulation. Gene expression analysis of 24 differentially expressed proteins (DEPs) showed that more than 50% DEPs were positively correlated with their mRNA levels. Analysis of some physiological indexes mainly involved in the removal of oxygen reactive species showed that the levels of superoxide dismutase (SOD) and glutathione (GSH) were considerably higher in Pf9279-4 than 02428 during SBPH infestation. The catalase (CAT) activity and hydroxyl radical inhibition were lower in Pf9279-4 than 02428. Analysis of enzyme activities indicates that Pf9279-4 rice plants defend against SBPH through the activation of the pathway of the salicylic acid (SA)-dependent systemic acquired resistance. In conclusion, this study provides some insights into the molecular networks involved on cellular and physiological

  4. Comparative Proteomic Analysis of Susceptible and Resistant Rice Plants during Early Infestation by Small Brown Planthopper

    Directory of Open Access Journals (Sweden)

    Yan Dong

    2017-10-01

    Full Text Available The small brown planthopper (Laodelphax striatellus Fallén, Homoptera, Delphacidae-SBPH is one of the major destructive pests of rice (Oryza sativa L.. Understanding on how rice responds to SBPH infestation will contribute to developing strategies for SBPH control. However, the response of rice plant to SBPH is poorly understood. In this study, two contrasting rice genotypes, Pf9279-4 (SBPH-resistant and 02428 (SBPH-susceptible, were used for comparative analysis of protein profiles in the leaf sheath of rice plants in responses to SBPH infestation. One hundred and thirty-two protein spots that were differentially expressed between the resistant and susceptible rice lines were identified with significant intensity differences (≥2-fold, P < 0.05 at 0, 6, and 12 h after SBPH infestation. Protein expression profile analysis in the leaf sheath of SBPH-resistant and SBPH-susceptible rice lines after SBPH infestation showed that proteins induced by SBPH feeding were involved mainly in stress response, photosynthesis, protein metabolic process, carbohydrate metabolic process, energy metabolism, cell wall-related proteins, amino acid metabolism and transcriptional regulation. Gene expression analysis of 24 differentially expressed proteins (DEPs showed that more than 50% DEPs were positively correlated with their mRNA levels. Analysis of some physiological indexes mainly involved in the removal of oxygen reactive species showed that the levels of superoxide dismutase (SOD and glutathione (GSH were considerably higher in Pf9279-4 than 02428 during SBPH infestation. The catalase (CAT activity and hydroxyl radical inhibition were lower in Pf9279-4 than 02428. Analysis of enzyme activities indicates that Pf9279-4 rice plants defend against SBPH through the activation of the pathway of the salicylic acid (SA-dependent systemic acquired resistance. In conclusion, this study provides some insights into the molecular networks involved on cellular and

  5. Climate Risk Modelling of Balsam Woolly Adelgid Damage Severity in Subalpine Fir Stands of Western North America.

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    Kathryn H Hrinkevich

    Full Text Available The balsam woolly adelgid (Adelges piceae (Ratzeburg (Homoptera: Adelgidae (BWA is a nonnative, invasive insect that threatens Abies species throughout North America. It is well established in the Pacific Northwest, but continues to move eastward through Idaho and into Montana and potentially threatens subalpine fir to the south in the central and southern Rocky Mountains. We developed a climatic risk model and map that predicts BWA impacts to subalpine fir using a two-step process. Using 30-year monthly climate normals from sites with quantitatively derived BWA damage severity index values, we built a regression model that significantly explained insect damage. The sites were grouped into two distinct damage categories (high damage and mortality versus little or no mortality and low damage and the model estimates for each group were used to designate distinct value ranges for four climatic risk categories: minimal, low, moderate, and high. We then calculated model estimates for each cell of a 4-kilometer resolution climate raster and mapped the risk categories over the entire range of subalpine fir in the western United States. The spatial variation of risk classes indicates a gradient of climatic susceptibility generally decreasing from the Olympic Peninsula in Washington and the Cascade Range in Oregon and Washington moving eastward, with the exception of some high risk areas in northern Idaho and western Montana. There is also a pattern of decreasing climatic susceptibility from north to south in the Rocky Mountains. Our study provides an initial step for modeling the relationship between climate and BWA damage severity across the range of subalpine fir. We showed that September minimum temperature and a metric calculated as the maximum May temperature divided by total May precipitation were the best climatic predictors of BWA severity. Although winter cold temperatures and summer heat have been shown to influence BWA impacts in other

  6. Acetic acid bacteria, newly emerging symbionts of insects.

    Science.gov (United States)

    Crotti, Elena; Rizzi, Aurora; Chouaia, Bessem; Ricci, Irene; Favia, Guido; Alma, Alberto; Sacchi, Luciano; Bourtzis, Kostas; Mandrioli, Mauro; Cherif, Ameur; Bandi, Claudio; Daffonchio, Daniele

    2010-11-01

    Recent research in microbe-insect symbiosis has shown that acetic acid bacteria (AAB) establish symbiotic relationships with several insects of the orders Diptera, Hymenoptera, Hemiptera, and Homoptera, all relying on sugar-based diets, such as nectars, fruit sugars, or phloem sap. To date, the fruit flies Drosophila melanogaster and Bactrocera oleae, mosquitoes of the genera Anopheles and Aedes, the honey bee Apis mellifera, the leafhopper Scaphoideus titanus, and the mealybug Saccharicoccus sacchari have been found to be associated with the bacterial genera Acetobacter, Gluconacetobacter, Gluconobacter, Asaia, and Saccharibacter and the novel genus Commensalibacter. AAB establish symbiotic associations with the insect midgut, a niche characterized by the availability of diet-derived carbohydrates and oxygen and by an acidic pH, selective factors that support AAB growth. AAB have been shown to actively colonize different insect tissues and organs, such as the epithelia of male and female reproductive organs, the Malpighian tubules, and the salivary glands. This complex topology of the symbiosis indicates that AAB possess the keys for passing through body barriers, allowing them to migrate to different organs of the host. Recently, AAB involvement in the regulation of innate immune system homeostasis of Drosophila has been shown, indicating a functional role in host survival. All of these lines of evidence indicate that AAB can play different roles in insect biology, not being restricted to the feeding habit of the host. The close association of AAB and their insect hosts has been confirmed by the demonstration of multiple modes of transmission between individuals and to their progeny that include vertical and horizontal transmission routes, comprising a venereal one. Taken together, the data indicate that AAB represent novel secondary symbionts of insects.

  7. Studying genetic diversity of whitefly B. tabaci Egyptian isolates in relation to some worldwide isolates

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    Inas Farouk Fahmy

    2015-06-01

    Full Text Available Bemisia tabaci (Gennadius (Hemiptera, Aleyrodidae is considered to be one of the most damaging pests in agriculture, causing severe losses in crops worldwide, affecting the tropical and subtropical regions. Random Amplified Polymorphic DNA-Polymerase Chain Reaction (RAPD-PCR was used to assess the genetic diversity between different isolates collected from different regions in Egypt compared with some other worldwide isolates of this insect pest. Out of 12 primers 8 primers from Operon technology have shown to differentiate between 13 collected B. tabaci samples from all over Egypt and some other samples collected from different countries with two other populations representing biotypes A and B collected from the US used for biotype demarcation. Using 13 insect samples, RAPD analysis has produced a total number of 72 markers; about 68 polymorphic markers were revealed. The total number of bands obtained for each primer ranged from 4 to 14 within an average of 9 bands per primer. Of the pair wise combination among fifteen populations Ismailia population showed the highest similarity index (0.947, while US biotype A scored the lowest similarity index (0.326. Two major clusters were formed from the UPGMA dendrogram, which was constructed based on Dice similarity coefficient. RAPD-PCR screening demarcated the whitefly population based on the host species and genetic biotypes. Two major clusters have been revealed as A and B with two other minor clusters A1, A2, and B1, B2. Most of the samples collected from Egypt were clustered together in a minor cluster named A1. A1 group is divided into two sub-groups. A1a comprises the populations from Beni-Sweif in Upper Egypt, Ismailia, Kalyobia, El-Fayoum, Tanta, Kafr El-Sheikh, Alexandria, and A1b comprises Spain and Sudan. Group A1a is clustered together based on their host which belongs to the Cucurbitaceae family while Alexandria was separated individually based on its host which is cauliflower. Through

  8. Genetic diversity of Bemisia tabaci species colonizing cassava in Central African Republic characterized by analysis of cytochrome c oxidase subunit I.

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    Brice Kette Tocko-Marabena

    Full Text Available After 2007, upsurges of whiteflies on cassava plants and high incidences of cassava diseases were observed in Central African Republic. This recent upsurge in the abundance of Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae was directly linked to serious damage to cassava crops resulting from spread of whitefly-borne cassava mosaic geminiviruses (CMGs. There is currently very little information describing whitefly populations on cassava and associated crops in Central African Republic. The current study aimed to address this gap, and to determine whether the increasing damage associated with B. tabaci whiteflies was the consequence of a new invasion, or an upsurge of a local population. The molecular genetic identification and phylogenetic relationships of 898 B. tabaci adult individuals collected from representative locations (54 throughout CAR were determined based on their mitochondrial cytochrome oxidase I sequences (mtCOI. Field and ecological data were also collected from each site, including whitefly abundance, CMD incidence, host plants colonized by B. tabaci and agro-ecological zone. Phylogenetic analysis of the whitefly mtCOI sequences indicated that SSA1 (-SG1, -SG2, SSA3, MED, MEAM1 and Indian Ocean (IO putative species occur in CAR. One specific haplotype of SSA1-SG1 (SSA1-SG1-P18F5 predominated on most cassava plants and at the majority of sites. This haplotype was identical to the SSA1-SG1 Mukono8-4 (KM377961 haplotype that was recorded from Uganda but that also occurs widely in CMD pandemic-affected areas of East Africa. These results suggest that the SSA1-SG1-P18F5 haplotype occurring in CAR represents a recent invasive population, and that it is the likely cause of the increased spread and severity of CMD in CAR. Furthermore, the high mtDNA sequence diversity observed for SSA1 and its broad presence on all sites and host plants sampled suggest that this genetic group was the dominant resident species even before the arrival

  9. Insecticidal Activity of Some Reducing Sugars Against the Sweet Potato Whitefly, Bemisia tabaci, Biotype B

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    Hu, Jing S.; Gelman, Dale B.; Salvucci, Michael E.; Chen, Yan P.; Blackburn, Michael B.

    2010-01-01

    The effects of 16 sugars (arabinose, cellobiose, fructose, galactose, gentiobiose, glucose, inositol, lactose, maltose, mannitol (a sugar alcohol), mannose, melibiose, ribose, sorbitol, trehalose, and xylose) on sweet potato whitefly Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) survival were determined using in vitro bioassays. Of these sugars, arabinose, mannose, ribose, and xylose were strongly inhibitory to both nymphal and adult survival. When 10% mannose was added to the nymphal diet, 10.5%, 1.0%, and 0% developed to the 2nd, 3rd, and 4th instars, respectively. When 10% arabinose was added, 10.8% and 0% of the nymphs molted to the 2nd and 3rd instars, respectively. Addition of 10% xylose or ribose completely terminated B. tabaci development, preventing the molt to the 2nd instar. With decreasing sugar concentrations the inhibitory effect was significantly reduced. In tests using adults, arabinose, galactose, inositol, lactose, maltose, mannitol, mannose, melibiose, ribose, sorbitol, trehalose, and xylose significantly reduced mean day survival. Mortality rates were highest when arabinose, mannitol, mannose, ribose, or xylose was added to the diet. Mean day survival was less than 2 days when adults were fed on diet containing 10% of any one of these five sugars. When lower concentrations of sugars were used there was a decrease in mortality. Mode of action studies revealed that toxicity was not due to the inhibition of alpha glucosidase (converts sucrose to glucose and fructose) and/or trehalulose synthase (converts sucrose to trehalulose) activity. The result of agarose gel electrophoresis of RT-PCR products of bacterial endosymbionts amplified from RNA isolated from whiteflies fed with 10% arabinose, mannose, or xylose indicated that the concentration of endosymbionts in mycetomes was not affected by the toxic sugars. Experiments in which B. tabaci were fed on diets that contained radio-labeled sucrose, methionine or inulin and one or none (control) of

  10. Antalya İlinde Portakal Bahçelerinde Gözlenen Önemli Zararlı ve Yararlı Böcek Popülasyonları

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    Vildan GÖL

    2016-06-01

    Full Text Available Bu çalışmada, 2014 yılında, Antalya ilinde bulunan iki portakal bahçesinde önemli zararlı ve yararlı böcek popülasyonları belirlenmiştir. Bahçelerde ağırlıklı olarak portakal bulunması nedeniyle örneklemeler de bu tür üzerinde yapılmıştır. Çalışma süresince zararlılara karşı herhangi bir mücadele yöntemi uygulanmamıştır. Çalışmada örneklerin toplanması için gözle kontrol yöntemi, yaprak, sürgün, meyve örnekleme yöntemi, darbe ve tuzakla yakalama yöntemi kullanılmıştır. Çalışma sonucunda zararlı türler olarak Tetranychus urticae (Koch (Acarina: Tetranychidae, Empoasca decipiens (Paoli, Asymmetrasca decedens (Paoli (Hemiptera: Cicadellidae, Dialeurodes citri (Ashmead, Aleurothrixus floccosus (Maskell (Hem.: Aleyrodidae, Aphis craccivora (Koch (Hem.: Aphididae, Icerya purchasi Maskell (Hem.: Margarodidae, Coccus hesperidum (Linnaeus, Ceroplastes floridensis (Comstock (Hem.: Coccidae, Aonidiella aurantii (Maskell, Aonidiella citrina (Coquillet, Parlatoria pergandii (Comstock (Hem.: Diaspididae, Planococcus citri (Risso (Hem.: Pseudococcidae, Ceratitis capitata (Wiedemann (Diptera: Tephritidae ve Phyllocnistis citrella (Stainton (Lepidoptera: Gracillaridae saptanmıştır. Bunlardan E. decipiens (Paoli, A. decedens (Paoli, A. floccosus (Maskell, A. aurantii (Maskell ve Parlatoria pergandii (Comstock en yaygın türler olarak belirlenmiştir. Ayrıca 2 takıma bağlı 7 avcı ve asalak tür saptanmıştır. Bu türler: Chrysoperla carnea (Stephens (Neuroptera: Chrysopidae, Coccinella septempunctata L., Chilocorus bipustulatus L., Rhyzobius lophantae (Blaisdell, Oenopia conglobata (L. (Coleoptera: Coccinellidae, Aphytis melinus DeBach ve Comperiella bifasciata (Coleoptera: Aphelinidae’ dır. Çalışmada ayrıca zararlı iki cicadellid türü ile A. floccosus, A. aurantii, P. pergandii, C. capitata‘nın ve doğal düşmanlardan C. carnea’nın, coccinellidlerin, A. melinus ve E. citrina

  11. Contribución al conocimiento de las interacciones entre plantas, hormigas y homópteros en bosques secos de Colombia

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    Ramírez Mónica

    2001-12-01

    Full Text Available Las interacciones entre plantas y hormigas y entre plantas, hormigas y homópteros se estudiaron en 248 estaciones de muestreo situadas en nueve fragmentos de bosque seco del valle geográfico del río Cauca, entre enero y junio de 1997. Se registraron 352 interacciones que involucran 91 especies vegetales, hormigas de 67 especies y homópteros pertenecientes a nueve familias. El 4 7% de las asociaciones registradas implica el uso por parte de las hormigas de diferentes estructuras de las plantas (p. e. raíces de las epífitas, domacios en los tallos, hojarasca acumulada entre ramas y hojas, brácteas y peciolos de Heliconia spp. como refugios temporales o sitios de anidamiento. El restante 53% involucra la recolección de miel de homópteros y de sustancias azucaradas en nectarios extraflorales. asmannia auropunctata (17%, Dolichoderus bispinosus (11% Y Brachymyrmex heeri (7% fueron las especies de hormigas registradas con mayor frecuencia. Las plantas más utilizadas fueron Heliconia stricta (8%, Philodendron sp. nov. (7% y Passiflora coriacea (5%. Entre las relaciones observadas, predominan las de tipo generalista, en que las hormigas explotan diferentes recursos aparentemente en forma oportunista y las plantas pueden encontrarse en buen estado a pesar de la ausencia de las hormigas.Interactions between ants and plants and those involving homopterans were studied in 248 sampling points located within nine tropical decidous forest fragments in the Cauca river Valley, between january and june, 1997. A total of 352 interactions were recorded involving 91 plant species, 67 ant species and Homoptera belonging to nine families. 47% ofthe interactions involved ants using different plant structures (such as epiphyte roots, domacia, litter collected in branches and leaves, bracts and petioles of Heliconia spp. as nesting sites or temporary refugia. The remaining 53% involved the collection of homopteran honeydew and sugary substances from extrafloral

  12. What is the phylogenetic signal limit from mitogenomes? The reconciliation between mitochondrial and nuclear data in the Insecta class phylogeny

    Science.gov (United States)

    2011-01-01

    Background Efforts to solve higher-level evolutionary relationships within the class Insecta by using mitochondrial genomic data are hindered due to fast sequence evolution of several groups, most notably Hymenoptera, Strepsiptera, Phthiraptera, Hemiptera and Thysanoptera. Accelerated rates of substitution on their sequences have been shown to have negative consequences in phylogenetic inference. In this study, we tested several methodological approaches to recover phylogenetic signal from whole mitochondrial genomes. As a model, we used two classical problems in insect phylogenetics: The relationships within Paraneoptera and within Holometabola. Moreover, we assessed the mitochondrial phylogenetic signal limits in the deeper Eumetabola dataset, and we studied the contribution of individual genes. Results Long-branch attraction (LBA) artefacts were detected in all the datasets. Methods using Bayesian inference outperformed maximum likelihood approaches, and LBA was avoided in Paraneoptera and Holometabola when using protein sequences and the site-heterogeneous mixture model CAT. The better performance of this method was evidenced by resulting topologies matching generally accepted hypotheses based on nuclear and/or morphological data, and was confirmed by cross-validation and simulation analyses. Using the CAT model, the order Strepsiptera was recovered as sister to Coleoptera for the first time using mitochondrial sequences, in agreement with recent results based on large nuclear and morphological datasets. Also the Hymenoptera-Mecopterida association was obtained, leaving Coleoptera and Strepsiptera as the basal groups of the holometabolan insects, which coincides with one of the two main competing hypotheses. For the Paraneroptera, the currently accepted non-monophyly of Homoptera was documented as a phylogenetic novelty for mitochondrial data. However, results were not satisfactory when exploring the entire Eumetabola, revealing the limits of the phylogenetic

  13. What is the phylogenetic signal limit from mitogenomes? The reconciliation between mitochondrial and nuclear data in the Insecta class phylogeny

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    Talavera Gerard

    2011-10-01

    Full Text Available Abstract Background Efforts to solve higher-level evolutionary relationships within the class Insecta by using mitochondrial genomic data are hindered due to fast sequence evolution of several groups, most notably Hymenoptera, Strepsiptera, Phthiraptera, Hemiptera and Thysanoptera. Accelerated rates of substitution on their sequences have been shown to have negative consequences in phylogenetic inference. In this study, we tested several methodological approaches to recover phylogenetic signal from whole mitochondrial genomes. As a model, we used two classical problems in insect phylogenetics: The relationships within Paraneoptera and within Holometabola. Moreover, we assessed the mitochondrial phylogenetic signal limits in the deeper Eumetabola dataset, and we studied the contribution of individual genes. Results Long-branch attraction (LBA artefacts were detected in all the datasets. Methods using Bayesian inference outperformed maximum likelihood approaches, and LBA was avoided in Paraneoptera and Holometabola when using protein sequences and the site-heterogeneous mixture model CAT. The better performance of this method was evidenced by resulting topologies matching generally accepted hypotheses based on nuclear and/or morphological data, and was confirmed by cross-validation and simulation analyses. Using the CAT model, the order Strepsiptera was recovered as sister to Coleoptera for the first time using mitochondrial sequences, in agreement with recent results based on large nuclear and morphological datasets. Also the Hymenoptera-Mecopterida association was obtained, leaving Coleoptera and Strepsiptera as the basal groups of the holometabolan insects, which coincides with one of the two main competing hypotheses. For the Paraneroptera, the currently accepted non-monophyly of Homoptera was documented as a phylogenetic novelty for mitochondrial data. However, results were not satisfactory when exploring the entire Eumetabola, revealing the

  14. Whole-tree sap flow is substantially diminished by leaf herbivory.

    Science.gov (United States)

    Cunningham, Saul A; Pullen, Kimberi R; Colloff, Matthew J

    2009-01-01

    Ecohydrological models consider the relationship between tree size and structure (especially leaf area index) and water use but generally treat herbivory as a source of unwanted noise in the data. Little is known of how insect damage to leaves influences whole-plant water use in trees. Water use is driven by environmental demand and the total leaf area through which transpiration can occur, but the effects of insects are expected to be complex. Different kinds of insects could have different effects; for example, chewing insects reduce leaf area, whereas sucking and tissue mining insects reduce leaf function without reducing area. Further, plants respond to herbivory in a range of ways, such as by altering leaf production or abscising leaves. We examined the effect of insects on Eucalyptus blakelyi in a woodland near Canberra, Australia, using sap flow velocity as a measure of whole-plant water use. We applied insecticide to 16 trees matched to an untreated control group. After 6 months, we examined the effects on sap flow velocity and crown condition. There was a general increase in sap flow velocity as trees produced leaves over the growing season, but the increase in sap flow for trees without insecticide protection was half that of the protected trees (increase: 4.4 vs. 9.0 cm/h, respectively). This dramatic effect on sap flow was consistent with effects on crown condition. Unprotected trees had 20% less leaf mass per unit stem in the crown. In addition, unprotected trees had a 20% greater loss of leaf functional area from necrosis. It should be noted that these effects were detected in a year in which there was not an outbreak of the psyllids (Homoptera) that commonly cause severe leaf damage to this tree species. It is predicted that the effect in a psyllid outbreak year would be even more substantial. This result underscores the significant impact that insect herbivores can have on an ecological process of significance to the ecosystem, namely, the movement

  15. [Effect of pine plantations on soil arthropods in a high Andean forest].

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    León-Gamboa, Alba Lucía; Ramos, Carolina; García, Mary Ruth

    2010-09-01

    One of the most common problems in the Colombian mountains has been the replacement of native vegetation by pine plantations. Soil arthropods are a fundamental component of forest ecosystem, since they participate in the organic matter fragmentation, previous to decomposition. This role is more valuable in high altitude environments, where low temperatures limit the dynamics of biological processes, where the effects of pine plantations on soil arthropods are still not well-known. In a remnant of high-andean forest (Neusa - Colombia) and a pine plantation of about 50 years-old, it was evaluated the composition, richness and abundance of arthropods at surface (S), organic horizon (O) and mineral horizon (A) of soil, to establish the differences associated to the soil use transformation. It was used "Pitfall" sampling to register the movement of the epigeous fauna, and extraction by funnel Berlese for determining the fauna density from O and A horizons. The Shannon and Simpson indexes estimated the diversity at different places and horizons, and the trophic structure of the community was evaluated. Overall, there were collected 38 306 individuals from forest and 17 386 individuals from pine plantation, mainly distributed in Collembola (42.4%), Acari (27%), Diptera (17.6%) and Coleoptera (4.6%). The most important differences were given in the surface, where the mobilization in forest (86 individuals/day) almost triplicates the one in pine plantation (33 individuals/day). The differences in composition were given in Collembola, Araneae, Hemiptera, Homoptera and Hymenoptera. The dynamics of richness and abundance along the year had significant high values in the native forest than in the pine plantation. The general trophic structure was dominated by saprophagous (75%), followed by predators (14%) and phytophagous (9%), but in two layers of the pine plantation soil (S and O) this structural pattern was not given. Based on the results, it was concluded that pine

  16. Inseticidas seletivos à tesourinha Doru luteipes (Scudder utilizados no controle do pulgão verde em brássicas

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    Bacci Leandro

    2002-01-01

    Full Text Available Estudou-se a seletividade dos inseticidas acefato, deltametrina, dimetoato, metamidofós, paratiom metílico e pirimicarbe a ninfas de último estádio de Myzus persicae (Sulzer (Homoptera: Aphididae, em relação a adultos, ninfas de primeiro, segundo e terceiro estádios de Doru luteipes (Scudder (Dermaptera: Forficulidae. Pirimicarbe foi altamente seletivo em favor de todos os estádios do predador, sendo que os demais inseticidas foram medianamente seletivos em favor de adultos do predador. Deltametrina, paratiom metílico e dimetoato foram medianamente seletivos em favor de ninfas de terceiro estádio de D. luteipes, sendo que o mesmo ocorreu com os dois primeiros destes em relação a ninfas de primeiro e segundo estádios, respectivamente. Acefato foi pouco seletivo em favor de ninfas de segundo e terceiro estádios, sendo que o mesmo ocorreu com paratiom metílico, deltametrina e metamidofós em relação a ninfas de primeiro, segundo e terceiro estádios, respectivamente. Dimetoato e metamidofós foram mais tóxicos a ninfas de primeiro e segundo estádios do predador do que ao pulgão, sendo que o mesmo ocorreu com o acefato para ninfas de primeiro estádio. Adultos e ninfas de segundo e terceiro estádios de D. luteipes foram mais tolerantes ao acefato, paratiom metílico e pirimicarbe do que ninfas de primeiro estádio do predador. Ninfas de primeiro e segundo estádios apresentaram tolerância semelhante a deltametrina, dimetoato e metamidofós. As curvas de concentração-mortalidade de deltametrina, metamidofós e pirimicarbe (para todos os estádios de desenvolvimento de D. luteipes, dimetoato (para adultos e ninfas de primeiro e segundo estádios, paratiom metílico (para ninfas de primeiro e terceiro estádio e acefato (para adultos, apresentaram maiores inclinações do que as curvas destes inseticidas para M. persicae.

  17. Metodología para la evaluación del potencial insecticida de especies forestales.

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    Morales Soto León

    2000-06-01

    Full Text Available La diversidad florística de Colombia plantea enormes retos de investigación, con miras a una utilización racional e integral de sus recursos forestales. Las plantas con efectos biocidas utilizables en el control de plagas o enfermedades revisten una singular importancia. El objetivo de este trabajo es plantear una metodología de fácil aplicación, bajo costo y rápidos resultados, que permita acopiar la información necesaria sobre el mayor número de especies con potencial en este sentido. La metodología plantea la siguiente secuencia: selección de las especies vegetales de interés, apoyada en los reportes bibliográficos, conocimiento ancestral y observaciones personales; recolección del material en el campo; preparación del extracto total a partir del material seco; pruebas iniciales con Artemia salina Lech. para detectar actividad biológica, a través de la determinación de la LC50 (las especies con LC50 menores de 1000 ppm se consideran promisorias y ameritan procesos posteriores de fraccionamiento químico, bioensayos con las sustancias más promisorias sobre algún organismo de interés particular y determinación final de los compuestos activos en la planta. La metodología descrita fue empleada en la evaluación del potencial de acción biocida de 5 especies arbóreas o arbustivas, Guarea guidonia (L. Sleumer y Trichia hirta L. (Meliaceae, Machaerium moritzianum Benth. (Fabaceae, Swinglea glutinosa Merrill. (Rutaceae y Mammea americana L. (Clusiaceae. Se utilizó para los bioensayos iniciales el microcrustáceo Artemia salina Leach como indicador del potencial biocida con el fin de seleccionar las dos especies más promisorias a partir de las LC50 obtenidas. Con las dos se realizaron los bioensayos para evaluar la acción fagoinhibidora en la hormiga arriera Atta cephalotes (L., y el posible control de Alconeura sp. (Homoptera: Cicadellidae, insecto chupador que afecta la ceiba verde Pseudobombax septenatum (Jacq. Dugand

  18. Leafhoppers and Cixiids in Phytoplasma-infected Carrot Fields: Species Composition and Potential Phytoplasma Vectors

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    Tanja Drobnjaković

    2010-01-01

    Full Text Available The first molecular analysis of samples collected in southern Bačka (Serbia confirmed the presence of aster yellows (16SrI and stolbur phytoplasmas (16SrXII in insects belonging to the family Cicadellidae, as well as in carrot plants where the insects were collected. A correct identification of the phytoplasmas and their vectors is essential to arrange effective control strategies to prevent diseases associated with phytoplasmas from spreading to carrots and other vegetable crops. In order to enhance knowledgeabout insect vectors of aster yellows and stolbur phytoplasmas in Serbia, Cicadellidae and Cixiidae (Homoptera Auchenorrhyncha, the most common vectors of these phytoplasmas,were monitored in southern Bačka during 2008. Adults leaf- and planthoppers were collected and identified at species level using standard entomological methods,and tested for phytoplasma presence by means of PCR/RFLP. A total of 13 insect species of Cicadellidae were identified, as follows: a three species of the subfamily Agallinae: Anaceratagallia ribauti (Ossiannilsson, Anaceratagallia venosa (Fourcroy,and Anaceratagallia laevis (Ribaut; b seven species of the subfamily Deltocephalinae: Psammotettix confinis (Dahlbom, Psammotettix striatus (Linnaues Psammottettix alienus (Dahlbom, Macrosteles sexnotatus (Fallén, Ophiola decumana (Kontkanen,Errastunus ocellaris Fallén, and Scaphoideus titanus Ball; c three species of the subfamily Typhlocibinae: Eupteryx atropunctata (Goeze, Eupteryx mellissae Curtis, Zyginidia pullula (Boheman. Female specimens of the genus Euscelis (Deltocephalinae were also collected, as well as one species of Reptalus quinquecostatus (Dufour of the family Cixiidae. Stolbur phytoplasmas were detected in A. laevis, A. ribauti, A. venosa, P. striatus, P. confinis and P. alienus. The species: A. laevis, O. decumana, and P. confinis were AY-infected (subgroup 16SrI-A, while subgroup 16SrI-C was found only in one specimen of P. confinis. Since some

  19. The phytosanitary form and fighting measures diseases and pests of sugar beet from Republic of Moldova

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    Timus Asea M.

    2006-01-01

    Full Text Available Sugar beet is one of the most important agricultural crops in the Republic of Moldova. The North and Central regions have good enough pedoclimatic conditions. The genetic potential of sorts and hybrids can be created through the application of modern technologies in order to grow at least 32-35 tons/ha of sugar beet roots. In the Republic of Moldova, sugar beet vegetates between 160 and 180 days in the first year and needs approximately an amount of 2400-2900°C, average of 15.3-15.4°C. Each phenological phase needs different temperatures: at least 4C° is necessary for planting and springing an amount of 650°C is necessary for foliar apparatus; an amount of 1150- 1800°C is necessary to grow the volume of roots and for sugar depositing the average of 2400 to 2600°C is necessary. The mentioned temperatures ensure a normal development of sugar beet plants. If these temperatures fluctuate, the pathogens and pests are stimulated to develop. The most frequent diseases of sugar beet are: Pythium de baryanum Hesse., Aphanomyces cochlioides Dresch. Peronospora schachtii Fuck., Phoma betae Fr. Cercospora beticola Sacc. Erysiphe communis Grev. f. betae Jacz., virosis - Beta virus 2, 3 si 4 etc. The main pests belong to the following categories: Homoptera: Aphis fabae Scop. (fam. Aphididae, Pemphigus fuscicornis Koch. (fam. Pemphigidae Coleoptera: Agriotes sp. (fam. Elateridae, Chaetocnema concinna M. Ch. breviuscula Fld., Cassida nebulosa L. (fam. Chrysomelidae, Atomaria linearis Step. (fam. Cryptophagidae; Bothynoderes punctiventris Germ., Tanymechus dilaticollis Gyll., T. palliatus F., Psalidium maxillosum F. (Curculionidae; Lepidoptera: Agrotis segetum Den. et Schiff., Authographa gamma L. Mamestra (Barathra brassicae L. (Noctuidae, Loxostege sticticalis L. (Pyralidae, Gnorimoschema ocellatella Boyd.; Diptera Pegomyia betae Curtis. (fam. Anthomyidae. Heterodera schachtii Schmidt (Heteroderidae. The most recommended insecticides for fighting the

  20. Study of microarthropod communities to assess soil quality in different managed vineyards

    Science.gov (United States)

    Gagnarli, Elena; Vignozzi, Nadia; Valboa, Giuseppe; Bouneb, Mabrouk; Corino, Lorenzo; Goggioli, Donatella; Guidi, Silvia; Lottero, Mariarosa; Tarchi, Franca; Simoni, Sauro

    2014-05-01

    conventional/IPM management). The mites represented about 50% of the arthropodofauna recorded, collembolans 30%, and 20% other microarthropods (Blattaria, Chilopoda, Coleoptera, Diplopoda, Diplura, Diptera, Hemiptera, Hymenoptera, Isopoda, Homoptera, Pauropoda, Protura, Pseudoscopionida, Psocoptera, Symphyla, Thysanoptera). The mesofauna abundance was affected by the type of management (P=0.015) and soil texture (P=0.029). At the identification level considered, the biological indices calculated showed no substantial differences between different crop managements (H'=1.26, D=0.97 in organic vineyard, H'=1.30, D=0.89 in IPM vineyard). The analysis of microarthropod communities by QBSar, however, showed higher values in organic compared to IPM managed vineyards (QBSar 199 vs 98 in 2011 and 205 vs 188 in 2012, respectively) which are close to figures characteristic of preserved soils.

  1. Resistência de clones de batata a Bemisia tabaci biótipo B Resistance of potato clones to Bemisia tabaci biotype B

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    Artur BO Rocha

    2012-03-01

    Full Text Available Avaliou-se a resistência de 30 genótipos de batata a B. tabaci (Genn. biótipo B (Hemiptera: Aleyrodidae em casa de vegetação, por meio de três experimentos. No primeiro com chance de escolha, foi em blocos ao acaso, 30 tratamentos e três repetições. Avaliou-se a atratividade para adultos, a preferência para oviposição e a densidade de tricomas simples e glandulares. Os sete genótipos com menor oviposição, juntamente com o padrão de resistência 'Achat', e o mais ovipositado foram selecionados para os experimentos seguintes, nos quais se avaliou a preferência para oviposição sem chance de escolha e para o acompanhamento do período de desenvolvimento ovo-adulto, ambos em blocos ao acaso, nove tratamentos e cinco repetições. Na avaliação de atratividade, após 72 horas, HPC 5B e BAP 82 tiveram o menor número de adultos, enquanto que NYL 235-4 e MAC 2 foram os mais atrativos. Neste mesmo experimento, os genótipos HPC 6R, BACH 4, Clone APTA 2135, HPC 9B, BAP 82, 'Baraka' e HPC 5B foram os menos ovipositados. O genótipo NYL 235-4 mostrou alta densidade de tricomas simples (TS e glandulares (TG, enquanto os genótipos CH 2, 'Santé' e 'Caesar' tiveram alta densidade de TS, e HPC 9B, 'Radosa', 'Cupido', 'Caesar', 'Saginaw Gold', BACH 3 e HPC 1B para TG revelaram menor pilosidade. Houve correlação significativa entre atratividade para adultos e preferência para oviposição. No experimento sem chance de escolha, os genótipos BACH 4, HPC 9B, 'Baraka' e 'Achat' foram menos ovipositados, caracterizando-se como portadores de resistência do tipo não-preferência para oviposição. Quanto ao período de desenvolvimento ovo-adulto, as médias não diferiram entre os genótipos, variando de 34,4 a 36,6 dias. Observou-se para os genótipos BAP 82, 'Baraka' e BACH 4 o menor número de adultos emergidos, sugerindo a presença de antibiose. Com base nos três experimentos, os clones 'Baraka' e BACH 4 destacaram-se como os mais

  2. Recolecta de artrópodos para prospección de la biodiversidad en el Área de Conservación Guanacaste, Costa Rica

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    Vanessa Nielsen

    2004-03-01

    Full Text Available Desde 1994 hasta 1997, 1800 muestras de artrópodos correspondientes a 642 especies distribuidas en 21 órdenes y 95 familias fueron recolectadas en 21 localidades protegidas del Área de Conservación Guanacaste, para ser estudiadas como fuente potencial de nuevos medicamentos. Las localidades con más recolectas fueron Santa María (231 spp.; 421 muestras, Santa Rosa (110 spp.; 172 muestras, Cacao (98 spp.; 203 muestras y Pitilla (67 spp.; 79 muestras, siendo la mayor cantidad recolectadas durante la estación lluviosa. El 49.72% de las muestras recolectadas correspondió al orden Lepidoptera, 15.75% a Coleoptera, 13.33% a Hymenoptera, 11.43% a Orthoptera, 6.75% a Hemiptera, 3.20% a Homoptera y 7.89% a otros grupos. Además, un 54.26% de las muestras correspondía a individuos adultos, 19.90% a larvas, 11.20% a estiércol, 6.46% a pupas, 6.12% a prepupas, 2.07% a ninfas y 3.74% a otros estadios. Un 44.38% de las muestras se recolectó mediante recolecta manual, seguido por crianza de insectos (25.73%, trampa de luz (18.80%, diferentes tipos de redes (10.52% y otros métodos (0.16%. La alta diversidad de los trópicos y la gran abundancia de artrópodos hace de este grupo una fuente potencial de productos farmacéuticos. Sin embargo, se debe evitar la recolecta intensiva en la misma localidad durante años consecutivos (sobre todo hembras, minimizar la interferencia en procesos vitales de los organismos y la dinámica de sus poblaciones. Además se debe recolectar la menor cantidad posible de individuos y escoger la época del año adecuada, para lograr el reestablecimiento natural de las poblacionesThis study describes the results and collection practices for obtaining arthropod samples to be studied as potential sources of new medicines in a bioprospecting effort. From 1994 to 1998, 1800 arthropod samples of 6-10 g were collected in 21 sites of the Área de Conservación Guancaste (A.C.G in Northwestern Costa Rica. The samples corresponded to

  3. Effects of insecticides used in Bemisia tabaci (Gennadius biotype B control and their selectivity to natural enemies in soybean cropEfeitos dos inseticidas utilizados no controle de Bemisia tabaci (Gennadius biótipo B e sua seletividade aos inimigos naturais na cultura da soja

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    Simone Silva Vieira

    2012-10-01

    Full Text Available In recent crop seasons, the whitefly, Bemisia tabaci biotype B has become a serious pest in soybean crops due to high infestations and its control difficulties. Therefore, it is important to search control alternatives in the integrated pest management approach. Thus, it was evaluated in this study the efficacy of the whitefly control using different insecticides in greenhouse conditions and their selectivity to the parasitoids Encarsia formosa, Trichogramma pretiosum and Telenomus remus. Buprofezin 150 g. a.i.ha-1 + mineral oil 0.2% v/v and pyriproxyfen 100 g. a.i.ha-1 were considered the best options for the whitefly management due to combine good pest control efficacy with higher selectivity to the parasitoids except Encarsia formosa for which no treatment was classified as harmless. Betacyflutrin 9.375 + imidacloprid 75 g. i.a. ha-1 was efficient on controlling whiteflies nymphs but was not harmless to the studied natural enemies. In general, the treatments including pyretroids compounds (betacyflutrin 9.375 + imidacloprid 75 + spiromesifen 60, betacyflutrin 9.375 + imidacloprid 75 and lambda-cyhalothrin 26.5 + thiametoxan 35.25 g. a.i. ha-1 were the most harmful to the evaluated parasitoids and therefore it use should be avoid whenever possible. Nas últimas safras a mosca-branca, Bemisia tabaci biótipo B (Hemiptera: Aleyrodidae tornou-se praga de importância econômica para a cultura da soja devido à ocorrência de altas infestações e à dificuldade de controle desta praga. Sendo assim, é importante buscar alternativas de manejo com base em um programa de manejo integrado de pragas. Assim, avaliaram-se neste trabalho a eficiência de diferentes inseticidas no controle da mosca-branca em casa-de-vegetação e a seletividade destes aos parasitoides Encarsia formosa, Trichogramma pretiosum e Telenomus remus. Buprofezina 150 g i.a. ha-1 + óleo mineral 0,2% v/v e piriproxifem 100 g. i.a. ha-1 foram consideradas as melhores opções para

  4. A survey of homopteran species (Auchenorrhyncha from coffee shrubs and poró and laurel trees in shaded coffee plantations, in Turrialba, Costa Rica

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    Liliana Rojas

    2001-12-01

    Full Text Available Asurvey of homopteran species (Auchenorryncha was conducted in coffee plantations with no shade (C, and in those with shade of either poró (Erythrina poeppigiana (CP or poró plus laurel (Cordia alliodora (CPL, in Turrialba, Costa Rica. A total of 130 species in ten families were collected, dominated by Cicadellidae (82 species. Species richness was highest in the CP system (88, followed by CPL (74 and C systems (60. Five most common species for all systems were Fusigonalia lativittata, Hebralebra nicaraguensis, Neocoelidia sp., Oliarus sp. and Clastoptera sp. Diversification of the coffee agroecosystem favors some species while limiting others, and have no effect on the majority of species. Thus, only F. lativittata, Neocoelidia sp. and Scaphytopius ca. latidens were well represented in all systems, but were more abundant in coffee shrubs. Additionally, the following were the dominant species in each system: Graphocephala sp. 1 (C, F. lativittata (CP and H. nicaraguensis (CPL. Four species abundant on laurel trees, including H. nicaraguensis, appeared almost exclusively on these tree species. Species similarity was highest on the CP and CPL systems (51 % of the species in common, followed by the C and CP (39 % and the C and CPL systems (38 %. These findings show that even disturbed systems can harbor many insect species, so that they deserve attention from conservation advocatesand biologistsEn Turrialba, Costa Rica, se efectuó un inventario de especies de chicharritas (Homoptera: Auchenorryncha en plantaciones de café sin sombra (C, así como en café asociado con árboles de poró (Erythrina poeppigiana (CP o de poró y laurel (Cordia alliodora (CPL. Se recolectaron 131 especies, pertenecientes a diez familias, entre las cuales predominó Cicadellidae (82 especies. La riqueza de especies fue mayor para el sistema CP (88 especies, seguido por CPL y C, con 74 y 60 especies, respectivamente. Las cinco especies más comunes para los tres

  5. Resultados preliminares obtenidos a partir de una trampa Malaise situada en una zona mediterránea pirenaica

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    Pujade, J.

    1996-12-01

    Full Text Available In this article data about the several Orders of arthropods captured using a Malaise trap, at Santa Coloma (Andorra, after a one-year cycle is reported. Up to 141.522 specimens have been collected, belonging to 20 different Orders. About 99.5% of the captures are insects, of which 74.1°/o are Diptera, 15.2% are Hymenoptera and 5.8% are Homoptera. These three groups together represent 95% of the arthropods. Annual phenology of the different groups and their relationship with the weather is discussed. Generally, the peaks of abundance of the main groups are registered in the second stage of the spring and the first one of the summer. It is due to the xerothermic conditions of the locality.

    [es] En este estudio se da cuenta de los distintos órdenes de artrópodos capturados mediante una trampa Malaise en Santa Coloma (Andorra después de un año de muestreo. Han sido colectados 141.522 ejemplares pertenecientes a 20 órdenes distintos. El 99,5% corresponden a insectos, entre los cuales los dípteros (con el 74,1%, juntamente con los himenópteros (15,2% y los homópteros (5,8% constituyen más del 95% de las capturas realizadas. Se discute la fenología anual de los distintos grupos en el área de estudio y su relación con las circunstancias meteorológicas del año 1993. En general, las mayores abundancias de los principales grupos se registran entre la segunda mitad de la primavera y la primera mitad del verano debido a las condiciones xerotérmicas de dicha localidad.
    [fr] On montre les premiers résultats obtenus après avoir mis une piège Malaise pendant une année à Santa Coloma (Andorra. Nous avons collecté un total de 141.522 exemplaires qui appartiennent à 20 ordres différents d'arthropodes. Le 99,5% des captures sont des insectes, les diptères (avec le 74,1%, en même temps que les hyménoptères (avec le 15,2% et les homoptères (5,8% représentent plus du 95% des captures. On parle de la phénologie annuel des diff

  6. Plantas hospederas de Aphis gossypii (Aphididae, vector de virus del melón Cucumis melo (Cucurbitaceae en Costa Rica

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    M.V. Sánchez

    2001-03-01

    Full Text Available Se identificaron las especies hospederas naturales de Aphis gossypii Glover (Aphididae: Homoptera en plantaciones comerciales de melón para la exportación en Costa Rica. El estudio se realizó en dos fincas, ubicadas una en la provincia de Guanacaste y la otra en la provincia de Puntarenas, correspondientes a dos zonas de vida vegetal diferentes. Se identificaron como especies hospederas del áfido todas aquellas especies vegetales en las que se observó la presencia del áfido en su forma áptera. En ambas fincas el estudio se realizó en los alrededores y dentro del cultivo de melón. En la finca A en cinco diferentes comunidades vegetales (cultivo, canal de drenaje, charral, potrero mejorado y semi-bosque previamente seleccionadas y en la finca B en cuatro comunidades vegetales (cultivo, charral, pastizal natural y semi-bosque. Especímenes de las plantas colonizadas por áfidos y los áfidos colonizadores de cada especie fueron recolectadas para su identificación. Los áfidos se preservaron en alcohol al 70% v/v e identificaron utilizando las claves taxonómicas para áfidos, confirmándose como especie dominante a A. gossypii. La diversidad, cobertura y época de aparición de las especies de plantas hospederas fue monitoreada durante un año calendario en las diferentes comunidades vegetales presentes en ambas fincas, observándose diferencias entre las dos fincas estudiadas. En la finca A se observaron 86 diferentes especies vegetales, pertenecientes a 49 familias, asociadas al cultivo del melón, mientras que en la finca B se identificaron 72 especies de 40 familias. En conjunto para ambas fincas, un de 24 especies de plantas (16 familias estaban colonizadas por el áfido A. gossypii. De éstas, 16 especies de 10 familias, son reportes nuevos de plantas hospederas para este áfido: Justicia comata, Tetramerium nervosum, Alternanthera pubiflora, Cassia massoni, C. reticulata, Cleome viscosa, C. spinosa, Croton argenteus, Caperonia

  7. Grassland birds wintering at U.S. Navy facilities in southern Texas

    Science.gov (United States)

    Woodin, Marc C.; Skoruppa, Mary Kay; Bryan, Pearce D.; Ruddy, Amanda J.; Hickman, Graham C.

    2010-01-01

    transects during the study were Species of Conservation Concern: Le Conte’s Sparrow, Sedge Wren (Cistothorus platensis), Grasshopper Sparrow (Ammodramus savannarum), Long-billed Curlew (Numenius americanus), Sprague’s Pipit (Anthus spragueii), Cassin’s Sparrow (Aimophila cassinii), and Loggerhead Shrike (Lanius ludovicianus). Native grasslands consistently supported greater bird species richness than exotic grasslands. In one winter, exotic grasslands supported more birds than native grasslands.Native grasslands were determined to have more forb cover, more bare ground, and greater plant species richness than exotic grasslands, whereas exotic grasslands were characterized by more grass cover and relatively greater vegetation density during dry years. Not only did these individual measures differ between native and exotic grasslands, but components of variation also differed. In native grasslands, grass density and cover contributed more to variation, whereas in exotic grasslands, non-grass vegetation was a greater component of variation. Total bird numbers and bird species richness in native grasslands were related to the principal component that contained a measure of litter cover. Total bird numbers and bird species richness in exotic grasslands indicated no significant relationships with any of the principal components of variation.The two most common insect orders in native grasslands were Hymenoptera and Coleoptera, which accounted for 42 percent of all insects. The two most common insect orders in exotic grasslands were Hemiptera and Homoptera, which accounted for about 80 percent of all insects. Insect family richness was greater in exotic grasslands than in native grasslands in two of four seasons. Proportions of arachnid families were similar in native and exotic grasslands, but arachnid family richness was greater in exotic grasslands than in native grasslands.Abundance of seeds was greater in exotic than in native grasslands. However, seed diversity was