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Sample records for meloidogyne incognita population

  1. Effect of a Terminated Cover Crop and Aldicarb on Cotton Yield and Meloidogyne incognita Population Density.

    Science.gov (United States)

    Wheeler, T A; Leser, J F; Keeling, J W; Mullinix, B

    2008-06-01

    Terminated small grain cover crops are valuable in light textured soils to reduce wind and rain erosion and for protection of young cotton seedlings. A three-year study was conducted to determine the impact of terminated small grain winter cover crops, which are hosts for Meloidogyne incognita, on cotton yield, root galling and nematode midseason population density. The small plot test consisted of the cover treatment as the main plots (winter fallow, oats, rye and wheat) and rate of aldicarb applied in-furrow at-plant (0, 0.59 and 0.84 kg a.i./ha) as subplots in a split-plot design with eight replications, arranged in a randomized complete block design. Roots of 10 cotton plants per plot were examined at approximately 35 days after planting. Root galling was affected by aldicarb rate (9.1, 3.8 and 3.4 galls/root system for 0, 0.59 and 0.84 kg aldicarb/ha), but not by cover crop. Soil samples were collected in mid-July and assayed for nematodes. The winter fallow plots had a lower density of M. incognita second-stage juveniles (J2) (transformed to Log(10) (J2 + 1)/500 cm(3) soil) than any of the cover crops (0.88, 1.58, 1.67 and 1.75 Log(10)(J2 + 1)/500 cm(3) soil for winter fallow, oats, rye and wheat, respectively). There were also fewer M. incognita eggs at midseason in the winter fallow (3,512, 7,953, 8,262 and 11,392 eggs/500 cm(3) soil for winter fallow, oats, rye and wheat, respectively). Yield (kg lint per ha) was increased by application of aldicarb (1,544, 1,710 and 1,697 for 0, 0.59 and 0.84 kg aldicarb/ha), but not by any cover crop treatments. These results were consistent over three years. The soil temperature at 15 cm depth, from when soils reached 18 degrees C to termination of the grass cover crop, averaged 9,588, 7,274 and 1,639 centigrade hours (with a minimum threshold of 10 degrees C), in 2005, 2006 and 2007, respectively. Under these conditions, potential reproduction of M. incognita on the cover crop did not result in a yield penalty.

  2. Screening of Carnation Cultivars for Resistance to Meloidogyne incognita.

    Science.gov (United States)

    Cho, M R; Kim, J Y; Song, C; Ko, J Y; Na, S Y; Yiem, M S

    1996-12-01

    A total of 33 carnation cultivars cultured in Korea were screened for resistance to the southern root-knot nematode, Meloidogyne incognita. Carnations were tested by either inoculating with 5,000 eggs or by transplanting into a mixture of bedding medium and soil infested with an average of 435 second-stage juveniles/300 cm(3) soil. Cultivars, Desio, Castelaro, Kappa, Rara, Izu Pink, Target, and Antalia were highly resistant to M. incognita. Twelve cultivars were moderately resistant, and the remaining 14 cultivars were susceptible. These results were similar to those obtained when the cultivars were subjected to field populations of the condition on a carnation farm.

  3. Adaptação hospedeira de variedades de abacaxi a meloidogyne incognita raça 1 Host suitability of pineapple varieties for meloidogyne incognita race 1

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    Leila Lucí Dinardo-Miranda

    1996-01-01

    Full Text Available Avaliou-se, em campo naturalmente infestado, a adaptação hospedeira das variedades de abacaxi Smooth Cayenne, Abacaxi-de-gomo, Bico-de-rosa, Boituva, Guiana, Huitota, Manzana, Natal Queen, Pérola, Perolera, Rondon, Roxo-de-Tefé e Turi Verde a Meloidogyne incognita raça 1. Somente 'Huitota' apresentou populações do nematóide significativamente menores que aquelas encontradas na 'Smooth Cayenne', considerada boa hospedeira da espécie.The host suitability of thirteen pineapple varieties, namely Smooth Cayenne, Abacaxi-de-gomo, Bico-de-rosa. Boituva, Guiana, Huitota, Manzana, Natal Queen, Pérola, Perolera, Rondon, Roxo-de-Tefé, and Turi Verde, for Meloidogyne incognita race I was evaluated under infested field conditions. Only 'Huitota' was considered poor host, showing significantly lower nematode population than 'Smooth Cayenne', known as a good host to M. incognita.

  4. Screening of Carnation Cultivars for Resistance to Meloidogyne incognita

    OpenAIRE

    Cho, M. R.; Kim, J. Y.; Song, C.; Ko, J.Y.; Na, S. Y.; Yiem, M. S.

    1996-01-01

    A total of 33 carnation cultivars cultured in Korea were screened for resistance to the southern root-knot nematode, Meloidogyne incognita. Carnations were tested by either inoculating with 5,000 eggs or by transplanting into a mixture of bedding medium and soil infested with an average of 435 second-stage juveniles/300 cm³ soil. Cultivars, Desio, Castelaro, Kappa, Rara, Izu Pink, Target, and Antalia were highly resistant to M. incognita. Twelve cultivars were moderately resistant, and the re...

  5. Virulence of Meloidogyne incognita to expression of N gene in pepper

    Science.gov (United States)

    Five root-knot nematode resistant pepper genotypes and three susceptible pepper genotypes were compared for their reactions against a population of Meloidogyne incognita (Chitwood) Kofoid and White which had been shown to be pathogenic to bell pepper (Capsicum annuum) in preliminary tests. The pepp...

  6. Development of virulence to Meloidogyne incognita on resistant pepper rootstocks

    Energy Technology Data Exchange (ETDEWEB)

    Ros-Ibanez, C.; Robertson, L.; Martinez-Lluch, M. C.; Cano-Garcia, A.; Lacasa-Plasencia, A.

    2014-06-01

    The root-knot nematode (RKN) Meloidogyne incognita is a major soil parasite of pepper crops in greenhouses in Southeast Spain. Due to the limitations of the use of soil fumigants, grafting plants on resistant rootstocks (R-rootstocks) has become an important alternative to chemical nematicides. The repeated use of R-rootstocks can bring about the selection of virulent populations capable of overcoming resistance. We carried out a six-year investigation on resistant rootstocks in a naturally M. incognita infested greenhouse, and found that two successive years of growing plants grafted on R-rootstocks Atlante (ATL) were sufficient to overcome resistance (galling index 1.5 and 5.6 in the first and second years respectively). A large variability was observed between several R-rootstocks. Two R-rootstocks (C19 and Snooker) behaved like ATL while two others (Terrano and DRO 8801) were not infected by RKN. Laboratory studies with the same R-rootstocks, inoculated with two nematode isolates (avirulent and virulent against ATL) confirmed the greenhouse results, indicating that some rootstocks may be infested by virulent populations and others may not. It suggests that different R-genes, which are differentially overcome by RKN, have been introgressed into the rootstocks. This may have consequences for the management of resistant rootstocks in the field. (Author)

  7. Development of virulence to Meloidogyne incognita on resistant pepper rootstocks

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    C. Ros Ibáñez

    2014-02-01

    Full Text Available The root-knot nematode (RKN Meloidogyne incognita is a major soil parasite of pepper crops in greenhouses in Southeast Spain. Due to the limitations of the use of soil fumigants, grafting plants on resistant rootstocks (R-rootstocks has become an important alternative to chemical nematicides. The repeated use of R-rootstocks can bring about the selection of virulent populations capable of overcoming resistance. We carried out a six-year investigation on resistant rootstocks in a naturally M. incognita infested greenhouse, and found that two successive years of growing plants grafted on R-rootstocks Atlante (ATL were sufficient to overcome resistance (galling index 1.5 and 5.6 in the first and second years respectively. A large variability was observed between several R-rootstocks. Two R-rootstocks (C19 and Snooker behaved like ATL while two others (Terrano and DRO 8801 were not infected by RKN. Laboratory studies with the same R-rootstocks, inoculated with two nematode isolates (avirulent and virulent against ATL confirmed the greenhouse results, indicating that some rootstocks may be infested by virulent populations and others may not. It suggests that different R-genes, which are differentially overcome by RKN, have been introgressed into the rootstocks. This may have consequences for the management of resistant rootstocks in the field.

  8. Nematicide and nematostatic potential of Curcuma longa on Meloidogyne incognita

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    Thaísa Muriel Mioranza

    2016-08-01

    Full Text Available The root knot nematodes can reduce yield potential of plants, thus requiring searching control methods that are effective and eco-friendly. The purpose of this study was to analyze the efficiency of turmeric rhizome aqueous extract (Curcuma longa on hatching, immobilization and mortality of juveniles of Meloidogyne incognita. A completely randomized design was used, with concentrations of 1%, 5%, 10% and 15% of turmeric extract and distilled water as a control treatment, with four replications. The juveniles of nematodes were directly exposed to turmeric extract for 24 h, while eggs were exposed during 15 days. The turmeric extract on J2 of Meloidogyne incognita, in vitro tests, promoted from the concentration of 10% total paralysis of nematodes and in the concentration of 15% more than 90% mortality. All tested concentrations caused reduction in juveniles hatching. Thereby, the turmeric aqueous extract has nematicidal potential against M. incognita, encouraging its study in the interaction plant-nematode.

  9. Tagetes Patula y T Erecta para Controlar Meloidogyne Incognita y Hellcotylenchus Dihystera

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    Vergel German

    1979-06-01

    Full Text Available An experiment was carried out under greenhouse conditions to test the control of Meloidogyne incognita and Helicotylenchus dihystera by Tagetes patula nana var. Petit Harmony and T. erecta var. Orange. For each of these nematode species, the population levels tested were considered as high, moderate and low. These populations were obtained mixing infested soil with sterilized one. Both Tagetes species gave satisfactory control. The decrease in population of nematodes in comparison with tomato was ranged from 15.5 to 136.3% depencing on the nematode species and on its population level on the soil No significate difference was found between the two Tagetes species. There was a greater decrease in population density for M. incognita than for H. dihystera; this was particulary true at the lowest population levels tested. In the case of M. incognita, an inverse relation was found between degree of control and population density of these nematodes in soil.

  10. Reproduction of Meloidogyne incognita on Winter Cover Crops Used in Cotton Production.

    Science.gov (United States)

    Timper, Patricia; Davis, Richard F; Tillman, P Glynn

    2006-03-01

    Substantial reproduction of Meloidogyne incognita on winter cover crops may lead to damaging populations in a subsequent cotton (Gossypium hirsutum) crop. The amount of population increase during the winter depends on soil temperature and the host status of the cover crop. Our objectives were to quantify M. incognita race 3 reproduction on rye (Secale cereale) and several leguminous cover crops and to determine if these cover crops increase population densities of M. incognita and subsequent damage to cotton. The cover crops tested were 'Bigbee' berseem clover (Trifolium alexandrinum), 'Paradana' balansa clover (T. balansae), 'AU Sunrise' and 'Dixie' crimson clover (T. incarnatum), 'Cherokee' red clover (T. pratense), common and 'AU Early Cover' hairy vetch (Vicia villosa), 'Cahaba White' vetch (V. sativa), and 'Wrens Abruzzi' rye. In the greenhouse tests, egg production was greatest on berseem clover, Dixie crimson clover, AU Early Cover hairy vetch, and common hairy vetch; intermediate on Balansa clover and AU Sunrise crimson clover; and least on rye, Cahaba White vetch, and Cherokee red clover. In both 2002 and 2003 field tests, enough heat units were accumulated between 1 January and 20 May for the nematode to complete two generations. Both AU Early Cover and common hairy vetch led to greater root galling than fallow in the subsequent cotton crop; they also supported high reproduction of M. incognita in the greenhouse. Rye and Cahaba White vetch did not increase root galling on cotton and were relatively poor hosts for M. incognita. Only those legumes that increased populations of M. incognita reduced cotton yield. In the southern US, M. incognita can complete one to two generations on a susceptible winter cover crop, so cover crops that support high nematode reproduction may lead to damage and yield losses in the following cotton crop. Planting rye or Meloidogyne-resistant legumes as winter cover crops will lower the risk of increased nematode populations

  11. Nematicide and nematostatic potential of Curcuma longa on Meloidogyne incognita

    OpenAIRE

    Thaísa Muriel Mioranza; Mônica Anghinoni Müller; Adriano Mitio Inagaki; Felipe Fuchs; Sidiane Coltro-Roncato; José Renato Stangarlin; Odair José Kuhn

    2016-01-01

    The root knot nematodes can reduce yield potential of plants, thus requiring searching control methods that are effective and eco-friendly. The purpose of this study was to analyze the efficiency of turmeric rhizome aqueous extract (Curcuma longa) on hatching, immobilization and mortality of juveniles of Meloidogyne incognita. A completely randomized design was used, with concentrations of 1%, 5%, 10% and 15% of turmeric extract and distilled water as a control treatment, with four replicatio...

  12. Reação de crisântemos a Meloidogyne incognita, Meloidogyne javanica e Meloidogyne enterolobii

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    Lucivane Aparecida Gonçalves

    2014-03-01

    Full Text Available Este trabalho teve como objetivo avaliar a resistência de 14 variedades de crisântemos aos nematoides Meloidogyne incognita, M. javanica e M. enterolobii. O experimento foi conduzido em delineamento inteiramente casualizado, constando de 15 tratamentos e 4 repetições, por espécie de nematoide. Cada parcela foi constituída por uma planta por vaso, mantidas em casa de vegetação e inoculadas com 5.000 ovos e eventuais juvenis de M. incognita, M. javanica e M. enterolobii. Após 60 dias, os índices de massas de ovos, número de nematoides por grama de raiz e o fator de reprodução foram avaliados. As variedades apresentaram imunidade a M. incognita, M. javanica e M. enterolobii, exceto 'Capello Vermelho' e 'White Reagon', que foram respectivamente suscetível e resistente a M. incognita.

  13. [Control effects of Ricinus communis extracts on Meloidogyne incognita].

    Science.gov (United States)

    Gao, Qian-Yuan; Hu, Fei-Long; Zhu, Hong-Hong; Liu, Man-Qiang; Li, Hui-Xin; Hu, Feng

    2011-11-01

    Toxicity test and pot experiment were conducted to study the nematocidal activity and control effects of Ricinus communis extracts on Meloidogyne incognita. The results showed that both the ricinine and the R. communis water extracts had high nematocidal activity. The ricinine at concentration 2 g x L(-1) and treated for 48 hours had the strongest nematocidal activity, leading to 91.5% of corrected mortality of M. incognita and with the LC50 being 0.6 g x L(-1), whereas the R. communis water extracts at concentration 100 g x L(-1) and treated for 48 hours had the strongest nematocidal activity, which led to 83.5% of corrected mortality of M. incognita, and the LC50 was 18.3 g x L(-1). With the inoculation of M. incognita treated with ricinine, R. communis water extracts, and R. communis leaf powder, respectively, on tomato seedlings, the mean number of plant root-knots was 17.6 +/- 1.7, 20.6 +/- 1.5 and 22.8 +/- 3.7, respectively, being significantly lower than the control (37.4 +/- 2.3), and the root length increased by 46.8%, 34.5% and 33.8%, and the plant height increased by 33.5%, 22.6% and 15.8%, and the fresh mass increased by 41.4%, 18.9% and 10.1%, respectively, compared with the control. All the results suggested that R. communis extracts could mitigate the harm of M. incognita, and had obvious effects on potted tomato against M. incognita.

  14. GRAFTING FOR CONTROL OF MELOIDOGYNE INCOGNITA ON BELL PEPPER, TOMATO, AND MELONS

    Science.gov (United States)

    Greenhouse, microplot, and field trials were conducted over three-years to evaluate rootstocks for root-knot nematode (Meloidogyne incognita) resistance. Rootstocks were evaluated for bell pepper (Capsicum annuum), tomato (Solanum esculentum), cantaloupe (Cucumis melo), and watermelon (Citrullus lan...

  15. Host status of progenies of yellow passion fruit to Meloidogyne incognita race 2

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    Roxana Stefane Mendes Nascimento

    2016-07-01

    Full Text Available The host status of eighteen progenies (CRP 01-12 to CRP 16-12, CRP 19-12 and CRP 20-12 and two cultivars (FB 200 Yellow Master and FB 300 Araguari of yellow passion fruit to Meloidogyne incognita race 2 was evaluated in a greenhouse experiment. The height and the biomass of the plants, besides the numbers of galls, eggs and second-stage juveniles in roots and soil were assessed after 70 days of cultivation of the genotypes and tomato (control in plastic pots with 2 kg of soil infested with 5,000 eggs of the nematode. The reproduction factor of the pathogen (RF = Final population/Initial population was calculated for classifying the genotypes as immune (RF = 0, resistant (RF < 1 or susceptible (RF ≥ 1. The cultivar FB 200 is resistant to M. incognita race 2 and can be cultivated in areas infested with this nematode.

  16. Behavioral differences of Heterodera glycines and Meloidogyne incognita infective juveniles exposed to root extracts in vitro

    Science.gov (United States)

    The in vitro behaviors of infective juveniles (J2) of Heterodera glycines and Meloidogyne incognita were compared in the presence and absence of plant root extracts. In an agar plate attraction-retention assay, H. glycines was 15-fold more responsive to a chemical attractant (CaCl2; P < 0.05) than w...

  17. Nematicidal activity of plant extracts against the root-knot nematode, Meloidogyne incognita

    NARCIS (Netherlands)

    Wiratno,; Taniwiryono, D.; Berg, van den J.H.J.; Riksen, J.A.G.; Rietjens, I.; Djiwanti, S.R.; Kammenga, J.E.; Murk, A.J.

    2009-01-01

    Nematicidal activity of extracts from plants was assayed against Meloidogyne incognita. In laboratory assays extracts from tobacco (Nicotiana tabacum L), clove (Syzygium aromaticum L), betelvine (Piper betle L), and sweet flag (Acorus calamus L) were most effective in killing the nematode, with an E

  18. Protease inhibition by Heterodera glycines cyst content: evidence for effects on the Meloidogyne incognita proteasome

    Science.gov (United States)

    Proteases from Heterodera glycines and Meloidogyne incognita juveniles were inhibited by heat-stable content of H. glycines female cysts (HglCE), and by the plant polyphenol epigallocatechin gallate (EGCG). General protease activities detected using the nematode peptide KSAYMRFa were inhibited by EG...

  19. Effects of benzyl isothiocyanate on the reproduction of Meloidogyne incognita on Glycine max and Capsicum annuum

    Science.gov (United States)

    Reproduction of Meloidogyne incognita on Capsicum annuum or Glycine max was suppressed when infective juveniles (J2) were exposed to 0.03 millimolar benzyl isothiocyanate (BITC) for 2hr prior to inoculation of the host. Infectivity assessed by gall index was significantly reduced on both G. max (co...

  20. Evaluation of repeated bio disinfestation using Brassica carinata pellets to control Meloidogyne incognita in protected pepper crops

    Energy Technology Data Exchange (ETDEWEB)

    Guerrero-Diaz, M. M.; Lacasa-Martinez, C. M.; Hernandez-Pinera, A.; Martinez-Alarcon, V.; Lacasa Plasencia, A.

    2013-06-01

    The nematode Meloidogyne incognita is responsible for substantial losses in greenhouse-grown peppers in southeastern Spain. This study evaluates the use of biodisinfestation (BS) (organic amendment + solarisation) as an alternative to using methyl bromide (MB) over three consecutive years to control the nematode in greenhouse conditions. Brassica carinata (BP) pellets or B. carinata (BP) + fresh sheep manure (M) were evaluated in treatments which began on two different dates (August and October) and the results were compared with MB-disinfested and untreated controls. During the third year, the gall index for BP was lower than that obtained for BP +M and in the August treatment than in the October treatment. The commercial crop of pepper fruit obtained with the biodisinfestation treatments begun in August was similar to or higher than that obtained with MB, and higher than that obtained with both October biodisinfestation treatments. The yield of the October biodisinfestation treatments was higher than that of the untreated one. In August of all the years studied, the accumulated exposure times were greater than the thresholds required to kill M. incognita populations at 15 cm depth. The incidence of the nematode did not correspond to the reduction achieved during solarisation, and seemed to increase during the crop cycle. Further studies should look at why high temperatures do not produce a sustained reduction in the populations of Meloidogyne incognita. (Author) 56 refs.

  1. Evaluation of roselle (Hibiscus sabdariffa) leaf and pomegranate (Punica granatum) fruit rind for activity against Meloidogyne incognita

    Science.gov (United States)

    Pomegranate (Punica granatum) fruit and roselle (Hibiscus sabdariffa) leaves have been used in traditional medicine, including as anthelmintics. Methanolic extracts from these plants were investigated for activity against the southern root-knot nematode (RKN) Meloidogyne incognita. Dried, ground p...

  2. Crop Rotation and Nematicides for Management of Mixed Populations of Meloidogyne spp. on Tobacco.

    Science.gov (United States)

    Fortnum, B A; Lewis, S A; Johnson, A W

    2001-12-01

    The effects of crop rotation and the nematicides 1,3-dichloropropene (1,3-D), ethoprop, and fenamiphos on the relative frequency of Meloidogyne incognita race 3, M. arenaria race 2, and M. javanica and tobacco yields on a sandy loam soil were determined. Cropping sequences altered the species composition and population densities of Meloidogyne spp. Meloidogyne arenaria and M. incognita predominated when cotton, corn, sorghum, or rye-fallow preceded tobacco. Meloidogyne javanica and M. arenaria predominated when tobacco preceded tobacco. Sorghum, cotton, corn, or rye-fallow preceding tobacco enhanced yields compared to tobacco preceding tobacco in plots containing mixtures of Meloidogyne species. Sorghum supported minimal reproduction of any Meloidogyne spp. Application of 1,3-D increased tobacco yields and reduced root galling when compared to untreated controls. Both fenamiphos and ethoprop treatments were less effective than 1,3-D in controlling Meloidogyne spp. or increasing yields. A rotation crop x nematicide interaction was not observed. In continuous tobacco, use of the M. incognita-resistant tobacco cv. Coker 176 increased tobacco yields when compared to the M. incognita-susceptible cv. Coker 319 when 1,3-D was not applied.

  3. Meloidogyne incognita emigration from cotton roots may be induced by the resistance QTL qMi-C11

    Science.gov (United States)

    Upland cotton (Gossypium hirsutum) is one of the most widely grown crops in the southern US, and Meloidogyne incognita is the most significant pathogen of cotton in the US. Two QTLs, qMi-C11 and qMi-C14, conferring resistance to M. incognita have been identified in cotton. Previous research docume...

  4. Bacillus cereus strain S2 shows high nematicidal activity against Meloidogyne incognita by producing sphingosine

    Science.gov (United States)

    Gao, Huijuan; Qi, Gaofu; Yin, Rong; Zhang, Hongchun; Li, Chenggang; Zhao, Xiuyun

    2016-01-01

    Plant-parasitic nematodes cause serious crop losses worldwidely. This study intended to discover the antagonistic mechanism of Bacillus cereus strain S2 against Meloidogyne incognita. Treatment with B. cereus strain S2 resulted in a mortality of 77.89% to Caenorhabditis elegans (a model organism) and 90.96% to M. incognita. In pot experiment, control efficiency of B. cereus S2 culture or supernatants were 81.36% and 67.42% towards M. incognita, respectively. In field experiment, control efficiency was 58.97% towards M. incognita. Nematicidal substances were isolated from culture supernatant of B. cereus S2 by polarity gradient extraction, silica gel column chromatography and HPLC. Two nematicidal compounds were identified as C16 sphingosine and phytosphingosine by LC-MS. The median lethal concentration of sphingosine was determined as 0.64 μg/ml. Sphingosine could obviously inhibit reproduction of C. elegans, with an inhibition rate of 42.72% for 24 h. After treatment with sphingosine, ROS was induced in intestinal tract, and genital area disappeared in nematode. Furthermore, B. cereus S2 could induce systemic resistance in tomato, and enhance activity of defense-related enzymes for biocontrol of M. incognita. This study demonstrates the nematicidal activity of B. cereus and its product sphingosine, as well provides a possibility for biocontrol of M. incognita. PMID:27338781

  5. Identification of Nematicidal Constituents of Notopterygium incisum Rhizomes against Bursaphelenchus xylophilus and Meloidogyne incognita

    OpenAIRE

    Gai Liu; Daowan Lai; Qi Zhi Liu; Ligang Zhou; Zhi Long Liu

    2016-01-01

    During a screening program for new agrochemicals from Chinese medicinal herbs, the ethanol extract of Notopterygium incisum rhizomes was found to possess strong nematicidal activity against the two species of nematodes, Bursaphelenchus xylophilus and Meloidogyne incognita. Based on bioactivity-guided fractionation, the four constituents were isolated from the ethanol extract and identified as columbianetin, falcarindiol, falcarinol, and isoimperatorin. Among the four isolated constituents, tw...

  6. Influence of Soil Temperature on Meloidogyne incognita Resistant and Susceptible Cotton, Gossypium hirsutum

    OpenAIRE

    Carter, William W.

    1982-01-01

    The degree of resistance by a cotton plant to Meloidogyne incognita is affected by soil temperature, particularly in moderately resistant cultivars, The total number of nematodes in the resistant and moderately resistant rools at 35 C was equal to, or greater than, the number in susceptible roots at 20, 25, or 30 C. A shift in numbers to developing and egg-bearing forms of nematodes in the susceptible cultivar as tentperature increased indicates development was affected by temperature rather ...

  7. Infection of Cultured Thin Cell Layer Roots of Lycopersicon esculentum by Meloidogyne incognita

    OpenAIRE

    Radin, D. N.; Eisenback, J. D.

    1991-01-01

    A new aseptic culture system for studying interactions between tomato (Lycopersicon esculentum) and Meloidogyne incognita is described. Epidermal thin cell layer explants from peduncles of tomato produced up to 20 adventitious roots per culture in 4-9 days on Murashige &Scoog medium plus kinetin and indole acetic acid. Rooted cultures were transferred to Gamborg's B-5 medium and inoculated with infective second-stage juveniles. Gall formation was apparent 5 days after inoculation and egg prod...

  8. EFFECT OF ROOT EXUDATES OF TAGETES SP. ON EGG HATCHING BEHAVIOR OF MELOIDOGYNE INCOGNITA

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    Iruthaya Kalaiselvam

    2011-10-01

    Full Text Available The effect root exudates of pre-planted marigold intercropped with tomato in regulating the hatching behavior of root-knot nematode - Meloidogyne incognita eggs were investigated. Marigold cultivars Tagetes patula, T. minuta, T. erecta, T. erecta (var. Orange, T. erecta (var. Yellow significantly reduced the numbers of second-stage juveniles (J2s in subsequent tomato compared to the tomato-tomato control. Four different concentrations (25, 50, 75 and 100 % of water soluble extract from the selected varieties of Marigold cultivars were filtered and added to the petri dish and infested with the eggs of M. incognita. Data indicate that egg hatching was significantly affected by root exudates of Tagetes sp. however, nematicidal activity was species dependent. Root exudates of T. erecta were lethal to J2 of M. incognita and were inhibitory to the hatch of eggs at the concentration of 75 % or higher.

  9. Integrated management of root-knot nematode, Meloidogyne incognita infestation in tomato and grapevine.

    Science.gov (United States)

    Kumari, N Swarna; Sivakumar, C V

    2005-01-01

    An integrated approach with the obligate bacterial parasite, Pasteuria penetrans and nematicides was assessed for the management of the root-knot nematode, Meloidogyne incognita infestation in tomato and grapevine. Seedlings of tomato cv. Co3 were transplanted into pots filled with sterilized soil and inoculated with nematodes (5000 juveniles/pot). The root powder of P. penetrans at 10 mg/pot was applied alone and in combination with carbofuran at 6 mg/pot. Application of P. penetrans along with carbofuran recorded lowest nematode infestation (107 nematodes/200 g soil) compared to control (325 nematodes/200 g soil). The rate of parasitization was 83.1% in the carbofuran and P. penetrans combination treatment as against 61.0% in the P. penetrans treatment only. The plant growth was also higher in the combination treatment compared to all other treatments. A field trial was carried out to assess the efficacy of P. penetrans and nematicides viz., carbofuran and phorate in the management of root-knot nematode, M. incognita infestation of grapevine cv. Muscat Hamburg. A nematode and P. penetrans infested grapevine field was selected and treatments either with carbofuran or phorate at 1 g a.i/vine was given. The observations were recorded at monthly interval. The results showed that the soil nematode population was reduced in nematicide treated plots. Suppression of nematodes was higher under phorate (117 nematodes/200 g soil) than under carbofuran (126.7 nematodes/200 g soil) treatment. The number of juveniles parasitized was also influenced by nematicides and spore load carried/juvenile with phorate being superior and the increase being 17.0 and 29.0% respectively over the control. The results of these experiment confirmed the compatibility of P. penetrans with nematicides and its biological control potential against the root-knot nematode.

  10. The nematicidal effect of some bacterial biofertilizers on Meloidogyne incognita in sandy soil

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    M.E El-Hadad

    2011-03-01

    Full Text Available In a greenhouse experiment, the nematicidal effect of some bacterial biofertilizers including the nitrogen fixing bacteria (NFB Paenibacillus polymyxa (four strains, the phosphate solubilizing bacteria (PSB Bacillus megaterium (three strains and the potassium solubilizing bacteria (KSB B. circulans (three strains were evaluated individually on tomato plants infested with the root-knot nematode Meloidogyne incognita in potted sandy soil. Comparing with the uninoculated nematode-infested control, the inoculation with P. polymyxa NFB7, B. megaterium PSB2 and B. circulans KSB2, increased the counts of total bacteria and total bacterial spores in plants potted soil from 1.2 to 2.6 folds estimated 60 days post-inoculation. Consequently, the inoculation with P. polymyxa NFB7 increased significantly the shoot length (cm, number of leaves / plant, shoot dry weight (g / plant and root dry weight (g / plant by 32.6 %, 30.8 %, 70.3 % and 14.2 %, respectively. Generally, the majority treatments significantly reduced the nematode multiplication which was more obvious after 60 days of inoculation. Among the applied strains, P. polymyxa NFB7, B. megaterium PSB2 and B. circulans KSB2 inoculations resulted in the highest reduction in nematode population comparing with the uninoculated nematode-infested control. They recorded the highest reduction in numbers of hatched juveniles/root by 95.8 %, females/root by 63.75 % and juveniles/1kg soil by 57.8 %. These results indicated that these bacterial biofertilizers are promising double purpose microorganisms for mobilizing of soil nutrients (nitrogen, phosphate and potassium and for the biological control of M. incognita.

  11. Resistance of sweet potato clones to meloidogyne incognita races 1 and 3

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    Jorge Augusto Assis Gomes

    2015-09-01

    Full Text Available The objective of this study was to evaluate sweet potato clones for resistance to root-knot nematode, Meloidogyne incognita races 1 and 3. For each nematode physiological race, a greenhouse experiment was set up in a randomized block experimental design with three replications and six plants per plot. Fifty-eight sweet potato clones from the UFVJM germplasm bank were evaluated, plus five commercial cultivars (Brazlândia Rosada, Brazlândia Branca, Palmas, Princesa and Coquinho, plus the cv. Santa Clara tomato (susceptible to Meloidogyne spp.. Stems were planted in 72-cell expanded polystyrene trays, filled with commercial substrate and inoculated with the pathogen thirty days after planting. Forty-five days after inoculation, the eggs were extracted, counted, and later evaluated. Resistance level classification was performed based on reproduction factor (RF and reproduction index (RI. Among the 63 analyzed clones, a percentage of 78% were classified as resistant to M. incognita race 1.79% to race 3 and 67% showed multiple resistance to both M. incognita races.

  12. Resistance of sweet potato clones to meloidogyne incognita races 1 and 3

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    Jorge Augusto Assis Gomes

    2015-01-01

    Full Text Available The objective of this study was to evaluate sweet potato clones for resistance to root-knot nematode, Meloidogyne incognita races 1 and 3. For each nematode physiological race, a greenhouse experiment was set up in a randomized block experimental design with three replications and six plants per plot. Fifty-eight sweet potato clones from the UFVJM germplasm bank were evaluated, plus five commercial cultivars (Brazlândia Rosada, Brazlândia Branca, Palmas, Princesa and Coquinho, plus the cv. Santa Clara tomato (susceptible to Meloidogyne spp.. Stems were planted in 72-cell expanded polystyrene trays, filled with commercial substrate and inoculated with the pathogen thirty days after planting. Forty-five days after inoculation, the eggs were extracted, counted, and later evaluated. Resistance level classification was performed based on reproduction factor (RF and reproduction index (RI. Among the 63 analyzed clones, a percentage of 78% were classified as resistant to M. incognita race 1.79% to race 3 and 67% showed multiple resistance to both M. incognita races.

  13. Penetration, Post-penetration Development, and Reproduction of Meloidogyne incognita on Cucumis melo var. texanus.

    Science.gov (United States)

    Faske, T R

    2013-03-01

    Cucumis melo var. texanus, a wild melon commonly found in the southern United States and two accessions, Burleson Co. and MX 1230, expressed resistance to Meloidogyne incognita in preliminary experiments. To characterize the mechanism of resistance, we evaluated root penetration, post-penetration development, reproduction, and emigration of M. incognita on these two accessions of C. melo var. texanus. Additionally, we evaluated 22 accessions of C. melo var. texanus for their reaction against M. incognita in a greenhouse experiment. Fewer (P ≤ 0.05) J2 penetrated the root system of C. melo var. texanus accessions (Burleson Co. and MX 1230) and C. metuliferus (PI 482452) (resistant control), 7 days after inoculation (DAI) than in C. melo 'Hales Best Jumbo' (susceptible control). A delayed (P ≤ 0.05) rate of nematode development was observed at 7, 14, and 21 DAI that contributed to lower (P ≤ 0.05) egg production on both accessions and C. metuliferus compared with C. melo. Though J2 emigration was observed on all Cucumis genotypes a higher (P ≤ 0.05) rate of J2 emigration was observed from 3 to 6 DAI on accession Burleson Co. and C. metuliferus than on C. melo. The 22 accessions of C. melo var. texanus varied relative to their reaction to M. incognita with eight supporting similar levels of nematode reproduction to that of C. metuliferus. Cucumis melo var. texanus may be a useful source of resistance against root-knot nematode in melon.

  14. ProteÃÃo de tomateiro a Meloidogyne incognita pelo extrato aquoso de Tagetes patula

    OpenAIRE

    Gilmar Franzener

    2005-01-01

    O objetivo deste trabalho foi avaliar o efeito protetor do extrato aquoso (EA) de Tagetes patula em tomateiro a Meloidogyne incognita. EA de flores, folhas e raÃzes foram obtidos por infusÃo na proporÃÃo de 50 g de material vegetal desidratado em 1000 mL de Ãgua destilada. O EA foi testado in vitro sobre ovos e juvenis de segundo estÃdio (J2) de M. incognita sem diluiÃÃo e diluÃdo 1:1, 1:2, 1:3 e 1:4 (extrato:Ãgua, v/v) e em plantas inoculadas de tomateiro cv. âKadÃâ cultivadas em vasos, sem ...

  15. Direct identification of the Meloidogyne incognita secretome reveals proteins with host cell reprogramming potential.

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    Stéphane Bellafiore

    2008-10-01

    Full Text Available The root knot nematode, Meloidogyne incognita, is an obligate parasite that causes significant damage to a broad range of host plants. Infection is associated with secretion of proteins surrounded by proliferating cells. Many parasites are known to secrete effectors that interfere with plant innate immunity, enabling infection to occur; they can also release pathogen-associated molecular patterns (PAMPs, e.g., flagellin that trigger basal immunity through the nematode stylet into the plant cell. This leads to suppression of innate immunity and reprogramming of plant cells to form a feeding structure containing multinucleate giant cells. Effectors have generally been discovered using genetics or bioinformatics, but M. incognita is non-sexual and its genome sequence has not yet been reported. To partially overcome these limitations, we have used mass spectrometry to directly identify 486 proteins secreted by M. incognita. These proteins contain at least segmental sequence identity to those found in our 3 reference databases (published nematode proteins; unpublished M. incognita ESTs; published plant proteins. Several secreted proteins are homologous to plant proteins, which they may mimic, and they contain domains that suggest known effector functions (e.g., regulating the plant cell cycle or growth. Others have regulatory domains that could reprogram cells. Using in situ hybridization we observed that most secreted proteins were produced by the subventral glands, but we found that phasmids also secreted proteins. We annotated the functions of the secreted proteins and classified them according to roles they may play in the development of root knot disease. Our results show that parasite secretomes can be partially characterized without cognate genomic DNA sequence. We observed that the M. incognita secretome overlaps the reported secretome of mammalian parasitic nematodes (e.g., Brugia malayi, suggesting a common parasitic behavior and a possible

  16. Response of cucurbit rootstocks for grafted melon (Cucumis melo) to southern root-knot nematode, Meloidogyne incognita

    Science.gov (United States)

    Root-knot nematodes (RKN) are an important re-emerging pest of melon (Cucumis melo), due largely to the loss of methyl bromide as a pre-plant soil fumigant. Melon is highly susceptible to southern RKN, Meloidogyne incognita, which causes severe root galling and reduced melon fruit yields. Cucurbit...

  17. Studies on the interactions of Meloidogyne incognita, Radopholus similis and Fusarium solani on black pepper (Piper nigrum L.).

    NARCIS (Netherlands)

    Mustika, I.

    1990-01-01

    This study on the interactions between various cultivars of the black pepper plant (Piper nigrum L. ) and three of its pathogens, Meloidogyne Incognita (Kofoid & White) , Radopholus similis (Cobb) , Thorne and Fusarium solani f. sp. piperi Albuquerque was initiated to search for a biological cause o

  18. Resistance to Southern Root-knot Nematode (Meloidogyne incognita) in Wild Watermelon (Citrullus lanatus var. citroides)

    Science.gov (United States)

    Thies, Judy A.; Ariss, Jennifer J.; Kousik, Chandrasekar S.; Hassell, Richard L.; Levi, Amnon

    2016-01-01

    Southern root-knot nematode (RKN, Meloidogyne incognita) is a serious pest of cultivated watermelon (Citrullus lanatus var. lanatus) in southern regions of the United States and no resistance is known to exist in commercial watermelon cultivars. Wild watermelon relatives (Citrullus lanatus var. citroides) have been shown in greenhouse studies to possess varying degrees of resistance to RKN species. Experiments were conducted over 2 yr to assess resistance of southern RKN in C. lanatus var. citroides accessions from the U.S. Watermelon Plant Introduction Collection in an artificially infested field site at the U.S. Vegetable Laboratory in Charleston, SC. In the first study (2006), 19 accessions of C. lanatus var. citroides were compared with reference entries of Citrullus colocynthis and C. lanatus var. lanatus. Of the wild watermelon accessions, two entries exhibited significantly less galling than all other entries. Five of the best performing C. lanatus var. citroides accessions were evaluated with and without nematicide at the same field site in 2007. Citrullus lanatus var. citroides accessions performed better than C. lanatus var. lanatus and C. colocynthis. Overall, most entries of C. lanatus var. citroides performed similarly with and without nematicide treatment in regard to root galling, visible egg masses, vine vigor, and root mass. In both years of field evaluations, most C. lanatus var. citroides accessions showed lesser degrees of nematode reproduction and higher vigor and root mass than C. colocynthis and C. lanatus var. lanatus. The results of these two field evaluations suggest that wild watermelon populations may be useful sources of resistance to southern RKN. PMID:27168648

  19. Evaluation of Several Approaches to Manage Meloidogyne incognita and Cotton Seedling Disease Complexes in the High Plains of Texas.

    Science.gov (United States)

    Fichtner, S M; Isakeit, T; Wheeler, T A; Kaufman, H W; Gannaway, J R

    2005-03-01

    Field experiments were conducted for control of the southern root-knot nematode (Meloidogyne incognita) and cotton seedling disease fungi (primarily Thielaviopsis basicola) in one naturally infested field during 1999 and 2000 and in three additional fields in 2000. Treatments included: seed-applied fungicides (triadimenol + mefenoxam + thiram and carboxin + PCNB + mefenoxam), cultivars (Paymaster [PM] 2326 RR and PM 2200 RR), and a nematicide (aldicarb at 0.83 kg a.i/ha). Plant stands were higher (P = 0.02) in the presence of aldicarb (77% emergence) than in its absence (74% emergence). Hypocotyl disease symptom ratings were lower (P = 0.0001) following triadimenol + mefenoxam + thiram seed treatment (0.53) as compared with carboxin + PCNB + mefenoxam (0.93). Root necrosis was lower (P = 0.002) following triadimenol + mefenoxam + thiram seed treatment (27%) as compared with carboxin + PCNB + mefenoxam (34%). In one field, in both years, aldicarb was associated with more root necrosis (58%) than in its absence (46%) (P = 0.004). At three other sites aldicarb did not affect root necrosis. Population densities of Meloidogyne incognita eggs and juveniles at midseason were greater (P = 0.005, P = 0.003, respectively) on PM 2200 RR (less resistant) than on PM 2326 RR (more resistant). Yield was affected by the plant genotype by aldicarb interaction (P = 0.02) but not by seed treatments. Aldicarb effect on yield was dependent on cultivar, whereas affect of seed treatment on root health was consistent and independent of cultivar and aldicarb. No conditions were identified when use of triadimenol + mefenoxam was detrimental.

  20. Dose assessment of HeberNem to control of Meloidogyne incognita Chitwood in greenhouses

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    Mario Fleitas Díaz

    2016-02-01

    Full Text Available In the houses of protected crops Agricultural Company República Dominicana, Carlos Manuel de Céspedes municipality, Camagüey, an experiment was developed to evaluate different doses of bionematicide HeberNem in controlling the nematode Meloidogyne incognita Chitwood and his participation in the growth and development of the tomato (Solanum lycopersicum crop, the experimental design was in randomized blocks, the test was composed of 8 treatments replicated twice, evaluating a total of 40 plants for each treatment which were measured: plant height, stem diameter the number of leaflets, the number of clusters per plant, number of flowers per cluster and number of fruits per bunch, they were made weekly. Also at the end of the campaign took root degree determined according to the scale indicated by Zeck, (1971. Data were analyzed using analysis of variance and determined the levels of statistical significance at 5%, by dócima Tukey multiple range. We found an inverse relationship between the parameters of growth and development weighed against the presence of M. incognita Chitwood. At doses of 8 l / ha, 12 l / ha and 16 l / ha were achieved better results in controlling the nematode M. incognita Chitwood.

  1. Chemical Composition and Nematicidal Activity of Essential Oil of Agastache rugosa against Meloidogyne incognita

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    Zhi Wei Deng

    2013-04-01

    Full Text Available The aim of this research was to determine the chemical composition and nematicidal activity of essential oil of Agastache rugosa flowering aerial parts against the root knot nematode, Meloidogyne incognita, and to isolate and identify any nematicidal constituents from the essential oil. The essential oil of A. rugosa aerial parts was obtained by hydrodistillation and analyzed by GC-FID and GC-MS. A total of 37 components of the essential oil were identified, with the principal compounds being methyleugenol (50.51%, estragole (8.55%, and eugenol (7.54%, followed by thymol (3.62%, pulegone (2.56%, limonene (2.49% and caryophyllene (2.38%. Based on bioactivity-guided fractionation, the three active constituents were isolated from the essential oil and identified as methyleugenol, estragole and eugenol. The essential oil of A. rugosa exhibited strong nematicidal activity against M. incognita, with a LC50 value of 47.3 μg/mL. The components eugenol (LC50 = 66.6 μg/mL and methyleugenol (LC50 = 89.4 μg/mL exhibited stronger nematicidal activity against M. incognita (LC50 = 185.9 μg/mL. The results indicate that the essential oil of A. rugosa aerial parts and its constituent compounds have potential for development into natural nematicides for control of the root knot nematode.

  2. Differential expression of antioxidant enzymes and PR-proteins in compatible and incompatible interactions of cowpea (Vigna unguiculata) and the root-knot nematode Meloidogyne incognita.

    Science.gov (United States)

    Oliveira, J T A; Andrade, N C; Martins-Miranda, A S; Soares, A A; Gondim, D M F; Araújo-Filho, J H; Freire-Filho, F R; Vasconcelos, I M

    2012-02-01

    This study aimed to evaluated the resistance and susceptibility of 10 cowpea cultivars to Meloidogyne incognita in field studies and to analyze the kinetics of the enzymes superoxide dismutase, catalase, peroxidase, chitinase, β-1,3-glucanases and cystein proteinase inhibitors in the root system of two contrasting cowpea cultivars after inoculation with M. incognita. The cultivars CE-31 and Frade Preto were highly resistant; CE-28, CE-01, CE-315, CE-237, were very resistant; CE-70 and CE-216 were moderately resistant, whereas Vita-3 and CE-109 were slightly resistant. In the roots of the highly resistant cultivar CE-31 the activity of the antioxidant enzyme superoxide dismutase increased and catalase decreased and those of the pathogenesis-related proteins chitinase, β-1,3-glucanase, peroxidase and cystein proteinase inhibitor increased in comparison with the root system of the slightly resistant CE-109, during the course of M. incognita infestation. Thus the changes in the activities of these enzymes might be related to the smaller final population of M. incognita in CE-31 and may contribute to the high resistance of this cowpea cultivar against infection and colonization by this nematode species.

  3. Influence of Soil Temperature on Meloidogyne incognita Resistant and Susceptible Cotton, Gossypium hirsutum.

    Science.gov (United States)

    Carter, W W

    1982-07-01

    The degree of resistance by a cotton plant to Meloidogyne incognita is affected by soil temperature, particularly in moderately resistant cultivars, The total number of nematodes in the resistant and moderately resistant rools at 35 C was equal to, or greater than, the number in susceptible roots at 20, 25, or 30 C. A shift in numbers to developing and egg-bearing forms of nematodes in the susceptible cultivar as tentperature increased indicates development was affected by temperature rather than by genetic resistance mechanisms. However, the nematode resistant cultivar did not support maturation of nematodes until a soil tempurature of 35 C was attained. This indicated that resistance mechanisms are partially repressed at 35 C and differences in nematode development cannot be explained in terms of accumulated heat units. The moderately resistant cultivar was significantly more sensitive to the effects of high temperature than was the resistant cultivar.

  4. Infection of Cultured Thin Cell Layer Roots of Lycopersicon esculentum by Meloidogyne incognita.

    Science.gov (United States)

    Radin, D N; Eisenback, J D

    1991-10-01

    A new aseptic culture system for studying interactions between tomato (Lycopersicon esculentum) and Meloidogyne incognita is described. Epidermal thin cell layer explants from peduncles of tomato produced up to 20 adventitious roots per culture in 4-9 days on Murashige &Scoog medium plus kinetin and indole acetic acid. Rooted cultures were transferred to Gamborg's B-5 medium and inoculated with infective second-stage juveniles. Gall formation was apparent 5 days after inoculation and egg production by mature females occurred within 25 days at 25 C in the susceptible genotypes Rutgers and Red Alert. Resistant genotypes LA655, LA656, and LA1022 exhibited a characteristic hypersensitive response. This system provides large numbers of cultured root tips for studies on the molecular basis of the host-parasite relationship.

  5. Transcriptome analysis of resistant and susceptible alfalfa cultivars infected with root-knot nematode Meloidogyne incognita.

    Science.gov (United States)

    Postnikova, Olga A; Hult, Maria; Shao, Jonathan; Skantar, Andrea; Nemchinov, Lev G

    2015-01-01

    Nematodes are one of the major limiting factors in alfalfa production. Root-knot nematodes (RKN, Meloidogyne spp.) are widely distributed and economically important sedentary endoparasites of agricultural crops and they may inflict significant damage to alfalfa fields. As of today, no studies have been published on global gene expression profiling in alfalfa infected with RKN or any other plant parasitic nematode. Very little information is available about molecular mechanisms that contribute to pathogenesis and defense responses in alfalfa against these pests and specifically against RKN. In this work, we performed root transcriptome analysis of resistant (cv. Moapa 69) and susceptible (cv. Lahontan) alfalfa cultivars infected with RKN Meloidogyne incognita, widespread root-knot nematode species and a major pest worldwide. A total of 1,701,622,580 pair-end reads were generated on an Illumina Hi-Seq 2000 platform from the roots of both cultivars and assembled into 45,595 and 47,590 transcripts in cvs Moapa 69 and Lahontan, respectively. Bioinformatic analysis revealed a number of common and unique genes that were differentially expressed in susceptible and resistant lines as a result of nematode infection. Although the susceptible cultivar showed a more pronounced defense response to the infection, feeding sites were successfully established in its roots. Characteristically, basal gene expression levels under normal conditions differed between the two cultivars as well, which may confer advantage to one of the genotypes toward resistance to nematodes. Differentially expressed genes were subsequently assigned to known Gene Ontology categories to predict their functional roles and associated biological processes. Real-time PCR validated expression changes in genes arbitrarily selected for experimental confirmation. Candidate genes that contribute to protection against M. incognita in alfalfa were proposed and alfalfa-nematode interactions with respect to resistance

  6. Transcriptome analysis of resistant and susceptible alfalfa cultivars infected with root-knot nematode Meloidogyne incognita.

    Directory of Open Access Journals (Sweden)

    Olga A Postnikova

    Full Text Available Nematodes are one of the major limiting factors in alfalfa production. Root-knot nematodes (RKN, Meloidogyne spp. are widely distributed and economically important sedentary endoparasites of agricultural crops and they may inflict significant damage to alfalfa fields. As of today, no studies have been published on global gene expression profiling in alfalfa infected with RKN or any other plant parasitic nematode. Very little information is available about molecular mechanisms that contribute to pathogenesis and defense responses in alfalfa against these pests and specifically against RKN. In this work, we performed root transcriptome analysis of resistant (cv. Moapa 69 and susceptible (cv. Lahontan alfalfa cultivars infected with RKN Meloidogyne incognita, widespread root-knot nematode species and a major pest worldwide. A total of 1,701,622,580 pair-end reads were generated on an Illumina Hi-Seq 2000 platform from the roots of both cultivars and assembled into 45,595 and 47,590 transcripts in cvs Moapa 69 and Lahontan, respectively. Bioinformatic analysis revealed a number of common and unique genes that were differentially expressed in susceptible and resistant lines as a result of nematode infection. Although the susceptible cultivar showed a more pronounced defense response to the infection, feeding sites were successfully established in its roots. Characteristically, basal gene expression levels under normal conditions differed between the two cultivars as well, which may confer advantage to one of the genotypes toward resistance to nematodes. Differentially expressed genes were subsequently assigned to known Gene Ontology categories to predict their functional roles and associated biological processes. Real-time PCR validated expression changes in genes arbitrarily selected for experimental confirmation. Candidate genes that contribute to protection against M. incognita in alfalfa were proposed and alfalfa-nematode interactions with

  7. Resistance induction for Meloidogyne incognita in sugarcane through mineral organic fertilizers

    Directory of Open Access Journals (Sweden)

    Andréa Chaves

    2009-12-01

    Full Text Available The effects of Coda Radimax (CR, Coda Humus-PK (CH and Coda Vit (CV on the induction of resistance for Meloidogyne incognita in sugarcane (Saccharum sp. varieties (RB92579, RB863129, RB867515 through nematode reproduction, plant development and root anatomy analysis, emphasizing the differences of the lignin deposition, and cortex-vascular cylinder proportions were investigated. In 90 days after inoculation with eggs of M. incognita, CR reduced the number of eggs per root system in all the sugarcane varieties; CH and CV reduced eggs density in RB867515; CR increased stalk number in RB92579 and fresh weight of shoots in RB863129 and RB92579; CH increased plant height in RB92579 and fresh weight of shoots in RB92579 and RB867515, CV affected fresh weigh of shoots and roots of RB863129. All the tested compounds did not affect stalk diameter, number and dry weight of shoots. Cross-sections of roots showed no anatomical changes in the M. incognita inoculated tissues.Este estudo investigou, em condições de casa de vegetação, os efeitos de três complexos organo-minerais (Coda Radimax, Coda Humus-PK e Coda Vit na indução de resistência a Meloidogyne incognita em três variedades: RB92579, RB863129, RB867515 de cana-de-açúcar (Saccharum sp., considerando-se a reprodução do nematóide, desenvolvimento das plantas e anatomia das raízes, com ênfase a diferenças na deposição de lignina e proporções do córtex e cilindro vascular. As avaliações foram efetuadas 90 dias após a inoculação com 5000 ovos de M. incognita por planta. Em relação à testemunha, Coda Radimax reduziu significativamente o número final de ovos por sistema radicular em todas as variedades. Coda Humus-PK e Coda Vit se mostraram eficientes em diminuir a densidade de ovos em RB867515, mas não em RB863129. Todos os compostos testados não afetaram o diâmetro do colmo, peso da biomassa seca da parte aérea e número de perfilho. Coda Radimax aumentou

  8. Identification of Nematicidal Constituents of Notopterygium incisum Rhizomes against Bursaphelenchus xylophilus and Meloidogyne incognita

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    Gai Liu

    2016-09-01

    Full Text Available During a screening program for new agrochemicals from Chinese medicinal herbs, the ethanol extract of Notopterygium incisum rhizomes was found to possess strong nematicidal activity against the two species of nematodes, Bursaphelenchus xylophilus and Meloidogyne incognita. Based on bioactivity-guided fractionation, the four constituents were isolated from the ethanol extract and identified as columbianetin, falcarindiol, falcarinol, and isoimperatorin. Among the four isolated constituents, two acetylenic compounds, falcarindiol and falcarinol (2.20–12.60 μg/mL and 1.06–4.96 μg/mL, respectively exhibited stronger nematicidal activity than two furanocoumarins, columbianetin, and isoimperatorin (21.83–103.44 μg/mL and 17.21–30.91 μg/mL, respectively against the two species of nematodes, B. xylophilus and M. incognita. The four isolated constituents also displayed phototoxic activity against the nematodes. The results indicate that the ethanol extract of N. incisum and its four isolated constituents have potential for development into natural nematicides for control of plant-parasitic nematodes.

  9. Identification of Nematicidal Constituents of Notopterygium incisum Rhizomes against Bursaphelenchus xylophilus and Meloidogyne incognita.

    Science.gov (United States)

    Liu, Gai; Lai, Daowan; Liu, Qi Zhi; Zhou, Ligang; Liu, Zhi Long

    2016-09-23

    During a screening program for new agrochemicals from Chinese medicinal herbs, the ethanol extract of Notopterygium incisum rhizomes was found to possess strong nematicidal activity against the two species of nematodes, Bursaphelenchus xylophilus and Meloidogyne incognita. Based on bioactivity-guided fractionation, the four constituents were isolated from the ethanol extract and identified as columbianetin, falcarindiol, falcarinol, and isoimperatorin. Among the four isolated constituents, two acetylenic compounds, falcarindiol and falcarinol (2.20-12.60 μg/mL and 1.06-4.96 μg/mL, respectively) exhibited stronger nematicidal activity than two furanocoumarins, columbianetin, and isoimperatorin (21.83-103.44 μg/mL and 17.21-30.91 μg/mL, respectively) against the two species of nematodes, B. xylophilus and M. incognita. The four isolated constituents also displayed phototoxic activity against the nematodes. The results indicate that the ethanol extract of N. incisum and its four isolated constituents have potential for development into natural nematicides for control of plant-parasitic nematodes.

  10. Evaluation of Animal Dungs and Organomineral Fertilizer for the Control of Meloidogyne incognita on Sweet Potato

    Directory of Open Access Journals (Sweden)

    Oluremi Solomon Osunlola

    2015-01-01

    Full Text Available Root-knot nematode, Meloidogyne incognita, is an important animate pathogen causing major damage and severe reductions in the growth, yield, and quality of sweet potato. Nematicides are expensive and their application also causes environmental pollution. A field experiment was therefore conducted to evaluate the effectiveness of poultry dung (10 or 20 t/ha, cow dung (10 or 20 t/ha, horse dung (10 or 20 t/ha, goat dung (10 or 20 t/ha, organomineral fertilizer (2 or 4 t/ha, and carbofuran (3 kg a.i/ha in the management of M. incognita on sweet potato using a randomized complete block design. The unamended plots served as control. Data were analysed using ANOVA (p≤0.05. All organic materials and carbofuran significantly (p≤0.05 reduced nematode reproduction and root damage compared with control. Poultry dung (10 and 20 t/ha and carbofuran were, however, more efficient in nematode control than other organic materials. Sweet potato plants that were grown on soil treated with organomineral fertilizer had the highest mean number of vines and fresh shoot weight, while poultry dung improved sweet potato quality and yield. It is therefore recommended that the use of poultry dung be employed in combination with other nematode control strategies to achieve sustainable, economic, and environment-friendly nematode management.

  11. Effects of Nematicides and Herbicides Alone or Combined on Meloidogyne incognita Egg Hatch and Development.

    Science.gov (United States)

    Payan, L A; Johnson, A W; Littrell, R H

    1987-10-01

    The effects of nematicides carbofuran (C) and fenamiphos (F) and herbicides metribuzin (M) and trifluralin (T), alone and in combination, on hatching, penetration, development, and reproduction of Meloidogyne incognita race 3 were determined under laboratory conditions. To study hatching, entire egg masses were exposed to nematicides (6 mug/ml), herbicides (0.5 mug/ml), and their combinations over a period of 16 days; the hatched juveniles were extracted and counted every 48 hours. Second-stage juveniles that hatched from day 6 to day 8 were used as inoculum to determine the effects of the chemicals on penetration, development, and reproduction of M. incognita on tomato 4, 16, and 32 days after inoculation. F, F + T, and F + M inhibited hatching; whereas, C, T, M, C + T, and C + M did not affect hatching, penetration, development of females, or reproduction. Since so few juveniles hatched from the fenamiphos treatments, we were not able to use them for the postinfection development study. There was no apparent reduction in the effect of the nematicides by the herbicides.

  12. Mutations in Acetylcholinesterase2 (ace2) increase the insensitivity of acetylcholinesterase to fosthiazate in the root-knot nematode Meloidogyne incognita.

    Science.gov (United States)

    Huang, Wen-Kun; Wu, Qin-Song; Peng, Huan; Kong, Ling-An; Liu, Shi-Ming; Yin, Hua-Qun; Cui, Ru-Qiang; Zhan, Li-Ping; Cui, Jiang-Kuan; Peng, De-Liang

    2016-11-29

    The root-knot nematode Meloidogyne incognita causes severe damage to continuously cropping vegetables. The control of this nematode relies heavily on organophosphate nematicides in China. Here, we described resistance to the organophosphate nematicide fosthiazate in a greenhouse-collected resistant population (RP) and a laboratory susceptible population (SP) of M. incognita. Fosthiazate was 2.74-fold less toxic to nematodes from RP than that from SP. Quantitative real-time PCR revealed that the acetylcholinesterase2 (ace2) transcription level in the RP was significantly higher than that in the SP. Eighteen nonsynonymous amino acid differences in ace2 were observed between the cDNA fragments of the RP and SP. The acetylcholinesterase (AChE) protein activity in the RP was significantly reduced compared with that in the SP. After knocking down the ace2 gene, the ace2 transcription level was significantly decreased, but no negative impact on the infection of juveniles was observed. The 50% lethal concentration of the RNAi RP population decreased 40%, but the inhibition rate of fosthiazate against AChE activity was significantly increased in RP population. Thus, the increased fosthiazate insensitivity in the M. incognita resistant population was strongly associated with mutations in ace2. These results provide valuable insights into the resistance mechanism of root-knot nematode to organophosphate nematicides.

  13. Acetic Acid, 2-Undecanone, and (E)-2-Decenal Ultrastructural Malformations on Meloidogyne incognita

    Science.gov (United States)

    Ntalli, Nikoletta; Ratajczak, Marlena; Oplos, Chrisostomos; Menkissoglu-Spiroudi, Urania; Adamski, Zbigniew

    2016-01-01

    The use of natural compounds to control phytonematodes is significantly increasing, as most of the old synthetic pesticides have been banned due to their eco-hostile character. Plant secondary metabolites are now evaluated as biologically active molecules against Meloidogyne spp. but their target site in the nematode body is rarely specified. Herein, we report on the ultrastructure modifications of the Meloidogyne incognita J2 after treatment with nematicidal plant secondary metabolites, that is acetic acid, (E)-2-decenal, and 2-undecanone. The commercial nematicide fosthiazate acting on acetylcholinesterase was used as control. For this reason, scanning electron microscopy and transmission electron microscopy have been employed. The acetic acid mainly harmed the cuticle, degenerated the nuclei of pseudocoel cells, and vacuolised the cytoplasm. The (E)-2-decenal and 2-undecanone did neither harm to the cuticle nor the somatic muscles but they degenerated the pseudocoel cells. (E)-2-decenal caused malformation of somatic muscles. According to the above, the nematicidal compounds seem to enter the nematode body principally via the digestive system rather than the cuticle, since the main part of the damage is internal. PMID:28154431

  14. SCAR Molecular Markers Correlated with Populations of Meloidogyne incognita Virulent to Resistance Gene Me3%对辣椒抗性基因Me3表现毒性的南方根结线虫群体的SCAR分子标记

    Institute of Scientific and Technical Information of China (English)

    王刚; 李二峰; 茆振川; 谢丙炎; 冯东昕

    2013-01-01

    [Objective] Molecular markers of virulent populations against Me3 in Meloidogyne incognita was studied in order to detect the virulence mutation rapidly and effectively.[Method] Root-knot nematode populations including avirulent population,populations overcoming resistant gene Me3 and the mixed group of the two population were used as experiment materials,polymerase chain reaction was done with 100 primer pairs designed according to M.incognita genome and 19 pairs reported in literature to screen specific band among three populations.And subsequently SCAR primers were designed and a multiplex PCR reaction system was built.[Result] Seven primer pairs amplifying stability bands were screened,two of which were converted into SCAR markers differentiating the three populations.Multiplex PCR from avirulent population and Me3-virulent isolates generated a fragment of 999 and 629 bp,respectively,while from the mixed group generated both of the above fragments.[Conclusion] Virulent mutation markers were successfully developed in M.incognita,and one-step multiplex PCR can be used for identification of Me3-virulence.%[目的]研究南方根结线虫(Meloidogyne incognita)Me3毒性变异群体的分子标记,用快速有效的分子方法来鉴定毒性变异的发生.[方法]以南方根结线虫的无毒群体以及抗性基因Me3毒性群体为材料,用根据南方根结线虫基因组设计的100对引物和19对来自文献的引物进行扩增,筛选出在3个种群中扩增的差异条带,设计SCAR引物,并建立多重PCR反应体系.[结果]得到了7对能在3个群体稳定扩增出差异条带的多态性引物,把其中的2个位点开发为SCAR标记,能够区分开3个线虫群体.多重PCR反应体系在无毒群体和Me3毒性群体中分别扩增出1条999 bp和1条629 bp的条带,在混合群体扩增出999和629bp的2条带.[结论]成功开发了对Me3表现毒性的南方根结线虫变异群体的分子标记,可用多重PCR体系一次性鉴定Me3毒性变异的发生.

  15. Nematicidal activity of fervenulin isolated from a nematicidal actinomycete, Streptomyces sp. CMU-MH021, on Meloidogyne incognita.

    Science.gov (United States)

    Ruanpanun, Pornthip; Laatsch, Hartmut; Tangchitsomkid, Nuchanart; Lumyong, Saisamorn

    2011-06-01

    An isolate of the actinomycete, Streptomyces sp. CMU-MH021 produced secondary metabolites that inhibited egg hatch and increased juvenile mortality of the root-knot nematode Meloidogyne incognita in vitro. 16S rDNA gene sequencing showed that the isolate sequence was 99% identical to Streptomyces roseoverticillatus. The culture filtrates form different culture media were tested for nematocidal activity. The maximal activity against M. incognita was obtained by using modified basal (MB) medium. The nematicidal assay-directed fractionation of the culture broth delivered fervenulin (1) and isocoumarin (2). Fervenulin, a low molecular weight compound, shows a broad range of biological activities. However, nematicidal activity of fervenulin was not previously reported. The nematicidal activity of fervenulin (1) was assessed using the broth microdilution technique. The lowest minimum inhibitory concentrations (MICs) of the compound against egg hatch of M. incognita was 30 μg/ml and juvenile mortality of M. incognita increasing was observed at 120 μg/ml. Moreover, at the concentration of 250 μg/ml fervenulin (1) showed killing effect on second-stage nematode juveniles of M. incognita up to 100% after incubation for 96 h. Isocoumarin (2), another bioactive compound produced by Streptomyces sp. CMU-MH021, showed weak nematicidal activity with M. incognita.

  16. REPRODUÇÃO DE Meloidogyne incognita RAÇA 2 E DE Meloidogyne javanica EM OITO ESPÉCIES DE PLANTAS MEDICINAIS

    Directory of Open Access Journals (Sweden)

    S.L. MACIEL

    1996-05-01

    Full Text Available Avaliaram-se as taxas reprodutivas de Meloidogyne incognita raça 2 e de Meloidogyne javanica em oito espécies de plantas consideradas medicinais, em vasos com 500 ml de solo, sob condição de casa de vegetação. Cada planta foi inoculada com 5000 ovos, em média, estabelecendo-se cinco repetições. Realizaram-se as avaliações após 45 a 55 dias das inoculações, com base nos índices de massas de ovos e nos fatores de reprodução dos nematóides. Achillea millefolium (mil-folhas, Arctium lappa (bardana, Bryophyllum calycinum (folha-da-fortuna e Crassula portulacea (bálsamo foram hospedeiras não eficientes ou desfavoráveis a ambas as espécies. Plectranthus barbatus (boldo e Polygonum hidropiperoides (polígono foram eficientes à reprodução das duas espécies. Achyrocline satureoides (macela e Tropaeolum majus (chagas foram eficientes para M. javanica e não para M. incognita.The reproductive rates of the root-knot nematodes Meloidogyne incognita race 2 and M. javanica in the roots of eight medicinal plant species were assessed under greenhouse condition. Each plant, growing in a pot containing 500 ml of sterilized soil, was inoculated with an average number of 5,000 eggs, with five repetitions. Egg mass index and reproduction factor data were used for the evaluation, 45-55 days after plant inoculation. Achillea millefolium, Arctium lappa, Bryophyllum calycinum, and Crassula portulacea were rated as poor or nonefficient hosts, while Plectranthus barbatus and Polygonum hidropiperoides were efficient for both nematode species. Achyrocline satureoides and Tropaeolum majus were efficient for M. javanica, but nonefficient for M. incognita.

  17. Nematicidal Activity of trans-2-Hexenal against Southern Root-Knot Nematode (Meloidogyne incognita) on Tomato Plants.

    Science.gov (United States)

    Lu, Hongbao; Xu, Shuangyu; Zhang, Wenjuan; Xu, Chunmei; Li, Beixing; Zhang, Daxia; Mu, Wei; Liu, Feng

    2017-01-25

    Botanical nematicides have recently received increasing interest because of the high risks of some traditional nematicides to human health and the environment. This study evaluated the nematicidal activity of a plant volatile, trans-2-hexenal, against Meloidogyne incognita. This compound exhibited higher activity in a fumigation experiment than in the aqueous phase in vitro. Both in pot tests and in field trials, trans-2-hexenal showed significant efficacy against M. incognita while maintaining excellent plant growth, especially at doses of 1000 and 500 L ha(-1), which were superior to that of abamectin at 180 g ha(-1) via hole application treatment but not significantly different from fumigation with 400 kg ha(-1) of dazomet. Furthermore, plants treated with 500 L ha(-1) trans-2-hexenal had fruit yields 20.2 and 45% greater than the control group. On this basis, trans-2-hexenal may be a potential alternative fumigation agent for controlling M. incognita on tomato crops.

  18. Efeito de extratos aquosos de espécies de Asteraceae sobre Meloidogyne incognita Effect of aqueous extracts of Asteraceae species on Meloidogyne incognita

    Directory of Open Access Journals (Sweden)

    Isabel Cristina Madeira Ferreira

    2013-03-01

    Full Text Available Estudou-se, in vitro e in vivo a atividade nematicida dos extratos aquosos de vedélia (Sphagneticola trilobata, erva-de-touro (Tridax procumbens, cravo-de-defunto (Tagetes patula, girassol mexicano (Tithonia diversifolia, botão de ouro (Unxia suffruticosa e zínia (Zinnia peruviana, sobre Meloidogyne incognita. Os extratos foram preparados na proporção de 1,0g do material seco e triturado para 10mL de água destilada e armazenados por 24h, sendo seguidamente utilizados nos experimentos. Nos testes in vitro, foram depositados 4,0mL do extrato bruto e 2,0mL de uma suspensão aquosa contendo 200 ovos do nematóide em placas de Petri de 5cm de diâmetro e, quinze dias após, procedeu-se a contagem do número de juvenis eclodidos e dos ovos remanescentes para o cálculo das porcentagens de eclosão. Nos testes in vivo, os extratos foram aplicados, separadamente, via pulverização foliar, tratamento de raiz e vertido no solo, semanalmente durante 60 dias. Como testemunha utilizou-se apenas água nos dois experimentos. No ensaio in vitro observou-se que todos os extratos foram eficientes na redução da eclosão de juvenis de M. incognita quando comparados à testemunha, as porcentagens de redução foram 89,96%, 91,13%, 92,48%, 92,72%, 93,2% e 97,48% para erva-de-touro, cravo-de-defunto, girassol mexicano, vedélia, botão de ouro e zínia, respectivamente, e no ensaio in vivo, que os tratamentos não exerceram nenhum efeito sobre o peso do sistema radicular dos tomateiros, no entanto, observou-se que os resultados diferiram entre as espécies utilizadas e a forma de aplicação do extrato na avaliação do peso fresco da parte aérea das plantas. Quanto ao fator de reprodução, observou-se que nenhum dos extratos apresentou diferença estatística em relação à testemunha, no entanto, quando se compara as diferentes formas de aplicação dos mesmos, observa-se que houve diferença estatística quando os extratos de erva de touro e girassol

  19. Biological Control of Meloidogyne incognita by Aspergillus niger F22 Producing Oxalic Acid

    Science.gov (United States)

    Jang, Ja Yeong; Choi, Yong Ho; Shin, Teak Soo; Kim, Tae Hoon; Shin, Kee-Sun; Park, Hae Woong; Kim, Young Ho; Kim, Hun; Choi, Gyung Ja; Jang, Kyoung Soo; Cha, Byeongjin; Kim, In Seon; Myung, Eul Jae

    2016-01-01

    Restricted usage of chemical nematicides has led to development of environmentally safe alternatives. A culture filtrate of Aspergillus niger F22 was highly active against Meloidogyne incognita with marked mortality of second-stage juveniles (J2s) and inhibition of egg hatching. The nematicidal component was identified as oxalic acid by organic acid analysis and gas chromatography-mass spectroscopy (GC-MS). Exposure to 2 mmol/L oxalic acid resulted in 100% juvenile mortality at 1 day after treatment and suppressed egg hatching by 95.6% at 7 days after treatment. Oxalic acid showed similar nematicidal activity against M. hapla, but was not highly toxic to Bursaphelenchus xylophilus. The fungus was incubated on solid medium and dried culture was used for preparation of a wettable powder-type (WP) formulation as an active ingredient. Two WP formulations, F22-WP10 (ai 10%) and oxalic acid-WP8 (ai 8%), were prepared using F22 solid culture and oxalic acid. In a field naturally infested with M. incognita, application of a mixture of F22-WP10 + oxalic acid-WP8 at 1,000- and 500-fold dilutions significantly reduced gall formation on the roots of watermelon plants by 58.8 and 70.7%, respectively, compared to the non-treated control. The disease control efficacy of the mixture of F22-WP10 + oxalic acid-WP8 was significantly higher than that of a chemical nematicide, Sunchungtan (ai 30% fosthiazate). These results suggest that A. niger F22 can be used as a microbial nematicide for the control of root-knot nematode disease. PMID:27258452

  20. Biological Control of Meloidogyne incognita by Aspergillus niger F22 Producing Oxalic Acid.

    Directory of Open Access Journals (Sweden)

    Ja Yeong Jang

    Full Text Available Restricted usage of chemical nematicides has led to development of environmentally safe alternatives. A culture filtrate of Aspergillus niger F22 was highly active against Meloidogyne incognita with marked mortality of second-stage juveniles (J2s and inhibition of egg hatching. The nematicidal component was identified as oxalic acid by organic acid analysis and gas chromatography-mass spectroscopy (GC-MS. Exposure to 2 mmol/L oxalic acid resulted in 100% juvenile mortality at 1 day after treatment and suppressed egg hatching by 95.6% at 7 days after treatment. Oxalic acid showed similar nematicidal activity against M. hapla, but was not highly toxic to Bursaphelenchus xylophilus. The fungus was incubated on solid medium and dried culture was used for preparation of a wettable powder-type (WP formulation as an active ingredient. Two WP formulations, F22-WP10 (ai 10% and oxalic acid-WP8 (ai 8%, were prepared using F22 solid culture and oxalic acid. In a field naturally infested with M. incognita, application of a mixture of F22-WP10 + oxalic acid-WP8 at 1,000- and 500-fold dilutions significantly reduced gall formation on the roots of watermelon plants by 58.8 and 70.7%, respectively, compared to the non-treated control. The disease control efficacy of the mixture of F22-WP10 + oxalic acid-WP8 was significantly higher than that of a chemical nematicide, Sunchungtan (ai 30% fosthiazate. These results suggest that A. niger F22 can be used as a microbial nematicide for the control of root-knot nematode disease.

  1. Mitochondrial genomes of Meloidogyne chitwoodi and M. incognita (Nematoda: Tylenchina): comparative analysis, gene order and phylogenetic relationships with other nematodes.

    Science.gov (United States)

    Humphreys-Pereira, Danny A; Elling, Axel A

    2014-01-01

    Root-knot nematodes (Meloidogyne spp.) are among the most important plant pathogens. In this study, the mitochondrial (mt) genomes of the root-knot nematodes, M. chitwoodi and M. incognita were sequenced. PCR analyses suggest that both mt genomes are circular, with an estimated size of 19.7 and 18.6-19.1kb, respectively. The mt genomes each contain a large non-coding region with tandem repeats and the control region. The mt gene arrangement of M. chitwoodi and M. incognita is unlike that of other nematodes. Sequence alignments of the two Meloidogyne mt genomes showed three translocations; two in transfer RNAs and one in cox2. Compared with other nematode mt genomes, the gene arrangement of M. chitwoodi and M. incognita was most similar to Pratylenchus vulnus. Phylogenetic analyses (Maximum Likelihood and Bayesian inference) were conducted using 78 complete mt genomes of diverse nematode species. Analyses based on nucleotides and amino acids of the 12 protein-coding mt genes showed strong support for the monophyly of class Chromadorea, but only amino acid-based analyses supported the monophyly of class Enoplea. The suborder Spirurina was not monophyletic in any of the phylogenetic analyses, contradicting the Clade III model, which groups Ascaridomorpha, Spiruromorpha and Oxyuridomorpha based on the small subunit ribosomal RNA gene. Importantly, comparisons of mt gene arrangement and tree-based methods placed Meloidogyne as sister taxa of Pratylenchus, a migratory plant endoparasitic nematode, and not with the sedentary endoparasitic Heterodera. Thus, comparative analyses of mt genomes suggest that sedentary endoparasitism in Meloidogyne and Heterodera is based on convergent evolution.

  2. Activity of Hydroxamic Acids from Secale cereale Against the Plant-Parasitic Nematodes Meloidogyne incognita and Xiphinema americanum.

    Science.gov (United States)

    Zasada, I A; Meyer, S L F; Halbrendt, J M; Rice, C

    2005-10-01

    ABSTRACT Cyclic hydroxamic acids are secondary metabolites found in the family Poaceae and have been implicated in the allelopathy of rye (Secale cereale). The toxicity of these compounds against plant-parasitic nematodes is unknown. DIBOA (2,4-dihydroxy-(2H)-1,4-benzoxazin-3(4H)-one), DIMBOA (2,4-hydroxy-7-methoxy-(2H)-1,4-benzoxazin-3(4H)-one), and their degradation products BOA (benzoxazolin-2(3H)-one) and MBOA (6-methoxy-benzoxazolin-2(3H)-one) were screened in vitro against Meloidogyne incognita second-stage juveniles (J2) and eggs and mixed-stages of Xiphinema americanum. Xiphinema americanum was more sensitive to DIBOA and DIMBOA than M. incognita J2, with a maximum apparent mortality of 96 and 92% compared to 73 and 72% at 90 mug/ml. Eggs of M. incognita were less sensitive to the hydroxamic acids than J2; only DIBOA resulted in a 50% reduction in egg hatch, with a lethal concentration (LC(50)) of 74 mug/ml compared to 21 mug/ml for J2. When M. incognita J2 were exposed to DIBOA for 48 h and the compound was removed and replaced with water, the LC(50) value increased from 21.0 to 40.7 mug/ml. MBOA was not toxic to X. americanum or M. incognita eggs, but was toxic to M. incognita J2, with LC(50) values of 44 and 20 mug/ml before and after the compound was removed and replaced with water. BOA was the least toxic hydroxamic acid tested; it did not reduce M. incognita egg hatch after 1 week of exposure or increase X. americanum mortality after 24 h of exposure. While in vitro studies provide a valuable starting point in determining the toxicity of the chemical component of rye, the relevance of the data to soil remains to be determined.

  3. REPRODUÇÃO DE Meloidogyne incognita RAÇA 2 E DE Meloidogyne javanica EM OITO ESPÉCIES DE PLANTAS MEDICINAIS

    OpenAIRE

    MACIEL,S.L.; L.C.C.B. Ferraz

    1996-01-01

    Avaliaram-se as taxas reprodutivas de Meloidogyne incognita raça 2 e de Meloidogyne javanica em oito espécies de plantas consideradas medicinais, em vasos com 500 ml de solo, sob condição de casa de vegetação. Cada planta foi inoculada com 5000 ovos, em média, estabelecendo-se cinco repetições. Realizaram-se as avaliações após 45 a 55 dias das inoculações, com base nos índices de massas de ovos e nos fatores de reprodução dos nematóides. Achillea millefolium (mil-folhas), Arctium lappa (barda...

  4. Resistência de clones de umezeiro e cultivares de pessegueiro a Meloidogyne incognita (nemata: Heteroderidae Resistance of mume clones and peach tree cultivars to Meloidogyne incognita (nemata: heteroderidae

    Directory of Open Access Journals (Sweden)

    Newton Alex Mayer

    2005-08-01

    Full Text Available O presente estudo teve por objetivo avaliar a reação dos Clones 05; 10 e 15 de umezeiro (Prunus mume Sieb. et Zucc. e das cultivares Okinawa, Aurora-1 e Dourado-1 de pessegueiro [Prunus persica (L. Batsch] a Meloidogyne incognita (Kofoid and White Chitwood, em condições de casa de vegetação. As plantas foram mantidas em vasos de cerâmica contendo uma mistura de solo e areia (1:1, v/v, previamente autoclavada a 121ºC e 1kgf.cm-2 por 2 horas. Aos 60 dias após o plantio, cada planta foi inoculada com 2.000 ovos e juvenis de segundo estádio de Meloidogyne incognita. O experimento foi conduzido em delineamento inteiramente casualizado, com 6 tratamentos (genótipos e 9 repetições. Transcorridos 116 dias após a inoculação, as plantas foram colhidas para avaliação do sistema radicular. Foi possível verificar que o número de galhas por sistema radicular, o número de ovos e juvenis por 10g de raízes e por sistema radicular foi nulo ou praticamente nulo em todos os clones e nas cultivares estudadas, de forma que os respectivos fatores de reprodução foram todos inferiores a 1. Conclui-se que os Clones 05; 10 e 15 de umezeiro, assim como as cultivares Okinawa, Aurora-1 e Dourado-1 de pessegueiro são resistentes a Meloidogyne incognita.The present study had for objective to study the reaction of mume Clones 05, 10 and 15 (Prunus mume Sieb. et Zucc. and 'Okinawa', 'Aurora-1' and 'Dourado-1' peach tree cultivars [Prunus persica (L. Batsch] to Meloidogyne incognita (Kofoid and White Chitwood, in greenhouse conditions. The plants were maintained in ceramic boxes containing a soil-sand mixture (1:1, v/v, previously autoclaved at 121ºC and 1 kgf.cm-2 for 2 hours. On the sixtieth day after planting, each plant was inoculated with 2,000 eggs in the second stage juvenile of Meloidogyne incognita. The experiment was carried out in randomized design with 6 treatments (genotypes and 9 repetitions. After 116 days from inoculation, plants were

  5. Isolation of Nematicidal Triterpenoid Saponins from Pulsatilla koreana Root and Their Activities against Meloidogyne incognita

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    Byung Soo Han

    2013-05-01

    Full Text Available Pulsatilla koreana, a species endemic to Korea, is an important herb used in traditional medicine to treat amoebic dysentery and malaria. In the present study, 23 oleanane-type triterpenoid saponins 1–23 and eight lupane-type triterpenoid saponins 24–31 were isolated from the roots of P. koreana. Their structures were elucidated on the basis of spectroscopic data. The methanol extract and isolated compounds were next assessed for nematicidal activity against the root-knot nematode (Meloidogyne incognita. The methanol extract showed strong nematicidal activity after 48 h, with a LC50 value of 92.8 μg/mL. Compounds 2, 5, 9, 20, and 21 showed significant effects, with LC50 values ranging from 70.1 to 94.7 μg/mL after 48 h. These results suggest that triterpenoid saponins from P. koreana should be explored as potential natural nematicides for developing new agents to control root-knot nematode disease

  6. Relative Efficacy of Selected Volatile and Nonvolatile Nematicides for Control of Meloidogyne incognita on Tobacco.

    Science.gov (United States)

    Brodie, B B; Good, J M

    1973-01-01

    Root-knot nematode control and tobacco yields in plots infested with Meloidogyne incognita and treated with the nonvolatile nematicides, aldicarb, Mocap (R), or Nemacur (R) were greater than those on similar plots treated with volatile nematicides such as DD, DD + MENCS, SD14647 or tetrachlorothiophene. Root-knot control and tobacco yields in plots treated with carbofuran or Dasanit (R) were eqtual to that obtained with DD + MENCS, but less than that obtained with the other volatile soil nematicides. The most efficient dosage was 3.4 kg/hectare active ingredient for aldicarb and Mocap (R) and 10.0 kg/hectare for Dasanit (R). Carbofuran and Nemacur (R) were equally as effective at 4.2 kg/hectare as they were at higher dosages. The most efficient dosage of DD and SD14647 was 84 liters/hectare. Aldicarb and Dasanit (R) resulted in better nematode control and tobacco yields when incorporated into the top 15-20 cm of soil than when incorporated into the top 5-10 cm of soil. Nemacur (R) and Mocap (R) performed better when incorporated into the top 5-10 cm of soil, and carbofuran performed better when applied in the seed furrow (placed 15-20 cm deep in a 5-cm band and bedded).

  7. Efeitos do nível de inóculo de Meloidogyne incognita em algodoeiro Effects of low inoculum level of Meloidogyne incognita on cotton plants

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    MARLUCI MUNDIN ABRÃO

    2001-01-01

    Full Text Available Pesquisas acerca da fisiologia de plantas em resposta ao ataque de nematóides normalmente são feitas com doses altas de inóculo, quer sejam ovos ou juvenis de segundo estágio. Diferentemente, as avaliações da resistência de plantas a nematóides em programas de melhoramento são realizadas com doses bastante inferiores. Neste estudo acompanhou-se a variação de alguns parâmetros fisiológicos em algodão, em resposta à aplicação de baixas doses de inóculo de Meloidogyne incognita raça 3. Duas cultivares foram utilizadas, Acala e IAC-20, respectivamente suscetível e moderadamente resistente. Plântulas com duas folhas receberam 500 ou 5.000 ovos e, 90 dias depois, foram comparadas a plantas que não receberam o inóculo, quanto à massa da parte aérea e raízes, fotossíntese, atividade da enzima redutase do nitrato e teores de clorofila e açúcares solúveis. Aos 90 dias algumas plantas também foram submetidas à deficiência hídrica e o potencial da água determinado nas folhas. O maior nível de inóculo levou à redução da parte aérea (massa de folhas em 'Acala'. Com 500 ovos parece ter ocorrido um estímulo em ambas as cultivares, uma vez que houve tendência de maior crescimento da parte aérea. Em 'Acala' houve maior crescimento de raiz com o aumento do inóculo, provavelmente devido à emissão de raízes secundárias nos pontos de penetração do nematóide e também pela formação de galhas. Houve aumento dos teores de clorofila e de açúcares solúveis, bem como da fotossíntese, com o aumento do inóculo. Discute-se se tal ocorrência deve-se à maior demanda de fotoassimilados para suportar o crescimento de raízes, em 'Acala'. Em IAC-20 esse fato estaria ligado aos mecanismos de defesa induzidos pelo ataque do nematóide. Após o estresse hídrico o potencial da água diminuiu em 'IAC-20' e aumentou na 'Acala', com o aumento do inóculo. A elevação do potencial da água, nesta última cultivar, poderia

  8. Reação de genótipos de milho ao parasitismo de Meloidogyne incognita raça 1 e a M. paranaensis = Reaction of corn genotypes to parasitism from Meloidogyne incognita breed 1 and M. paranaensis

    Directory of Open Access Journals (Sweden)

    Ricardo Michael Levy

    2009-10-01

    Full Text Available O uso de híbridos e genótipos de milho resistentes aos nematóides formadores de galhas em sistemas de rotação de culturas mantém sua população em níveis baixos, diminuindo as perdas e possibilitando, posteriormente, o uso de genótipos mais suscetíveis. No presentetrabalho, foi avaliada a resistência de 18 genótipos de milho ao parasitismo de M. paranaensis e a M. incognita raça 1 em casa-de-vegetação. As plantas foram inoculadas com 5.000 ovos e eventuaisjuvenis dos respectivos nematóides. O delineamento utilizado foi inteiramente ao acaso, com dez repetições para cada tratamento com os nematóides e cinco repetições para a testemunha sem inoculação. Também foi realizada a técnica de coloração das raízes com fucsina ácida, pelo método de Byrd et al. (1972. Sessenta dias após a inoculação, os sistemas radiculares foram coletados, lavados e avaliados quanto à penetração, produção de ovos e estimativa do Fator de Reprodução (FR. Os resultados mostraram que, para M. paranaensis, o FR variou de 0,01 a 0,08;para M. incognita, a variação foi de 0,01 a 0,03, mostrando que todos os genótipos se comportaram como resistentes, apresentando FR The use of corn hybrids and genotypes resistant to root-knot nematodes in crop rotation systems reduce the population of nematodes, preventing losses and allowing for the use of more susceptible genotypes. In this study, the resistance of eighteen hybrids of corn to parasitism of Meloidogyne paranaensis and M. incognita breed 1 were evaluated in a greenhouse. The plants were inoculated with 5,000 eggs and possible juveniles of each nematode in a completely randomized design, using ten replicates for eachtreatment with nematodes, and five replicates for the treatment without inoculation (control. The root staining technique using acid fuchsin was also applied, according to Byrd et al. (1972. Sixty days after the inoculation, the roots systems were collected, washedand evaluated

  9. Resistance to root-knot nematodes (Meloidogyne spp. in tomato: Mi gene and occurrence of virulent populations

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    Gökhan AYDINLI

    2015-12-01

    Full Text Available Root-knot nematodes (Meloidogyne spp. are one of the most important agricultural pests that cause serious yield losses in tomato. Resistant tomato cultivars have commonly been used in both conventional and organic agriculture. In tomato, resistance to three most prevalent species of root-knot nematode, Meloidogyne arenaria, Meloidogyne incognita, Meloidogyne javanica, is controlled by the Mi-1 gene. However, there are two major limiting factors for efficiency of Mi-1 gene: High soil temperature and occurrence of resistance-breaking (virulent populations. These populations can emerge either naturally or after repeated exposure on tomatoes with Mi-1 gene. This review summarizes information on some strategies to prevent the emergence of virulent populations and to preserve the durability of plant resistance to Mi-1 gene.

  10. 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. PMID:28120937

  11. 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.

  12. Does the Presence of Detached Root Border Cells of Zea mays Alter the Activity of the Pathogenic Nematode Meloidogyne incognita?

    Science.gov (United States)

    Rodger, S; Bengough, A G; Griffiths, B S; Stubbs, V; Young, I M

    2003-09-01

    ABSTRACT The root-knot nematode Meloidogyne incognita is a major pathogen of a range of important crops. Currently, control is typically achieved by the use of nematicides. However, recent work suggests that manipulating the ability of roots to slough off border cells, which then act as a decoy to the nematode, can significantly decrease damage to the roots. We investigated the attractiveness of border cells to M. incognita and the response of the nematode to border cells in close proximity. We found very limited attraction, in that nematodes did not preferentially alter direction to move toward the border cells, but a large and significant increase in nematode speed was observed once they were in the immediate vicinity of border cells. We discuss the results in the context of physical and biological mechanisms in relation to the control of pathogenic nematodes.

  13. Genome-wide survey and analysis of microsatellites in nematodes, with a focus on the plant-parasitic species Meloidogyne incognita

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    Guillemaud Thomas

    2010-10-01

    Full Text Available Abstract Background Microsatellites are the most popular source of molecular markers for studying population genetic variation in eukaryotes. However, few data are currently available about their genomic distribution and abundance across the phylum Nematoda. The recent completion of the genomes of several nematode species, including Meloidogyne incognita, a major agricultural pest worldwide, now opens the way for a comparative survey and analysis of microsatellites in these organisms. Results Using MsatFinder, the total numbers of 1-6 bp perfect microsatellites detected in the complete genomes of five nematode species (Brugia malayi, Caenorhabditis elegans, M. hapla, M. incognita, Pristionchus pacificus ranged from 2,842 to 61,547, and covered from 0.09 to 1.20% of the nematode genomes. Under our search criteria, the most common repeat motifs for each length class varied according to the different nematode species considered, with no obvious relation to the AT-richness of their genomes. Overall, (ATn, (AGn and (CTn were the three most frequent dinucleotide microsatellite motifs found in the five genomes considered. Except for two motifs in P. pacificus, all the most frequent trinucleotide motifs were AT-rich, with (AATn and (ATTn being the only common to the five nematode species. A particular attention was paid to the microsatellite content of the plant-parasitic species M. incognita. In this species, a repertoire of 4,880 microsatellite loci was identified, from which 2,183 appeared suitable to design markers for population genetic studies. Interestingly, 1,094 microsatellites were identified in 801 predicted protein-coding regions, 99% of them being trinucleotides. When compared against the InterPro domain database, 497 of these CDS were successfully annotated, and further assigned to Gene Ontology terms. Conclusions Contrasted patterns of microsatellite abundance and diversity were characterized in five nematode genomes, even in the case of

  14. Effects of ced-9 dsRNA on Caenorhabditis elegans and Meloidogyne incognita

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    Robert T. Gaeta

    2011-01-01

    Full Text Available Problem Statement: In metazoans Programmed Cell Death (PCD is essential for proper development. Suppression of PCD is needed to guarantee cell survival and in the nematode Caenorhabditis elegans the regulation of PCD is accomplished by the function of the ced-9 gene. Approach: In this work the use of double stranded RNA (dsRNA to knock-down ced-9 gene function was tested as means to induce PCD. Results: Our results indicate that dsRNA targeting the cell death protection gene ced-9 is effective at decreasing the fecundity of C. elegans by up to 21%. The decreased fecundity correlated with an increased presence of cell corpses in developing embryos. Endogenous ced-9 transcript levels were reduced in progeny of ced-3 mutant nematodes fed bacteria expressing ced-9 dsRNA. These data suggest that nematode fecundity can be reduced by ingestion and exposure to dsRNAs targeting regulation of the cell death pathway. In an attempt to determine if plant parasitic nematodes are susceptible to the targeting of the PCD regulatory pathway we exposed Meloidogyne incognita, a plant parasitic nematode, to ced-9 dsRNA; here we show that this exposure results in decreased gall formation in the tobacco plants. Conclusion/Recommendations: Our results provide the first steps toward using RNAi technologies to attempt nematode control by targeting cell death pathways. Ongoing research with transgenic plants designed to express dsRNA for ced-9-like sequences will further test the feasibility of generating plants with RNAi-based resistance to parasitic nematodes.

  15. Nematicidal Activity of the Volatilome of Eruca sativa on Meloidogyne incognita.

    Science.gov (United States)

    Aissani, Nadhem; Urgeghe, Pietro Paolo; Oplos, Chrisostomos; Saba, Marco; Tocco, Graziella; Petretto, Giacomo Luigi; Eloh, Kodjo; Menkissoglu-Spiroudi, Urania; Ntalli, Nikoletta; Caboni, Pierluigi

    2015-07-15

    Research on new pesticides based on plant extracts, aimed at the development of nontoxic formulates, has recently gained increased interest. This study investigated the use of the volatilome of rucola (Eruca sativa) as a powerful natural nematicidal agent against the root-knot nematode, Meloidogyne incognita. Analysis of the composition of the volatilome, using GC-MS-SPME, showed that the compound (Z)-3-hexenyl acetate was the most abundant, followed by (Z)-3-hexen-1-ol and erucin, with relative percentages of 22.7 ± 1.6, 15.9 ± 2.3, and 8.6 ± 1.3, respectively. Testing of the nematicidal activity of rucola volatile compounds revealed that erucin, pentyl isothiocyanate, hexyl isothiocyanate, (E)-2-hexenal, 2-ethylfuran, and methyl thiocyanate were the most active with EC50 values of 3.2 ± 1.7, 11.1 ± 5.0, 11.3 ± 2.6, 15.0 ± 3.3, 16.0 ± 5.0, and 18.1 ± 0.6 mg/L, respectively, after 24 h of incubation. Moreover, the nematicidal activity of fresh rucola used as soil amendant in a containerized culture of tomato decreased the nematode infection in a dose-response manner (EC50 = 20.03 mg/g) and plant growth was improved. On the basis of these results, E. sativa can be considered as a promising companion plant in intercropping strategies for tomato growers to control root-knot nematodes.

  16. Sampling techniques and detection methods for developing risk assessments for root-knot nematode (Meloidogyne incognita) on lima bean (Phaseolus lunatus) in the Mid-Atlantic region

    Science.gov (United States)

    Lima bean, Phaseolus lunatus, is a cornerstone crop in the Mid-Atlantic region and Meloidogyne incognita, the southern root knot nematode (RKN), causes significant yield loss. The RKN has become more pervasive as toxic nematicides have been removed from the market, and risk evaluation research is ne...

  17. Genomes of parasitic nematodes (Meloidogyne hapla, Meloidogyne incognita, Ascaris suum and Brugia malayi) have a reduced complement of small RNA interference pathway genes: knockdown can reduce host infectivity of M. incognita.

    Science.gov (United States)

    Iqbal, Sadia; Fosu-Nyarko, John; Jones, Michael G K

    2016-07-01

    The discovery of RNA interference (RNAi) as an endogenous mechanism of gene regulation in a range of eukaryotes has resulted in its extensive use as a tool for functional genomic studies. It is important to study the mechanisms which underlie this phenomenon in different organisms, and in particular to understand details of the effectors that modulate its effectiveness. The aim of this study was to identify and compare genomic sequences encoding genes involved in the RNAi pathway of four parasitic nematodes: the plant parasites Meloidogyne hapla and Meloidogyne incognita and the animal parasites Ascaris suum and Brugia malayi because full genomic sequences were available-in relation to those of the model nematode Caenorhabditis elegans. The data generated was then used to identify some potential targets for control of the root knot nematode, M. incognita. Of the 84 RNAi pathway genes of C. elegans used as model in this study, there was a 42-53 % reduction in the number of effectors in the parasitic nematodes indicating substantial differences in the pathway between species. A gene each from six functional groups of the RNAi pathway of M. incognita was downregulated using in vitro RNAi, and depending on the gene (drh-3, tsn-1, rrf-1, xrn-2, mut-2 and alg-1), subsequent plant infection was reduced by up to 44 % and knockdown of some genes (i.e. drh-3, mut-2) also resulted in abnormal nematode development. The information generated here will contribute to defining targets for more robust nematode control using the RNAi technology.

  18. Activity of chalcones derived from 2,4,5-trimethoxybenzaldehyde against Meloidogyne exigua and in silico interaction of one chalcone with a putative caffeic acid 3-O-methyltransferase from Meloidogyne incognita.

    Science.gov (United States)

    Nunes, Alexandro Silva; Campos, Vicente Paulo; Mascarello, Alessandra; Stumpf, Taisa Regina; Chiaradia-Delatorre, Louise Domenghini; Machado, Alan Rodrigues Teixeira; Santos Júnior, Helvécio Martins; Yunes, Rosendo Augusto; Nunes, Ricardo José; Oliveira, Denilson Ferreira

    2013-12-01

    Meloidogyne exigua is a parasitic nematode of plants that causes great losses to coffee farmers. In an effort to develop parasitic controls, 154 chalcones were synthesized and screened for activity against this nematode. The best results were obtained with (2E)-1-(4'-nitrophenyl)-3-(2,4,5-trimethoxyphenyl)prop-2-en-1-one (6) with a 50% lethal concentration (LC50) of 171 μg/ml against M. exigua second-stage juveniles, in comparison to the commercially-available nematicide carbofuran which had an LC50 of 260 μg/ml under the same conditions. When coffee plants were used, 6 reduced the nematode population to ~50% of that observed in control plants. To investigate the mechanism of action of 6, an in silico study was carried out, which indicated that 6 may act against M. exigua through inhibition of a putative caffeic acid 3-O-methyltransferase homodimer, the amino acid sequence of which was determined by examining the genome of Meloidogyne incognita.

  19. Efeito de extratos aquosos de espécies de Asteraceae sobre Meloidogyne incognita

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    Isabel Cristina Madeira Ferreira

    2013-03-01

    Full Text Available Estudou-se, in vitro e in vivo a atividade nematicida dos extratos aquosos de vedélia (Sphagneticola trilobata, erva-de-touro (Tridax procumbens, cravo-de-defunto (Tagetes patula, girassol mexicano (Tithonia diversifolia, botão de ouro (Unxia suffruticosa e zínia (Zinnia peruviana, sobre Meloidogyne incognita. Os extratos foram preparados na proporção de 1,0g do material seco e triturado para 10mL de água destilada e armazenados por 24h, sendo seguidamente utilizados nos experimentos. Nos testes in vitro, foram depositados 4,0mL do extrato bruto e 2,0mL de uma suspensão aquosa contendo 200 ovos do nematóide em placas de Petri de 5cm de diâmetro e, quinze dias após, procedeu-se a contagem do número de juvenis eclodidos e dos ovos remanescentes para o cálculo das porcentagens de eclosão. Nos testes in vivo, os extratos foram aplicados, separadamente, via pulverização foliar, tratamento de raiz e vertido no solo, semanalmente durante 60 dias. Como testemunha utilizou-se apenas água nos dois experimentos. No ensaio in vitro observou-se que todos os extratos foram eficientes na redução da eclosão de juvenis de M. incognita quando comparados à testemunha, as porcentagens de redução foram 89,96%, 91,13%, 92,48%, 92,72%, 93,2% e 97,48% para erva-de-touro, cravo-de-defunto, girassol mexicano, vedélia, botão de ouro e zínia, respectivamente, e no ensaio in vivo, que os tratamentos não exerceram nenhum efeito sobre o peso do sistema radicular dos tomateiros, no entanto, observou-se que os resultados diferiram entre as espécies utilizadas e a forma de aplicação do extrato na avaliação do peso fresco da parte aérea das plantas. Quanto ao fator de reprodução, observou-se que nenhum dos extratos apresentou diferença estatística em relação à testemunha, no entanto, quando se compara as diferentes formas de aplicação dos mesmos, observa-se que houve diferença estatística quando os extratos de erva de touro e girassol

  20. Preliminary evaluation of meloidogyne incognita race 3 reproduction on garden pea cultivars in Brazil/ Avaliação preliminar da reprodução de Meloidogyne incognita raça 3 em cultivares de ervilha no Brasil

    Directory of Open Access Journals (Sweden)

    Luiz Carlos Camargo Barbosa Ferraz

    2000-01-01

    Full Text Available Thirteen garden pea cultivars, were assessed for the reproductive rate of the root-knot nematode Meloidogyne incognita race 3 under greenhouse conditions. Two-week old plants growing were inoculated with 5.000 eggs. The nematode reproduction data was determined 55 days later according to the three adopted evaluation criteria (root-gall and egg-mass indexes, reproduction factor, percentage of reduction of the reproduction factor in relation to the susceptible standard cultivar. The tested cultivars were rated as highly susceptible ('Trolly'. 'Jurema', susceptible ('Luiza'. 'Mini'. 'Asterix', 'Verde Temprana' or moderately susceptible ('Marina', 'Telephone'., 'Dileta'. 'Bolero', 'Flávia'. 'Viçosa', and 'Maria' hosts for the nematode.Avaliaram-se as taxas reprodutivas e caracterizaram-se as reações de 13 cut tiveres de ervilha em relação ao nematóide de galhas Meloidogyne incognita raça 3, em casa-de-vegetação. Plantas com duas semanas de idade, foram inoculadas com 5000 ovos do nematóide. As avaliações foram realizadas após 55 dias com base nos critérios - índices de galhas/índices de massas de ovos, fator de reprodução e porcentagem de redução do fator de reprodução. Duas cultivares foram consideradas hospedeiras altamente suscetíveis (‘Trolly’, ‘Jurema’, cinco suscetíveis ('Luíza', 'Mini', 'Asterix', 'Verde Temprana', 'Telefone' e seis moderadamente suscetíveis ('Marina'. 'Dileta', 'Boiero'. 'Flávia'. 'Viçosa', 'Maria'.

  1. Preplanting tall fescue grass for controlling Meloidogyne incognita in a young peach orchard

    Science.gov (United States)

    Preplant fumigant nematicides have traditionally been used to control Meloidogyne spp. in peach in the southeastern United States. The current preplant nematicides recommended for managing Meloidogyne spp. in peach include the soil fumigants, 1,3-dichloropropene and metam sodium. Because the econo...

  2. Management of Meloidogyne incognita with tall fescue grass rotations prior to peach orchard establishment

    Science.gov (United States)

    Root-knot nematodes (Meloidogyne spp.) are important pests of peach in the USA. Preplant fumigant nematicides have been used to control Meloidogyne spp. associated with Southeastern peach production. Unfortunately, growers have increasingly faced economic challenges, making it difficult for them t...

  3. Bioefficacy evaluation of controlled release formulations based on amphiphilic nano-polymer of carbofuran against Meloidogyne incognita infecting tomato.

    Science.gov (United States)

    Pankaj; Shakil, Najam Akhtar; Kumar, Jitendra; Singh, M K; Singh, Khajan

    2012-01-01

    In the present investigation, the bioefficacy of developed carbofuran formulations, with PEG-600 (7a, CP1) & PEG-900 (7b, CP2) @ 5, 10 and 20 ppm, along with commercial formulation of carbofuran 3G (CP0) were evaluated against the root-knot nematode, Meloidogyne incognita infecting tomato (cv. Pusa Ruby) in pot and field conditions. The bioefficacy data indicated that the formulations developed by utilizing polymers having PEG - 900 (7b) as hydrophilic segment were effective even at 14 days post inoculation (dpi) as evident from shoot and root length. Also, the reduction in penetration was found to be maximum with CP2 (3.6 - 4.6 J2s) at all concentrations compared to CP1 (6.6-16.4 J2s) and CP0 (29.3-32.6 J2s). Overall, CP2 was more effective in reducing the number of nematodes up to 14 days, compared to CP1 and CP0. Both the CR formulations (CP1 and CP2) in general significantly reduced the number of galls, when compared to CP0. However, under field conditions, lower concentrations (5, and 10 ppm) of CP2, were less effective in controlling the gall formation whereas, CP2 at 20 ppm, was most effective than other treatments. The study revealed that the developed CR formulations of carbofuran have the potential for effective management of M. incognita in tomato under field conditions.

  4. Microbial modulation of bacoside A biosynthetic pathway and systemic defense mechanism in Bacopa monnieri under Meloidogyne incognita stress

    Science.gov (United States)

    Gupta, Rupali; Singh, Akanksha; Srivastava, Madhumita; Singh, Vivek; Gupta, M. M.; Pandey, Rakesh

    2017-01-01

    Plant-associated beneficial microbes have been explored to fulfill the imperative function for plant health. However, their impact on the host secondary metabolite production and nematode disease management remains elusive. Our present work has shown that chitinolytic microbes viz., Chitiniphilus sp. MTN22 and Streptomyces sp. MTN14 singly as well as in combination modulated the biosynthetic pathway of bacoside A and systemic defense mechanism against Meloidogyne incognita in Bacopa monnieri. Interestingly, expression of bacoside biosynthetic pathway genes (3-Hydroxy-3-methylglutaryl coenzyme A reductase, mevalonate diphosphate decarboxylase, and squalene synthase) were upregulated in plants treated with the microbial combination in the presence as well as in absence of M. incognita stress. These microbes not only augmented bacoside A production (1.5 fold) but also strengthened host resistance via enhancement in chlorophyll a, defense enzymes and phenolic compounds like gallic acid, syringic acid, ferulic acid and cinnamic acid. Furthermore, elevated lignification and callose deposition in the microbial combination treated plants corroborate well with the above findings. Overall, the results provide novel insights into the underlying mechanisms of priming by beneficial microbes and underscore their capacity to trigger bacoside A production in B. monnieri under biotic stress. PMID:28157221

  5. Chitosan-cinnamon beads enhance suppressive activity against Rhizoctonia solani and Meloidogyne incognita in vitro.

    Science.gov (United States)

    Seo, Dong-Jun; Nguyen, Dang-Minh-Chanh; Park, Ro-Dong; Jung, Woo-Jin

    2014-01-01

    A novel chitosan-cinnamon bead carrier was prepared in this study. Chitosan was mixed with cinnamon powder (CP) and cinnamon extract (CE) to obtain chitosan-cinnamon powder (CCP) beads and chitosan-cinnamon extracted (CCE) beads, respectively. The potential antifungal and nematicidal activities of CCP and CCE were investigated against Rhizoctonia solani and Meloidogyne incognita in vitro. Relative antifungal activity of the CCP (5% CP) bead-treated R. solani was 30.9 and 23.9% after 1 and 2 day incubations, respectively. Relative antifungal activity of the CCE (0.5% CE) bead-treated R. solani was 4.3, 3.0 and 4.2% after 1, 2 and 3 days of incubation. Inhibition of hatch by CCP beads with CP of 5% was 78.8%. Inhibition of hatch by CCE beads with CE of 0.5% was 82.0%. J2 mortality following the CCP (5% CP) and CCE (0.5% CE) bead treatments was 85.0 and 95.8%, respectively against M. incognita after 48 h incubations.

  6. Sources for Heat-Stable Resistance to Southern Root-Knot Nematode(Meloidogyne incognita) in Solanum lycopersicum

    Institute of Scientific and Technical Information of China (English)

    WU Wen-wen; SHEN Huo-lin; YANG Wen-cai

    2009-01-01

    Southern root-knot nematode (Meloidogyne incognita) is a major problem in vegetable production in China due to the expansion of plastic tunnel and solar greenhouse.Using resistant cultivars is an effective approach to control the disease.Nine genes,Mi-1 to Mi-9,have been reported and only Mi-1 has been successfully used in tomato breeding.However,Mi-1 is inactive at a temperature above 28℃.In order to identify sources for heat-stable resistance to southern root-knot nematode,53 genotypes of tomato (Solanum spp.) were inoculated with an isolate of M.incognita in the growth chamber at 28 or 32℃ for initial screening.28 lines had less than 25 galls and were considered as resistant candidates.The top 60% (16 in total) of resistant candidates obtained from each temperature were subject to re-evaluation at 32℃ using the same nematode isolate.Three lines ZN17,ZN 48,and LA0385 showed heat-stable resistance with an average of 10 galls or less per plant.LA0385 is a wild species,while ZN 17 and ZN48 are elite breeding lines.These lines were grown in a greenhouse for two seasons,and also showed high resistance with less than 10 galls per plant.Thus they were considered as good sources for breeding resistance to southern root-knot nematode in tomato.

  7. Seleção de clones de batata-doce resistentes a Meloidogyne incognita raça 1 Selection of sweetpotato clones resistant to Meloidogyne incognita race 1

    Directory of Open Access Journals (Sweden)

    Aline Marchese

    2010-09-01

    Full Text Available O objetivo deste trabalho foi selecionar clones de batata-doce (Ipomoea batatas resistentes à raça 1 de Meloidogyne incognita e avaliar a eficiência do método de seleção empregado, pela estimação dos coeficientes de variação genética e ambiental e das herdabilidades no sentido amplo. Foram utilizados 123 genótipos de batata-doce, entre os quais quatro cultivares comerciais - Brazlândia Rosada, Brazlândia Roxa, Brazlândia Branca e Palmas -, e 119 acessos previamente selecionados no programa de melhoramento vegetal da Universidade Federal de Lavras. O delineamento experimental utilizado foi o de blocos aumentados, com três tratamentos comuns: as cultivares de batata-doce Brazlândia Branca e Palmas, e a cultivar de tomate Santa Clara, suscetível ao nematoide. A classificação dos níveis de resistência foi realizada de acordo com o fator de reprodução do nematoide e o índice de reprodução relativo à cultivar Santa Clara, de tomateiro. A relação entre os coeficientes de variação genética e ambiental e as herdabilidades no sentido amplo foram altas, tanto para o fator de reprodução quanto para o índice de reprodução dos nematoides, o que demonstra a eficiência do método empregado para a seleção de genótipos resistentes. Foram identificados 57 genótipos promissores de batata-doce, resistentes à raça 1 de M. incognita, e selecionados para continuar no programa de melhoramento.The objective of this work was to select sweetpotato (Ipomoea batatas resistant clones to Meloidogyne incognita race 1, and to assess the efficiency of the selection method deployed, through the estimation of genetic and environmental coefficients of variation, and broad-sense heritabilities. Genotypes assessed comprised 123 sweetpotato entries altogether, including four commercial cultivars - Brazlândia Rosada, Brazlândia Roxa, Brazlândia Branca, Palmas - and 119 clones previously selected by the Universidade Federal de Lavras

  8. Uso de agentes microbianos e químico para o controle de Meloidogyne incognita em soja = Use of microbial and chemical agents to control Meloidogyne incognita in soybean

    Directory of Open Access Journals (Sweden)

    Henrique Teixeira Nunes

    2010-07-01

    Full Text Available Nematoides de galhas constituem importante grupo de patógenos da cultura da soja e o manejo integrado é uma das principais medidas de controle que visam à redução de perdas econômicas. Neste trabalho foi avaliada a eficácia dos fungos Paecilomyces lilacinus (Thom. Samsom e Pochonia chlamydosporia (Goddard Zare & Gams (sinonímia Verticillium chlamydosporium, de um produto comercial à base de Bacillus sp. (Nemix e do nematicida químico Aldicarb no controle de Meloidogyne incognita em soja, variedade M-SOY 6101. O experimento foi realizado em casa-de-vegetação no delineamento experimental de blocos casualizados com nove tratamentos (três produtos biológicos usados no tratamento de sementes com ou sem a aplicação em pós-emergência, Aldicarb aplicado apenas em pós-emergência e duastestemunhas e quatro repetições. Aldicarb reduziu o número de ovos e de juvenis do nematoide. P. lilacinus foi o mais atuante dos agentes biológicos, favorecendo a manutenção da quantidade de matéria seca da raiz de soja e reduzindo o número de ovos. O produto Nemix e P. chlamydosporia somente tiveram ação efetiva na redução do número de ovos do nematoide. Com base nos resultados, foi possível concluir que o agente químico e os agentes biológicos avaliados neste trabalho tiveram moderada atividade no controle de M. incognita em soja.Root-knot nematodes are considered significant pathogens of soybean crops. The objective of this work was to evaluate the efficacy of two fungi (Paecilomyces lilacinus (Thom. Samsom and Pochonia chlamydosporia (Goddard Zare & Gams (syn. Verticillium chlamydosporium, a commercial product based on Bacillus sp. and Aldicarb on the control of Meloidogyne incognita on soybean, cultivar M-SOY 6101. The experimental design was set as randomized blocks with four replications. Nine treatments were evaluated: three biological agents used for seed treatment with and without post-emergence application, Aldicarb on post

  9. Interactions between an arbuscular mycorrhizal fungus (Scutellospora heterogama and the root-knot nematode (Meloidogyne incognita on sweet passion fruit (Passiflora alata

    Directory of Open Access Journals (Sweden)

    Érika Cristina Teixeira dos Anjos

    2010-08-01

    Full Text Available The effects of inoculation of sweet passion fruit plants with the arbuscular mycorrhizal (AM fungus Scutellospora heterogama on the symptoms produced by Meloidogyne incognita race 1 and its reproduction were evaluated in two greenhouse experiments. In the 1st, the M. incognita (5000 eggs/plant and S. heterogama (200 spores/plant inoculations were simultaneous; in the 2nd, the nematodes were inoculated 120 days after the fungal inoculation. In both the experiments, 220 days after AM fungal inoculation, plant growth was stimulated by the fungus. In disinfested soil, control seedlings (without S. heterogama were intolerant to parasitism of M. incognita, while the growth of mycorrhized seedlings was not affected. Sporulation of S. heterogama was negatively affected by the nematodes that did not impair the colonization. M. incognita did not affect mycorrhizal seedling growth. The establishment of mycorrhiza prior to the nematode infection contributed for the reduction of symptoms severity and reproduction of M. incognita in disinfested soil.O efeito da inoculação com Scutellospora heterogama (200 esporos/planta em relação aos sintomas e reprodução de Meloidogyne incognita raça 1 (5000 ovos/planta foi avaliado em plantas de maracujazeiro doce em dois experimentos em casa de vegetação. No primeiro experimento, inoculações com nematóide e FMA foram simultâneas; no segundo, nematóides foram inoculados 120 dias após o estabelecimento da simbiose micorrízica. Após o 220º dia da inoculação do FMA o fungo estimulou o crescimento da planta nos dois experimentos. No solo desinfestado as mudas não inoculadas com S. heterogama mostraram intolerância ao parasitismo de M. incognita. A esporulação de S. heterogama foi negativamente afetada pela presença do nematóide. M. incognita não afetou o crescimento das mudas micorrizadas ou o desenvolvimento do FMA. O estabelecimento da micorriza antes do nematóide contribui para a redução da

  10. Evaluation of the Effect of Ecologic on Root Knot Nematode, Meloidogyne incognita, and Tomato Plant, Lycopersicon esculenum

    Directory of Open Access Journals (Sweden)

    Gary W. Lawrence

    2008-06-01

    Full Text Available Nonchemical methods and strategies for nematode management including cultural methods and engineered measures have been recommended as an alternative to methyl bromide (a major soil fumigant, due to its role in the depletion of the ozone layer. Hence, an international agreement has recently been reached calling for its reduced consumption and complete phasing out. This present research evaluates the potential of Ecologic, a biological, marine shell meal chitin material, as a soil amendment management agent for root knot nematode, Meloidogyne incognita, control, and its effect on the growth of Floradel tomato plant, Lycopersicon esculentum. To accomplish this goal, studies were conducted during which, experimental pots were set up in greenhouse environments using sterilized soil inoculated with 5,000 root-knot eggs per 1500 g soil. There were 4 treatments and 5 replications. Treatments were: No chitin; 50 g chitin; 100 g chitin; and 200 g chitin. A two-week wait period following Ecologic amendment preceded Floradel tomato planting to allow breakdown of the chitin material into the soil. Fresh and dry weights of shoot and root materials were taken as growth end-points. A statistically significant difference (p ≤ 0.05 was obtained with regard to the growth rate of L. esculentum at 100 g chitin treatment compared to the control with no chitin. Mean fresh weights of Floradel tomato were 78.0 ± 22.3g, 81.0 ± 20.3g, 109.0 ± 25.4g and 102.0 ± 33.3g at 0, 50, 100 and 200g chitin, respectively. The analysis of root knot nematode concentrations indicated a substantial effect on reproduction rate associated with chitin amendment. Study results showed a significant decrease in both root knot nematode eggs and juveniles (J2 at 100g and 200g Ecologic chitin levels, however, an increase in nematode concentrations was recorded at the 50g Ecologic chitin level (p ≤ 0.05. The mean amounts of J2 population, as

  11. A Meloidogyne incognita effector is imported into the nucleus and exhibits transcriptional activation activity in planta.

    Science.gov (United States)

    Zhang, Lei; Davies, Laura J; Elling, Axel A

    2015-01-01

    Root-knot nematodes are sedentary biotrophic endoparasites that maintain a complex interaction with their host plants. Nematode effector proteins are synthesized in the oesophageal glands of nematodes and secreted into plant tissue through a needle-like stylet. Effectors characterized to date have been shown to mediate processes essential for nematode pathogenesis. To gain an insight into their site of action and putative function, the subcellular localization of 13 previously isolated Meloidogyne incognita effectors was determined. Translational fusions were created between effectors and EGFP-GUS (enhanced green fluorescent protein-β-glucuronidase) reporter genes, which were transiently expressed in tobacco leaf cells. The majority of effectors localized to the cytoplasm, with one effector, 7H08, imported into the nuclei of plant cells. Deletion analysis revealed that the nuclear localization of 7H08 was mediated by two novel independent nuclear localization domains. As a result of the nuclear localization of the effector, 7H08 was tested for the ability to activate gene transcription. 7H08 was found to activate the expression of reporter genes in both yeast and plant systems. This is the first report of a plant-parasitic nematode effector with transcriptional activation activity.

  12. Exploitation of microbes for enhancing bacoside content and reduction of Meloidogyne incognita infestation in Bacopa monnieri L.

    Science.gov (United States)

    Gupta, Rupali; Tiwari, Sudeep; Saikia, Shilpi K; Shukla, Virendra; Singh, Rashmi; Singh, S P; Kumar, P V Ajay; Pandey, Rakesh

    2015-01-01

    Despite the vast exploration of rhizospheric microbial wealth for crop yield enhancement, knowledge about the efficacy of microbial agents as biocontrol weapons against root-knot disease is scarce, especially in medicinal plants, viz., Bacopa monnieri. In the present investigation, rhizospheric microbes, viz., Bacillus megaterium, Glomus intraradices, Trichoderma harzianum ThU, and their combinations were evaluated for the management of Meloidogyne incognita (Kofoid and White) Chitwood and bacoside content enhancement in B. monnieri var CIM-Jagriti. A novel validated method Fourier transform near infrared was used for rapid estimation of total bacoside content. A significant reduction (2.75-fold) in root-knot indices was observed in the combined treatment of B. megaterium and T. harzianum ThU in comparison to untreated control plants. The same treatment also showed significant enhancement (1.40-fold) in total bacoside contents (plant active molecule) content using Fourier transform near-infrared (FT-NIR) method that analyses samples rapidly in an hour without solvent usage and provides ample scope for natural product studies.

  13. Transcriptome Analysis of Resistant and Susceptible Alfalfa Cultivars Infected With Root-Knot Nematode Meloidogyne incognita

    OpenAIRE

    Postnikova, Olga A.; Maria Hult; Jonathan Shao; Andrea Skantar; Nemchinov, Lev G.

    2015-01-01

    Nematodes are one of the major limiting factors in alfalfa production. Root-knot nematodes (RKN, Meloidogyne spp.) are widely distributed and economically important sedentary endoparasites of agricultural crops and they may inflict significant damage to alfalfa fields. As of today, no studies have been published on global gene expression profiling in alfalfa infected with RKN or any other plant parasitic nematode. Very little information is available about molecular mechanisms that contribute...

  14. Colored Mulches Affect Yield of Fresh-market Tomato Infected with Meloidogyne incognita

    OpenAIRE

    Fortnum, B. A.; Decoteau, D. R.; Kasperbauer, M. J.

    1997-01-01

    The effects of different-colored polyethylene mulches on the quantity and spectra of reflected light, earliness of fruit set, fruit yield and quality, and root-knot disease were studied in field-grown, staked tomato (Lycopersicon esculentum). White mulch reflected more photosynthetic light and a lower far-red-to-red ratio than red mulch, whereas black mulch reflected less than 5 percent of any color. Soil temperatures and fruit yields were recorded for tomato plants inoculated with Meloidogyn...

  15. Caracterização genética e molecular de acessos de bananeira a Radopholus similis e Meloidogyne incognita

    OpenAIRE

    Santos, Jansen Rodrigo Pereira

    2011-01-01

    A cultura da bananeira tem grande importância econômica e social em todo o mundo. O Brasil é o quarto produtor mundial de banana, sendo esta cultivada de Norte a Sul do País e, praticamente toda produção é comercializada no mercado interno. Problemas fitossanitários de variadas etiologias reduzem a vida útil dos plantios e levam a perdas na produção e na qualidade dos frutos. Dentre os fitonematoides, Radopholus similis, Meloidogyne incognita, M. javanica, M. arenaria, Helicotylenchus multici...

  16. Integrated application of some compatible biocontrol agents along with mustard oil seed cake and furadan on Meloidogyne incognita infecting tomato plants

    Institute of Scientific and Technical Information of China (English)

    GOSWAMI Bijoy Kumar; PANDEY Rajesh Kumar; RATHOUR Kabindra Singh; BHATTACHARYA Chaitali; SINGH Lokendra

    2006-01-01

    Experiments were carried out to study the effect of two fungal bioagents along with mustard oil cake and furadan against root knot nematode Meloidogyne incognita infecting tomato under greenhouse condition. Bioagents viz., Paecilomyces lilacinus and Trichoderma viride alone or in combination with mustard cake and furadan promoted plant growth, reduced number of galls/plant, egg masses/root system and eggs/egg mass. The fungal bioagents along with mustard cake and nematicide showed least nematodes reproduction factor as compared to untreated infested soil.

  17. Use of microbial and chemical agents to control Meloidogyne incognita in soybean - doi: 10.4025/actasciagron.v32i3.2166

    OpenAIRE

    Henrique Teixeira Nunes; Antonio Carlos Monteiro; Alan William Vilela Pomela

    2010-01-01

    Nematoides de galhas constituem importante grupo de patógenos da cultura da soja e o manejo integrado é uma das principais medidas de controle que visam à redução de perdas econômicas. Neste trabalho foi avaliada a eficácia dos fungos Paecilomyces lilacinus (Thom.) Samsom e Pochonia chlamydosporia (Goddard) Zare & Gams (sinonímia Verticillium chlamydosporium), de um produto comercial à base de Bacillus sp. (Nemix) e do nematicida químico Aldicarb no controle de Meloidogyne incognita em soja, ...

  18. Nematicidal Activity of Kojic Acid Produced by Aspergillus oryzae against Meloidogyne incognita.

    Science.gov (United States)

    Kim, Tae Yoon; Jang, Ja Yeong; Jeon, Sun Jeong; Lee, Hye Won; Bae, Chang-Hwan; Yeo, Joo Hong; Lee, Hyang Burm; Kim, In Seon; Park, Hae Woong; Kim, Jin-Cheol

    2016-08-28

    The fungal strain EML-DML3PNa1 isolated from leaf of white dogwood (Cornus alba L.) showed strong nematicidal activity with juvenile mortality of 87.6% at a concentration of 20% fermentation broth filtrate at 3 days after treatment. The active fungal strain was identified as Aspergillus oryzae, which belongs to section Flavi, based on the morphological characteristics and sequence analysis of the ITS rDNA, calmodulin (CaM), and β-tubulin (BenA) genes. The strain reduced the pH value to 5.62 after 7 days of incubation. Organic acid analysis revealed the presence of citric acid (515.0 mg/kg), malic acid (506.6 mg/kg), and fumaric acid (21.7 mg/kg). The three organic acids showed moderate nematicidal activities, but the mixture of citric acid, malic acid, and fumaric acid did not exhibit the full nematicidal activity of the culture filtrate of EML- DML3PNa1. Bioassay-guided fractionation coupled with (1)H- and (13)C-NMR and EI-MS analyses led to identification of kojic acid as the major nematicidal metabolite. Kojic acid exhibited dose-dependent mortality and inhibited the hatchability of M. incognita, showing EC50 values of 195.2 µg/ml and 238.3 µg/ml, respectively, at 72 h postexposure. These results suggest that A. oryzae EML-DML3PNa1 and kojic acid have potential as a biological control agent against M. incognita.

  19. 有机酸类化合物对南方根结线虫的生物活性%Bioactivity of organic acids against Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    刘丹丹; 段玉玺; 陈立杰; 曲泽兰; 罗璇; 刘大伟

    2011-01-01

    采用室内离体测定方法,测试了15种有机酸对南方根结线虫(Meloidogyne incognita)2龄幼虫致死率和卵孵化抑制率.结果表明,甲酸和丙酸对2龄幼虫和卵的生物活性最高,明显优于其他供试有机酸,但是活性低于对照药剂阿维菌素.对生物活性结果及有机酸化学结构进行比对发现,小分子童化合物对南方根结线虫具有较高生物活性.%Fifteen organic acids from commercial sources were assayed against Meloidogyne incognita to compare their nematicidal activity. The LC50 parameter was applied to evaluate their nematicidal activity. The present study showed that formic acid and propanoic acid had the highest corrected mortality and incubation inhibition ratio, but the bioactivity of abamectin was better than that of formic acid and propanoic acid. Through analyzing compound structure and its bioactivity, we found that the compounds with small molecular volume had more excellent activity than the others.

  20. Analysis of Gene expression in soybean (Glycine max roots in response to the root knot nematode Meloidogyne incognita using microarrays and KEGG pathways

    Directory of Open Access Journals (Sweden)

    Gamal El-Din Abd El Kader Y

    2011-05-01

    Full Text Available Abstract Background Root-knot nematodes are sedentary endoparasites that can infect more than 3000 plant species. Root-knot nematodes cause an estimated $100 billion annual loss worldwide. For successful establishment of the root-knot nematode in its host plant, it causes dramatic morphological and physiological changes in plant cells. The expression of some plant genes is altered by the nematode as it establishes its feeding site. Results We examined the expression of soybean (Glycine max genes in galls formed in roots by the root-knot nematode, Meloidogyne incognita, 12 days and 10 weeks after infection to understand the effects of infection of roots by M. incognita. Gene expression was monitored using the Affymetrix Soybean GeneChip containing 37,500 G. max probe sets. Gene expression patterns were integrated with biochemical pathways from the Kyoto Encyclopedia of Genes and Genomes using PAICE software. Genes encoding enzymes involved in carbohydrate and cell wall metabolism, cell cycle control and plant defense were altered. Conclusions A number of different soybean genes were identified that were differentially expressed which provided insights into the interaction between M. incognita and soybean and into the formation and maintenance of giant cells. Some of these genes may be candidates for broadening plants resistance to root-knot nematode through over-expression or silencing and require further examination.

  1. Evaluation of biological nematicides on the control of root-knot nematode (Meloidogyne incognita Chitwood at protected crops house in tomato (Lycopersicon esculentum Mill.

    Directory of Open Access Journals (Sweden)

    Pedro Fidel Fuentes Chaviano

    2011-06-01

    Full Text Available This research was carried out on Tomato (Lycopersicon esculentum Mill. variety HA 3105 at the protected crops houses in Empresa Azucarera Melanio Hernández of Sancti Spiritus, located at the southwest of Tuinucú, from November 2009 to May 2010 with the objective of evaluating the effectiveness of biological nematicides on the control of the root-knot nematode, Meloidogyne incognita Chitwood. Three treatments were used: Agrocelhone, biological nematicide HeberNem and HeberNem + Trichoderma. Biological nematicides showed better results than Agrocelhone regarding the length of the leaf, the height of the plant, the yield of tomato and the control of nematodes HeberNem showed the best results in the control of the nematode, decreasing the infestation from degree V to degree II.

  2. Studies on the management of root-knot nematode, Meloidogyne incognita-wilt fungus, Fusarium oxysporum disease complex of green gram, Vigna radiata cv ML-1108

    Institute of Scientific and Technical Information of China (English)

    HASEEB Akhtar; SHARMA Anita; SHUKLA Prabhat Kumar

    2005-01-01

    Studies were conducted under pot conditions to determine the comparative efficacy of carbofuran at 1 mg a.i./kg soil,bavistin at 1 mg a.i./kg soil, neem (Azadirachta indica) seed powder at 50 mg/kg soil, green mould (Trichoderma harzianum) at 50.0 ml/kg soil, rhizobacteria (Pseudomonas fluorescens) at 50.0 ml/kg soil against root-knot nematode, Meloidogyne incognita-wilt fungus, Fusarium oxysporum disease complex on green gram, Vigna radiata cv ML-1108. All the treatments significantly improved the growth of the plants as compared to untreated inoculated plants. Analysis of data showed that carbofuran and A. indica seed powder increased plant growth and yield significantly more in comparison to bavistin and P.fluorescens. Carbofuran was highly effective against nematode, bavistin against fungus, A. indica seed powder against both the pathogens and both the bioagents were moderately effective against both the pathogens.

  3. Impact of direct and indirect application of rising furfural concentrations on viability, infectivity and reproduction of the root-knot nematode, Meloidogyne incognita in Pisum sativum.

    Science.gov (United States)

    Abdelnabby, Hazem; Wang, Yunhe; Xiao, Xueqiong; Wang, Gaofeng; Yang, Fan; Xiao, Yannong

    2016-07-01

    The gradual withdraw of several broadly used nematicides from market has enhanced the need to develop sustainable and eco-friendly alternatives with nematicidal properties. Furfural is one of the promising alternatives to fill this need. Baseline information about the impact of furfural on egg hatch, penetration potential and ultrastructure of nematode is lacking. In this study, the reagent-grade (purity ≥ 99.0%) of furfural was applied against Meloidogyne incognita. In vitro tests showed gradual reduction in either the rate of egg hatch or second stage juvenile (J2) viability of M. incognita when immersed in concentrations ranging from 0 to 10.0 μl/ml furfural. The mean EC50 for J2 and egg hatch was 0.37 and 0.27 μl/ml furfural, respectively. Furfural, even at low concentrations, resulted in a considerable suppression in egg hatch. Hatch was 0.2 ml/kg soil. No adverse effect was detected on plants or free-living nematodes as a result of furfural application. Liquid furfural proved to have superior juvenile-suppressive effect whereas its vapor has such superiority against eggs. Scanning electron microscope (SEM) study showed irregular appearance of the body surface accompanied with some cuticle disfigurement of furfural-treated juveniles. These results indicated that furfural can adversely affect egg hatch, juvenile viability, penetration potential and ultrastructure of M. incognita. Furfural may therefore be of a considerable potential as an appropriate alternative for class I nematicides.

  4. Influence of plant species on the biological control activity of the antagonistic rhizobacterium Rhizobium etli strain G12 toward the root-knot nematode, Meloidogyne incognita.

    Science.gov (United States)

    Mahdy, M; Hallmann, J; Sikora, R A

    2001-01-01

    The influence of plant species on the antagonistic activity of the rhizosphere bacterium Rhizobium etli G12 towards the root-knot nematode Meloidogyne incognita was studied. The crops tested were tomato, cucumber, cotton, soybean and pepper. The plants were evaluated for the following parameters: root gall-index, total number of galls and egg masses of M. incognita, as well as shoot and root fresh weight and root length. Results indicated a clear influence of plant species on the ability of R. etli G12 to reduce nematode infection. Based on the root gall index, nematode control by R. etli G12 was higher on vegetables (tomato, cucumber, pepper) than on field crops (soybean, cotton). Reduction in galling ranged from 17% for cotton to 50% for tomato. R. etli G12 also reduced the actual number of galls produced. The reduction in the number of galls produced between crops was not affected significantly as was seen when a galling index was used to measure activity. The reduction in the number of galls was similar in level for all the crops studied and ranged from 34% for cucumber to 47% for tomato. There was a significant reduction in the number of egg masses produced by the females ranging from 37% for soybean to 70% for pepper. This indicated a direct effect on female development in the root after penetration or delayed penetration on certain crops. The bacteria caused significant increases in shoot fresh weight from 11% for soybean to 31% for pepper and in root fresh weight from 3% for soybean to 39% for tomato and in root length from 11% for cucumber to 24% for pepper. R. etli G12 gave significant control of M. incognita on a broad range of host plants, but the level of control varied. The suitability of each plant species, therefore, must be examined before R. etli G12 can be recommend for control of this nematode.

  5. IDENTIFICACIÓN MORFOLÓGICA, MORFOMÉTRICA Y MOLECULAR DE Meloidogyne incognita EN HIGUERA (Ficus carica L. EN COSTA RICA

    Directory of Open Access Journals (Sweden)

    Walter Peraza-Padilla

    2013-01-01

    Full Text Available El objetivo de este estudio fue identificar la especie de Meloidogyne asociada a dos plantaciones de higuera en Costa Rica. En marzo de 2012, en el distrito de Pacayas, provincia de Cartago, se detectaron agallas en los sistemas radicales de plantas de higuera (Ficus carica L. de dos fincas. De las raíces agalladas se extrajeron hembras, masas de huevos y juveniles (J2 de Meloidogyne sp. Se examinaron los patrones perineales de las hembras y los segundos estadios infectivos se analizaron morfológica y molecularmente mediante PCR-RFLP. Se amplificó la región intergénica (IGS del genoma mitocondrial, delimitada por el gen de la subunidad II de la citocromo oxidasa (COII y el gen ribosomal 16S. La población de nematodos se identificó como M. incognita. El tamaño de los productos de PCR generados con los imprimadores C2F3 y 1108 fue de 1,7 kb. Al tratar los productos de PCR con enzimas de restricción, se generaron cuatro fragmentos de 850, 450, 250 y 150 pb con la enzima AluI y dos fragmentos de 1300 y 400 pb con la enzima HinfI.

  6. Inconsistency of the biological control of Meloidogyne incognita race 2 in melon by endophytic bacteria Inconsistência do controle biológico de Meloidogyne incognita raça 2 em meloeiro por bactérias endofíticas

    Directory of Open Access Journals (Sweden)

    Jeane E de Medeiros

    2009-09-01

    Full Text Available We obtained 61 rhizobacterium isolates from rhizosphere soil samples collected in melon commercial fields located in Mossoró, Rio Grande do Norte State, Brazil. These isolates, along with 56 endophytic bacteria from the Collection of Cultures of the Plant Bacteriology Laboratory of the Universidade Federal Rural de Pernambuco, were tested for controlling Meloidogyne incognita race 2 in melon. To infest the soil with nematodes, 1000 eggs of Meloidogyne incognita race 2 per plant were placed in pots where seedlings of the yellow-type melon, cultivar AF 682, were growing for 10 days. Two days before, 20 mL of bacterial suspension (0.7 OD570nm were poured into each pot. After 60 days, fresh root biomass, gall index, egg mass, and the nematode reproduction factor were assessed. Among the 117 isolates screened, the endophytic Bacillus ENM7, ENM10, and ENM51 were selected because they significantly reduced egg mass and/or gall index. However, when tested again, separately and in mixtures, these isolates nor confirmed their efficiency in vivo, neither affected juvenile emergence in vitro. These results give evidence on the inconsistency of using endophytic-bacteria in the control of M. incognita race 2 in melon.A partir de amostras de solo coletadas em plantios comerciais de meloeiro, situados em Mossoró-RN, foram obtidos 61 isolados de rizobactérias que, juntamente com outros 56 isolados endofíticos pertencentes à Coleção de Culturas do Laboratório de Fitobacteriologia da Universidade Federal Rural de Pernambuco, foram avaliados para o controle de Meloidogyne incognita raça 2 em melão. Plantas de meloeiro Amarelo, cultivar AF 682, com dez dias de idade tiveram o solo infestado com 1000 ovos de M. incognita raça 2 por planta. Dois dias antes, foram depositados em cada vaso 20 mL da suspensão bacteriana (DO570nm = 0,7. Decorridos 60 dias, foram determinados a biomassa fresca das raízes, os índices de galhas e de massa de ovos e o fator de

  7. 蓖麻提取物对南方根结线虫的防治作用%Control effects of Ricinus communis extracts on Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    高倩圆; 胡飞龙; 祝红红; 刘满强; 李辉信; 胡锋

    2011-01-01

    通过毒力测定及盆栽试验,研究了蓖麻提取物对南方根结线虫的杀线活性及防治效果.结果表明:蓖麻碱及蓖麻水提液均具有较强毒杀线虫活性,蓖麻碱浓度为2g·L-1、处理48 h杀线虫活性最强,线虫校正死亡率达91.5%,LC50为0.6 g·L-1;蓖麻水提液浓度为100g·L-1、处理48 h杀线虫活性最强,线虫校正死亡率达83.5%,LC50为18.3 g·L-1;蓖麻碱、蓖麻水提液和蓖麻叶植物粉处理接种南方根结线虫的番茄苗后,植株平均根结数分别为(17.6±1.7)、(20.6±1.5)和(22.8±3.7),均显著低于对照(37.4±2.3),根长分别比对照提高46.8%、34.5%和33.8%,株高分别比对照提高33.5%、22.6%和15.8%,植株鲜质量分别比对照增加41.4%、18.9%和10.1%.蓖麻提取物能减轻线虫危害,对盆栽番茄南方根结线虫病控制效果明显.%Toxicity test and pot experiment were conducted to study the nematocidal activity and control effects of Ricinus communis extracts on Meloidogyne incognita. The results showed that both the ricinine and the R. Communis water extracts had high nematocidal activity. The ricinine at concentration 2 g · L-1 and treated for 48 hours had the strongest nematocidal activity, leading to 91. 5% of corrected mortality of M. Incognita and with the LC50 being 0.6 g · L-1, whereas the R. Communis water extracts at concentration 100 g · L-1 and treated for 48 hours had the strongest nematocidal activity, which led to 83.5% of corrected mortality of M. Incognita, and the LC50 was 18.3 g · L-1. With the inoculation of M. Incognita treated with ricinine, R. Communis water extracts , and R. Communis leaf powder, respectively, on tomato seedlings, the mean number of plant root-knots was 17.6±1.7, 20.6±1.5 and 22.8±3.7, respectively, being significantly lower than the control (37.4±2.3), and the root length increased by 46.8% , 34.5% and 33. 8% , and the plant height increased by 33.5% , 22.6% and 15.8% , and the

  8. Eficiência e atividade enzimática elicitada por metil jasmonato e silicato de potássio em cana-de-açúcar parasitada por Meloidogyne incognita Efficiency and enzymatic activity elicited by methyl jasmonate and potassium silicate on sugarcane under Meloidogyne incognita parasitism

    Directory of Open Access Journals (Sweden)

    Lílian Margarete Paes Guimarães

    2010-03-01

    Full Text Available O presente estudo teve como objetivo avaliar o efeito de metil jasmonato e silicato de potássio sobre o parasitismo de Meloidogyne incognita na variedade RB863129 de cana-de-açúcar (Saccharum sp. e a atividade enzimática da peroxidase e β-1,3-glucanase elicitada, em condições de casa de vegetação. Metil jasmonato diminuiu significativamente o número de ovos por grama de raiz, mas não afetou à biomassa da parte aérea da planta. Sete dias após a aplicação, os dois indutores afetaram a atividade de β-glucanase na plantas parasitadas e, aos 14 e 21 dias, promoveram variações significativas nos níveis de peroxidase e β-1,3-glucanase, muito embora, ao contrário da peroxidase, a atividade β-1,3-glucanase não diferiu entre plantas inoculadas e não inoculadas.The present study had as objective to evaluate methyl jasmonate and potassium silicate effect on Meloidogyne incognita parasitism in sugarcane (Saccharum sp. variety RB863129 and peroxidase and β-1,3-glucanase activity elicited, under greenhouse. The effect of Methyl jasmonate and potassium silicate did not affect shoot biomass. Methyl jasmonate and potassium silicate significantly decreased eggs number per gram of roots. Seven days after application, both inducers affected b-glucanase activity in parasited plants and at 14 and 21 days, inducers promoted significant variations in peroxidase e -1,3-glucanase levels in plants under parasitism, although, inversely to peroxidase, β-1,3-glucanase activity did not differ between inoculated and non inoculated plants.

  9. The Infection of Cucumber (Cucumis sativus L.) Roots by Meloidogyne incognita Alters the Expression of Actin-Depolymerizing Factor (ADF) Genes, Particularly in Association with Giant Cell Formation

    Science.gov (United States)

    Liu, Bin; Liu, Xingwang; Liu, Ying; Xue, Shudan; Cai, Yanling; Yang, Sen; Dong, Mingming; Zhang, Yaqi; Liu, Huiling; Zhao, Binyu; Qi, Changhong; Zhu, Ning; Ren, Huazhong

    2016-01-01

    Cucumber (Cucumis sativus L.) is threatened by substantial yield losses due to the south root-knot nematode (Meloidogyne incognita). However, understanding of the molecular mechanisms underlying the process of nematode infection is still limited. In this study, we found that M. incognita infection affected the structure of cells in cucumber roots and treatment of the cytoskeleton inhibitor (cytochalasin D) reduced root-knot nematode (RKN) parasitism. It is known that Actin-Depolymerizing Factor (ADF) affects cell structure, as well as the organization of the cytoskeleton. To address the hypothesis that nematode-induced abnormal cell structures and cytoskeletal rearrangements might be mediated by the ADF genes, we identified and characterized eight cucumber ADF (CsADF) genes. Phylogenetic analysis showed that the cucumber ADF gene family is grouped into four ancient subclasses. Expression analysis revealed that CsADF1, CsADF2-1, CsADF2-2, CsADF2-3 (Subclass I), and CsADF6 (Subclass III) have higher transcript levels than CsADF7-1, CsADF7-2 (Subclass II genes), and CsADF5 (Subclass IV) in roots. Members of subclass I genes (CsADF1, CsADF2-1, CsADF2-2, and CsADF2-3), with the exception of CsADF2-1, exhibited a induction of expression in roots 14 days after their inoculation (DAI) with nematodes. However, the expression of subclass II genes (CsADF7-1 and CsADF7-2) showed no significant change after inoculation. The transcript levels of CsADF6 (Subclass III) showed a specific induction at 21 DAI, while CsADF5 (Subclass IV) was weakly expressed in roots, but was strongly up-regulated as early as 7 DAI. In addition, treatment of roots with cytochalasin D caused an approximately 2-fold down-regulation of the CsADF genes in the treated plants. These results suggest that CsADF gene mediated actin dynamics are associated with structural changes in roots as a consequence of M. incognita infection. PMID:27695469

  10. The Infection of Cucumber (Cucumis sativus L. Roots by Meloidogyne incognita Alters the Expression of Actin-Depolymerizing Factor (ADF Genes, Particularly in Association with Giant Cell Formation

    Directory of Open Access Journals (Sweden)

    Bin Liu

    2016-09-01

    Full Text Available Cucumber (Cucumis sativus L. is threatened by substantial yield losses due to the south root-knot nematode (Meloidogyne incognita. However, understanding of the molecular mechanisms underlying the process of nematode infection is still limited. In this study, we found that M. incognita infection affected the structure of cells in cucumber roots and treatment of the cytoskeleton inhibitor (cytochalasin D reduced root-knot nematode (RKN parasitism. It is known that Actin-Depolymerizing Factor (ADF affects cell structure, as well as the organization of the cytoskeleton. To address the hypothesis that nematode-induced abnormal cell structures and cytoskeletal rearrangements might be mediated by the ADF genes, we identified and characterized eight cucumber ADF (CsADF genes. Phylogenetic analysis showed that the cucumber ADF gene family is grouped into four ancient subclasses. Expression analysis revealed that CsADF1, CsADF2-1, CsADF2-2, CsADF2-3 (Subclass I and CsADF6 (Subclass III have higher transcript levels than CsADF7-1, CsADF7-2 (Subclass II genes and CsADF5 (Subclass IV in roots. Members of subclass I genes (CsADF1, CsADF2-1, CsADF2-2 and CsADF2-3, with the exception of CsADF2-1, exhibited a induction of expression in roots 14 days after their inoculation (DAI with nematodes. However, the expression of subclass II genes (CsADF7-1 and CsADF7-2 showed no significant change after inoculation. The transcript levels of CsADF6 (Subclass III showed a specific induction at 21 DAI, while CsADF5 (Subclass IV was weakly expressed in roots, but was strongly up-regulated as early as 7 DAI. In addition, treatment of roots with cytochalasin D caused an approximately two-fold down-regulation of the CsADF genes in the treated plants. These results suggest that CsADF gene mediated actin dynamics are associated with structural changes in roots as a consequence of M. incognita infection.

  11. Description of Meloidogyne incognita from Yantai,Shandong Province of China%采自烟台市的南方根结线虫的描述

    Institute of Scientific and Technical Information of China (English)

    赵洪海; 梁晨; 刘维志; 段玉玺; 刘晔

    2000-01-01

    在烟台市西沙旺苗圃内的剑麻Agave rigida上发现一种根结线虫,经鉴定为南方根结线虫Meloidogyne incognita.该种根结线虫的主要鉴定特征为雌虫口针的基部球横向宽,背食道腺开口到口针基部球的距离近,会阴花纹多数呈六边形,背弓中等到高,多为方形,背线平滑或稍有波浪,侧线不明显.雄虫头冠前缘稍有凹陷,口针基球横向宽,前缘平或向后斜,与基杆界限明显,背食道腺开口距口针基球的距离很短.二龄幼虫直肠有的膨大明显,但在大多数标本中看不到膨大,尾透明末端界限明显或不太明显,指状,末端钝圆.与南方根结线虫的典型群体相比,该群体的雌虫和雄虫的口针都偏小.

  12. Reaction of vegetables and aromatic plants to Meloidogyne javanica and M. incognita Reação de hortaliças e plantas aromáticas aos nematoides Meloidogyne javanica e M. incognita

    Directory of Open Access Journals (Sweden)

    Cláudia Regina Dias-Arieira

    2012-06-01

    Full Text Available For this research we used 15 day-old seedlings which were transplanted to 2 L pots and inoculated with 4,000 nematode eggs plus juveniles (J2. After 60 days, the root systems were removed and the number of galls and eggs evaluated and used to calculate the nematode reproduction factor (RF. The tomato cv. Santa Cruz was used as a susceptible control. The experimental design was completely randomized, with six replications. Averages were compared using the Tukey or Scott-Knott test at 5%. For lettuce, Salad Bowl (Mimosa type, Elizabeth and Elisa (Lisa and Vera cultivars (crisphead, the number of galls and the RF for M. javanica were statistically higher than for the control, whereas, for the other vegetable crops, the highest number of galls and eggs were found in chicory and basil. The highest susceptibility to M. incognita was observed in Mimosa lettuce cv. Salad Bowl, chicory cultivars, parsley cv. Graúda Portuguesa and basil. Marjoram exhibited no M. incognita galls.Para avaliar a reação, mudas com 15 dias de idade foram transplantadas para vasos de 2 L de capacidade e inoculadas com 4.000 ovos e eventuais juvenis (J2 dos nematoides. Decorridos 60 dias, os sistemas radiculares foram retirados e avaliados quanto ao número de galhas e ovos, determinando-se o fator de reprodução (FR dos nematoides nas respectivas plantas. Tomateiro cv. Santa Cruz foi utilizado como testemunha. O experimento foi conduzido em delineamento inteiramente casualizado, com seis repetições, e as médias foram comparadas pelo teste Tukey ou Scott-Knott a 5% de probabilidade. Nas alfaces tipo Mimosa cv. Salad Bowl; nas cultivares do tipo Lisa, Elizabeth e Elisa; e na cultivar Vera (tipo crespa, o número de galhas e o FR de M. javanica foi superior ao observado para a testemunha; enquanto para as demais oleráceas, os maiores números de galhas e ovos foram para as cultivares de chicória e para o manjericão. Maior suscetibilidade a M. incognita foi observada para

  13. Nematicidal Activity ofAbutilon theophrasti Medic Crude Extracts against Meloidogyne Incognita%苘麻提取物对南方根结线虫的活性

    Institute of Scientific and Technical Information of China (English)

    谢宁; 苏秀荣; 王金信

    2011-01-01

    [Methods]To find environment-friendly nomaticide against Meloidogyne incognita.The nematicidal activity of the extracts with different solvents from A butilon theophrasti were determined against M.Incosnita.The extract with methanol was prel im inarily separated to get the crude alkaloid.The alkal ine water layer which had strongest nematicidal activity was further exuacted by 12 different solvents in increasing order of polarity,and the ncmaticidal activity of the 12 extraction components were investigated.[Results] Among 12 extraction components,A 5 extracted by a mixture of chloroform and methanol(4:1,by vol)and A8(1:2,by vol)had strong nematocidal activity.Treating M.incognita with extracts,A 5 showed 100%control(48 h afber treatment)at 125g/L and A8 exhibited 93.2%control.[Conclusions]A 5 and A8 can be further pudfied and traced tO be bioassayed.%[方法]为寻找环境友好型杀线虫剂,测定了不同溶剂苘麻提取物对南方根结线虫的生物活性,对甲醇提取物进行生物碱粗分离,并对杀线虫活性强的碱水层进一步用极性从小到大的溶剂萃取,同时进行生物活性检测.[结果]12个萃取组分中氯仿与甲醇体积比为4∶1(A5)和1∶2(A8)两组分具有极强杀线虫活性,干粉质量浓度125g/L时,A5组分48h的线虫校正死亡率达100%,A8组分达932%.[结论]可对A5和A8组分进一步分离纯化和生物活性追踪.

  14. Interactions between fodder radish and tagetes varieties and Meloidogyne hapla populations

    NARCIS (Netherlands)

    Lammers, J.

    2013-01-01

    In this study, resistance to Meloidogyne hapla populations is the focal point. It involves a screening of fodder radish and Tagetes varieties with a number of local M. hapla populations to determine their infection rate.

  15. Controlling effects of Ricinus communis extracts and Paecilomyces lilacinus against Meloidogyne incognita%蓖麻提取物和淡紫拟青霉对南方根结线虫的防治作用

    Institute of Scientific and Technical Information of China (English)

    高倩圆; 胡飞龙; 祝红红; 杜志敏; 刘满强; 李辉信; 胡锋

    2011-01-01

    A bioassay and a pot experiment were conducted to study the nematocidal activities and the controlling effects of Ricinus communis extracts and Paecilomyces lilacinus against Meloid-ogyne incognita. It was observed that ricinine had no impact on the germination of P. Lilacinus spores, whereas both ricinine and P. Lilacinus had strong nematocidal activities. In treatment ricinine, the inhibition rate of egg-hatching and the mortality of the second stage juveniles of M. Incognita were 61. 7% and 59. 2% , respectively, being significantly higher than those in control treatment. In treatment ricinine plus P. Lilacinus, the mean number of the root-knots per plant of tomato seedlings inoculated with M. Incognita was 15 ±3, which was significantly lower than that (37±2) in the control, and the plant height, fresh mass, and root length of the seedlings were increased by 38. 5% , 44. 0% , and 57.0% , respectively, as compared to the control.-The results suggested that R. Communis extracts and P. Lilacinus could mitigate the harm of M. Incognita, and also, have obvious effects in controlling M. Incognita.%通过杀线活性测定及盆栽试验,研究了蓖麻提取物和淡紫拟青霉(Paecilomyces lilacinus)对南方根结线虫(Meloidogyne incognita)的杀线活性及防治效果.结果表明:蓖麻碱不影响淡紫拟青霉孢子的萌发.蓖麻碱和淡紫拟青霉均具有较强杀线活性,蓖麻碱处理对南方根结线虫的卵孵化抑制率和二龄幼虫死亡率分别达61.7%和59.2%,显著高于对照处理;蓖麻碱和孢子液复合处理接种南方根结线虫的番茄苗后,植株平均根结数为15±3,显著低于对照的平均根结数37±2,株高、鲜重和根长增长率分别比对照提高38.5%、44.0%和57.0%.说明蓖麻提取物和淡紫拟青霉能减轻线虫危害,对番茄南方根结线虫病控制效果明显.

  16. Evaluation of in vitro and in vivo nematicidal potential of a multifunctional streptomycete, Streptomyces hydrogenans strain DH16 against Meloidogyne incognita.

    Science.gov (United States)

    Kaur, Talwinder; Jasrotia, Shivam; Ohri, Puja; Manhas, Rajesh Kumari

    2016-11-01

    The present work demonstrated the nematicidal potential of Streptomyces hydrogenans strain DH16 (a strain with strong antagonism against fungal phytopathogens and insect pest) against Meloidogyne incognita. The culture supernatant and solvent extract significantly inhibited egg hatching (almost 100%) along with J2 mortality of more than 95% after 96h. The nematicidal activity of 10-(2,2-dimethyl-cyclohexyl)-6,9-dihydroxy-4,9-dimethyl-dec-2-enoic acid methyl ester (SH2; a new antifungal compound) purified from this streptomycete was also evaluated using different concentrations. The juvenile mortality of the nematode increased with increasing concentration and exposure time and reached the maximum (95%) after 96h at concentration of 100μg/ml. After 160h of incubation, egg hatch of 16% was observed at concentration of 100μg/ml as compared to control where 100% egg hatching was achieved. However, at the highest concentration of the compound (200μg/ml), 100% J2 mortality and 0% egg hatching were observed after 72 and 160h of incubation, respectively. In vivo pot experiments further revealed the nematicidal potential of S. hydrogenans where soil drenching with its culture supernatant and cells effectively controlled root galls, egg masses in nematode infested tomato plants and at the same time promoted the growth of tomato plants. Additionally, in the absence of nematodes, soil drenching with culture supernatant and cells significantly enhanced the various agronomic traits of plants as compared to control plants. Thus, the outcomes of the current study endorse the potential of S. hydrogenans strain DH16 and its metabolites to be developed as safe nematicidal and plant growth promoting agents.

  17. Biological Activity of Four Nematicides on Meloidogyne incognita%4种杀线虫剂对南方根结线虫的室内活性测定

    Institute of Scientific and Technical Information of China (English)

    张俊龙; 罗艳梅

    2016-01-01

    通过藏红T染色法,确定线虫染色时间,并测定4种常规药剂对南方根结线虫的室内活性.结果显示,染色1 h后,线虫的染色率达到100%.1.8%阿维菌素EC和40%灭线磷EC对南方根结线虫具有良好的活性,LC50值分别为14.9263 mg/L和15.3068 mg/L;40%辛硫磷EC和200 g/L丁硫克百威EC活性较差.%Laboratory experiment was conducted with four selected nematicides forMeloidogyneincognita, the dying time and toxic activity were determined by Safranine-T staining method. The results showed that the staining rate of Safranine-T reached 100%. Abamectin 1.8% EC and ethoprophos 40% EC had higher biological activities onMeloidogyne incognita, with LC50 values of 14.9263 mg/L and 15.3068 mg/L. Phoxim 40% EC and carbosulfan 200 g/L EC had less activities on Meloidogyne incognita.

  18. Greenhouse Evaluation of Selected Soybean Germplasm for Resistance to North Carolina Populations of Heterodera glycines, Rotylenchulus reniformis, and Meloidogyne Species.

    Science.gov (United States)

    Davis, E L; Koenning, S R; Burton, J W; Barker, K R

    1996-12-01

    Selected soybean genotypes were evaluated for resistance to North Carolina populations of the soybean cyst nematode Heterodera glycines, the root-knot nematodes Meloidogyne incognita races 3 and 4, M. arenaria races 1 and 2, M. javanica, and the reniform nematode Rotylenchulus reniformis in two greenhouse tests. Populations of cyst nematode used in the first test were cultures from field samples originally classified as races 1-5, and those used in the second test included inbred cyst lines that corresponded to races 1, 3, and 4. The original race classification of some cyst populations shifted after repeated culture on susceptible 'Lee 68' soybean. Most of the cyst-resistant soybean cultivars tested were susceptible to M. arenaria and M. javanica. Exceptionally large galls were induced by M. arenaria on roots of Asgrow 5979, Hartwig, and CNS soybean. Hartwig soybean and PI 437654 were resistant to all cultured field populations of cyst nematodes in a first greenhouse test. In the second test, cyst indices of 11.3% and 19.4% were observed on roots of PI 437654 and Hartwig, respectively, when infected with an inbred line (OP50) of H. glycines corresponding to race 4. The cyst-resistant soybean germplasm tested, including Hartwig and PI 437654, supported only low numbers of reniform nematodes. The most severe soybean root necrosis observed, however, was associated with reniform nematode infection.

  19. Identification of Resistance and Mi-1 Gene of Tomato Cultivars to Meloidogyne incognita%番茄种质材料对南方根结线虫的抗性鉴定及Mi-1基因检测

    Institute of Scientific and Technical Information of China (English)

    陆秀红; 黄金玲; 刘志明; 秦碧霞; 万宇力

    2013-01-01

    采用盆栽接种2龄幼虫法,对6份番茄Solanum lycopersicum种质材料进行了对南方根结线虫Meloidogyne incognita的抗性鉴定.结果表明:供试的番茄材料对南方根结线虫的抗性存在差异,其中,高抗材料4份,抗病材料1份,感病材料1份;采用酶切扩增多态性序列(Cleaved amplified polymorphic sequences,CAPS)方法对番茄抗性材料进行Mi-1基因检测,发现TY52、T27和Bss368 3份材料不合Mi-1基因,无限生长(红色)和T24含有Mi-1基因.%Using the pot inoculation of 2 instar larvae method, the resistance against Meloidogyne incognita in 6 Solarium lycopersicum tomato cultivar materials was evaluated. Results showed that there were significant differences between the resistance qualities in the 6 cultivars, out of which 4 were of high resistance, 1 was of normal resistance, and 1 was of susceptible quality to Meloidogyne incognita. Using the cleaved amplified polymorphic sequences (CAPS) method, the Mi-1 gene in tomato resistant material was detected, and found that three materials, TY52, T27, and Bss368, did not contain the Mi-1 gene while indeterminate growth (red) and T24 contain the Mi-1 gene.

  20. 生防茵K-8对南方根结线虫的防治及其鉴定%The Identification of Biocontrol Bacterium K-8 and Its Biological Control Against Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    梁建根; 郑经武; 郝中娜; 王连平; 陶荣祥; 张昕

    2011-01-01

    为了明确生防菌株K-8对南方根结线虫的防效及其分类地位,采用亚甲基蓝染色法测定了生防菌株K-8的发酵液对南方根结线虫2龄幼虫存活的影响,考察了其对南方根结线虫的防效,对其鉴定采用生理生化法、表型培养观察法、脂肪酸分析并结合16S rDNA序列分析法.结果表明,击倒试验发现,生防菌株K-8发酵液对南方根结线虫2龄幼虫有一定的杀伤作用,其矫正死亡率为70.8%,与化学药剂200 g/L克线丹的69.4%将近.菌株K-8对南方根结线虫温室盆栽防治效果为47.8%,明显高于对照200 g/L克线丹的防效41.3%.菌株K-8的形态与生理生化特性与巨大芽孢杆菌很接近,根据SI值和差值,脂肪分析把其鉴定为Bacillus megatenum,由16S rDNA序列分析的系统发育树发现,菌株K-8的序列与Bacillus megaterium构成1个分支,进化上的距离最近,由此可将其鉴定为巨大芽孢杆菌Bacillus megaterium.综合3种鉴定方法,最后把菌株鉴定为巨大芽孢杆菌Bacillus megaterium.%In order to evaluate classification status of biocontrol K-8 and its control efficacy to Meloidogyne incognita, using methylene blue staining method, death efficacy of biocontrol strain K-8 to Meloidogyne incogita was determined, its control efficacy to Meloidogyne incognita was studied by pot tests, and its identification was launched by means of phenotypic characteristics observation, physiological and biochemical indexes determination, FAME identity and the assay of 16S rDNA sequences. The results showed that the fermentation broth of strain K-8 showed a better killing effect on second stage juvennil Meloidogyne incognita and its correct death rate was 70.8%, which was close to that of 69.4% of 200 g/L cadusafos, pot trials of strain K-8 indicated that it had a better control efficacy to Meloidogyne incognita and was 47.8%, significantly better than that of 41.3% of 200 g/L cadusafos. According to the similarity index (SI

  1. 南方根结线虫拮抗放线菌的分离、鉴定与杀线虫活性分析%Isolation,Indentification and Evaluation for Nematicidal Activity of Actinomycetes Against Plant Nematode Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    陈井生; 朱峰; 鲁旭鹏; 刘大伟; 刘德福; 段玉玺; 陈立杰

    2015-01-01

    采用稀释分离法从连作大豆根际土壤中分离到1株放线菌H-2,对其进行了形态学特征、培养特征、生理生化特征鉴定及16S rDNA分析,初步鉴定H-2菌株为小链霉菌(Streptomyces parvus)。离体生物测定了小链霉菌H-2菌株发酵培养滤液对南方根结线虫和小杆线虫的生物活性。结果表明:H-2菌具有较高的选择性杀线虫活性,对南方根结线虫2龄幼虫及其卵囊的孵化具有较好的抑制作用,对土壤中自由生活的小杆线虫毒性微弱;H-2菌株代谢物5倍液处理24 h后,对南方根结线虫2龄幼虫的致死率达74.35%,卵囊孵化抑制率为78.46%,H-2菌株具有较高应用价值。%A strain H-2 was isolated by diluted solution method from soybean continuous cropping soil sample,its morphological,physiological and biochemical characteristics were identified and 16S rDNA was analyzed. The result showed that it was Streptomyces parvus. Fermentation filtrates of Streptomyces parvus at different concentrations were evaluated for nematicidal activity against Meloidogyne incognita and Rhabditis sp. in laboratory. Fermentation filtrates of the strains could suppress the egg hatching and 2nd-instar larvae of Meloido-gyne incognita. Culture filtrates of Strain H-2 showed a weak level of nematicidal activity of free-living Rhabditis sp. The corrected mortality rate of Meloidogyne incognita egg hatching and 2nd-instar larvae reached 74.35%and 78.46%,respectively by,strain H-2 at 5 diluted solution.

  2. 6种植物源化合物对南方根结线虫的毒性和温室防效研究%Nematicidal Activity of Six Phytochemicals against Meloidogyne incognita and Control Effects in Greenhouse

    Institute of Scientific and Technical Information of China (English)

    刘丹丹; 段玉玺; 陈立杰; 朱晓峰; 王媛媛

    2011-01-01

    采用室内离体测定和温室防效测定方法,研究6种植物源化合物对南方根结线虫(Meloido-gyne incognita)的防治作用.室内生物活性测定结果显示,草酸对南方根结线虫二龄幼虫的抑制作用最强,EC50=102.183 4 mg/L,6种化合物按抑制作用由大到小顺序为:草酸>巴豆酸>酒石酸>扁桃酸>苹果酸>柠檬酸.温室防效试验结果表明,6种化合物对南方根结线虫二龄幼虫的防效,仍以草酸最高(76.8%),柠檬酸最低(10.4%),顺序与室内生物活性测定结果一致.%The nematicidal activity and control effects of 6 phytochemicals against Meloidogyne incognita J2 were separately tested in glass culture dishes and greenhouse.The result showed that oxalic acid had the strongest inhibition activity,of which EC50 was 102.183 4mg/L.According to the inhibition activity,the order from big to small was oxalic acid>crotonic acid>tartaric acid> mandelic acid>malic acid>citric acid.The result in greenhouse indicated that the control effect of oxalic acid(76.8 %) was the most significant and citric acid the lowest(10.4%).And the control effect order of 6 chemicals against M.incognita in greenhouse was consistent with that of their nematicidal activity.

  3. Differential Sensitivity of Meloidogyne spp. and Heterodera glycines to Selected Nematicides.

    Science.gov (United States)

    Gourd, T R; Schmitt, D P; Barker, K R

    1993-12-01

    Differential sensitivity of Meloidogyne arenaria, M. hapla, M. incognita, M. javanica, and Heterodera glycines races 1 and 5 to the nonfumigant nematicides aldicarb, ethoprop, and fenamiphos was evaluated using a 48-hour root-penetration bioassay. Generally, H. glycines was more tolerant of the nematicides, especially ethoprop, than were the Meloidogyne species. Among Meloidogyne species, M. incognita was most sensitive to aldicarb and fenamiphos, but its reaction to ethoprop was similar to the other three Meloidogyne species.

  4. Efecto del filtrado crudo de Purpureocillium sp. (Cepa UdeA0106, sobre la eclosión de huevos y movilidad de juveniles de Meloidogyne incognita-javanica

    Directory of Open Access Journals (Sweden)

    Nadya Lorena Cardona Bustos; M.Sc., Ph.D.

    2014-12-01

    Full Text Available Meloidogyne incognita-javanica represents an important threat to the agricultural crops, and it is necessary to seek alternatives for its control. The aim of this research it was to evaluate a crude filtrate from the strain Purpureocillium sp. UdeA0106 in order to establish the in vitro effect on the egg hatching and the immobility of juvenile stages of Meloidogyne spp. The mediums evaluated were malt extract broth (MEB, yeast extract broth (YEB, and potato dextrose broth (PDB, after which it was chosen the one that didn’t produce any damages on nematode eggs and allowed the emergence of the larval stages. The fungus was multiplied for 7 days, and then it was filtrated. To evaluate its effect on the eggs and the J2 of Meloidogyne spp., filtrate concentrations were made at 100 %, 90 %, 70 %, 50 %, 25 % and 10 %, contrasting them with a control composed of the J2 stages in sterile distilled water and PDB. The variables evaluated were the percentage of altered eggs and the immobility observed in J2 stages. The experimental unit was the Petri dish, each one containing 200 eggs /J2. Each treatment was replicated 5 times. It was used a completely randomized design, and an ANOVA was performed (P = 0,05 as well as a multiple comparison test (Tukey. Significant differences were found between all treatments (P < 0,05, although the most effective in inhibiting both egg hatching and J2 mobility (96,8 % were the full strength filtering (100 %. The dilutions at 90 % and 70 %, were able to produce effects with high percentages in the immobility.

  5. Isolamento e avaliação da atividade nematicida de constituintes químicos de Mucuna cinerea contra Meloidogyne incognita e Heterodera glycines

    Directory of Open Access Journals (Sweden)

    Demuner Antonio Jacinto

    2003-01-01

    Full Text Available Phytochemical investigation of the aerial parts and roots of Mucuna cinerea led to the isolation of a mixture of fatty acids, triacylglicerols, beta-sitosterol, stigmasterol, stigmasterol glucoside, daucosterol, asperglaucide (4 and the isoflavonoids prunetin (1, genistein (2, medicarpin (3, daidzein (5, 7-O-alpha-glycopiranosyl daidzein (6. An in vitro bioassay was carried out with compounds 1-4, at the concentration of 50 and 5 mug mL-1 against the phytonematodes M. incognita and H. glycines. Although the four compounds showed some nematocidal property, the most active was (1, causing 70% mortality of M. incognita at the concentration of 50 mug mL-1.

  6. 臭氧水对南方根结线虫卵和幼虫的抑制效果研究%The Inhibitory Effects of Ozone Water on Eggs and Juveniles of Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    郭培强; 赵洪海; 丁建法; 陈优明; 李世祥

    2012-01-01

    利用臭氧水处理南方根结线虫2龄幼虫以及游离卵和卵囊,测试其对2龄幼虫的致死作用和对卵孵化的抑制作用,同时测定不同次数和不同浓度臭氧水处理对土壤内南方根结线虫2龄幼虫群体密度的影响.结果显示,各处理浓度臭氧水对2龄幼虫具有致死作用,在0.60mg/kg浓度处理下,对2龄幼虫的校正致死率达95.25%;当臭氧水浓度低于0.20mg/kg时,臭氧水对游离卵和卵囊内卵的孵化均表现出促进作用;当浓度高于0.50mg/kg时,臭氧水对线虫卵孵化表现出抑制作用;臭氧水能有效降低土壤中南方根结线虫2龄幼虫的群体密度.试验结果表明,臭氧水可作为一种潜在的杀线虫剂加以利用.%The second stage juveniles ( J2s), free eggs and egg masses of Meloidogyne incognita were treated in vitro with ozone water to detect its lethal effect on J2s and inhibitory efficacy on egg hatching, and the nematode -infected soils were treated with ozone water at different times and concentrations in pot experiment to test its impact on the population density of J2s. Hie results indicated that ozone water had lethal effect on J2s at every treating concentrations, and the corrected mortality of J2s measured up to 95.25% under the treating concentration of 0. 60mg/kg. Ozone water showed promoting effects on the hatching of free eggs and eggs in egg masses when the treating concentrations were below 0. 20mg/kg, and it exhibited inhibitory effect on the egg hatching when the treating concentrations were above 0. 50mg/kg. The pot experiment showed that ozone water could reduce the population density of J2s in soil. The trials in vitro and in pot demonstrated that ozone water could be exploited and utilized as one potential nematicide.

  7. Purification and identification of metabolites produced by Bacillus cereus and B. subtilis active against Meloidogyne exigua, and their in silico interaction with a putative phosphoribosyltransferase fromM. incognita

    Directory of Open Access Journals (Sweden)

    DENILSON F. OLIVEIRA

    2014-06-01

    Full Text Available To contribute to the development of products to controlMeloidogyne exigua, the bacteria Bacillus cereus and B. subtilis were cultivated in liquid medium to produce metabolites active against this plant-parasitic nematode. Fractionation of the crude dichloromethane extracts obtained from the cultures afforded uracil, 9H-purine and dihydrouracil. All compounds were active against M. exigua, the latter being the most efficient. This substance presented a LC50 of 204 µg/mL against the nematode, while a LC50 of 260 µg/mL was observed for the commercial nematicide carbofuran. A search for protein-ligand complexes in which the ligands were structurally similar to dihydrouracil resulted in the selection of phosphoribosyltransferases, the sequences of which were used in an in silico search in the genome of M. incognita for a similar sequence of amino acids. The resulting sequence was modelled and dihydrouracil and 9H-purine were inserted in the active site of this putative phosphoribosyltransferase resulting in protein-ligand complexes that underwent molecular dynamics simulations. Calculation of the binding free-energies of these complexes revealed that the dissociation constant of dihydrouracil and 9H-purine to this protein is around 8.3 x 10-7 and 1.6 x 10-6 M, respectively. Consequently, these substances and the putative phosphoribosyltransferase are promising for the development of new products to control M. exigua.

  8. Progress in The Biological Control of Root-knot Nematodes, Meloidogyne incognita%植物源提取物防治根结线虫的分子研究

    Institute of Scientific and Technical Information of China (English)

    秦燕

    2012-01-01

      This review focused on the recent findings concerning the biological control of root-knot nematodes,including the bio-control of Meloidogyne incognita by using antagonistic fungi, plant extracts and plant disease resistance genes. The review also provided an insight into the adaptation of nematode-parasitized immunocompetent plants, and provide the way for discovering new anti-parasitic strategies.%  针对内生真菌的生物防治,重点阐述了中草药提取物的杀虫活性、植物抗线虫基因的发现以及植物防御系统激发的最新研究。植物源提取物作为潜在的线虫杀虫剂,为生物源农药开发和利用提供新的思路。同时,对于今后线虫杀虫剂开发中存在的问题及解决方案进行了探讨,就其发展方向提出了建议。

  9. 温度和初始接种量对南方根结线虫侵染力的影响%Effects of temperature and initial inoculation density on root-knot nematode (Meloidogyne incognita) infection ability

    Institute of Scientific and Technical Information of China (English)

    张锋; 李英梅; 洪波; 张淑莲; 陈志杰

    2012-01-01

    The effects of temperature, host vegetables and initial inoculation density of root-knot nematode (Meloidogyne incognita) on root-knot nematode driven vegetable symptoms were investigated under greenhouse conditions. The results showed that the optimum temperature for root-knot nematode incidence from May to September was 22.17~27.61 °C, with obvious symptom detection in cucumber plants after three days. When temperature was 15.38-18.67 °C during January to April and October to December, obvious symptom detection in cucumber plants was after 15 days. Symptom appearance time was delayed and disease incidence inhibited. 15 different host plants were infected by the second-stage juveniles of M. incognita. Symptoms appeared in 10 days for watermelon, melon, bitter-gourd, cucumber, pumpkin, squash and green grocery. There were 5 days later for tomato, cowpea, eggplant cabbage and celery. Symptom appearance time in leek and welsh onion was the longest, without becoming obvious after 30 days. The infection ability of M. incognita varied significantly among the six vegetables (cucumber, tomato, eggplant, green grocery, leek and pepper). The numbers of second-stage M. incognita juveniles in rhizosphere soil and adult females and egg-masses in cucumber and tomato roots were more than those in eggplant, green grocery, leek and pepper. With initial inoculation density enhancement of second-stage juveniles, obvious symptoms appeared earlier in tomatoes with a more severe disease index. When inoculation density of second-stage M. incognita juveniles was 80100 g'(soil), obvious symptoms appeared in tomatoes after four days. At second-stage M. incognita juvenile inoculation rate of 160-100 g'(soil), it exceed saturation density thereby suppressing disease rate and index.%在棚室盆栽条件下,研究了南方根结线虫在不同温度、不同蔬菜寄主及不同初始接种密度下的症状表现.结果表明,5-9月,气温在22.17~27.61℃之间,南方

  10. Bioactivities of Ethanol Extracts from Leaves of Sapium sebiferum to Meloidogyne incognita%乌桕乙醇提取物对罗汉果根结线虫的生物活性初报

    Institute of Scientific and Technical Information of China (English)

    蒋妮; 高微微; 缪剑华

    2007-01-01

    为寻找高效低毒的防治罗汉果根结线虫(Meloidogyne incognita)的新途径,该文通过毒力测定及盆栽试验进行了乌桕[Sapium sebiferum(Linn.)Roxb.]叶乙醇提取物对罗汉果根结线虫的生物活性研究.结果表明乌桕叶乙醇提取物含具有较强毒杀线虫活性,浓度2.5g/L、处理48h活性最强,线虫校正死亡率达93.13%,LC50为333mg/L;乌桕叶乙醇提取物稀释100倍、1000倍、10000倍后处理接种了罗汉果根结线虫的番茄苗,植株平均根结数分别为12.5±3.84,20.17±4.01,31.8±5.09,均显著低于对照(5%乙醇水溶液)的平均根结数62.5±5.53,株高分别比对照提高28.10%、21.07%、12.23%,植株鲜重分别比对照增加33.07%、15.31%、2.73%.乌桕叶乙醇提取物能减轻线虫危害,促进植株生长,利用乌桕叶提取物防治根结线虫具深入研发的价值.

  11. 银胶菊叶和花提取物对南方根结线虫的毒杀活性比较%Comparison of nematicidal activity of extracts from leaf and flower of Parthenium hysterophorus against Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    苏秀荣; 谢宁; 张纪龙; 王金信

    2012-01-01

    为进一步明确银胶菊(Parthenium hysterophorus L.)的杀线虫活性,对银胶菊叶和花的不同溶剂提取物、甲醇提取物的不同萃取物以及甲醇提取物碱水层的不同极性组分对南方根结线虫(Meloidogyne incognita Chitwood)的杀虫活性进行了检测,并对不同提取物、萃取物和萃取组分进行了生物碱的定性分析.结果表明:银胶菊叶和花的蒸馏水、甲醇、乙酸乙酯和石油醚提取物的得率分别为24.5%和20.3%、19.6%和10.9%、6.8%和7.7%、2.0%和2.7%,其中,叶和花的蒸馏水和甲醇提取物的杀线虫活性均较强,而石油醚提取物的杀线虫活性最弱.用质量体积分数1.0%和0.5%的叶和花蒸馏水提取物分别处理24和48 h后试虫的校正死亡率均达到100.00%;用质量体积分数1.0%和0.5%的叶和花甲醇提取物处理48 h,试虫的校正死亡率均大于90%.叶和花甲醇提取物的碱水层、三氯甲烷Ⅰ层和Ⅱ层萃取物均具有一定的杀线虫活性,其中,用质量体积分数1.0%的花和叶碱水层萃取物以及花的三氯甲烷Ⅰ层萃取物分别处理48 h,试虫的校正死亡率均为100.00%,而三氯甲烷Ⅱ层萃取物的杀线虫活性最弱.银胶菊叶和花甲醇提取物碱水层的11个不同极性组分(A1~A11)也表现出不同程度的杀线虫活性,其中,用质量体积分数0.2%和0.1%花的A2[溶剂为V(三氯甲烷)∶V(甲醇)=10∶1]和A7[溶剂为V(三氯甲烷)∶v甲醇)=1∶1]组分以及叶的A2和A6[溶剂为V(三氯甲烷)∶V(甲醇)=2∶1]组分处理48 h后,试虫的校正死亡率均达100.00%,显著高于其他组分.定性实验结果表明:银胶菊叶和花中具有杀线虫活性的提取物、萃取物和萃取组分中均含有生物碱.研究结果说明:银胶菊花的杀线虫活性高于叶片,其毒杀活性不仅与提取部位及溶剂的种类和极性有关,还与提取物浓度及作用时间等因素有关.%In order to definite

  12. A New Tomato Hybrid 'Jinpeng M6' with Resistance to Meloidogyne incognita%抗南方根结线虫番茄新品种‘金棚M6’

    Institute of Scientific and Technical Information of China (English)

    李晓东; 郑丽芳; 王建人; 巩振辉; 蔡义勇; 李永宁; 任向辉

    2012-01-01

    ‘金棚M6’番茄是以‘M6’为母本,‘13B’为父本杂交培育的无限生长类型一代杂种。植株生长势较强,叶片较稀。果实高圆形,幼果无绿肩。成熟果粉红色,无棱沟,着色均匀一致,光泽度好。果肉厚,果实硬度好,耐贮耐运,货架期长。高抗南方根结线虫,高抗番茄花叶病毒(ToMV),中抗黄瓜花叶病毒(CMV),抗枯萎病和叶霉病。适宜日光温室、大棚等保护地春提早、越冬及秋冬春一大茬栽培。早熟,春提早种植前期产量可达52500kg·hm-2,春季栽培总产量一般为127500-150000kg·hm-2。%'Jinpeng M6' is a new indeterminate growth type and pink tomato hybrid, which is developed by crossing 'M6' x ' 13B' . The hybrid grows strongly and has spare foliage. Fruits are highly round in shape, and young fruits have no green shoulder. Its matured fruit is pink, has a smooth peel, uniform colour and high glossiness. The fruit has thick pulp, big fruit core, long storability and shelf-life. The hybrid is highly resistant to Meloidogyne incognita and ToMV, moderately resistant to CMV, fusarium wilt and leaf mould. It is suitable for cultivation in early spring, overwinter and one big crop of autumn-winter-spring under greenhouse conditions. It is early ripening, the early yield is 52 500 kg · hm-2 in early spring, the total yield is about 127 500 - 150 000 kg·hm-2 in spring.

  13. Preliminary study on nematicidal mechanism of secondary metabolites from Beauveria bassiana Snef23 to Meloidogyne incognita%球孢白僵菌次生代谢产物对南方根结线虫的作用机制初探

    Institute of Scientific and Technical Information of China (English)

    刘琼; 刘晓宇; 王媛媛; 朱晓峰; 段玉玺; 陈立杰

    2014-01-01

    为明确球孢白僵菌Beauveria bassiana对南方根结线虫Meloidogyne incognita的作用机理,从线虫的活动频率、呼吸强度、体液渗透压、总糖含量、可溶性蛋白含量以及乙酰胆碱酯酶( AChE )活性几方面测定了球孢白僵菌Snef23菌株次生代谢产物对南方根结线虫2龄幼虫( J2)的影响。结果表明:Snef23次生代谢产物可抑制南方根结线虫J2的活动频率和呼吸作用,降低其乙酰胆碱酯酶活性,增强虫体内容物的渗漏,干扰J2体内糖和可溶性蛋白的代谢,从而达到毒杀致死作用。研究结果为探明球孢白僵菌杀线虫的作用机制提供了理论依据,可为更好地利用球孢白僵菌及其他天然产物防控植物的线虫病害提供参考。%In order to understand the nematicidal mechanism of Beauveria bassiana against Meloidogyne incognita, the changes of physiological indexes of M. incognita second-stage juveniles (J2), including J2 locomotory behavior (mobile frequency), respiratory intensity, osmotic pressure of body fluid, total sugar content, soluble protein content and acetylcholinesterase activity etc, were detected after treatment with secondary metabolites of B. bassiana Snef23. The results showed that the secondary metabolites of B. bassiana Snef23 significantly reduced the mobile frequency and respiration intensity of M. incognita J2, inhibited the activity of acetylcholinesterase, increased the osmotic pressure of J2 body, interfered with the sugar and soluble protein metabolism of J2, which would lead to lethal effect on M. incognita. The results of present study provided theoretical data for elucidation of the nematicidal mechanism of B. bassiana Snef23, as well as for the prevention and control of plant nematode diseases by using B. bassiana and other nature productions in the future.

  14. Reprodução de Meloidogyne spp. em porta-enxertos e híbridos de pepino Reproduction of Meloidogyne spp. in rootstocks and cucumber hybrids

    Directory of Open Access Journals (Sweden)

    Silvia Renata S Wilcken

    2010-03-01

    Tetsukabuto' and 'Excite Ikki' and four cucumber (Cucumis sativus Japanese type hybrids of ('Yoshinari', 'Kouki', 'Taisho' and 'Tsuyataro'. Two experiments were carried out in greenhouse, each one with a nematode specie. Each plot consisted of one plant per pot containing 2 liters of autoclaved soil. Nine days after the seedlings transplantation, each plant was inoculated with 5,000 eggs and second-stage juveniles (initial population - Pi of M. javanica or M. incognita race 2. 'Rutgers' tomatoes were used as a standard for inoculum viability in both experiments. The experimental design was completely randomized with five replicates per treatment. Sixty days after inoculated, each plant was evaluated, when root fresh weight, total number of nematodes in the soil and in the roots (final population - Pf, nematodes number per gram of root and the reproduction factor of both Meloidogyne species (FR=Pf/Pi were determined. All rootstocks and cucumber hybrids allowed the M. javanica and M. incognita race 2 multiplication, but, generally, reproduction factor values were greater in cucumbers than in rootstocks.

  15. Native-plant hosts of Meloidogyne spp. from Western Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Vanessa A. Antes

    2012-04-01

    Full Text Available The present study was focused on the parasitism of Meloidogyne species on the roots of native nursery plants from the Atlantic forest. Native plants were selected from a commercial nursery in Western Paraná, searching for the natural infection of Meloidogyne. Also, the seeds of native plants were cultivated in sterile soil and inoculated with M. incognita. In both the experiments, the number of galls and number of eggs and J2 per root, allied to the reproduction factor of M. incognita on each inoculated plant were assessed. Natural infection by M. javanica was found on Cordia ecalyculata, Citharexyllum myrianthum and Aspidosperma subincanum and by M. incognita on Croton urucurana, Lonchocarpus muehlbergianus, Tabebuia impetiginosa and T. serratifolia. Meloidogyne incognita induced galls formation on Genipa americana, Schinus terebinthifolius and Rollinia mucosa after inoculation, which suggested that those plants could host this nematode in natural biomes. Nursery soil should be disinfested before seeding the native forest plants for reforestation purposes

  16. Effect of Pleurotus ostreatus on Dynamics of Meloidogyne arenaria Population and Control Effectiveness

    Institute of Scientific and Technical Information of China (English)

    XIANG Hong-qiong; FENG Zhi-xin

    2002-01-01

    The control effects and application methods of Pleurotus ostreatus on the peanut root-knot nematode disease, Meloidogyne arenaria, were systematically studied in the greenhouse. Results of pot experiments showed that P. Ostreatus could effectively reduce the 2nd-instar population density in the soil, and the larva reduced by 80% compared with the control. P. Ostreatus could markedly lower the infecting number of the peanut root-knot nematodes, the nematode density inside the root knots declined by 40.00% - 82.64%, and the peanut root knots also reduced by 86.96% - 94.03%. The fungus could defer the initial infection of M. Arenaria to the roots, the epidemic rate of the peanut root-knot nematode disease was significantly cut down, and the increase of root-knot changed from the way of Logistic curve in the control to the way of linear curve in the treatment. The final control effectiveness was about 80%. The results of pot trial also indicated that the control effectiveness is closely related to the application time and the amount of this fungus. The key factor affecting control effectiveness was the application time of P. Ostreatus in the soil and the suitable time was 20 days before sowing.

  17. 生防制剂与呋喃丹颗粒剂防治根结线虫幼虫的效果%Effect of bio-control agents and Furadon 3G on the juvenile mortality of root knot nematode Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    N.VijayaKumari; P.Sjathamma; 等

    2002-01-01

    印度南方根结线虫广泛地分布于印度南部灌溉桑园,特别是轻质土壤的桑园,它严重地影响桑叶的产量和质量.人们曾采用农业和化学等防治措施进行桑园线虫的防治,但效果并不理想.为此,考虑用生物防治方法来进行试验研究.本研究采用拟青霉和轮枝孢真菌两种生防制剂及化学杀线虫剂呋喃丹颗粒剂对线虫幼虫进行致死性试验,每种生物制剂滤液设置3个浓度,分别为100%,75% 和50%.结果发现,该两种真菌制剂在滤液浓度100%下72 h 后的杀虫率分别为73.55%和78.45%,两者无显著差异.虽然它们对幼虫的致死效果比化学杀线虫剂呋喃丹效果略微差些,但生物制剂对自然环境、人畜安全.因此,生物制剂有望成为更经济、更安全的杀线虫剂.%The root knot nematode Meloidogyne incognita is widely distributed in irrigated mulberry gardens of South India especially in light textured soils. It causes significant reduction in leaf yield and quality. Hence a number of control measures which include cultural, biological and chemical methods have been suggested to bring down the nematode population in mulberry gardens. However, since both cultural and chemical methods have some practical problems in implementation in addition to their advantages, an alternative method of nematode control by using bio-control agents is considered and was taken for study. In this study the bio-control agents namely Paecilomyces lilacinus and Verticillium chlamidosporium along with chemical nematicide Furadon 3G were taken. Culture filtrates of these two bio-control agents with 100%, 75% and 50% concentration were taken to find out the nematode juvenile mortality rate at different durations. The two bio-control agents, Paecilomyces lilacinus and Verticillium chlamidosporium have shown nematicidal effect of 73.55% and 78.45% at 100% concentration of culture filtrates after 72 h duration, through the difference between these two

  18. 南方根结线虫、香蕉穿孔线虫和尖孢镰刀菌4号生理小种对巴西蕉致病力的测定%Determination of virulence of Meloidogyne incognita, Radopholus similis and Fusarium oxysporum f.sp.cubense race 4 on banana

    Institute of Scientific and Technical Information of China (English)

    符美英; 肖彤斌; 吴凤芝; 曾向萍; 陈绵才

    2014-01-01

    通过室内盆栽接种测试的方法,测定南方根结线虫(Meloidogyne incognita)、香蕉穿孔线虫(Radopholus similis)和尖孢镰刀菌4号生理小种(Fusarium oxysporum f.sp.cubense race4)对巴西蕉的致病力.结果表明:3种病原微生物进行单独侵染和复合侵染均能抑制巴西蕉的生长,且复合侵染对巴西蕉的生长量影响更大;南方根结线虫单独侵染巴西蕉的根结指数要比复合侵染的高;香蕉穿孔线虫单独侵染巴西蕉的病情指数要比复合侵染的高;而尖孢镰刀菌4号生理小种与根结线虫和香蕉穿孔线虫同时侵染巴西蕉时香蕉枯萎病病情指数相对最高.

  19. Meloidogyne partityla on Pecan Isozyme Phenotypes and Other Host.

    Science.gov (United States)

    Starr, J L; Tomaszewski, E K; Mundo-Ocampo, M; Baldwin, J G

    1996-12-01

    Meloidogyne sp. from five pecan (Carya illinoensis) orchards in Texas were distinctive in host range and iszoyme profiles from common species of Meloidogyne but were morphologically congruent with Meloidogyne partityla Kleynhans, a species previously known only in South Africa. In addition to pecan, species of walnut (Juglans hindsii and J. regia) and hickory (C. ovata) also were hosts. No reproduction was observed on 15 other plant species from nine families, including several common hosts of other Meloidogyne spp. Three esterase phenotypes and two malate dehydrogenase phenotypes of M. partityla were identified by polyacrylamide gel electrophoresis. Each of these isozyme phenotypes was distinct from those of the more common species M. arenaria, M. hapla, M. incognita, and M. javanica.

  20. Biocontrol Effection of Genetically-modified Strains Derived from Bacillus subtilis 168 on Meloidogyne incognita%枯草芽胞杆菌168的遗传修饰菌株对番茄根结线虫病的生防作用

    Institute of Scientific and Technical Information of China (English)

    魏利辉; 周冬梅; 王云鹏; 郭坚华

    2011-01-01

    PopW from Ralstonia solanacearum is a member of the harpin protein family, eliciting hypersensitive cell death in non-host plants, inducing disease resistance in plants and enhancing plant growth. To achieve secretory expression of PopW protein in Bacillus subtilis, we constructed recombinant expression vector pHTPOW, which carried the p43 promoter, a signal peptide element of nprB, and the full length PopW gene. The expression of PopW in the genetically modified strains was confirmed by SDS-PAGE and Western bloting analysis. In vitro test showed that on the 24 and 48 h after treated with the genetically modified strain BsW, the J2 mortality rates of Meloidogyne incognita were 53.4% and 79.6%, respectively. In the green house trials, the number of eggs and galls reduced significantly 42-days after tomato (Lycopersicon esculentum) treatment with the transgenic strain BsW and the biocontrol efficacy reached 60.0%. The genetically-modified bacteria strain which enhances plant growth and inhibits nematodes activity offers a new promising perspective on the reasearch and development of new microbial pesticides.%PopW是来源于青枯病菌(Ralstonia solancearum)的一种harpin蛋白,具有诱导植物抗病性和促进植物生长的作用.构建了含有p43强启动子和nprB信号肽的PopW基因的表达载体pHTPOW,将表达载体pHTPOW转入枯草芽胞杆菌(Bacillus subtilis )168得到工程菌株BsW.SDS-PAGE和Western blot结果表明BsW能分泌PopW蛋白.在离体实验中,测试工程菌BsW对南方根结线虫(Meloidogyne incognita)二龄幼虫(J2)的致死作用,结果显示处理24和48 h后,J2死亡率分别为53.4%和79.6%;在温室实验中,施用工程菌BsW的菌悬液处理番茄(Lycopersicon esculentum)植株,6周后根系上的卵块和根结数目明显减少,防效达到60.0%.具有促生和抑制线虫作用基因工程菌的构建,为研究和开发新型微生物农药,提供了一个新的视角.

  1. 福建省部分地区蔬菜根结线虫病的病原种类鉴定%Identification of the root-knot nematode species and populations parasitized at vegetables in Fujian Province, China

    Institute of Scientific and Technical Information of China (English)

    黄斌锋; 陈绵才; 张绍升

    2011-01-01

    Sixteen samples of the vegetables root-knot nematode diseases were collected from four counties in Fujian Province, China. Meloidogyne incognita, M. javanica and M. arenaria were identified from the samples, M.incognita was the dominant species.The most populations were single species, only 31% samples were mixed populations with M. incognita and M. javanica, or M.incognita and M. arenaria in the fields.%从福建省4个市(县)蔬菜基地采集的蔬菜根结线虫病的16份样本中,鉴定出南方根结线虫(Meloidogyne incognita)、爪哇根结线虫(M.javanica)和花生根结线虫(M.arenaria)3个种,其中,南方根结线虫为优势种.田间根结线虫种群多数为单一种,31%的样品为2个种组成的混合种群,这些混合种群由南方根结线虫与爪哇根结线虫或南方根结线虫与花生根结线虫组成.

  2. Evaluation of Cover Crops with Potential for Use in Anaerobic Soil Disinfestation (ASD) for Susceptibility to Three Species of Meloidogyne.

    Science.gov (United States)

    Kokalis-Burelle, Nancy; Butler, David M; Rosskopf, Erin N

    2013-12-01

    Several cover crops with potential for use in tropical and subtropical regions were assessed for susceptibility to three common species of root-knot nematode, Meloidogyne arenaria, M. incognita, and M. javanica. Crops were selected based on potential use as organic amendments in anaerobic soil disinfestation (ASD) applications. Nematode juvenile (J2) numbers in soil and roots, egg production, and host plant root galling were evaluated on arugula (Eruca sativa, cv. Nemat), cowpea (Vigna unguiculata, cv. Iron & Clay), jack bean (Canavalia ensiformis, cv. Comum), two commercial mixtures of Indian mustard and white mustard (Brassica juncea & Sinapis alba, mixtures Caliente 61 and Caliente 99), pearl millet (Pennisetum glaucum, cv. Tifleaf III), sorghum-sudangrass hybrid (Sorghum bicolor × S. bicolor var. sudanense, cv. Sugar Grazer II), and three cultivars of sunflower (Helianthus annuus, cvs. 545A, Nusun 660CL, and Nusun 5672). Tomato (Solanum lycopersicum, cv. Rutgers) was included in all trials as a susceptible host to all three nematode species. The majority of cover crops tested were less susceptible than tomato to M. arenaria, with the exception of jack bean. Sunflower cv. Nusun 5672 had fewer M. arenaria J2 isolated from roots than the other sunflower cultivars, less galling than tomato, and fewer eggs than tomato and sunflower cv. 545A. Several cover crops did not support high populations of M. incognita in roots or exhibit significant galling, although high numbers of M. incognita J2 were isolated from the soil. Arugula, cowpea, and mustard mixture Caliente 99 did not support M. incognita in soil or roots. Jack bean and all three cultivars of sunflower were highly susceptible to M. javanica, and all sunflower cultivars had high numbers of eggs isolated from roots. Sunflower, jack bean, and both mustard mixtures exhibited significant galling in response to M. javanica. Arugula, cowpea, and sorghum-sudangrass consistently had low numbers of all three

  3. Population dynamics of plant nematodes in cultivated soil: effects of combinations of cropping systems and nematicides.

    Science.gov (United States)

    Murphy, W S; Brodie, B B; Good, J M

    1974-07-01

    The population density of Meloidogyne incognita was significantly reduced in land that was fallowed or cropped to crotalaria, marigold, bermudagrass, or bahiagrass. The rate of population decline caused by different cropping systems was influenced by initial population densities. Crotalaria, marigold, and bare fallow were about equally effective in reducing the density of M. incognita below dctectable lcvels, usually requiring 1-3 yr. Bahiagrass and bcrmudagrass required 4-5 yr or longer to reduce M. incognita below a detectable level. A high population density of Trichodorus christiei developed in land cropped 5 yr to bermudagrass, bahiagrass, okra, and marigold. Population densities of Pratylenchus brachyurus and Xiphinema americanum increased in land cropped to crotalaria or bermudagrass. Belonolabnus Iongicaudatus was detected only in land cropped to bermudagrass, The effectiveness of nematicides in reducing M. incognita infection was rclatcd to nematode population density resulting from 5 yr of different cropping systems. Treatment with aldicarb reduced M. incognita below detectable levels following all cropping systems; treatment with ethoprop following all cropping systems except okra, treatment wflh ethylene dibromide following bahiagrass or fallow; and treatment with DBCP only after 5 yr of fallow. Tomato transplant growth was affected .by both cropping systems and nematicide treatment. Transplants grown after crotalaria and bahiagrass were significantly larger than those grown after other crops. Also, treatment with aldicarb and ethoprop significantly increased transplant size.

  4. The effect of different initial densities of nematode (Meloidogyne javanica) on the build-up of Pasteuria penetrans population

    Institute of Scientific and Technical Information of China (English)

    DARBAN Daim Ali; PATHAN Mumtaz Ali; BHATTI Abdul Ghaffar; MAITELO Sultan Ahmed

    2005-01-01

    Pasteuria penetrans will build-up faster where there is a high initial nematode density and can suppress root-knot nematode populations in the roots of tomato plants. The effect of different initial densities of nematode (Meloidogyne javanica)(150, 750, 1500, 3000) and P. penetrans infected females (F1, F3) densities (F0=control and AC=absolute control without nematode or P. penetrans inoculum) on the build-up of Pasteuria population was investigated over four crop cycles. Two major points of interest were highlighted. First, that within a confined soil volume, densities of P. penetrans can increase >100 times within 2 or 3 crop cycles. Second, from a relatively small amount of spore inoculum, infection of the host is very high. There were more infected females in the higher P. penetrans doses. The root growth data confirms the greater number of females in the controls particularly at the higher inoculum densities in the third and fourth crops. P. penetrans generally caused the fresh root weights to be higher than those in the control. P. penetrans has shown greater reduction of egg masses per plant at most densities.The effects of different initial densities of M. javanica and P. penetrans on the development of the pest and parasite populations were monitored. And no attempt was made to return the P. penetrans spores to the pots after each crop so the build-up in actual numbers of infected females and spores under natural conditions may be underestimated.

  5. 淡紫紫孢菌YES和粉红螺旋聚孢霉67-1组合对黄瓜根结线虫病的防效评价%Efficacy of Combined Use of Purpureocillium lilacinum YES and Clonostachys rosea 67-1 in Suppressing Cucumber Root-knot Disease Caused by Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    张家家; 李世东; 郭荣君; 彭毅; 孙漫红; 缪作清

    2014-01-01

    为了提高生防菌的防病效果及其稳定性,本研究以黄瓜根结线虫病为靶标病害,对淡紫紫孢菌(原名为淡紫拟青霉)YES与粉红螺旋聚孢霉67-1混和使用的防病效果进行了评价。平板对峙实验表明两菌株相容性较好,在马铃薯和黄瓜根际分泌物培养基上无拮抗作用;通过测定两菌株对根结线虫的卵寄生性及其无菌发酵滤液对2龄幼虫致死作用,确定YES菌株孢子悬浮液(2×106孢子/mL)对根结线虫的卵寄生作用(51.0%)显著高于菌株67-1(44.0%);而菌株67-1代谢产物48 h后对根结线虫2龄幼虫的致死率(100%)高于菌株YES(77.4%)。土壤中2龄幼虫接种量为1000线虫/100 g土时,将菌剂YES和67-1单独或混和加入育苗基质中(终浓度为106孢子/g基质)并在移栽时穴施50 g菌剂(106孢子/g),结果表明两菌株单独使用和混和使用的防治效果接近,在20%~30%左右;根据blissing independence模型,两菌株之间表现为拮抗作用。土壤中线虫卵密度为398卵/100 g干土时,菌剂YES和67-1混和使用可显著抑制黄瓜根系上根结的形成,防病效果为63.7%,显著高于两菌剂单独使用的防效33.0%和41.3%。两菌株之间表现为累加效应。上述结果表明,两个主要作用机理不同的生防菌混和使用可以延缓根结线虫的侵染,提高防病效果。但土壤中线虫虫态和密度影响依据blissing independence 模型判定生防菌之间的相容性。该结果对杀线虫复合生防菌剂的研制及使用技术改进具借鉴意义。%In order to improve the biocontrol efficacy of biological control agents (BCA), the authors used Purpureocillium lilacinum YES and Clonostachys rosea 67-1 in combination to control cucumber root-knot nematode caused by Meloidogyne incognita. Dual culture tests on plates of PDA and cucumber root extraction media demonstrated that the two fungi were non-antagonistic to

  6. 南方根结线虫伴生细菌宏基因组fosmid文库构建及其特征分析%Metagenomic fosmid library construction of Meloidogyne incognita associated bacteria and features analysis

    Institute of Scientific and Technical Information of China (English)

    张玉; 茆振川; 陈国华; 冯东昕; 谢丙炎

    2009-01-01

    为了研究南方根结线虫与伴生细菌的互作及其伴生细菌多样性,采用碘海醇介质离心技术、SDS裂解法和酚/氯仿抽提法等构建了南方根结线虫Meloidogyne incognita伴生细菌宏基因组fosmid文库,并进行文库特征分析.结果表明,该文库包含3万个克隆,插入片段大小分布在30~45kb之间,平均长度为40kb左右;共计包含1171 Mb DNA;质粒在fosmid传代中稳定遗传,没有发现插入片段的丢失或重排.末端测序结果显示,文库中南方根结线虫序列占2.04%,细菌序列占44.90%,无同源序列占53.06%;南方根结线虫伴生细菌优势种群为Sphingopyxis属和代尔夫特菌属Delftia.

  7. An early record of Meloidogyne fallax from Ireland

    Science.gov (United States)

    Topalović, Olivera; Moore, John F.; Janssen, Toon; Bert, Wim; Karssen, Gerrit

    2017-01-01

    Abstract Root-knot nematodes, Meloidogyne spp., cause huge economic losses worldwide. Currently, three Meloidogyne spp. are present on the quarantine A2 list of EPPO, Meloidogyne chitwoodi, Meloidogyne fallax and Meloidogyne enterolobii. As a quarantine organism, Meloidogyne fallax has been detected in England and Northern Ireland on sport turf in 2011, and in England on leek in 2013. However, its presence in Ireland has probably been overlooked since 1965, when Mr. John F. Moore and Dr. Mary T. Franklin had detected a new Meloidogyne species for that time. While the relevant data was recorded and a preliminary manuscript describing the species was prepared but never submitted for publication, and together with the original slides, pictures and drawings, it was restudied recently. We compared the population of Irish Meloidogyne sp. to other similar Meloidogyne spp. Careful observation and comparison shows that it belongs to Meloidogyne fallax. The characters found to be common for Irish Meloidogyne sp. and Meloidogyne fallax are female stylet length (14.6 μm) with oval to rounded basal knobs, oval shaped perineal pattern with moderately high dorsal arch, slender stylet in males (18.5 μm) with set off and rounded basal knobs, slightly set off male head with one post-labial annule and incomplete transverse incisures, and second-stage juveniles with large and rounded stylet basal knobs, and a gradually tapering tail (46.9 μm) with a broadly rounded tip and a clearly delimitated smooth hyaline part sometimes marked by constrictions (12.9 μm). The host test and gall formation also correspond to Meloidogyne fallax. The identification could not be additionally supported by molecular analysis, as we were unable to extract DNA from the old permanent slides. Nevertheless, our study reveals that the Meloidogyne species detected in Ireland in 1965 belongs to Meloidogyne fallax. PMID:28144174

  8. Analysis of 1,3-Dichloropropene for Control of Meloidogyne spp. in a Tobacco Pest Management System.

    Science.gov (United States)

    Fortnum, B A; Johnson, A W; Lewis, S A

    2001-12-01

    1,3-Dichloropropene (1,3-D) and nonfumigant nematicides were evaluated for control of Meloidogyne spp. and soil and foliar insects in a tobacco pest management system. In a field with a high Meloidogyne spp. population density (root gall index 4.0 to 4.5 on a 0 to 10 scale in untreated controls), tobacco yields and crop values increased (482 kg/ha and $1,784/ha for 1, 3-D; 326 kg/ha and $1,206/ha for fenamiphos; 252 kg/ha and $933/ha for ethoprop) with nematicide application over an untreated control. In fields with a low population density of Meloidogyne arenaria or M. incognita (root gall index 2.3 to 2.5 in untreated controls), yields ranged from 1,714 to 2,027 kg/ha and were not altered by fumigant or nonfumigant nematicide application. Carbofuran, a soil-applied nonfumigant nematicide/insecticide, reduced the number of foliar insecticide applications required to keep insect populations below treatment threshold (3.8 vs. 4.5, respectively, for treated vs. untreated). Carbofuran reduced the cost ($23/ha) of foliar insecticide treatments when compared to an untreated control. Although nonfumigant nematicides provided some soil and foliar insect control, the cost of using a fumigant plus a lower insecticidal rate of a soil insecticide/nematicide was comparable to the least expensive non-fumigant nematicide when the cost of foliar insecticide applications was included in the cost estimates. Savings in foliar insecticide cost by use of soil-applied nonfumigant nematicide/insecticides were small ($23/ha) in comparison to potential value reductions by root-knot nematodes when the nonfumigant nematicides fenamiphos or ethoprop ($578/ha and $851/ha, respectively) were used instead of 1,3-D.

  9. 黄瓜内生Ch1001菌株种子处理防治根结线虫的施用剂量研究%Optimization of Seed Treatment Dose of the Cucumber Endophytic Chaetomium Ch1001 Strain for Biological Control of Root Knot Nematode Meloidogyne incognita

    Institute of Scientific and Technical Information of China (English)

    鄢小宁; 杨艳; 贺春萍; 郑经武

    2011-01-01

    The cucumber endophytic Chaetomium strain Ch1001 has shown its ability to suppress root knot nematode, Meloidogyne incognita, when applied as seed treatment. However, its optimum application dose, which is an important parameter for practical use in order to obtain robust seedlings as well satisfied nematode control efficacy has not been determined. In this paper, the root viability, defense related enzymes activity as well root knot nematode control efficacy were tested after cucumber seeds were inoculated with Ch1001 at 1×103, 1×104, 1×105,1×106, 1×107, 1×108ascospores/seed respectively at sowing. Results indicated that root viability was not influenced by Ch1001 when the inoculum dose was at or lower than 1×105 ascospores/seed,but increased significantly at the inoculum dose of 1×106 and 1×107 ascospores/seed, and decreased dramatically at 1×108 ascospores/seed. PAL and chitinase activity did not enhance after Ch1001 treatment, POD and CAT activity significantly increased at 1×105, 1×10' and 1×107 ascospores/seed, indicating that Ch1001 induced resistance related to active oxygen metabolism. The root knot nematode M. incognita control efficacy was positively correlated to seed treatment dose, the galls formation was significantly inhibited at 1×104,1×105,1×106 and 1×107 ascospores/seed treatment, the satisfied inhibition reached at 1×106 and 1×107 ascopores/seed treatment, which were 45.3% and 57.0% respectively. Based on the above results, the dose at 1 ×107 ascospores/seed was optimum for practical use because of the enhanced root viability, defense related enzymes activity as well as the lowest nematode invasion.%内生毛壳菌Ch1001菌株种子处理对黄瓜幼苗上发生的根结线虫有防效.为培育壮苗并达到理想的防效,合适的施用剂量是实际应用所需的一个重要参数.笔者在黄瓜播种时分别用1×103、1×104、1 ×105、1× 106、1×107、1×108个孢子/种子的剂量处理种子,测定幼苗的

  10. Efeito de isolados de Paecilomyces lilacinus no desenvolvimento de cafezais e na população de Meloidogyne paranaensis Effect of isolates of Paecilomyces lilacinus on the development of coffee plantations and on the population of Meloidogyne paranaensis

    Directory of Open Access Journals (Sweden)

    Marina Capparelli Cadioli

    2009-06-01

    control with the fungus Paecilomyces lilacinus (Thom., 1910 Samson, 1974 stands out as an advantageous alternative of control, from the ecological or economy points of view. Thus, the objective of this work was to evaluate ten isolates of Paecilomyces lilacinus in the control of Meloidogyne paranaensis in coffee trees (Coffea arabica L. cv. Icatú, in greenhouse conditions. In the first experiment, the coffee seedlings were transplanted to substrate where tomato plants were previously cultivated, for M. paranaensis multiplication. The soil was mixed with 50 g rice colonized with ten isolates of P. lilacinus. In the second experiment, coffee seedlings were transplanted to substrate (1 sand: 1 dirt with 50 g rice colonized with the isolates of P. lilacinus. Then, the seedlings were inoculated with suspension of ±5000 eggs of M. paranaensis. In the two experiments, a new application was made with 50 g of the isolates after fifteen days. The design was completely randomized with twelve treatments and ten replicates. After 90 they days were evaluated. The isolated of P. lilacinus did not affect the diameter of the coffee stalk. In the first experiment, the isolates Pae 22, 24, and 28 promoted the growth of the seedlings, all of the isolates reduced the population of eggs in the root system, and the isolates Pae 3 and 12 reduced the population of J2 of M. paranaensis in the soil. In the second experiment, the isolates Pae 3, 10, 12, and 13 favored the growth of the plants but reduced the weight of the fresh roots, all of the isolates reduced the population of J2 in the soil, and the isolates Pae 3, 10, 13, 18, 22, and 24 reduced the malformations caused by M. paranaensis roots.

  11. Response of some common annual bedding plants to three species of meloidogyne.

    Science.gov (United States)

    McSorley, R; Frederick, J J

    1994-12-01

    Twelve ornamental bedding plant cultivars were grown in soil infested with isolates of Meloidogyne incognita race 1, M. javanica, or M. arenaria race 1 in a series of tests in containers in a growth room. Root galling (0-5 scale) and eggs/plant were evaluated 8-10 weeks after soil infestation and seedling transplantation. Snapdragon, Antirrhinum majus cv. First Ladies, was extensively galled and highly susceptible (mean gall rating >/=4.2 and >/=14,500 eggs/plant), and Celosia argentea cv. Century Mix and Coleus blumei cv. Rainbow were susceptible (>1,500 eggs/plant) to all three Meloidogyne isolates. Response of Petunia x hybrida varied with cultivar and nematode isolate. Little or no galling or egg production from any Meloidogyne isolate was observed on Ageratum houstonianum cv. Blue Mink, Lobularia maritima cv. Rosie O'Day, or Tagetes patula cv. Dwarf Primrose. Galling was slight (mean rating Salvia splendens cv. Bonfire, and Vinca rosea cv. Little Bright Eye. Verbena x hybrida cv. Florist was heavily infected (gall rating >4.0 and >/=7,900 eggs/plant) by M. javanica and M. arenaria but was nearly free of galling from M. incognita. Zinna elegans cv. Scarlet was nearly free of galling from M. incognita and M. arenaria but was susceptible (mean gall rating = 2.9; 3,400 eggs/plant) to M. javanica.

  12. Enhanced Synthesis of Antioxidant Enzymes, Defense Proteins and Leghemoglobin in Rhizobium-Free Cowpea Roots after Challenging with Meloydogine incognita

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    Jose T. A. Oliveira

    2014-11-01

    Full Text Available The root knot nematodes (RKN, Meloydogine spp., particularly Meloidogyne incognita and Meloidogyne javanica species, parasitize several plant species and are responsible for large annual yield losses all over the world. Only a few available chemical nematicides are still authorized for RKN control owing to environmental and health reasons. Thus, plant resistance is currently considered the method of choice for controlling RKN, and research performed on the molecular interactions between plants and nematodes to identify genes of interest is of paramount importance. The present work aimed to identify the differential accumulation of root proteins of a resistant cowpea genotype (CE-31 inoculated with M. incognita (Race 3 in comparison with mock-inoculated control, using 2D electrophoresis assay, mass spectrometry identification and gene expression analyses by RT-PCR. The results showed that at least 22 proteins were differentially represented in response to RKN challenge of cowpea roots mainly within 4–6 days after inoculation. Amongst the up-represented proteins were SOD, APX, PR-1, β-1,3-glucanase, chitinases, cysteine protease, secondary metabolism enzymes, key enzymes involved in ethylene biosynthesis, proteins involved in MAPK pathway signaling and, surprisingly, leghemoglobin in non-rhizobium-bacterized cowpea. These findings show that an important rearrangement in the resistant cowpea root proteome occurred following challenge with M. incognita.

  13. Effect of winter cover crops on nematode population levels in north Florida.

    Science.gov (United States)

    Wang, K-H; McSorley, R; Gallaher, R N

    2004-12-01

    Two experiments were conducted in north-central Florida to examine the effects of various winter cover crops on plant-parasitic nematode populations through time. In the first experiment, six winter cover crops were rotated with summer corn (Zea mays), arranged in a randomized complete block design. The cover crops evaluated were wheat (Triticum aestivum), rye (Secale cereale), oat (Avena sativa), lupine (Lupinus angustifolius), hairy vetch (Vicia villosa), and crimson clover (Trifolium incarnatum). At the end of the corn crop in year 1, population densities of Meloidogyne incognita were lowest on corn following rye or oat (P cover crops: soybean (Glycine max), cowpea (Vigna unguiculata), sorghum-sudangrass (Sorghum bicolor x S. sudanense), sunn hemp (Crotalaria juncea), and corn. Population densities of M. incognita and Helicotylenchus dihystera were affected by previous tropical cover crops (P winter cover crops present at the time of sampling. Plots planted to sunn hemp in the fall maintained the lowest M. incognita and H. dihystera numbers. Results suggest that winter cover crops tested did not suppress plant-parasitic nematodes effectively. Planting tropical cover crops such as sunn hemp after corn in a triple-cropping system with winter cover crops may provide more versatile nematode management strategies in northern Florida.

  14. Tourism Incognita: Experiencing the Liminal Edge of Destination Places

    OpenAIRE

    Lew, Alan A.

    2013-01-01

    In the age of European exploration, terra incognita referred to lands that were largely unknown to Europeans. In the world of contemporary tourism, tourism incognita refers to the lands and experiences that are largely unknown to the global mass tourism industry (tourism cognita). Tourism incognita includes specialty niche tourisms that operate on the edge and beyond of mass tourism, as well as the entire world of non-tourism places. Examples of tourism cognita and tourism incognita that are ...

  15. Susceptibilidad de genotipos de Solanum spp. al nematodo causante del nudo radical Meloidogyne spp. (chitwood) Susceptibility of genotypes of Solanum spp. to the nematode causative of the root knot Meloidogyne spp. (chitwood)

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    Cristian Gelpud Chaves

    2011-01-01

    Full Text Available El cultivo del lulo (Solanum quitoense L.) presenta una disminución en su productividad, debido al ataque de patógenos como el nematodo del nudo radical Meloidogyne spp., en el Departamento de Nariño (Colombia), se han reportado incidencias cercanas al 79%, y pérdidas del 50%. En la presente investigación, se colectaron 45 genotipos de (Solanum quitoense L.) en los Departamentos de Nariño y Putumayo y 4 genotipos silvestres (S. mammosum, S. hirtum, S. marginatum y S. umbellatum) buscando fuentes de resistencia al nematodo. Se inocularon 9 plantas de cada genotipo de dos meses de edad con 10000 huevos de Meloidogyne spp., dejando tres testigos por cada material. Las variables evaluadas fueron: altura de planta, severidad, incidencia, peso fresco (tallo y raíz) y especies prevalentes de Meloidogyne spp. Se hizo una clasificación de genotipos mediante escala de resistencia y regresión entre la severidad y las demás variables para establecer el efecto de Meloidogyne spp. sobre los genotipos de planta. Los resultados mostraron 100% de incidencia del nematodo en todos los genotipos, 2.04% genotipos resistentes, 34.7% moderadamente resistentes, 42.8% moderadamente susceptibles, 18.3% susceptibles, y 2.04% altamente susceptibles. El genotipo SQbr05 resistente, no se vio afectado por la severidad, al contrario SQbc04 genotipo susceptible, mostró reducciones significativas en peso fresco de tallo y raíz, (R² = 0.71 y 0.98), el genotipo silvestre (S. mammosum) es altamente susceptible, Meloidogyne incognita presentó 55.31% de presencia. El genotipo SQbr05 es promisorio para ser evaluado en campo.The green orange (Solanum quitoense L.) crop has decreased in its productivity due to the pathogens attack such as the root knot nematode Meloidogyne spp. In the Nariño Department of Colombia, pest incidences near to 79% and losses of 50% have been reported. In this study, 45 genotypes of Solanum quitoense were collected in Nariño and Putumayo

  16. DNA Isolation and GC Base Composition of Four Root-knot Nematode (Meloidogyne spp.) Genomes.

    Science.gov (United States)

    Pableo, E C; Triantaphyllou, A C; Kloos, W E

    1988-01-01

    Phenol extraction and cesium trifluoroacetate ultracentrifugation were compared for efficiency in the extraction of DNA from eggs and second-stage juveniles of four species of Meloidogyne. The second method proved to be more satisfactory in that it yielded larger amounts of DNA, shortened the extraction period, and reduced sample handling by eliminating phenol and ether extraction and RNAse treatment. It also made possible the extraction of DNA: from more than one sample at a time. The mean base compositions (% GC) of the total DNA of M. incognita, M. javanica, M. arenaria, and M. hapla, as determined by thermal denaturation tests, were quite similar, as they ranged only between 31 and 33%. Similarly, the thermal stability of the DNA of all four species covered a narrow range from 82.97 to 83.63 C.

  17. Nematode population densities and yield of sweet potato and onion as affected by nematicides and time of application.

    Science.gov (United States)

    Hall, M R; Johnson, A W; Smittle, D A

    1988-10-01

    Nematode population densities and yield of sweet potato and onion as affected by nematicides and time of application were determined in a 3-year test. Population densities of Meloidogyne incognita race 1 in untreated plots of sweet potato increased each year, but Helicotylenchus dihystera and Criconemella ornata did not. Ethoprop (6.8 kg a.i./ha) incorporated broadcast in the top 15-cm soil layer each spring before planting sweet potato reduced population densities of nematodes in the soil and increased marketable yield in 1982, but not in 1983 and 1984. When DD, fenamiphos, and aldicarb were applied just before planting either sweet potato or onion, nematode population densities at harvest were lower in treated than in untreated plots. No additional benefits resulted when the nematicides were applied immediately before planting both sweet potato and onion. Correlation coefficients (P incognita juveniles in the soil at harvest among years ranged from r = -0.33 to r = -0.54 and r = 0.31 to r = 0.54 (P incognita juveniles and H. dihystera in the soil at harvest were r = -0.42 and r = -0.31 (P

  18. Identification of Meloidogyne species associated with upland ornamentals plants in Costa Rica.

    Directory of Open Access Journals (Sweden)

    Stefany Solano-González

    2015-06-01

    Full Text Available The objective of this study was to identify nematodes species of the genus Meloidogyne associated with upland ornamental plants. We sampled ten ornamental species in a commercial nursery in San Isidro, Heredia, Costa Rica between 2011-2012. Morphometric measurements of the stylet length, the tail length, and the hyaline region of J2s, as well as perineal patterns of egg-carrying females were used for identification, Genomic DNA was extracted from single J2s and molecular analyses were performed by amplifying the intergenic region between cytochrome oxidase subunit II of the COII and the long subunit of the ARN ribosomal genes by PCR-RFLP. Combining these methods allowed identification of five species of nematodes of the genus Meloidogyne (M. arenaria, M. hapla, M. hispanica, M. incognita and M. javanica, and new restriction enzyme patterns were reported for M. hapla and M. javanica using AluI. Additionally, a preliminary report of M. hispanica was described by sequencing the 28S and 18S regions.

  19. Susceptibilidad de genotipos de Solanum spp. al nematodo causante del nudo radical Meloidogyne spp. (chitwood

    Directory of Open Access Journals (Sweden)

    Gelpud Chaves Cristian

    2011-03-01

    Full Text Available

    El cultivo del lulo (Solanum quitoense L. presenta una disminución en su productividad, debido al ataque de patógenos como el nematodo del nudo radical Meloidogyne  spp., en el Departamento  de Nariño (Colombia, se han reportado incidencias cercanas al 79%, y pérdidas del 50%.   En la presente investigación, se colectaron 45 genotipos de (Solanum quitoense  L. en los Departamentos  de Nariño  y Putumayo  y 4 genotipos  silvestres  (S. mammosum, S. hirtum,       S. marginatum  y S. umbellatum buscando fuentes de resistencia al nematodo. Se inocularon 9 plantas de cada genotipo de dos meses de edad con 10000 huevos de Meloidogyne spp., dejando tres testigos por cada material. Las variables evaluadas fueron: altura de planta, severidad, incidencia, peso fresco (tallo y raíz y especies prevalentes de Meloidogyne spp. Se hizo una clasificación de genotipos mediante escala de resistencia y regresión entre la severidad y las demás variables para establecer el efecto de Meloidogyne spp. sobre los genotipos de planta. Los resultados mostraron 100% de incidencia del nematodo en  todos  los  genotipos,  2.04%  genotipos  resistentes,  34.7%  moderadamente  resistentes, 42.8% moderadamente susceptibles, 18.3% susceptibles, y 2.04% altamente susceptibles. El genotipo SQbr05 resistente, no se vio afectado por la severidad, al contrario SQbc04 genotipo susceptible, mostró reducciones significativas en peso fresco de tallo y raIz, (R2 = 0.71 y 0.98,el genotipo silvestre (S. mammosum es altamente susceptible, Meloidogyne incognita presentó 55.31% de presencia. El genotipo SQbr05 es promisorio para ser evaluado en campo.

  20. Glomus intraradices para el control de Meloidogyne incognita (Kofoid & White) Chitwood en condiciones protegidas

    OpenAIRE

    Jairo Cristóbal Alejo; Elizabeth Herrera-Parra; Vicente Reyes Oregel; Esaú Ruiz Sánchez; José María Tun Suárez; Teresita Celis Rodríguez

    2010-01-01

    Se evaluó el efecto de la aplicación del hongo micorrízico arbuscular Glomus intraradices en plantas de tomate (Lycopersicon esculentum Mill.) cv. Maya. Las variables de reproducción del nematodo estimadas fueron número de agallas por planta_1 (NA), número de hembras por g_1de raíz teñida (NHE) y número de huevos por g_1 de raíz licuada (NHU). Para las plantas, las variables agronómicas de vigor consideradas correspondieron a altura de planta (AP), peso de fruto (PF), peso de raíz (PR), volum...

  1. Effects of Anaerobically Digested Slurry on Meloidogyne incognita and Pratylenchus penetrans in Tomato and Radish Production

    Directory of Open Access Journals (Sweden)

    Yu Yu Min

    2011-01-01

    Full Text Available Since effective disposable way of anaerobically digested biogas slurry is expected, ADS was applied to soil to evaluate its effects on nematode damage. Damage index of tomato by root-knot nematode was significantly (<.05 lower and the growth better in pots applied with ADS (100 and 200 mg NH+4-N kg−1 than that in those with chemical fertilizer and control (no ADS. ADS was applied into radish cultivated fields infested with the root-lesion nematode: a single (100 kg NH+4-N ha−1 in 2007 and 2008 and multiple applications (25, 50, 25 kg NH+4-N ha−1 soil in 2009. Damage to radish was 30% and 50% lower in ADS-treated fields than that in the control in 2007 and 2009, respectively, although not in 2008. These results suggest that application of ADS to fields might be feasible for mitigating nematode damage, but the rate and timing should be considered further for the best application way.

  2. Effects of metabolites of Gliocladium Roseum on egg hatch and juvenile mortality of Meloidogyne incognita

    Science.gov (United States)

    Root-knot disease caused by root-knot nematode is a serious yield limiting factor for several economically important crops including soybean, vegetables, fruit trees, tea, tobacco, and medicinal plants. Control of nematode is currently mostly limited to application of soil nematicides, which are cos...

  3. Grafting for Management of Southern Root-knot Nematode, Meloidogyne Incognita, in Watermelon

    Science.gov (United States)

    Four bottlegourd (Lagenaria siceraria) cultivars, one squash (Cucurbita moschata x C. maxima) hybrid, four wild watermelon (Citrullus lanatus var. citroides) germplasm lines, and one commercial wild watermelon (C. lanatus var. citroides) cultivar were evaluated as rootstocks for cultivated watermelo...

  4. Utility of Grafting for Managing Southern Root-knot Nematode, Meloidogyne Incognita, in Watermelon

    Science.gov (United States)

    Four bottlegourd (Lagenaria siceraria) cultivars, one squash (Cucurbita moschata x C. maxima) hybrid, four wild watermelon (Citrullus lanatus var. citroides) germplasm lines, and one commercial wild watermelon (C. lanatus var. citroides) cultivar were evaluated as rootstocks for cultivated watermelo...

  5. Resistência de porta-enxertos para pessegueiro e ameixeira aos nematóides causadores de galhas (Meloidogyne spp. Resistance of rootstock for peach tree and plum to root-knot nematodes (Meloidogyne spp.

    Directory of Open Access Journals (Sweden)

    José Carlos Fachinello

    2000-03-01

    Full Text Available O trabalho foi realizado com o objetivo de comparar o comportamento de cinco diferentes porta-enxertos para frutas de caroço em frente a duas espécies de nematóides do gênero Meloidogyne (Meloidogyne javanica e Meloidogyne incognita. O cultivar GF 677 foi obtido a partir do cultivo in vitro e os demais porta-enxertos a partir de sementes. Aos dois meses, as plântulas foram repicadas e inoculadas com uma mistura de Meloidogyne javanica e M. incognita aos 30, 60 e 70 dias após o plantio em canteiros incorporando-se 0,2kg de solo altamente infestado com os nematóides ao redor de cada planta. Ao final do experimento, avaliaram-se o desenvolvimento das plantas e o grau de infecção de cada cultivar. O grau de resistência dos cultivares foi estimado a partir do índice de galhas, obtido através de uma escala de grau ou nota, a qual varia de 0 a 5, em função do número de galhas ou ootecas. Os resultados obtidos demonstraram que o cultivar Okinawa não apresentou galhas no sistema radicular e na análise de crescimento foi superior aos demais cultivares. Os cultivares R-15-2 e Aldrighi foram considerados resistentes aos fitonematóides por apresentarem pequeno número de galhas no sistema radicular. Já o cultivar GF 677 apresentou maior número de galhas no sistema radicular, chegando a 126 galhas/g de raiz.The work was carried out with the objective of comparing the response of five different stone fruit rootstocks to two nematode species (Meloidogyne javanica and Meloidogyne incognita. The cultivar GF677, which was obtained from in vitro cultivation and the others rootstocks, were obtained from seedlings. Two month old plants were transplanted and inoculated with a mixture of both nematode species at 30, 60, 70 days after planting, by incorporating 0.2kg of highly infested soil around each cultivar. The development of the roststocks were evaluated at the end of the experiment. Number of galls, ranging from 0 to 5 was used to score the

  6. Physiological and DNA fingerprinting of the bacterial community of Meloidogyne fallax egg masses

    NARCIS (Netherlands)

    Papert, A; Kok, CJ; van Elsas, JD

    2004-01-01

    Bacterial communities associated with the plant-parasitic nematode Meloidogyne fallax egg masses were compared with those present in the rhizoplane. Two agricultural soils with different nematode population dynamics were used in a glasshouse study, with either potato or tomato as host plant for the

  7. Reação de porta-enxertos comerciais de tomateiro a Meloidogyne mayaguensis Reaction of commercial tomato rootstocks plant to Meloidogyne mayaguensis

    Directory of Open Access Journals (Sweden)

    Rafael Ricardo Cantu

    2009-09-01

    Full Text Available O objetivo do presente trabalho foi verificar a resistência ao nematóide Meloidogyne mayaguensis em oito porta-enxertos de tomateiro considerados resistentes à Meloidogyne incognita, M. javanica e M. arenaria, comercializados no Brasil. Os porta-enxertos testados foram: 'Guardião', 'Helper-M', 'Anchor-T', 'Dr. K', 'Kagemuscha', 'TMA 809', 'Magnet' e 'He-Man'. O experimento constou de 9 tratamentos (8 porta-enxertos e a cultivar Rutgers utilizada como padrão de suscetibilidade, com 6 repetições, sendo cada parcela constituída por 1 planta por vaso, mantidas em casa de vegetação. As plantas foram inoculadas com 5.000 ovos e eventuais juvenis infectantes de M. mayaguensis. O experimento seguiu o delineamento inteiramente casualizado. Aos 60 dias da inoculação procederam-se as avaliações, quando foram avaliados os índices de galhas e massas de ovos, número de nematóides no solo e na raiz, peso do sistema radicular e o fator de reprodução. Todos os porta-enxertos estudados demonstraram-se suscetíveis a M. mayaguensis.The objective of this research was to verify the resistance response of eight Brazilian commercial tomato rootstocks to the nematode Meloidogyne mayaguensis. The studied rootstocks were: 'Guardião', 'Helper-M', 'Anchor-T', 'Dr. K', 'Kagemuscha', 'TMA 809', 'Magnet' and 'He-Man'. The experiment consisted of 9 treatments (8 rootstocks and 'Rutgers' used as susceptible control, with 6 replication. Each plot was constituted by 1 plant per pot, maintained in green-house. The plants were inoculated with 5,000 eggs and second stage juvenile of M. mayaguensis. The experimental design was completely randomized. The evaluation was 60 days after inoculation, when the root weight, gall and egg mass index, nematode number in soil and in root and reproduction factor were evaluated. All studied rootstocks were susceptible to M. mayaguensis.

  8. Efecto del follaje de Tagetes minutasobre la nodulación radicular de Meloidogyne incognitaen Capsicum annuum, en invernadero Effect of the foliage of Tagetes minutaon Meloidogyne incognitaroot-galling on Capsicum annuumin a greenhouse

    Directory of Open Access Journals (Sweden)

    Santos Nélida Murga-Gutiérrez

    2013-06-01

    Full Text Available Se investigó el efecto del follaje del “huacatay” Tagetes minutasobre la nodulación radicular producida por el nematodo Meloidogyne incognitaque parasita el “pimiento páprika” Capsicum annuumcultivado en invernadero, con la finalidad de obtener una alternativa de control de este nematodo. Se utilizaron tres grupos experimentales y un testigo, con 12 macetas cada uno, las cuales contenían suelo y arena estériles (1:1. A este substrato se adicionó el follaje de T. minutaal 20, 35 y 50% (v/v según grupo experimental, y el testigo no recibió esta enmienda. En cada maceta se sembró una plántula de C. annuum, y a la semana postsiembra se inoculó 5000 huevos de M. incognita.A las ocho semanas, se evaluaron los nódulos en sus raíces. Todas las plantas presentaron nódulos; aunque, en aquellas de los grupos experimentales el número de éstos fue menor que en las plantas testigo, con diferencia estadística significativa (p 0,05. Se concluye que el follaje de T. minutaadicionado como enmienda orgánica al 20, 35 y 50% al suelo de cultivo de plantas de C. annuum limita la nodulación radicular ocasionada por M. incognita. Lo cual sugiere su uso potencial en el control de este nematodo.The effect of the foliage of Tagetes minuta"huacatay" on Meloidogyne incognitaroot-galling on Capsicum annuum"paprika pepper" cultured in a greenhouse was researched, to obtain a control strategy for this nema-tode. Three experimental groups and one control with 12 pots each were used, which contained sterilized soil and sand (1:1. To this substrate was added cut foliage of T. minutaat 20, 35 and 50% (v/v according to the experimental group, and the control group remained without this amendment. In each pot a seedling of C. annuum was sown, and one week post-seeding was inoculated with 5000 eggs of M. incognita. Eight weeks later the root galling was evaluated. All the plants had root galling; although the number of galls in plants of the experimental

  9. Dicty_cDB: CHL626 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available AW871214 |AW871214.1 ra56d01.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne incognita cDNA 5' similar to ... AW829376 |AW829376.1 ra39d01.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne incognita cDNA 5' similar to

  10. Dicty_cDB: AFK792 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available c11.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5' similar...814 |AW827814.1 ra59b10.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne incognita cDNA 5' similar to WP:K10

  11. Behaviour of Heterodera glycines and Meloidogyne incognita infective juveniles exposed to nematode FMRFamide-like peptides in vitro

    Science.gov (United States)

    Plant-parasitic nematodes depend upon a family of neuropeptides, the FMRFamide-like peptides (FLPs), to regulate locomotion and behavior. To exploit FLPs as leads to novel nematode control agents, an understanding of how specific FLPs affect behavior, and what differences exist between species, is i...

  12. Identification of Meloidogyne incognita, M. javanica and M. arenaria using sequence characterised amplified region (SCAR) based PCR assays

    NARCIS (Netherlands)

    Zijlstra, C.; Donkers-Venne, T.H.M.; Fargette, M.

    2000-01-01

    Three randomly amplified polymorphic DNA (RAPD) markers, OPA-l2420,OPB-061200 and OPA-OI700. species specific to the root-knot nematode species Meloidogyrie arenaria, M. incogriita and M,ja vanica respectively, were identified. After sequencing these RAPD-PCR products, longer primers of 1s to 23 nuc

  13. Ovicidal activity of lactic acid produced by Lysobacter capsici YS1215 on eggs of root-knot nematode, Meloidogyne incognita.

    Science.gov (United States)

    Lee, Yong Seong; Naning, Kyaw Wai; Nguyen, Xuan Hoa; Kim, Sun Bae; Moon, Jae Hak; Kim, Kil Yong

    2014-11-28

    Lysobacter capsici YS1215 isolated from soil previously showed nematicidal potential for biological control of the root-knot nematode. In this study, lactic acid, a nematicidal compound, was isolated from culture filtrate of YS1215, and its ovicidal activity was investigated. Purification and identification of lactic acid were performed by a series of column chromatographies and identified by (1)H and (13)C NMR spectra and GC-MS analysis. Our results showed that bacterial culture filtrate containing lactic acid significantly inhibited egg hatching. The lowest egg hatch rate (5.9%) was found at a high concentration (25 μl/ml) of lactic acid at 5 days after incubation, followed by 20 (15.2%), 15 (23.7%), 10 (29.8%), and 5 (36.4%) μl/ml, while egg hatching in the control (sterile distilled water) was 44.5%. This is the first report of lactic acid as an ovicidal compound, and it may be considered as an alternative of chemical pesticide against root-knot nematodes.

  14. Ação de extratos de plantas medicinais sobre juvenis de Meloidogyne incognita raça 2

    Directory of Open Access Journals (Sweden)

    Maria da Conceição Beserra Martins

    Full Text Available RESUMO Os fitonematoides são parasitas que afetam seriamente as culturas em todo o mundo comprometendo a produção agrícola e, por vezes, inviabilizando a utilização de numerosas áreas de cultivo. A busca por medidas alternativas de controle em substituição aos nematicidas convencionais é uma preocupação mundial, justificando pesquisas com substâncias naturais por serem eficientes e ecologicamente corretos. Objetivou-se neste trabalho avaliar o efeito de extratos vegetais de agrião-do-brejo (Eclipta alba L., alfavaca (Ocimum basilicum, artemísia (Artemísia vulgaris, capim citronela (Cymbopogon winteranus, chambá (Justicia pectoralis, confrei (Symphytum officinalle, hortelã (Mentha x vilosa, lombrigueira (Spigelia anthelmia, mastruz (Chenopodium ambrosioides e menta (Mentha arvensis na motilidade e mortalidade de juvenis de Meloidogyneincognita raça 2. Os extratos, obtidos a partir de folhas secas sob infusão ou sob maceração em água, foram diluídos e distribuídos em placas de Petri às quais foram adicionados 50 juvenis de segundo estádio (J2. Após permanecerem por 48 horas nos extratos, todos os J2 móveis ou imóveis foram contados e, em seguida, transferidos para água determinando-se, após 24 horas, a porcentagem de J2 mortos. Os J2 ainda ativos foram inoculados em mudas de tomateiro ‘Santa Clara’ em casa de vegetação para avaliar a sua infectividade. Os extratos macerados das plantas medicinais, excetuando-se capim citronela, hortelã e menta, apresentaram alta atividade nematicida com mais de 70% de J2 mortos. Mortalidade total ocorreu em extratos de lombrigueira, agrião-do-brejo e mastruz. A ausência de galhas nas raízes de tomateiros inoculados confirmou o efeito tóxico desses extratos.

  15. Precision mapping and identification of candidate genes for a QTL affecting Meloidogyne incognita reproduction in Upland cotton

    Science.gov (United States)

    The resistant line Auburn 623RNR and a number of elite breeding lines derived from it remain the most important source of root-knot nematode (RKN) resistance because they exhibit the highest level of resistance to RKN known to date in Upland cotton (Gossypium hirsutum L). Prior genetic mapping analy...

  16. The use of root gall ratings to determine high risk zones in cotton fields infested by Meloidogyne Incognita

    Science.gov (United States)

    Cotton farmers need a reliable, accurate, and inexpensive method for determining the potential threat of root-knot nematodes (RKN) to cotton within individual fields for site specific application of nematicides. Evaluation of cotton roots for RKN galling at harvest may be an alternative to soil ana...

  17. Assessment of DAPG-producing Pseudomonas fluorescens for management of Meloidogyne incognita and Fusarium oxysporum on watermelon

    Science.gov (United States)

    Pseudomonas fluorescens isolates Clinto 1R, Wayne 1R and Wood 1R, which produce the antibiotic 2,4-diacetylphloroglucinol (DAPG), can suppress soilborne diseases and promote plant growth. Consequently, these beneficial bacterial isolates were tested on watermelon plants for suppression of Meloidogy...

  18. Effets de l'iboga (Tabernanthe iboga Baillon sur les nématodes à galles (Meloidogyne sp. parasites de tomate

    Directory of Open Access Journals (Sweden)

    Bayonne, L.

    2005-01-01

    Full Text Available Effects of Iboga (Tabernanthe iboga Baillon on the Root-Knot Nematodes (Meloidogyne sp. in Tomato. The tomato crop in tropical areas arises phytosanitary problems because of many disastrous parasites among which the Meloidogyne genus are in the origin of important damages and the origin of the tomato production decrease in Gabon. How can people manage to control these parasites by using local plants? Out of the chemical control, the works we have done, focused on the usage of Tabernanthe iboga as a biological control agent of crop protection. The results of these experiences show that the iboga decoction seems to be able to reduce considerably the Meloidogyne population, and to protect the crop.

  19. Biological Control of Meloidogyne hapla Using an Antagonistic Bacterium

    Directory of Open Access Journals (Sweden)

    Jiyeong Park

    2014-09-01

    Full Text Available We examined the efficacy of a bacterium for biocontrol of the root-knot nematode (RKN Meloidogyne hapla in carrot (Daucus carota subsp. sativus and tomato (Solanum lycopersicum. Among 542 bacterial isolates from various soils and plants, the highest nematode mortality was observed for treatments with isolate C1-7, which was identified as Bacillus cereus based on cultural and morphological characteristics, the Biolog program, and 16S rRNA sequencing analyses. The population density and the nematicidal activity of B. cereus C1-7 remained high until the end of culture in brain heart infusion broth, suggesting that it may have sustainable biocontrol potential. In pot experiments, the biocontrol efficacy of B. cereus C1-7 was high, showing complete inhibition of root gall or egg mass formation by RKN in carrot and tomato plants, and subsequently reducing RKN damage and suppressing nematode population growth, respectively. Light microscopy of RKN-infected carrot root tissues treated with C1-7 showed reduced formation of gall cells and fully developed giant cells, while extensive gall cells and fully mature giant cells with prominent cell wall ingrowths formed in the untreated control plants infected with RKNs. These histopathological characteristics may be the result of residual or systemic biocontrol activity of the bacterium, which may coincide with the biocontrol efficacies of nematodes in pots. These results suggest that B. cereus C1-7 can be used as a biocontrol agent for M. hapla.

  20. Effects of Bahiagrass and Nematicides on Meloidogyne arenaria on Peanut.

    Science.gov (United States)

    Dickson, D W; Hewlett, T E

    1989-10-01

    A field infested with Meloidogyne arenaria and with a history of peanut yield losses was divided into two equal parts. One-half of the field (bahia site) was planted to bahiagrass in 1986 and maintained through 1987. The other half (peanut site) was planted to soybean in 1986 and peanut in 1987 with hairy vetch planted each fall as a cover crop. In 1988 identical nematicide treatments including 1,3-dichloropropene (1,3-D), aldicarb, and ethoprop were applied to the two sites, and the sites were planted with the peanut cultivar Florunner. At mid-season, population levels of M. arenaria second-stage juveniles in the bahia site were relatively low, compared with those in the peanut site. At harvest, however, population levels were high in both sites. No nematicide treatment increased yields over the untreated control in either site (P

  1. The map-1 gene family in root-knot nematodes, Meloidogyne spp.: a set of taxonomically restricted genes specific to clonal species.

    Directory of Open Access Journals (Sweden)

    Iva Tomalova

    Full Text Available Taxonomically restricted genes (TRGs, i.e., genes that are restricted to a limited subset of phylogenetically related organisms, may be important in adaptation. In parasitic organisms, TRG-encoded proteins are possible determinants of the specificity of host-parasite interactions. In the root-knot nematode (RKN Meloidogyne incognita, the map-1 gene family encodes expansin-like proteins that are secreted into plant tissues during parasitism, thought to act as effectors to promote successful root infection. MAP-1 proteins exhibit a modular architecture, with variable number and arrangement of 58 and 13-aa domains in their central part. Here, we address the evolutionary origins of this gene family using a combination of bioinformatics and molecular biology approaches. Map-1 genes were solely identified in one single member of the phylum Nematoda, i.e., the genus Meloidogyne, and not detected in any other nematode, thus indicating that the map-1 gene family is indeed a TRG family. A phylogenetic analysis of the distribution of map-1 genes in RKNs further showed that these genes are specifically present in species that reproduce by mitotic parthenogenesis, with the exception of M. floridensis, and could not be detected in RKNs reproducing by either meiotic parthenogenesis or amphimixis. These results highlight the divergence between mitotic and meiotic RKN species as a critical transition in the evolutionary history of these parasites. Analysis of the sequence conservation and organization of repeated domains in map-1 genes suggests that gene duplication(s together with domain loss/duplication have contributed to the evolution of the map-1 family, and that some strong selection mechanism may be acting upon these genes to maintain their functional role(s in the specificity of the plant-RKN interactions.

  2. Reproduction of Meloidogyne javanica on Plant Roots Genetically Transformed by Agrobacterium rhizogenes.

    Science.gov (United States)

    Verdejo, S; Jaffee, B A; Mankau, R

    1988-10-01

    Reproduction of Meloidogyne javanica was compared on several Agrobacterium rhizogenes-transformed root cultures under monoxenic conditions. M. javanica reproduced on all transformed roots tested; however, more females and eggs were obtained on potato and South Australian Early Dwarf Red tomato than on bindweed, Tropic tomato, lima bean, or carrot. Roots that grew at moderate rates into the agar and produced many secondary roots supported the highest reproduction. Numbers of females produced in cultures of transformed potato roots increased with increasing nematode inoculum levels, whether inoculum was dispersed eggs or juveniles. Females appeared smaller, produced fewer eggs, and were found in coalesced galls at the higher inoculum levels. The ratio between the final and initial population decreased sharply as the juvenile inoculum increased. The second-stage juvenile was preferred to dispersed eggs or egg masses for inoculation of tissue culture systems because quantity and viability of inoculum were easily assessed. Meloidogyne javanica reared on transformed root cultures were able to complete their life cycles on new transformed root cultures or greenhouse tomato plants.

  3. Dicty_cDB: VFH250 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 482.1 rb02b12.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5' similar to SW:YR44_CAEEL... mRNA sequence. 46 0.39 1 BM774872 |BM774872.1 ra98f07.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne i...773792.1 ra86a02.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cD... ;, mRNA sequence. 46 0.39 1 BM773831 |BM773831.1 ra86d08.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyn...ogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5' similar to SW:YR44_CAEEL Q09390 HYPOTHETICAL 23

  4. A real-time PCR assay to identify Meloidogyne minor

    NARCIS (Netherlands)

    Weerdt, de M.; Kox, L.; Wayenberge, L.; Viaene, N.; Zijlstra, C.

    2011-01-01

    Meloidogyne minor is a small root-knot nematode that causes yellow patch disease in golf courses and severe quality damage in potatoes. It was described in 2004 and has been detected in The Netherlands, England, Wales, Northern Ireland, Ireland and Belgium. The nematode often appears together with M

  5. Distribution, hosts and identification of Meloidogyne partityla in the USA

    Science.gov (United States)

    Pecan, Carya illinoensis, is an economically important nut crop and member of the Juglandaceae native to the southern USA. Discovered in South Africa in 1986, Meloidogyne partityla was first found infecting pecan in USA in 1996 and currently occurs in Texas, New Mexico, Georgia, Arizona, Oklahoma a...

  6. IDENTIFICACIÓN DE GENES CANDIDATOS DE PATOGENICIDAD EN LA INTERACCIÓN DE LA CEPA CENICAFE 9501 CON EL NEMÁTODO DEL NUDO RADICAL Meloidogyne spp. IDENTIFICATION OF PATHOGENIC CANDIDATES GENES IN THE INTERACTION OF THE CENICAFE 9501 STRAIN WITH THE ROOT KNOT NEMATODE Meloidogyne spp.

    Directory of Open Access Journals (Sweden)

    Nadya Lorena Cardona Bustos

    2008-12-01

    Full Text Available En 1997 se registró por primera vez el aislamiento de un hongo Hyphomycete de suelos de Chinchiná (Caldas, Colombia atacando huevos y otros estadios biológicos de las especies de nematodos fitoparásitos Meloidogyne incognita y M. javanica provenientes de lotes comerciales con café. Debido a la imposibilidad de clasificarlo taxonómicamente en los géneros actuales, este aislamiento se ha denominado temporalmente como CENICAFE 9501. Dado su potencial como biocontrolador, se propuso identificar genes candidatos involucrados en el proceso de patogenicidad de huevos de Meloidogyne. Con este fin se construyeron librerías diferenciales mediante el método de hibridación sustractiva. La secuenciación de 188 clones obtenidos permitió identificar 80 unigenes, de los cuales el mayor porcentaje correspondió a secuencias sin homología (32%, seguidas por genes candidatos a funciones de patogénesis (22%, transporte celular (17%, síntesis de proteínas (11% y en menor proporción aquellos involucrados con transcripción y metabolismo primario (18%. Dentro de aquellos genes que contienen marcos de lectura con homología a proteínas que intervienen en la patogenicidad se encuentran una peptidasa, un receptor para sitios de ubiquitinación, una deubiquinasa, una ubiquinona oxidoreductasa, proteína relacionada con la degradación de pared celular, glicosil hidrolasa e hidroxilasa de ácidos grasos, asi como una serin proteasa. Se hace necesaria la validación de las funciones putativas de estos genes candidatos con el fin de incrementar el conocimiento básico de la fisiología de este hongo con potencial biorregulador.In 1997 it was reported for the first time from soil isolation of a Hyphomycete fungus from Chinchiná ( Caldas, Colombia , attacking eggs and other biological stages of the plant parasite nematodes Meloidogyne incognita and M. javanica, from commercial coffee plots. Due to the impossibility to classify it taxonomically under current

  7. Variabilidade espacial de Meloidogyne javanica em soja

    Directory of Open Access Journals (Sweden)

    Andressa Lima de Brida

    2016-06-01

    Full Text Available RESUMO A soja é considerada uma das mais importantes culturas do agronegócio no Brasil. Os levantamentos populacionais de fitoparasitos, é uma ferramenta importante na presença de nematoides e na detecçao dos prejuizos. O presente estudo teve como objetivo, utilizando como ferramenta, a geoestatística, verificar a variabilidade espacial de Meloidogyne javanica em duas lavouras de soja, uma apresentando plantas com sintomas característicos do parasitismo do nematoide e outra área com plantas sem sintomas. O estudo foi realizado no município de Araruna, estado do Paraná, ambas cultivadas com soja cultivar BMX Potência RR. Coletaram-se solo e raiz seguindo malha irregular de 50 pontos georreferenciados. Para verificar a existência e estimar o grau de dependência espacial entre as populações, utilizou-se a análise geoestatística. Após o ajuste do variograma foi realizado a krigagem e sequencialmente o mapa de distribuição espacial de nematoides nas áreas. Todo processo geoestatístico foi realizado com o programa computacional GS+. Somente em quatro pontos foram detectados nematoides nas amostras de solo, e em baixo nível populacional, por isso, tais dados não foram analisados com a geoestatística. Na área apresentando plantas amareladas e com tamanho reduzido, em 60% das amostras foi detectado a presença de M. javanica, sendo que a população obtida variou de 0 a 70.992 nematoides em 10g de raiz, com média de 3.807. O variograma ajustou-se ao modelo esférico, com alcance de 30,80 m e dependência espacial de 86%, nesse caso seria necessária a coleta de nove subamostras para representar um hectare de forma satisfatória. Na área onde não foram observadas plantas com sintomas visíveis, 38% das amostras estavam com M. javanica, e com baixo nível populacional. A população obtida variou de 0 a 2.184 nematoides em 10g de raiz, com media de 262. O alcance obtido foi de 11,60 m, com dependência espacial de 99% e ajuste

  8. RNA interference of effector gene 16D10 leads to broad meloidogyne resistance in potato

    Science.gov (United States)

    Root-knot nematodes (Meloidogyne spp.) are a significant problem in potato (Solanum tuberosum) production. There is no known Meloidogyne resistance gene in cultivated potato, even though sources of resistance were identified in wild potato species. The objective of this study was to generate stable ...

  9. Effect of Carbamate, Organophosphate, and Avermectin Nematicides on Oxygen Consumption by Three Meloidogyne spp.

    Science.gov (United States)

    Nordmeyer, D; Dickson, D W

    1989-10-01

    Second-stage juveniles (I2) of Meloidogyne arenaria consumed more oxygen (P nematicide used. Except for aldicarb, there was no differential sensitivity among the three nematode species. Meloidogyne javanica had a greater percentage decrease (P nematicides were positively correlated (P

  10. Dicty_cDB: SSC788 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ENCE, 1 ordered piece. 40 0.49 5 BM882146 |BM882146.1 rb26d03.y1 Meloidogyne incognita egg pAMP1 Bird Meloid... BM774808 |BM774808.1 ra97h06.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5', mRNA se

  11. Heterodera glycines cysts contain an extensive array of endoproteases as well as inhibitors of proteases in H. glycines and Meloidogyne incognita infective juvenile stages

    Science.gov (United States)

    Heterodera glycines cysts contain proteases, and inhibitors of protease activities in various nematode species. In this investigation, proteases in H. glycines cysts were identified using a commercially available FRET-peptide library comprising 512 peptide pools qualified to detect up to 4 endoprot...

  12. Tomato rootstocks for the control of Meloidogyne spp.

    OpenAIRE

    2010-01-01

    Se determinó la respuesta de resistencia de 10 patrones de tomate a una población avirulenta de Meloidogyne javanica en maceta. Los ensayos se realizaron en primavera, cuando las temperaturas permitían la expresión fenotípica de la resistencia del gen Mi-1 (28˚C), en verano sometidos a altas temperaturas y en campo, exponiéndolos a altas densidades poblacionales del nematodo. A temperaturas inferiores a 28˚C los patrones mostraron gran variabilidad en la respuesta de resistencia que...

  13. Temporal efficacy of selected nematicides on meloidogyne species on tobacco.

    Science.gov (United States)

    Melton, T A; Barker, K R; Koenning, S R; Powell, N T

    1995-09-01

    Aldicarb, ethoprop, and fenamiphos were evaluated for their efficacy in controlling various species of root-knot nematodes on flue-cured tobacco and for their residual activity, as determined through periodic sampling and bioassays of soil taken from field plots. Field experiments were conducted at five locations over 2 years with flue-cured tobacco. Soil in plots treated with nematicides were formed into high, wide beds before transplanting with 'Coker 371-Gold' or 'K 326' tobacco. Residual control of Meloidogyne spp. was greatest (P nematicidal efficacy of all compounds varied with site and season, fenamiphos and aldicarb generally produced the highest yields.

  14. Dicty_cDB: CHG178 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 18 2 AW828903 |AW828903.1 ra69e06.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyn...NA sequence. 76 2e-11 2 AW871512 |AW871512.1 ra78g07.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne incogn

  15. On the species status of the root-knot nematode Meloidogyne ulmi Palmisano & Ambrogioni, 2000 (Nematoda, Meloidogynidae

    Directory of Open Access Journals (Sweden)

    Mohammed Ahmed

    2013-12-01

    Full Text Available The root-knot nematode Meloidogyne ulmi is synonymised with Meloidogyne mali based on morphological and morphometric similarities, common hosts, as well as biochemical similarities at both protein and DNA levels. M. mali was first described in Japan on Malus prunifolia Borkh.; and M. ulmi in Italy on Ulmus chenmoui W.C. Cheng. Morphological and morphometric studies of their holo- and paratypes revealed important similarities in the major characters as well as some general variability in a few others. Host test also showed that besides the two species being able to parasitize the type hosts of the other, they share some other common hosts. Our study of the esterase and malate dehydrogenase isozyme phenotypes of some M. ulmi populations gave a perfectly comparable result to that already known for M. mali. Finally, phylogenetic studies of their SSU and LSU rDNA sequence data revealed that the two are not distinguishable at DNA level. All these put together, leave strong evidences to support the fact that M. ulmi is not a valid species, but a junior synonym of M. mali. Brief discussion on the biology and life cycle of M. mali is given. An overview of all known hosts and the possible distribution of M. mali in Europe are also presented.

  16. On the species status of the root-knot nematode Meloidogyne mayaguensis Rammah & Hirschmann, 1988

    NARCIS (Netherlands)

    Karssen, G.; Liao, J.; Kan, Z.; Heese, van E.; Nijs, L.J.M.F.

    2012-01-01

    Holo- and paratypes of the root-knot nematodes Meloidogyne mayaguensis Rammah & Hirschmann, 1988 and M. enterolobii Yang & Eisenback, 1983 were morphometrically and morphologically compared. All observed female, male and second-stage juvenile morphometrical and morphological characters are i

  17. Evaluation of Steam and Soil Solarization for Meloidogyne arenaria Control in Florida Floriculture Crops.

    Science.gov (United States)

    Kokalis-Burelle, Nancy; Rosskopf, Erin N; Butler, David M; Fennimore, Steven A; Holzinger, John

    2016-09-01

    Steam and soil solarization were investigated for control of the root-knot nematode Meloidogyne arenaria in 2 yr of field trials on a commercial flower farm in Florida. The objective was to determine if preplant steam treatments in combination with solarization, or solarization alone effectively controlled nematodes compared to methyl bromide (MeBr). Trials were conducted in a field with naturally occurring populations of M. arenaria. Treatments were solarization alone, steam treatment after solarization using standard 7.6-cm-diameter perforated plastic drain tile (steam 1), steam treatment following solarization using custom-drilled plastic drain tile with 1.6-mm holes spaced every 3.8 cm (steam 2), and MeBr applied at 392 kg/ha 80:20 MeBr:chloropicrin. Drain tiles were buried approximately 35 cm deep with four tiles per 1.8 by 30 m plot. Steam application followed a 4-wk solarization period concluding in mid-October. All steam was generated using a Sioux propane boiler system. Plots were steamed for sufficient time to reach the target temperature of 70°C for 20 min. Solarization plastic was retained on the plots during steaming and plots were covered with a single layer of carpet padding to provide additional insulation. The floriculture crops larkspur (Delphinium elatum and Delphinium × belladonna), snapdragon (Antirrhinum majus), and sunflower (Helianthus annuus) were produced according to standard commercial practices. One month after treatment in both years of the study, soil populations of M. arenaria were lower in both steam treatments and in MeBr compared to solarization alone. At the end of the season in both years, galling on larkspur, snapdragon, and sunflowers was lower in both steam treatments than in solarization. Both steam treatments also provided control of M. arenaria in soil at the end of the season comparable to, or exceeding that provided by MeBr. Both steam treatments also reduced M. arenaria in snapdragon roots comparable to, or exceeding

  18. Evaluation of Steam and Soil Solarization for Meloidogyne arenaria Control in Florida Floriculture Crops

    Science.gov (United States)

    Kokalis-Burelle, Nancy; Rosskopf, Erin N.; Butler, David M.; Fennimore, Steven A.; Holzinger, John

    2016-01-01

    Steam and soil solarization were investigated for control of the root-knot nematode Meloidogyne arenaria in 2 yr of field trials on a commercial flower farm in Florida. The objective was to determine if preplant steam treatments in combination with solarization, or solarization alone effectively controlled nematodes compared to methyl bromide (MeBr). Trials were conducted in a field with naturally occurring populations of M. arenaria. Treatments were solarization alone, steam treatment after solarization using standard 7.6-cm-diameter perforated plastic drain tile (steam 1), steam treatment following solarization using custom-drilled plastic drain tile with 1.6-mm holes spaced every 3.8 cm (steam 2), and MeBr applied at 392 kg/ha 80:20 MeBr:chloropicrin. Drain tiles were buried approximately 35 cm deep with four tiles per 1.8 by 30 m plot. Steam application followed a 4-wk solarization period concluding in mid-October. All steam was generated using a Sioux propane boiler system. Plots were steamed for sufficient time to reach the target temperature of 70°C for 20 min. Solarization plastic was retained on the plots during steaming and plots were covered with a single layer of carpet padding to provide additional insulation. The floriculture crops larkspur (Delphinium elatum and Delphinium × belladonna), snapdragon (Antirrhinum majus), and sunflower (Helianthus annuus) were produced according to standard commercial practices. One month after treatment in both years of the study, soil populations of M. arenaria were lower in both steam treatments and in MeBr compared to solarization alone. At the end of the season in both years, galling on larkspur, snapdragon, and sunflowers was lower in both steam treatments than in solarization. Both steam treatments also provided control of M. arenaria in soil at the end of the season comparable to, or exceeding that provided by MeBr. Both steam treatments also reduced M. arenaria in snapdragon roots comparable to, or exceeding

  19. Trigonella foenum-graecum (fenugreek-mediated suppression of Meloidogyne javanica in mungbean

    Directory of Open Access Journals (Sweden)

    Tayyaba Zia

    2013-12-01

    Full Text Available Soil amendments with powdered seeds of Trigonella foenum - graecum (fenugreek caused soil suppressiveness against Meloidogyne javanica. Decomposed seeds of fenugreek caused marked reduction in nematode population densities and subsequent root-knot development as compared to the aqueous extract of the seeds indicating that some indirect factors are involved in the suppression of root-knot nematode. Both decomposed seeds and aqueous extracts enhanced plant height and fresh weights of shoot whereas root growth remained uninfluenced. Changes in fungal communities associated with nematode control were studied by comparing population numbers of fungi in the soil and in internal root tissues (endorhiza in non-amended and fenugreekamended soils. Acremonium sp., Chaetomium globosum, Fusarium solani, Macrophomina phaseolina and Rhizoctonia solani were found to colonize inner root tissues of mungbean. Acremonium sp., C. globosum and F.solani were isolated in a relatively higher frequency from roots growing in the amended soils while M. phaseolina and R. solani colonized greatly in roots growing in non-amended soil. Of the fungi isolated from soils, Penicillium brefaldianum caused maximum juvenile mortality of M.javanica whereas F.solani caused greatest inhibition of egg hatch.

  20. Control of Heterodera carotae, Ditylenchus dipsaci, and Meloidogyne javanica with Fumigant and Nonfumigant Nematicides.

    Science.gov (United States)

    Greco, N; Elia, F; Brandonisio, A

    1986-07-01

    Five field trials were conducted in Italy in 1983 and 1984 to test the efficacy of isazofos and benfuracarb in controlling Heterodera carotae on carrot, Ditylenchus dipsaci on onion, and Meloidogyne javanica on tomato. Methyl isothiocyanate (MIT) was tested against H. carotae and M. javanica. Single (10 kg a.i./ha) and split (5 + 5 kg a.i./ha) applications of isazofos gave yield increases of carrot and onion similar to those obtained with DD (300 liters/ha) and aldicarb (10 kg a.i./ha). Population densities of H. carotae in carrot roots at harvest and of M. javanica in tomato roots 2 months after transplanting were also suppressed by isazofos. Benfuracarb (10 kg a.i./ha increased onion yields in a field infested with D. dipsaci, but it was not effective against H. carotae or M. javanica. The efficacy of MIT at 400 and 600 liters/ha was similar to that of MIT + DD (Di-Trapex) at 300 liters/ha. Both nematicides inhibited hatch of H. carotae eggs and decreased the soil population density of M. javanica.

  1. Resistance and host-response of selected plants to Meloidogyne megadora.

    Science.gov (United States)

    de Almeida, A M S F; de A Santos, M S N

    2002-06-01

    Fourteen plant species, including 30 genotypes, were assessed for host suitability to Meloidogyne megadora in a growth room at 20 to 28 degrees C. Host suitability was based on the gall index (GI) and the reproduction factor (Rf):final population density (Pf)/initial population density (Pi). The presence of distinct galling was observed on roots of six plant species, and reproduction occurred on five of the 14 species tested. Three cultivars of cantaloupe (cvs. Branco do Ribatejo, Concerto, and Galia), three of cucumber (cvs. LM 809, Half Long Palmetto, and Market More), six of banana (cvs. Maçá, Ouro Branco, Ouro Roxo, Prata, Páo, and Valery), and one of broad bean (cv. Algarve) were considered susceptible (Pf/Pi > 1). Resistant cultivars (Pf/Pi = 0) included beet (cv, Crosby), pepper (cv. LM 204), watermelon (cvs. Black Magic and Crimson Sweet), tomato (cvs. Moneymaker and Rossol), radish (cv. Cherry Belle), and corn (cv. Dunia); sunn hemp and black velvetbean genotypes were also resistant. All Brassica cultivars were galled, although no egg masses were observed (Pf/Pi = 0), and classified as resistant/hypersensitive.

  2. Dicty_cDB: VFD705 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ing significant alignments: (bits) Value N BM774794 |BM774794.1 ra97g03.y1 Meloidogyne incognita egg pAMP1 Bird... CHROMOSOME X. [1] ;, mRNA sequence. 72 2e-20 3 BM773715 |BM773715.1 ra85b05.y1 Meloidogyne incognita egg pAMP1 Bird...N. [1] ;, mRNA sequence. 72 4e-18 3 BM881619 |BM881619.1 rb12a07.y1 Meloidogyne incognita egg pAMP1 Bird Mel... |BM881752.1 rb13f01.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5' similar to TR:Q9X... rb26c12.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5' similar to TR:O75710 O75710 M

  3. Dicty_cDB: VFD505 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ficant alignments: (bits) Value N BM774794 |BM774794.1 ra97g03.y1 Meloidogyne incognita egg pAMP1 Bird...PROTEIN F49E2.1 IN CHROMOSOME X. [1] ;, mRNA sequence. 72 2e-20 3 BM773715 |BM773715.1 ra85b05.y1 Meloidogyne incognita egg pAMP1 Bir... mRNA sequence. 72 3e-18 3 BM881619 |BM881619.1 rb12a07.y1 Meloidogyne incognita egg pAMP1 Bird...2 4e-18 2 BM881752 |BM881752.1 rb13f01.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5'...y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5' similar to

  4. Biology of Meloidogyne platani Hirschmann Parasitic on Sycamore, Platanus occidentalis.

    Science.gov (United States)

    Al-Hazmi, A S; Sasser, J N

    1982-04-01

    The development of Meloidogyne platani on sycamore was followed for 40 days (22-28 C). Juveniles penetrated the feeder roots behind the root cap and invaded the vascular cylinder within 3 days after inoculation. All subsequent development of the nematodes and host effects occurred only within the stele. The second juvenile molt and sex differentiation occurred by the 17th day. Young females were observed by the 26th day. Eggs were observed inside the roots by the 35th day and were exposed to the surface of galls by the 40th day. In pathogenicity studies, a significant negative correlation was shown to exist between fresh shoot and root weights and inoculum density. Besides sycamore, white ash was the only hardwood species tested to become infected. Of the herbacious plants tested, tobacco was heavily galled, tomato and watermelon moderately galled, and pepper only slightly galled. Egg production was moderate on tobacco, slight on tomato and watermelon, and absent on pepper.

  5. Dicty_cDB: AFO449 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available gnments: (bits) Value N BM774584 |BM774584.1 ra95c11.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne inc...ssed in fertilized egg. 42 3e-05 3 AW827814 |AW827814.1 ra59b10.y1 Bird-Rao Meloi...sequence. 40 8e-05 3 AW871572 |AW871572.1 ra79e06.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne incognita

  6. Effects of silicon on the penetration and reproduction events of Meloidogyne exigua on coffee roots

    Directory of Open Access Journals (Sweden)

    Rodrigo Vieira Silva

    2015-06-01

    Full Text Available Considering that the root-knot nematode Meloidogyne exigua has caused great yield losses to coffee production in Brazil, this study aimed to determine whether the penetration and the reproduction events of this nematode on the roots of plants from two coffee cultivars with different levels of basal resistance to this nematode could be affected by silicon (Si. Coffee plants from the cultivars Catuaí and IAPAR 59, which are susceptible and resistant, respectively, to M. exigua, were grown in pots containing Si-deficient soil that was amended with either calcium silicate (+Si or calcium carbonate (–Si. The Si concentration on the root tissue significantly increased by 159 and 97% for the +Si plants from the cultivars Catuaí and IAPAR 59, respectively, compared to the –Si plants of these cultivars. The population of M. exigua, the number of galls and the number of eggs were significantly reduced on the roots of the +Si plants of the cultivars Catuaí and IAPAR 59 compared to the –Si plants of these cultivars. It was concluded that the development and reproduction events of M. exigua were negatively impacted on the roots of coffee plants supplied with Si.

  7. Field level risk assessment for root-knot nematodes in lima beans

    Science.gov (United States)

    Southern Root-Knot Nematode (RKN), Meloidogyne incognita, is a major yield limiting pest in lima beans (Phaseolus lunatus). RKN are not evenly distributed through fields and population dynamics are fluid making whole field management challenging. The objectives of this research were to characterize ...

  8. Nematicide Effect of Various Organic Soil Amendments on Meloidogyne ethiopica Whitehead, 1968, on Potted Vine Plants Efecto Nematicida de Varias Enmiendas Orgánicas Sobre Meloidogyne ethiopica Whitehead, 1968, en Plantas de Vid en Macetas

    Directory of Open Access Journals (Sweden)

    Lucia Rivera

    2008-09-01

    Full Text Available Five organic soil amendments were evaluated for their nematicide effect on root-knot Meloidogyne ethiopica Whitehead, 1968, on potted Vitis vinifera L. var. Chardonnay plants. The amendments included two immature composts: Compost A made with tea (Camellia sinensis (L. Kuntze residues, broiler litter and grape pomace; Compost B made with tea residues, rachis and grape pomace; and separately dried tea residues, grape pomace and broiler litter. These amendments were either incorporated or applied as cover to the substrate in 5 L pots at the beginning of spring. A chemical treatment with the nematicide fenamiphos and a control with substrate only were added for comparisons. The assay was composed of 11 treatments with six replicates, with a grape plant as experimental unit. Seven months later, the assessment of the treatments was carried out based on number of second stage juvenile, nodules, eggs per root gram and reproductive index. Fresh aerial and root plant weight were also measured. The chemical treatment presented the lowest final population of M. ethiopica. When evaluating the nematicide action of the organic amendments: compost A soil-incorporated and both grape pomace and solid dry tea residue as covers obtained low reproductive indexes, similar to the chemical treatment and control (P ≤ 0.05. No differences in aerial fresh weight were determined. However, the chemical treatment showed the smallest root mass as compared to compost B and solid dry tea residues, both as cover.Se realizó un experimento en macetas con plantas enraizadas de Vitis vinífera L. var. Chardonnay para evaluar el efecto nematicida de diferentes enmiendas orgánicas sobre el nematodo agallador Meloidogyne ethiopica Whitehead, 1968. Se usaron dos composts inmaduros: Compost A, elaborado con residuos de té (Camellia sinensis (L. Kuntze, guano de pollo seco y orujo de uva; Compost B, elaborado con residuos de té, escobajo y orujo de uva; y separadamente residuos s

  9. Relationship of Resistance to Meloidogyne chitwoodi (race 2) and M. hapla in Alfalfa

    OpenAIRE

    Per H McCord

    2012-01-01

    In the Pacific Northwest, alfalfa (Medicago sativa) is host to two species of root-knot nematodes, including race 2 of the Columbia root-knot nematode (Meloidogyne chitwoodi) and the northern root-knot nematode (Meloidogyne hapla). In addition to the damage caused to alfalfa itself by M. hapla, alfalfa’s host status to both species leaves large numbers of nematodes available to damage rotation crops, of which potato is the most important. A nematode-resistant alfalfa germplasm release, W12SR2...

  10. Dicty_cDB: VSK131 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 1 rb27a07.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5' s...MER31 repetitive element ;, mRNA sequence. 48 0.14 1 AW828823 |AW828823.1 ra74e11.y1 Bird-Rao Meloidogyne in

  11. Dicty_cDB: CHO517 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available lone RP11-560G8 on chromosome 9. 48 0.18 1 AW829533 |AW829533.1 ra41c11.y1 Bird-Rao Meloidogyne incognita J2...1 2 AW830038 |AW830038.1 ra48h04.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne

  12. COMBINING EFFECTS OF CULTURAL PRACTICES AND RESISTANT CULTIVARS ON REDUCING THE INCIDENCE OF Meloidogyne spp. AND Thrips palmy Karny ON POTATO

    Directory of Open Access Journals (Sweden)

    Wiwin Setiawati

    2013-05-01

    Full Text Available Root-knot nematode (Meloidogyne spp. and melon thrips (Thrips palmy Karny are two serious pests on potato. These pests are conventionally controlled with synthetic pesticides. Cultural practices based on integrated pest management (IPM are alternative methods to control these pests. The study aimed to determine the effectiveness of combined applications of cultural practices and potato cultivars in reducing the incidences of nematode and thrips. Treatments evaluated were methods of nematode and thrips control by implementing IPM and conventional practices. A split-plot randomized complete block design with four replications was  sed. The main plots were IPM or cultural practices (subsoiling, soil solarization and use of trap crop of marigold Tagetes erecta and conventional practices using synthetic pesticides. The subplots were five potato cultivars, i.e. No. 095 (Herta x FLS–17, 720050/Kikondo, 676068/ I.1085, Granola, and Atlantic. The results showed that applications of cultural practices in combination with potato cultivars reduced Meloidogyne spp. population and potato tuber damage by 53.70% and 61.36%, respectively, as well as a significantly decreased thrips population. In the cultural control plots, thrips populations were below the action threshold (10.0 nymphs per leaf, therefore no single application of pesticide was used. This was in contrast to the conventional control treatments where insecticide was spayed 10 times until harvest. The subsoiling and solarization cut off the life cycle of the thrips and any survive thrips were trapped by marigold plant. Population of T. palmi on the five potato cultivars differed significantly; the lowest population was found on the cultivars No. 095 (Herta x FLS-17 and 676068/I.1085. The cultural control practices combined with potato cultivar No. 095 (Herta x FLS–17 were the best treatment for controlling Meloidogyne spp. and T. palmi on potato and also produced the highest yield (31.01 t

  13. Host status of own-rooted Vitis vinifera varieties to Meloidogyne hapla

    Science.gov (United States)

    Plant-parasitic nematodes are microscopic soil worms that attack the roots of grape plants and cause yield loss. One of the most commonly encountered plant-parasitic nematodes in eastern Washington Vitis vinifera vineyards is Meloidogyne hapla, the northern root-knot nematode. The selection of plant...

  14. Morphological and physiological variability of species of meloidogyne in West Africa and implications of their control

    NARCIS (Netherlands)

    Netscher, C.

    1978-01-01

    The extreme morphological and physiological variability of certain rootknot nematodes (Meloidogyne spp.) and its implication on the development of control methods of these parasites, based upon crop rotations and the use of resistant varieties of otherwise susceptible crops are discussed.In a review

  15. First report of the root-knot nematode Meloidogyne ethiopica on tomato in Slovenia

    NARCIS (Netherlands)

    Sirca, S.; Urek, G.; Karssen, G.

    2004-01-01

    The root-knot nematode Meloidogyne ethiopica Whitehead originally described from Tanzania is also distributed in South Africa, Zimbabwe, and Ethiopia (3). Although this species is a relatively unknown root-knot nematode, M. ethiopica parasitizes several economical important crops, such as tomato, co

  16. First report of the root-knot nematode Meloidogyne minor on turfgrass in Belgium

    NARCIS (Netherlands)

    Viaene, N.; Wiseborn, D.B.; Karssen, G.

    2007-01-01

    The root-knot nematode, Meloidogyne minor, was described during 2004 after it was found on potato roots in a field in the Netherlands and in golf courses in England, Wales, and Ireland (2). Since it is associated with yellow patch disease in turf grass and causes deformation of potato tubers (2), it

  17. Meloidogyne duytsi n. sp. (Nematoda : Heteroderidae), a root- knot nematode from Dutch coastal foredunes

    NARCIS (Netherlands)

    Karssen, G.; Van Aelst, A.; Van der Putten, W.H.

    1998-01-01

    A root-knot nematode, Meloidogyne duytsi n. sp., is described and illustrated from Elymus farctus (Viv.) Melderis from Dutch coastal foredunes. This new species is characterized by the following characters: female with styler slightly curved dorsally, 13.3 mu m long, with large transversely ovoid kn

  18. Developmental and behavioural effects of the endophytic Fusarium moniliforme Fe14 towards Meloidogyne graminicola in rice

    NARCIS (Netherlands)

    Le, H.T.T.; Padgham, J.L.; Hagemann, M.H.; Sikora, R.A.; Schouten, Sander

    2016-01-01

    The root-knot nematode, Meloidogyne graminicola, is an important pest of rice in many rice production areas worldwide. The endophyte Fusarium moniliforme strain Fe14, isolated from a disinfected root of rice, has previously shown potential antagonistic activity against M. graminicola. This study

  19. Host susceptibility of tall fescue grass to Meloidogyne spp. and Mesocriconema xenoplax

    Science.gov (United States)

    Preplant fumigant nematicides have traditionally been used to control Meloidogyne spp. and Mesocriconema xenoplax in peach in the Southeast. In recent years growers have faced economic hardships, making it difficult to afford costs associated with these chemicals. Finding an alternative to control...

  20. Description of Meloidogyne panyuensis sp. n. (Nematoda: Meloidogynidae), parasitic on peanut (Arachis hypogaea L.) in China

    NARCIS (Netherlands)

    Liao, J.; Yang, W.; Feng, Z.; Karssen, G.

    2005-01-01

    Meloidogyne panyuensis n.sp. is described and illustrated from peanut, Arachis hypogaea L., in Guangdong, P.R.China. It is characterized by: female stylet of 13 mu m length, DGO of 10 mu m; perineal pattern ovoid to oval shaped, smooth to moderately coarse striae, dorsal arch relatively low, lateral

  1. Efeito de indutores de resistência sobre Meloidogyne exigua do cafeeiro Effect of resistance inducers on Meloidogyne exígua of coffee

    Directory of Open Access Journals (Sweden)

    Sônia Maria de Lima Salgado

    2007-08-01

    Full Text Available A possibilidade de manejo de Meloidogyne exigua Goeldi, 1887, pela ativação de mecanismos de defesa no cafeeiro representa uma alternativa potencialmente útil no manejo desse patógeno. Com este trabalho, objetivou-se avaliar a eclosão e mortalidade de juvenis do segundo estádio (J2 de M. exigua na presença de produtos indutores de resistência e avaliar o efeito do acibenzolar-S-metil (ASM, Bion® na indução de resistência do cafeeiro (Coffea arabica L. 'Catuaí- 144' contra M. exigua. A eclosão e mortalidade do J2 foram avaliadas no ASM e ácido salicílico (AS nas dosagens de 0,2; 0,35 e 0,5 g. i. a./L; e no fosfito de potássio (Hortifós® PK e silicato de potássio (Supa-potássio® nas dosagens 5,0; 7,5 e 10,0 mL/L, empregando água e aldicarbe como testemunhas. No segundo ensaio o ASM (0,2 g i.a./L foi aplicado na quantidade de 125 mL por planta de 'Catuaí-144' com um ano de idade, via pulverização foliar e diretamente ao solo aos 7 dias antes da inoculação e aos 2 e 7 dias após a inoculação de aproximadamente 7000 ovos de M. exigua/planta. Foram utilizadas 8 plantas/tratamento/bloco, totalizando 6 tratamentos (3 épocas de aplicação do ASM, testemunhas absoluta e inoculada, em 4 blocos. Aos 90 dias da inoculação, foi feita a avaliação da população final (número de ovos e juvenis de M. exigua, número de galhas, fator de reprodução (população final/população inicial e peso da matéria fresca da raiz. A dosagem dos produtos não influenciou a eclosão e mortalidade dos J2 de M. exigua. Menor eclosão dos J2 de M. exigua ocorreu igualmente no Supa-potássio® e ácido salicílico, enquanto que a eclosão no ASM e na água foi igual (P The parasitism of coffee roots by Meloidogyne exigua Goeldi, 1887, widespread nematode in the main producing regions, can provoke a series of modifications in the normal development of the plant. The induction of resistance for the activation of existing latent mechanisms of

  2. Waardplantgeschiktheid van roos voor het wortelknobbelaaltje Meloidogyne hapla : zeven M. hapla-isolaten, zes cultivars en een onderstam

    NARCIS (Netherlands)

    Amsing, J.J.; Beek, van der J.G.; Stapel, L.H.M.; Poleij, L.M.; Hok-A-Hin, C.H.; Zoon, F.C.

    2003-01-01

    Het noordelijk wortelknobbelaaltje, Meloidogyne hapla, wordt de laatste jaren steeds vaker aangetroffen in substraatteelten van roos. Onderzoek naar de schadelijkheid en populatieontwikkeling van dit wortelaaltje bij roos op substraat vereist de aanwezigheid van een vatbare cultivar of onderstam en

  3. Geschikte onderstammen voor biologisch geteelde komkommers, tomaten en paprika's in relatie tot wortelknobbelaaltjes (Meloidogyne spp.) - Resultaten onderzoek 2006-2010

    NARCIS (Netherlands)

    Janse, J.; Slooten, van M.A.; Wurff, van der A.W.G.

    2011-01-01

    Gedurende vijf achtereenvolgende jaren is door Wageningen UR Glastuinbouw onderzoek verricht naar geschikte onderstammen voor vruchtgroenten voor de biologische teelt in relatie tot wortelknobbelaaltjes (Meloidogyne spp.). Deze onderstammen mogen weinig wortelknobbels vertonen, een lage reproductie

  4. Dicty_cDB: Contig-U15170-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ) Molgula tectiformis cDNA, gastrula/neurula clone:... 46 2.6 1 ( BM882482 ) rb02b12.y1 Meloidogyne incognita egg pAMP1 Bird... M... 46 2.6 1 ( BM882351 ) ra99g01.y1 Meloidogyne incognita egg pAMP1 Bird M... 46 2.6 1 ( ...BM880516 ) rb23b12.y1 Meloidogyne incognita egg pAMP1 Bird M... 46 2.6 1 ( BM7748...72 ) ra98f07.y1 Meloidogyne incognita egg pAMP1 Bird M... 46 2.6 1 ( BM773831 ) ra86d08.y1 Meloidogyne incognita egg pAMP1 Bird... M... 46 2.6 1 ( BM773792 ) ra86a02.y1 Meloidogyne incognita egg pAMP1 Bird M... 46 2.6 1

  5. Dicty_cDB: Contig-U05323-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available Mel... 44 7.4 1 ( BM881676 ) rb12f10.y1 Meloidogyne incognita egg pAMP1 Bird M... 44 7.4 1 ( BM880894 ) rb19...d12.y1 Meloidogyne incognita egg pAMP1 Bird M... 44 7.4 1 ( BM880838 ) rb18g11.y1... Meloidogyne incognita egg pAMP1 Bird M... 44 7.4 1 ( BM774633 ) ra95h05.y1 Meloidogyne incognita egg pAMP1 Bird... M... 44 7.4 1 ( BM773926 ) ra87e01.y1 Meloidogyne incognita egg pAMP1 Bird M... 44 7.4 1 ( BM773896 ) r...a87b06.y1 Meloidogyne incognita egg pAMP1 Bird M... 44 7.4 1 ( BI746653 ) rm30a04

  6. Dicty_cDB: SSB550 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 0, *** SEQUENCING IN PROGRESS ***, 4 unordered pieces. 48 0.087 1 BM774742 |BM774742.1 ra97b02.y1 Meloidogyne incognita egg pAMP1 Bir...d Meloidogyne incognita cDNA 5', mRNA sequence. 44 1.4 1 AW571255 |AW571255.1 ra16b04.y2 Bird...s. 44 1.4 1 AW570934 |AW570934.1 ra13a02.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne incognita cDNA 5',... mRNA sequence. 44 1.4 1 BM880766 |BM880766.1 rb18a09.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne in...cognita cDNA 5', mRNA sequence. 44 1.4 1 AW570774 |AW570774.1 ra10g11.y1 Bird-Rao

  7. Dicty_cDB: Contig-U06283-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available Gossypium arboreum 7-10 dpa fiber ... 46 2.3 1 ( AW828708 ) ra73a06.y1 Bird-Rao M...eloidogyne incognita J2 Melo... 46 2.3 1 ( AW588731 ) ra03h10.y2 Bird-Rao Meloidogyne incognita J2 Melo... 4...6 2.3 1 ( AW571369 ) ra19f03.y2 Bird-Rao Meloidogyne incognita J2 Melo... 46 2.3 1 ( AW571332 ) ra19a06.y2 Bird...-Rao Meloidogyne incognita J2 Melo... 46 2.3 1 ( AW571277 ) ra16d05.y2 Bird-Ra...o Meloidogyne incognita J2 Melo... 46 2.3 1 ( AW571037 ) ra15d12.y1 Bird-Rao Meloidogyne incognita J2 Melo..

  8. Nematicidal Activity and Control Efficiency of Pyroligneous Liquor on Meloidogyne spp.%木醋液的杀线活性及对根结线虫病的防治效果研究

    Institute of Scientific and Technical Information of China (English)

    李维蛟; 李强; 胡先奇

    2009-01-01

    dilution ratio increased. Mortalities of J2 of four common root-knot nematodes, Meloidogyne hapla, M. arcnaria, M. incognita and M. javanica were 76.3%, 78.4%, 77.9% and 72.2%, respectively, at 72 hours after treatment with pyroligneous solution at 1:150 dilution ratio. Results from field studies indicated that pyrogenenous liquor and its powder were effective at controlling megranate root-knot nematode disease, with efficiencies of 63.9% and 50.5%, respectively. Pyroligneous liquor and its powder also had control efficiency on tomato root-knot nematode disease, in Xundian County were 54.1% and 28.6% respectively, and in Gejiu were 27.8% and 19.6%, respectively. [Conclusion] These results show that pyroligneous liquor has nematicidal activity on J2 of Meloidogyne spp. and control efficiency on megranate and tomato root-knot nematode diseases. The pyroligneous liquor is a kind of effective resource with expioitative prospect and potential application value in the field of root-knot nematode diseases control.

  9. Dicty_cDB: SLA431 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 0.y1 Meloidogyne incognita egg SL1 TOPO v1 ... 50 0.10 1 ( AW871346 ) ra76b02.y1 Bird-Rao Meloidogyne incogn...ita J2 Melo... 50 0.10 1 ( AW830042 ) ra48h09.y1 Bird-Rao Meloidogyne incognita J2 Melo... 50 0.10 1 ( AW828941 ) ra70a02.y1 Bird

  10. Efficacy of Carbofuran in Controlling Root-Knot Nematode (Meloidogyne javanica Whitehead, 1949 on Cultivars of Bambara Groundnut (Vigna subterranea (L. Verdc. in Yola, Nigeria

    Directory of Open Access Journals (Sweden)

    M. Y. Jada

    2011-01-01

    Full Text Available Bambara groundnut (Vigna subterrenea L. Verdc. is an important crop produced in Adamawa State of Nigeria. However, the production of the crop is seriously threatened by root-knot nematodes (RKNs; Meloidogyne spp.. Since cultural methods have not been very effective in controlling RKN, carbofuran was evaluated to determine its efficacy in controlling M. javanica in Yola during 2002 and 2003. Three bambara groundnut cultivars (Kwachanjiwa, Kwaheuma, and Kwatolotolo were evaluated using three application timings (at planting, 3 and 6 weeks after planting, and none. Results indicated that applying carbofuran at planting provided the greatest reduction in M. javanica population levels, which lead to increased yields in bambara groundnuts compared to the other two application timings. Furthermore, both Kwachanjiwa and Kwatolotolo provided similar high yields compared to Kwaheuma, which was most likely related to the M. javanica tolerance in these cultivars.

  11. Dicty_cDB: AFE706 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 1 ra95c11.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5' similar to TR:Q94272 Q94272 ...', mRNA sequence. 64 6e-08 2 AW827814 |AW827814.1 ra59b10.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne i...ncognita cDNA 5' similar to WP:K10C2.4 CE04750 FUMARYLACETOACETASE ;, mRNA sequence. 48 5e-07 3 AW871572 |AW871572.1 ra79e06.y1 Bird

  12. Genetic Mapping of Resistance to Meloidogyne arenaria in Arachis stenosperma: A New Source of Nematode Resistance for Peanut

    Science.gov (United States)

    Leal-Bertioli, Soraya C. M.; Moretzsohn, Márcio C.; Roberts, Philip A.; Ballén-Taborda, Carolina; Borba, Tereza C. O.; Valdisser, Paula A.; Vianello, Rosana P.; Araújo, Ana Cláudia G; Guimarães, Patricia M.; Bertioli, David J.

    2015-01-01

    Root-knot nematodes (RKN; Meloidogyne sp.) are a major threat to crops in tropical and subtropical regions worldwide. The use of resistant crop varieties is the preferred method of control because nematicides are expensive, and hazardous to humans and the environment. Peanut (Arachis hypogaea) is infected by four species of RKN, the most damaging being M. arenaria, and commercial cultivars rely on a single source of resistance. In this study, we genetically characterize RKN resistance of the wild Arachis species A. stenosperma using a population of 93 recombinant inbred lines developed from a cross between A. duranensis and A. stenosperma. Four quantitative trait loci (QTL) located on linkage groups 02, 04, and 09 strongly influenced nematode root galling and egg production. Drought-related, domestication and agronomically relevant traits were also evaluated, revealing several QTL. Using the newly available Arachis genome sequence, easy-to-use KASP (kompetitive allele specific PCR) markers linked to the newly identified RKN resistance loci were developed and validated in a tetraploid context. Therefore, we consider that A. stenosperma has high potential as a new source of RKN resistance in peanut breeding programs. PMID:26656152

  13. Genetic Mapping of Resistance to Meloidogyne arenaria in Arachis stenosperma: A New Source of Nematode Resistance for Peanut

    Directory of Open Access Journals (Sweden)

    Soraya C. M. Leal-Bertioli

    2016-02-01

    Full Text Available Root-knot nematodes (RKN; Meloidogyne sp. are a major threat to crops in tropical and subtropical regions worldwide. The use of resistant crop varieties is the preferred method of control because nematicides are expensive, and hazardous to humans and the environment. Peanut (Arachis hypogaea is infected by four species of RKN, the most damaging being M. arenaria, and commercial cultivars rely on a single source of resistance. In this study, we genetically characterize RKN resistance of the wild Arachis species A. stenosperma using a population of 93 recombinant inbred lines developed from a cross between A. duranensis and A. stenosperma. Four quantitative trait loci (QTL located on linkage groups 02, 04, and 09 strongly influenced nematode root galling and egg production. Drought-related, domestication and agronomically relevant traits were also evaluated, revealing several QTL. Using the newly available Arachis genome sequence, easy-to-use KASP (kompetitive allele specific PCR markers linked to the newly identified RKN resistance loci were developed and validated in a tetraploid context. Therefore, we consider that A. stenosperma has high potential as a new source of RKN resistance in peanut breeding programs.

  14. Site-Specific Management of Meloidogyne chitwoodi in Idaho Potatoes Using 1,3-Dichloropropene; Approach, Experiences, and Economics.

    Science.gov (United States)

    King, Bradley A; Taberna, John P

    2013-09-01

    Fumigation for nematode management in irrigated potato production systems of Idaho is widely practiced. Soil injection is the only labeled application method for 1,3-dichloropropene that is conventionally applied on a whole-field basis. Plant-parasitic nematode species exhibit spatially variable population densities that provide an opportunity to practice site-specific fumigation to reduce chemical usage and production costs. During 2002 to 2008, 62 fields intended for commercial potato production in eastern Idaho were sampled using a geo-referenced grid sampling system for plant-parasitic nematode population densities. In total, 4,030 grid samples were collected representing nearly 3,200 ha of commercial potato production. Collectively, 73% of the grid samples had Columbia root knot (CRN) (Meloidogyne chitwoodi) population densities below detectable levels. Site-specific fumigation is the practice of varying application rate of a fumigant based on nematode population density. In 2007, 640 ha of potato production were site-specific fumigated for CRN nematode control in eastern Idaho. On average, this practice resulted in a 30% reduction in chemical usage and production cost savings of $209/ha when 1,3-dichloropropene was used as the sole source of nematode suppression. Reductions in usage of 1,3-dichloropropene can exceed 50% if used in combination with a nonfumigant nematicide such as oxamyl. This combination approach can have production cost savings exceeding $200/ha. Based on farm-gate receipts and USDA inspections provided by potato producers from 2001 to 2011, potato tuber yield and quality have not been adversely affected using site-specific fumigation.

  15. First report on Meloidogyne chitwoodi hatching inhibition activity of essential oils and essential oils fractions

    OpenAIRE

    Faria, Jorge; Sena, Inês; Ribeiro, Bruno; Rodrigues, Ana Margarida; Maleita, Carla; Abrantes, Isabel; Bennett, Richard; Mota, Manuel; Figueiredo,Ana Cristina

    2015-01-01

    The Columbia root-knot nematode (CRKN), Meloidogyne chitwoodi, is an EPPO A2 type quarantine pest since 1998. This nematode causes severe damage in economically important crops such as potato and tomato, making agricultural products unacceptable for the fresh market and food processing. Commonly used nematicidal synthetic chemicals are often environmentally unsafe. Essential oils (EOs) may constitute safer alternatives against RKN. EOs, isolated from 56 plant samples, ...

  16. Reproduction of Meloidogyne javanica on Plant Roots Genetically Transformed by Agrobacterium rhizogenes

    OpenAIRE

    Verdejo, S.; Jaffee, B. A.; Mankau, R.

    1988-01-01

    Reproduction of Meloidogyne javanica was compared on several Agrobacterium rhizogenes-transformed root cultures under monoxenic conditions. M. javanica reproduced on all transformed roots tested; however, more females and eggs were obtained on potato and South Australian Early Dwarf Red tomato than on bindweed, Tropic tomato, lima bean, or carrot. Roots that grew at moderate rates into the agar and produced many secondary roots supported the highest reproduction. Numbers of females produced i...

  17. Impact of grapevine (Vitis vinifera) varieties on reproduction of the northern root-knot nematode (Meloidogyne hapla)

    Science.gov (United States)

    Plant-parasitic nematodes are microscopic soil worms that attack the roots of grape plants and cause yield loss. One of the most commonly encountered plant-parasitic nematodes in eastern Washington Vitis vinifera vineyards is Meloidogyne hapla, the northern root-knot nematode. The selection of plant...

  18. Meloidogyne luci n. sp. (Nematoda: Meloidogynidae), a root-knot nematode parasitising different crops in Brazil, Chile and Iran

    NARCIS (Netherlands)

    Carneiro, R.M.D.G.; Correa, V.R.; Almeida, M.R.A.; Gomes, A.C.M.M.; Deimi, A.M.; Castagnone-Sereno, P.; Karssen, G.

    2014-01-01

    A new root-knot nematode parasitising vegetables, flowers and fruits in Brazil, Iran and Chile, is described as Meloidogyne luci n. sp. The female has an oval to squarish perineal pattern with a low to moderately high dorsal arc and without shoulders, similar to M. ethiopica. The female stylet is ro

  19. RNA interference of effector gene Mc16D10L confers resistance against meloidogyne chitwoodi in arabidopsis and potato

    Science.gov (United States)

    Potatoes (Solanum tuberosum) are the most important non-cereal food crop. The Columbia root-knot nematode (Meloidogyne chitwoodi), a quarantine pathogen, is a significant problem in some of the major potato-producing areas worldwide. In spite of great genetic diversity in wild potato species, no com...

  20. A Taqman real-time PCR assay for detection of Meloidogyne hapla in root galls and in soil

    Science.gov (United States)

    Meloidogyne hapla is one of the most widespread and serious soil-borne nematodes causing root knot diseases in various crops. Early and accurate detection and quantification of M. hapla in soil is essential for effective disease management. The purpose of this study was to develop an assay for detec...

  1. Host status of six major weeds to Meloidogyne chitwoodi and Pratylenchus penetrans, including a preliminary field survey concerning other weeds

    NARCIS (Netherlands)

    Kutywayo, V.; Been, T.H.

    2006-01-01

    A glasshouse experiment was carried out to investigate the host status of six important weeds in intensive agricultural cropping systems to Meloidogyne chitwoodi and Pratylenchus penetrans. Senecio vulgaris L., Capsella bursa-pastoris (L.) Medic. and Solanum nigrum L. were hosts of M. chitwoodi with

  2. Specific diagnosis of two root-knot nematodes, Meloidogyne chitwoodi and M. fallax, with satellite DNA probes

    NARCIS (Netherlands)

    Castagnone-Sereno, P.; Leroy, F.; Bongiovanni, M.; Zijlstra, C.; Abad, P.

    1999-01-01

    Meloidogyne chitwoodi and M. fallax are serious pests of potato, and both species have been recently designated as quarantine organisms in the European Community and in Canada. The sympatric and less damaging species M. hapla is often found associated with both of them under temperate climates. Here

  3. Survey of Nematodes on Coffee in Hawaii

    OpenAIRE

    Schenck, S; Schmitt, D. P.

    1992-01-01

    Surveys of coffee fields in Hawaii during 1989-1991 indicated the presence of 10 nematode species in 8 genera. After coffee was planted in fields previously in sugarcane, populations of Criconemella sp. and Pratylenchus zeae gradually decreased, while Rotylenchulus reniformis and, in one field, Meloidogyne incognita, increased in numbers. Coffee is a poor host of R. reniformis, but weeds in coffee plantations may support this nematode. At present, nematodes pose no serious threat to Hawaii's ...

  4. Transcriptome analysis of root-knot nematode (Meloidogyne incognita)-infected tomato (Solanum lycopersicum) roots reveals complex gene expression profiles and metabolic networks of both host and nematode during susceptible and resistance responses

    DEFF Research Database (Denmark)

    Shukla, Neha; Yadav, Rachita; Kaur, Pritam

    2017-01-01

    plants and two infection time intervals from resistant plants, grown under soil conditions. Differentially expressed genes during susceptible (1827-tomato, 462-RKN) and resistance (25-tomato, 160-RKN) interactions were identified. In susceptible responses, tomato genes involved in cell wall structure......, development, primary and secondary metabolites and defense signalling pathways along with RKN genes involved in host parasitism, development and defense are discussed. In resistance responses, tomato genes involved in secondary metabolite and hormone-mediated defense responses along with RKN genes involved...... in starvation stress-induced apoptosis are discussed. Also, forty novel differentially expressed RKN genes encoding secretory proteins were identified. Our findings, for the first time, provide novel insights into temporal regulation of genes involved in various biological processes from tomato and RKN...

  5. Inhibitory effects of salicylic acid on Meloidogyne javanica reproduction in tomato plants

    Energy Technology Data Exchange (ETDEWEB)

    Moslemi, F.; Fatemy, S.; Bernard, F.

    2016-11-01

    Root-knot nematodes (Meloidogyne spp.), play a major role in loss of agricultural production. Natural substances, such as salicylic acid (SA) could possibly be involved in inducing host plant resistance against nematodes. The present study is concerned with exploring the effects of varying concentrations of SA as seed priming and soil drench on tomato growth parameters and the reproduction of the root-knot nematode Meloidogyne javanica. SA at 50 μM concentration caused only 2% of juvenile mortality under in vitro conditions. SA applied as 50 μM seed treatment caused 95% and, as a soil drench, 78% reduction in the number of egg masses that formed on tomato plants. The numbers of galls were reduced to a lesser extent. Final nematode density per gram of soil was reduced to less than 1 by the 50 μM SA seed treatment, and in other treatments decreased by between 70 and 88% compared with control plants. Our results indicate SA has potential to lower root knot nematode reproduction in tomato, and seed priming is a fairly easy method to work with. (Author)

  6. Inhibitory effects of salicylic acid on Meloidogyne javanica reproduction in tomato plants

    Directory of Open Access Journals (Sweden)

    Seddigheh Fatemy

    2016-03-01

    Full Text Available Root-knot nematodes (Meloidogyne spp., play a major role in loss of agricultural production. Natural substances, such as salicylic acid (SA could possibly be involved in inducing host plant resistance against nematodes. The present study is concerned with exploring the effects of varying concentrations of SA as seed priming and soil drench on tomato growth parameters and the reproduction of the root-knot nematode Meloidogyne javanica. SA at 50 μM concentration caused only 2% of juvenile mortality under in vitro conditions. SA applied as 50 μM seed treatment caused 95% and, as a soil drench, 78% reduction in the number of egg masses that formed on tomato plants. The numbers of galls were reduced to a lesser extent. Final nematode density per gram of soil was reduced to less than 1 by the 50 μM SA seed treatment, and in other treatments decreased by between 70 and 88% compared with control plants. Our results indicate SA has potential to lower root knot nematode reproduction in tomato, and seed priming is a fairly easy method to work with.

  7. Dicty_cDB: VSC358 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available complete sequence. 44 0.075 6 AW828708 |AW828708.1 ra73a06.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne ...incognita cDNA 5', mRNA sequence. 46 0.43 1 AW571037 |AW571037.1 ra15d12.y1 Bird-Rao Meloidogyne incognita J...Gossypium arboreum cDNA clone GA__Ea0006G06f, mRNA sequence. 46 0.43 1 AW588731 |AW588731.1 ra03h10.y2 Bird-...ponicum cDNA, mRNA sequence. 46 0.43 1 AW571277 |AW571277.1 ra16d05.y2 Bird-Rao Meloidogyne incognita J2 Mel...oidogyne incognita cDNA 5', mRNA sequence. 46 0.43 1 AW571332 |AW571332.1 ra19a06.y2 Bird

  8. Dicty_cDB: Contig-U02317-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ) rb18a09.y1 Meloidogyne incognita egg pAMP1 Bird M... 44 8.1 1 ( BM774742 ) ra97b02.y1 Meloidogyne incognita egg pAMP1 Bird... M... 44 8.1 1 ( AW571311 ) ra16g10.y2 Bird-Rao Meloidogyne incognita J2 Melo... 44 8.1 1 (... AW571255 ) ra16b04.y2 Bird-Rao Meloidogyne incognita J2 Melo... 44 8.1 1 ( AW570934 ) ra13a02.y1 Bird...-Rao Meloidogyne incognita J2 Melo... 44 8.1 1 ( AW570774 ) ra10g11.y1 Bird-Rao Meloido

  9. Dicty_cDB: SSM635 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 23061 |BX323061.6 Mouse DNA sequence from clone RP24-267L10 on chromosome 11. 46 0.45 1 AW570934 |AW570934.1 ra13a02.y1 Bird... pieces. 44 1.8 1 AW571311 |AW571311.1 ra16g10.y2 Bird-Rao Meloidogyne incognita J2 Meloidogyne incognita cD...NA 5', mRNA sequence. 44 1.8 1 AW571255 |AW571255.1 ra16b04.y2 Bird-Rao Meloidogy...dogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5', mRNA sequence. 44 1.8 1 AC011836 |AC011836.3 ...ordered pieces. 44 1.8 1 BM880766 |BM880766.1 rb18a09.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne in

  10. Dicty_cDB: SLH306 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 35 ) rm36d04.y1 Meloidogyne arenaria egg pAMP1 v1 Chia... 72 8e-23 3 ( BM774794 ) ra97g03.y1 Meloidogyne incognita egg pAMP1 Bird... M... 72 8e-23 3 ( BM773715 ) ra85b05.y1 Meloidogyne incognita egg pAMP1 Bird... M... 72 2e-20 3 ( BM881593 ) rb11g01.y1 Meloidogyne incognita egg pAMP1 Bird M... 58 1e-18

  11. First record of the root knot nematode, Meloidogyne minor in New Zealand with description, sequencing information and key to known species of Meloidogyne in New Zealand.

    Science.gov (United States)

    Zhao, Zeng Qi; Ho, Wellcome; Griffin, Ruth; Surrey, Michael; Taylor, Robert; Aalders, Lee T; Bell, Nigel L; Xu, Yu Mei; Alexander, Brett J R

    2017-02-09

    Meloidogyne minor Karssen et al. 2004 was collected from perennial ryegrass (Lolium perenne L.) growing in a sports ground in Christchurch, New Zealand. This is a new record for M. minor, the first report of this nematode occurring in New Zealand, and the second report from the southern hemisphere (after Chile). In general, the New Zealand isolate of M. minor corresponds well to the descriptions of M. minor given by Karssen et al. (2004). The New Zealand isolate is characterized by having a female with dorsally curved stylet, 13-14 μm long, with transversely ovoid knobs slightly sloping backwards from shaft; rounded perineal pattern; and male with stylet 16-19 μm long, large transversely ovoid knobs sloping slightly backwards from shaft; head region not set off, labial disc elevated, lateral lips prominent; and second stage juvenile 370-390 μm long, with hemizonid posterior but adjacent to excretory pore; tail 53-63 μm long; and a distinct hyaline tail terminus 14-18 μm long. In addition, molecular phylogeny using near full length small subunit (SSU), D2/D3 expansion segments of the large subunit (LSU), the internal transcribed spacer region (ITS1 and 2), and the intergenic spacer (IGS2) of the ribosomal rDNA supports the identification.

  12. Dicty_cDB: SLK896 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ASSEMBLY PROTEIN AP47 ;, mRNA sequence. 54 4e-09 2 BM774869 |BM774869.1 ra98f03.y1 Meloidogyne incognita egg pAMP1 Bird...RNA sequence. 58 2e-08 2 BM880852 |BM880852.1 rb19a03.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne in

  13. Dicty_cDB: SSD517 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available eba histolytica genomic, DNA sequence. 56 2e-06 2 AW570895 |AW570895.1 ra12e05.y1 Bird-Rao Meloidogyne incog...NTEP18TR Entamoeba histolytica Sheared DNA Entamoeba histolytica genomic, DNA sequence. 56 5e-04 1 AW588730 ...|AW588730.1 ra03h09.y2 Bird-Rao Meloidogyne incognita J2 Meloidogyne incognita cDNA 5' similar to WP:F55H2.2

  14. Cellular Responses of Resistant and Susceptible Soybean Genotypes Infected with Meloidogyne arenaria Races 1 and 2.

    Science.gov (United States)

    Pedrosa, E M; Hussey, R S; Boerma, H R

    1996-06-01

    The cellular responses induced by Meloidogyne arenaria races 1 and 2 in three soybean genotypes, susceptible CNS, resistant Jackson, and resistant PI 200538, were examined by light microscopy 20 days after inoculation. Differences in giant-cell development were greater between races than among the soybean genotypes. M. arenaria race 1 stimulated small, poorly formed giant-cells in contrast with M. arenaria race 2, which induced well-developed, thick-walled, multinucleate giant-cells. The number of nuclei per giant-celt was variable, but fewer nuclei were usually present in giant-cells induced by race 1 (mean 16 nuclei) than in giant-cells induced by race 2 (mean 41 nuclei). Differences observed in giant-cell development were related to differences in growth and maturation of M. arenaria races 1 and 2 and host suitability of the soybean genotypes.

  15. Efficacy of Fumigant and Nonfurmigant Nematicides for Control of Meloidogyne arenaria on Peanut.

    Science.gov (United States)

    Dickson, D W; Hewlett, T E

    1988-10-01

    Three tests were conducted to evaluate the efficacy of fumigant and nonfumigant nematicides for control of Meloidogyne arenaria race 1 on peanut. Methyl bromide, 1,3-D, methyl isothiocyanate, and methyl isothiocyanate mixtures were applied 7 or 8 days preplant either broadcast or in-the-row. Aldicarb, ethoprop, fenamiphos, and F5145 were applied at different rates and by different methods at-plant or at early flowering. Of the 32 treatments evaluated, only seven resulted in yield increases (P = 0.05), although early season vigor was high in all treated plots. During the latter one-third of the growing season, however, nematode control was not adequate in most treatments resulting in heavy peg, pod, and root infection by M. arenaria.

  16. Root-knot Nematode Management and Yield of Soybean as Affected by Winter Cover Crops, Tillage Systems, and Nematicides.

    Science.gov (United States)

    Minton, N A; Parker, M B

    1987-01-01

    Management of Meloidogyne incognita on soybean as affected by winter small grain crops or fallow, two tillage systems, and nematicides was studied. Numbers of M. incognita did not differ in plots planted to wheat and rye. Yields of soybean planted after these crops also did not differ. Numbers of M. incognita were greater in fallow than in rye plots, but soybean yield was not affected by the two treatments. Soybean yields were greater in subsoil-plant than in moldboard plowed plots. Ethylene dibromide reduced nematode population densities more consistently than aldicarb and phenamiphos. Also, ethylene dibromide increased yields the most and phenamiphos the least. There was a positive correlation (P = 0.001) of seed size (weight of 100 seeds) with yield (r = 0.79), indicating that factors affecting yield also affected seed size.

  17. The complex hybrid origins of the root knot nematodes revealed through comparative genomics

    Directory of Open Access Journals (Sweden)

    David H. Lunt

    2014-05-01

    Full Text Available Root knot nematodes (RKN can infect most of the world’s agricultural crop species and are among the most important of all plant pathogens. As yet however we have little understanding of their origins or the genomic basis of their extreme polyphagy. The most damaging pathogens reproduce by obligatory mitotic parthenogenesis and it has been suggested that these species originated from interspecific hybridizations between unknown parental taxa. We have sequenced the genome of the diploid meiotic parthenogen Meloidogyne floridensis, and use a comparative genomic approach to test the hypothesis that this species was involved in the hybrid origin of the tropical mitotic parthenogen Meloidogyne incognita. Phylogenomic analysis of gene families from M. floridensis, M. incognita and an outgroup species Meloidogyne hapla was carried out to trace the evolutionary history of these species’ genomes, and we demonstrate that M. floridensis was one of the parental species in the hybrid origins of M. incognita. Analysis of the M. floridensis genome itself revealed many gene loci present in divergent copies, as they are in M. incognita, indicating that it too had a hybrid origin. The triploid M. incognita is shown to be a complex double-hybrid between M. floridensis and a third, unidentified, parent. The agriculturally important RKN have very complex origins involving the mixing of several parental genomes by hybridization and their extreme polyphagy and success in agricultural environments may be related to this hybridization, producing transgressive variation on which natural selection can act. It is now clear that studying RKN variation via individual marker loci may fail due to the species’ convoluted origins, and multi-species population genomics is essential to understand the hybrid diversity and adaptive variation of this important species complex. This comparative genomic analysis provides a compelling example of the importance and complexity of

  18. Identification of Root-knot Nematodes on Trichosanthes spp.in Jiangsu%江苏省瓜蒌根结线虫种类鉴定

    Institute of Scientific and Technical Information of China (English)

    赵雷; 张红艳; 万景旺; 叶小云; 蒋祝成; 程兆榜; 周益军; 魏利辉

    2012-01-01

    本文对江苏瓜萎上根结线虫样本进行广泛采集,单卵块纯化培养后,运用形态学方法和分子生物学方法对其进行了鉴定.根据雌虫会阴花纹、雌虫、雄虫和2龄幼虫的相关测量值等形态学鉴定特征,并结合特异引物的PCR扩增图谱,鉴定出该病原为南方根结线虫(Meloidogyne incognita).结果表明,江苏省瓜萎根结线虫群体类型为南方根结线虫,将进一步为该病害传播、流行和控制提供可行的理论依据.%In this paper, Meloidagyne populations on Trichosanthes spp. were collected and purified in Jisngsu. Based on diagnostic characters and morphometrics of females, males, and second-stage juveniles, the perineal patterns of female, using molecular biological techniques , the root-knot nematodes isolated from Trichasanthes were identified as Meloidogyne incognita with morphology and molecular biology. The results showed that the identification of Trichosanthes spp. which occurred on in Jiangsu was Meloidogyne incognita,which would provid theoretical basis for control of the root-knot nematodes disease.

  19. In vitro co-culture of Solanum tuberosum hairy roots with Meloidogyne chitwoodi: structure, growth and production of volatiles

    OpenAIRE

    Faria, JMS; Sena, I.; Maleita, CM; Vieira, I; Ascenção, L; Abrantes, Isabel; Bennett, RN; Mota, Manuel; Figueiredo, AC.

    2014-01-01

    Meloidogyne spp., commonly known as root- knot nematodes (RKNs), are economically important plant sedentary endoparasites that cause galls on susceptible hosts. The Columbia root-knot nematode (CRKN), M. chitwoodi, is a quarantine A2 type pest by the European and Mediterranean Plant Protection Organization since 1998. This nematode has been found associated with economi- cally important crops such as potato and tomato, causing severe damage and making the agricultural products unac- ceptable ...

  20. Long-Term Effect of Crop Rotation on Soybean in a Field Infested with Meloidogyne arenaria and Heterodera glycines

    OpenAIRE

    Weaver, D. B.; Rodríguez-Kábana, R.; Carden, E. L.

    1989-01-01

    Previous cropping sequence (corn-soybean vs. soybean-soybean) and aldicarb effects on soybean yield and nematode numbers at harvest for soybean cultivars with various combinations of nematode resistance were determined in 1988 in a sandy loam soil infested with Meloidogyne arenaria race 2 and Heterodera glycines races 3 and 4 at Elberta, Alabama. Yield and nematode numbers differed among cultivars with 'Leflore' having the highest yield. Aldicarb treatment resulted in increased soybean yield ...

  1. Comparison of saline tolerance among genetically similar species of Fusarium and Meloidogyne recovered from marine and terrestrial habitats

    Science.gov (United States)

    Elmer, W. H.; LaMondia, J. A.

    2014-08-01

    Successful plant pathogens co-evolve and adapt to the environmental constraints placed on host plants. We compared the salt tolerance of two salt marsh pathogens, Fusarium palustre and Meloidogyne spartinae, to genetically related terrestrial species, F. sporotrichioides and Meloidogyne hapla, to assess whether the salt marsh species had acquired selective traits for persisting in saline environments or if salt tolerance was comparable among Fusarium and Meloidogyne species. Comparisons of both species were made in vitro in vessels containing increasing concentration of NaCl. We observed that F. palustre was more tolerant to NaCl than F. sporotrichioides. The radial expansion of F. palustre on NaCl-amended agar plates was unaffected by increasing concentrations up to 0.3 M. F. sporotrichioides showed large reductions in growth at the same concentrations. Survival of M. hapla was greatest at 0 M, and reduced by half in a 0.3 M solution for 4 days. No juveniles survived exposure to 0.3 M NaCl for 12 days. M. spartinae survived at all NaCl concentrations tested, including 1.0 M for at least 12 days. These findings are consistent with the hypothesis that marine organisms in the upper tidal zone must osmoregulate to withstand a wide range of salinity and provide evidence that these pathogens evolved in saline conditions and are not recent introductions from terrestrial niches.

  2. Resistência do cafeeiro a nematóides: I - Testes em progênies e híbridos, para Meloidogyne exigua Coffee breeding for resistance to Meloidogyne exigua: I - Screening test using arabica progenies and interespecific hybrids

    Directory of Open Access Journals (Sweden)

    L. C. Fazuoli

    1977-01-01

    Full Text Available Procurou-se identificar fontes de resistência ao nematóide Meloidogyne exígua em cafeeiros derivados de híbridos interespecíficos e em progênies de café arábica oriundas da Etiópia, em experimentos estabelecidos em duas localidades. A infestação foi feita por dois processos usados com freqüência nesse tipo de trabalho. As avaliações do grau de ataque foram feitas quatro e 12 meses após a infestação, em Campinas e Ribeirão Preto, respectivamente, adotando-se escala variando de zero, para ausência de galhas, a cinco pontos para grande intensidade de ataque. Verificou-se que a leitura feita aos quatro meses é tão eficiente quanto aos 12 meses, indicando a possibilidade de abreviar consideravelmente a duração dessas avaliações. Notou-se, no experimento de Ribeirão Preto, uma redução de aproximadamente 8% no crescimento das mudas infestadas e verificou-se, também, uma redução de 11,5% e 12% nos pesos verde e seco das plantas, devido ao ataque do nematóide. De 1.692 plantas examinadas nos dois experimentos, selecionaram-se 106 (6,3%, caracterizadas pela ausência de galhas. As populações derivadas dos híbridos entre Coffea arabica e C. canephora revelaram-se mais promissoras, contribuindo com maior número de plantas resistentes. As plantas do experimento instalado em Campinas foram inoculadas também com a raça II de Hemileia vastatrix para o estudo da resistência conjunta aos dois patógenos. Essas seleções, em número de 38, representam valioso material para o programa de melhoramento do cafeeiro.Two coffee screening tests were undertaken in order to find out sources of resistance to the nematode M. exigua. Arabica progenies from Ethiopia origin and advanced popu-lations derived from interspecific crosses (Coffea arabica x C. canephora and C. arabica x C. dewevrei were evaluated. A five point scale (0 point to the roots without galls and 5 points to severely attacked roots was used for determination of the

  3. Alterações anatômicas induzidas por Meloidogyne enterolobii (=M. mayaguensis e Meloidogyne javanica em tomateiros resistentes a meloidoginose

    Directory of Open Access Journals (Sweden)

    Juliana Nogueira Westerich

    2012-09-01

    Full Text Available A resistência de tomateiros (Solanum lycopersicum L. a M. incognita, M. javanica e M. arenaria, conferida pela presença do gene Mi, não contempla a espécie M. enterolobii (=M. mayaguensis. O objetivo da pesquisa foi verificar as alterações anatômicas causadas por M. enterolobii no sistema radicular de porta-enxertos de tomateiro com o gene de resistência Mi ('Magnet' e Helper M' e compará-las com as causadas por M. javanica. As observações anatômicas das raízes foram feitas com auxílio de microscópio de luz e os aspectos mais relevantes foram fotografados. Com base em contagens e mensurações do tamanho dos sítios de alimentação e das células gigantes, foram efetuadas analises utilizando o método estatístico de Análise de Agrupamento. O aparecimento de células nutridoras incitadas por M. enterolobii foi verificado em ambos os porta-enxertos de tomateiro, entre 10 e 17 dias após a inoculação (DAI. O número e a área de sítios de alimentação e de células gigantes foram menores aos 17 DAI do que aos 24 DAI. Nesta época (24 DAI, foram observados sítios de alimentação constituídos pela presença de várias células nutridoras multinucleadas, com parede celular espessa, citoplasma denso e granuloso. Os tecidos vasculares apresentaram-se comprimidos e desorganizados, foi observada, também, hipertrofia de células do parênquima cortical. As raízes inoculadas com M. javanica não apresentaram alterações anatômicas.

  4. Responses of tomato genotypes to avirulent and Mi-virulent Meloidogyne javanica isolates occurring in Israel.

    Science.gov (United States)

    Iberkleid, Ionit; Ozalvo, Rachel; Feldman, Lidia; Elbaz, Moshe; Patricia, Bucki; Horowitz, Sigal Brown

    2014-05-01

    The behavior of naturally virulent Meloidogyne isolates toward the tomato resistance gene Mi in major tomato-growing areas in Israel was studied for the first time. Virulence of seven selected isolates was confirmed over three successive generations on resistant (Mi-carrying) and susceptible (non-Mi-carrying) tomato cultivars. Diagnostic markers verified the predominance of Meloidogyne javanica among virulent isolates selected on resistant tomato cultivars or rootstocks. To better understand the determinants of nematode selection on Mi-carrying plants, reproduction of Mi-avirulent and virulent isolates Mjav1 and Mjv2, respectively, measured as eggs per gram of root, on non-Mi-carrying, heterozygous (Mi/mi) and homozygous (Mi/Mi) genotypes was evaluated. Although no reproduction of Mjav1 was observed on Mi/Mi genotypes, some reproduction was consistently observed on Mi/mi plants; reproduction of Mjv2 on the homozygous and heterozygous genotypes was similar to that on susceptible cultivars, suggesting a limited quantitative effect of the Mi gene. Histological examination of giant cells induced by Mi-virulent versus avirulent isolates confirmed the high virulence of Mjv2 on Mi/mi and Mi/Mi genotypes, allowing the formation of well-developed giant-cell systems despite the Mi gene. Analysis of the plant defense response in tomato Mi/Mi, Mi/mi, and mi/mi genotypes to both avirulent and virulent isolates was investigated by quantitative real-time polymerase chain reaction. Although the jasmonate (JA)-signaling pathway was clearly upregulated by avirulent and virulent isolates on the susceptible (not carrying Mi) and heterozygous (Mi/mi) plants, no change in signaling was observed in the homozygous (Mi/Mi) resistant line following incompatible interaction with the avirulent isolate. Thus, similar to infection promoted by the avirulent isolate on the susceptible genotype, the Mi-virulent isolate induced the JA-dependent pathway, which might promote tomato susceptibility

  5. Role of nematodes, nematicides, and crop rotation on the productivity and quality of potato, sweet potato, peanut, and grain sorghum.

    Science.gov (United States)

    Johnson, A W; Dowler, C C; Glaze, N C; Handoo, Z A

    1996-09-01

    The objective of this experiment was to determine the effects of fenamiphos 15G and short-cycle potato (PO)-sweet potato (SP) grown continuously and in rotation with peanut (PE)-grain sorghum (GS) on yield, crop quality, and mixed nematode population densities of Meloidogyne arenaria, M. hapla, M. incognita, and Mesocriconema ornatum. Greater root-gall indices and damage by M. hapla and M. incognita occurred on potato than other crops. Most crop yields were higher and root-gall indices lower from fenamiphos-treated plots than untreated plots. The total yield of potato in the PO-SP and PO-SP-PE-GS sequences increased from 1983 to 1985 in plots infested with M. hapla or M. arenaria and M. incognita in combination and decreased in 1986 to 1987 when root-knot nematode populations shifted to M. incognita. The total yields of sweet potato in the PO-SP-PE-GS sequence were similar in 1983 and 1985, and declined each year in the PO-SP sequence as a consequence of M. incognita population density increase in the soil. Yield of peanut from soil infested with M. hapla increased 82% in fenamiphos-treated plots compared to untreated plots. Fenamiphos treatment increased yield of grain sorghum from 5% to 45% over untreated controls. The declining yields of potato and sweet potato observed with both the PO-SP and PO-SP-PE-GS sequences indicate that these crop systems should not be used longer than 3 years in soil infested with M. incognita, M. arenaria, or M. hapla. Under these conditions, these two cropping systems promote a population shift in favor of M. incognita, which is more damaging to potato and sweet potato than M. arenaria and M. hapla.

  6. Meloidogyne platani n. sp. (Meloidogynidae), a Root-knot Nematode Parasitizing American Sycamore.

    Science.gov (United States)

    Hirschmann, H

    1982-01-01

    Meloidogyne platani n. sp. is described and illustrated from specimens obtained from roots of American sycamore, Platanus occidentalis, in Virginia. This new species shows certain similarities with M. arenaria but differs from it by a number of distinctive characters. The perineal pattern of females is rounded with fine, wavy to zig-zag striae and raised, convoluted striae in the inner lateral line regions. The stylet of females is 16.5 mum long with large, rounded stylet knobs set off from the shaft. Males have a low head cap and smooth head region. The styler length is 22.0 mum, and the stylet knobs are rounded and set off from the shaft. Mean second-stage juvenile length is 443.0 mum, and stylet length is 12.2 mum. The head region of juveniles is not annulated, and the tail has a definite terminus. This nematode causes severe galling and reproduces well on sycamore. Other good hosts include white ash and tobacco cv. NC 95. M. platani n. sp. reproduces by mitotic parthenogenesis and has a somatic chromosome number of approximately 45 (2n).

  7. ParasiticMeloidogyne and mutualisticAcremonium increase chitinase in tall fescue.

    Science.gov (United States)

    Roberts, C A; Marek, S M; Niblack, T L; Karr, A L

    1992-07-01

    Tall fescue (Festuca arundinacea Schreb.) is a C-3 perennial grass noted for its persistence in harsh environments. Tall fescue persistence is enhanced byAcremonium coenophialum, a mutualistic fungal endophyte that increases resistance to drought, pathogens, and insects. This research was conducted to identify and elicit biochemical mechanism(s) that could account for tall fescue persistence. In initial studies, two cultivars known to differ in persistence were analyzed for chitinase, an antifungal hydrolase associated with disease resistance in other plants.Acremonium-infected Kentucky 31 (KY31), a persistent cultivar, and Johnstone, a nonpersistent cultivar, were inoculated with the parasitic nematode,Meloidogyne marylandi, grown for 50 days, and analyzed at 10-day intervals. Chitinase fluctuated throughout the 50-day period of seedling development, and activity was highest in the persistentAcremonium-infected KY31. In addition, chitinase was elicited by parasiticM. marylandi and expressed systemically. Subsequent studies were conducted to determine whether or not mutualisticAcremonium could increase chitinase activity. Genetically identical KY31, with and withoutAcremonium, were grown for 25 days and analyzed for chitinase at 5-day intervals. After 20 days,Acremonium-infected KY31 expressed more chitinase thanAcremonium-free KY31. We concluded that chitinase is related to tall fescue persistence; it was highest in the most persistent cultivar, increased under pathogen attack, and increased in the presence ofAcremonium, a symbiont known to enhance disease resistance.

  8. Control of Meloidogyne javanica by Formulations of Inula viscosa Leaf Extracts.

    Science.gov (United States)

    Oka, Yuji; Ben-Daniel, Bat-Hen; Cohen, Yigal

    2006-03-01

    Inula viscosa is a perennial plant that is widely distributed in Mediterranean countries. Formulations of I. viscosa extracts were tested for their effectiveness in control of Meloidogyne javanica in laboratory, growth chamber, microplot, and field experiments. Oily pastes were obtained by extraction of dry leaves with a mixture of acetone and n-hexane or n-hexane alone, followed by evaporation of the solvents. Emulsifiable concentrate formulations of the pastes killed M. javanica juveniles in sand at a concentration of 0.01% (paste, w/w) or greater and reduced the galling index of cucumber seedlings as well as the galling index and numbers of nematode eggs on tomato plants in growth chamber experiments. In microplot experiments, the hexane-extract formulation at 26 g paste/m(2) reduced nematode infection on tomato plants in one of two experiments. In a field experiment, a reduction of 40% in root galling index by one of two formulations was observed on lettuce plants. The plant extracts have potential as a natural nematicide, although the formulations need improvement.

  9. Detecção de Meloidogyne enterolobii em mudas de amoreira (Morus nigra L.

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    Vanessa dos Santos Paes-Takahashi

    2015-05-01

    Full Text Available O comércio de mudas sem certificação contribui para disseminação de pragas e doenças, que podem causar sérios danos às plantas cultivadas. Na região de Itapetininga (SP, foram apreendidas, pela equipe da Defesa Agropecuária, mudas de aceroleira, goiabeira e amoreira, comercializadas em caminhões, que apresentavam galhas nas raízes, sintoma típico causado por Meloidogyne spp. A identificação da espécie foi feita através da morfologia da configuração perineal de fêmeas e região labial de machos, bem como através da caracterização do fenótipo enzimático de esterase. Foi constatada a presença de M. enterolobii nas amostras analisadas. Trata-se do primeiro relato do parasitismo de M. enterolobii em mudas de amoreira no mundo.

  10. The nematicidal effect of camellia seed cake on root-knot nematode Meloidogyne javanica of banana.

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    Xiujuan Yang

    Full Text Available Suppression of root-knot nematodes is crucially important for maintaining the worldwide development of the banana industry. Growing concerns about human and environmental safety have led to the withdrawal of commonly used nematicides and soil fumigants, thus motivating the development of alternative nematode management strategies. In this study, Meloidogyne javanica was isolated, and the nematicidal effect of Camellia seed cake on this pest was investigated. The results showed that in dish experiments, Camellia seed cake extracts under low concentration (2 g/L showed a strong nematicidal effect. After treatment for 72 h, the eggs of M. javanica were gradually dissolved, and the intestine of the juveniles gradually became indistinct. Nematicidal compounds, including saponins identified by HPLC-ESI-MS and 8 types of volatile compounds identified by GC-MS, exhibited effective nematicidal activities, especially 4-methylphenol. The pot experiments demonstrated that the application of Camellia seed cake suppressed M. javanica, and promoted the banana plant growth. This study explored an effective nematicidal agent for application in soil and revealed its potential mechanism of nematode suppression.

  11. Control of Meloidogyne chitwoodi in Potato with Fumigant and Nonfumigant Nematicides.

    Science.gov (United States)

    Ingham, R E; Hamm, P B; Williams, R E; Swanson, W H

    2000-12-01

    During 1993-94, several fumigant and nonfumigant nematicides were tested alone and in combination at various rates for control of Columbia root-knot nematode (Meloidogyne chitwoodi) in potato. Ethoprop, oxamyl, or metam sodium alone did not adequately reduce tuber infection. Metam sodium plus ethoprop reduced culled tubers to 3%, and metam sodium plus 2 or 3 foliar applications of oxamyl reduced culls to

  12. Comparison of Fumigant and Nonfumigant Nematicides for control of Meloidogyne chitwoodi on Potato.

    Science.gov (United States)

    Griffin, G D

    1989-10-01

    The fumigant 1,3-dichloropropene (1,3-D) effectively controlled Meloidogyne chitwoodi on Russet Burbank potato, Solanum tuberosum. There was a maximum of 4% infected and galled tubers from the 1,3-D treatment after 2,028 degree-days with a base temperature of 5 C (DD5). This compared to 66% infected and galled tubers in aldicarb at-plant treated plots. Soil temperature, as determined by DD5, and timing of chemical applications affected the nematicidal activity on M. chitwoodi (P < 0.05). Aldicarb was most effective when applied postplant (PP) during the nematode reproductive cycle. After 1,684 DD5 of growth, there were 59, 26, 22, and 6% infected and galled tubers from untreated control plots and aldicarb treatments of 2.1 g/m row at 600 DD5, 2.1 g/m row at 1,228 DD5, and 1.3 g/m row at 600 DD5 plus 2.1 g/m row at 1,228 DD5, respectively. No aldicarb treatments were effective over a growing period of 2,028 DD5; 34% of the tubers were infected and galled following the most effective aldicarb treatment (1.3 g/m row at 504 DD5 plus 2.1 g/m row at 996 DD5).

  13. The Nematicidal Effect of Camellia Seed Cake on Root-Knot Nematode Meloidogyne javanica of Banana

    Science.gov (United States)

    Yang, Xiujuan; Wang, Xuan; Wang, Kang; Su, Lanxi; Li, Hongmei; Li, Rong; Shen, Qirong

    2015-01-01

    Suppression of root-knot nematodes is crucially important for maintaining the worldwide development of the banana industry. Growing concerns about human and environmental safety have led to the withdrawal of commonly used nematicides and soil fumigants, thus motivating the development of alternative nematode management strategies. In this study, Meloidogyne javanica was isolated, and the nematicidal effect of Camellia seed cake on this pest was investigated. The results showed that in dish experiments, Camellia seed cake extracts under low concentration (2 g/L) showed a strong nematicidal effect. After treatment for 72 h, the eggs of M. javanica were gradually dissolved, and the intestine of the juveniles gradually became indistinct. Nematicidal compounds, including saponins identified by HPLC-ESI-MS and 8 types of volatile compounds identified by GC-MS, exhibited effective nematicidal activities, especially 4-methylphenol. The pot experiments demonstrated that the application of Camellia seed cake suppressed M. javanica, and promoted the banana plant growth. This study explored an effective nematicidal agent for application in soil and revealed its potential mechanism of nematode suppression. PMID:25849382

  14. Optimum Concentrations of Trichoderma longibrachiatum and Cadusafos for Controlling Meloidogyne javanica on Zucchini Plants

    Science.gov (United States)

    Sokhandani, Zahra; Moosavi, Mohammad Reza; Basirnia, Tahereh

    2016-01-01

    A factorial experiment was established in a completely randomized design to verify the effect of different inoculum levels of an Iranian isolate of Trichoderma longibrachiatum separately and in combination with various concentrations of cadusafos against Meloidogyne javanica in the greenhouse. Zucchini seeds were soaked for 12 hr in five densities (0, 105, 106, 107, and 108 spores/ml suspension) of the fungus prior to planting in pots containing four concentrations of cadusafos (0, 0.5, 1, and 2 mg a.i./kg soil). The data were analyzed using a custom response surface regression model and the response surface curve and contour plots were drawn. Reliability of the model was examined by comparing the result of new experimental treatments with the predicted results. The optimal levels of these two variables also were calculated. The interactive effects of concentrations of Trichoderma and cadusafos were insignificant for several responses such as the total number of eggs per gram soil, the number of intact eggs per gram soil, nematode reproduction factor, and control percent. Closeness of experimental mean values with the expected values proved the validity of the model. The optimal levels of the cadusafos concentration and Trichoderma concentration that caused the best plant growth and lowest nematode reproduction were 1.7 mg a.i./kg soil and 108 conidia/ml suspension, respectively. PMID:27168653

  15. Greenhouse and field assessment of different organic compounds against guava-parasitic Meloidogyne enterolobii

    Directory of Open Access Journals (Sweden)

    Alexandre Macedo Almeida

    2012-01-01

    Full Text Available Guava decline is a complex disease involving Meloidogyne enterolobii and Fusarium solani and it has caused major direct losses to Brazilian growers. Although several strategies have been sought to control the nematode, the use of organic soil amendments is currently the best approach to manage this disease. To assess the best amount of meat and bone meal (MBM to be incorporated into the soil, guava seedlings inoculated with M. enterolobii were treated with 1-5% v/v of the MBM. Ninety days later variables related to nematode reproduction and plant development were evaluated, which indicated a potential nematicidal effect of the MBM at 3%. Another experiment assessed nematode- and plant-related variables 90 days after treatment of the seedlings with MBM, chitosan, shrimp shell or neem cake at 3%, 0.05%, 2% and 0.1% v/v, respectively. The MBM ranked first, reducing nematode reproduction. This MBM rate was converted to 25 kg/tree and assessed in three application regimes (monthly, bimonthly or trimonthly, for six months, in an orchard affected by guava decline. The variables assessed were soil density of colony forming units (CFU of bacteria and fungus, and soil and/or root density of M. enterolobii, Helicotylenchus sp., and of different nematode trophic groups. In all three application regimes the MBM reduced all plant-parasitic nematodes in the soil and the fungus CFUs. It also promoted an increase in bacterial CFU and bacterivorous nematodes.

  16. Levantamento de Meloidogyne exigua na cultura da seringueira em São José do Rio Claro, MT, Brasil

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    Bernardo Eduardo Roberto de Almeida

    2003-01-01

    Full Text Available Este trabalho foi realizado com o objetivo de efetuar um levantamento da ocorrência de Meloidogyne exigua em seringueira em São José do Rio Claro, MT. Foram amostradas 191 propriedades agrícolas, totalizando cerca de 18.000ha. Os nematóides foram identificados no Laboratório de Nematologia do Departamento de Fitossanidade da FCAV/UNESP, em Jaboticabal, SP. Foram encontrados níveis populacionais de M. exigua entre 0 e 61.824 juvenis/5g de raízes.

  17. A multiplex real-time polymerase chain reaction (TaqMan) assay for the simultaneous detection of Meloidogyne chitwoodi and M-fallax

    NARCIS (Netherlands)

    Zijlstra, C.; Hoof, van R.A.

    2006-01-01

    This study describes a multiplex real-time polymerase chain reaction (PCR) approach for the simultaneous detection of Meloidogyne chitwoodi and M. fallax in a single assay. The approach uses three fluorogenic minor groove binding (MGB) TaqMan probes: one FAM-labeled to detect M. chitwoodi, one VIC-l

  18. Ocorrência de Meloidogyne enterolobii (sin. M. mayaguensis em pomares de goiabeira no município de Ivinhema, Estado de Mato Grosso do Sul

    Directory of Open Access Journals (Sweden)

    Héber Ferreira dos Reis

    2011-06-01

    Full Text Available Este trabalho relata uma ocorrência de Meloidogyne enterolobii (sin. M. mayaguensis no Estado do Mato Grosso do Sul, parasitando goiabeira (Psidium guajava, cv. Novo Milênio. O nematoide foi caracterizado e identificado pelo fenótipo da isoenzima esterase (Est (Est M2, Rm: 0,7 e 0,9.

  19. EFECTO DE POBLACIONES DE Meloidogyne sp. EN EL DESARROLLO Y RENDIMIENTO DEL TOMATE

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    Wilber Salazar-Ant\\u00F3n

    2013-01-01

    Full Text Available El objetivo de este trabajo fue determinar el efecto de la población inicial de Meloidogyne sp. en el cultivo del tomate. El estudio se realizó en León, Nicaragua en el año 2011. Las variables medidas fueron número de nematodos al trasplante y al momento de la cosecha, altura de la planta al momento de la madurez fisiológica y el rendimiento en kilogramos. La extracción de nematodos se realizó mediante el método de Baermann modificado. En el estudio, la densidad inicial (Pi presentó una correlación lineal positiva con la densidad final (Pf. Sin embargo, se observó que cuando la Pi era igual a 400 nematodos/100 g de suelo, el factor de reproducción se incrementaba a 3,64; por el contrario, cuando la Pi era igual a 700 nematodos/100 g de suelo, el factor de reproducción se reducía a 2,48. La Pi se correlacionó inversamente con el peso de frutos y altura de las plantas. Plantas con 200 nematodos/100 g de suelo presentaban peso de frutos de 2,19 kg y altura de 153,20 cm en comparación con 0,93 kg y 135,24 cm en plantas con 600 nematodos/100 g de suelo. Existió una correlación positiva entre Pi y Pf de Meloidogy- ne sp. en el tomate. Las poblaciones de este nematodo, se correlacionaron inversamente con las variables altura y peso de los frutos.

  20. EVALUATION OF THE REACTION OF WATERMELON PARENT AND F1 PLANTS TO Meloidogyne enterolobii

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    LÉIA SANTOS DAMACENO

    2016-01-01

    Full Text Available The aim of this study was to evaluate the performance of progenies from Citrullus lanatus var. lanatus (cultivated watermelons when crossed with progenies from C. lanatus var. citroides (fodder watermelon with a historic of resistance to the nematode Meloidogyne enterolobii. The parents and their F1s were evaluated for resistance to this nematode. In the initial stages of eleven treatments, watermelon seedlings plantlets were transplanted to plastic bags of six kilograms once the first leaves developed. Ten inoculated plants with 5,200 eggs in the soil near the stem of the plant and four non-inoculated ones were used in each treatment, in a complete block design. Sixty-two days after sowing, the following characteristics were evaluated: the length of the aerial part of the plant (LAP, in m, fresh mass of the aerial part (FMAP, in g, root fresh mass (RFM, in g, egg number (EN and reproduction factor (RF. A comparison between the averages of inoculated and non-inoculated plants was performed using Scott-Knott test at 5% and the diallelic analysis was performed using the GENES program. The morphological characteristics did not allow for the identification of the parent plants or the F1s with respect to nematode resistance, but the variables EN and RF were useful for such identification. The analyses of the general and specific combining abilities indicate highly significant effects with respect to this resistance, showing additive gene effects as well as dominance and epistatic gene effects, allowing for identification of parents and F1s that can be used in watermelon breeding programs to improve resistance to the M. enterolobii.

  1. Control of Meloidogyne javanica and M. arenaria on kenaf and roselle with genetic resistance and nematicides.

    Science.gov (United States)

    Minton, N A; Adamson, W C

    1979-01-01

    Kenaf (Hibiscus cannabinus) and roselle (H. sabdarifla) were evaluated in nematicide-treated and untreated field soil naturally infested with either Meloidogyne javanica or M. arenaria. Root-knot indices indicated that the kenaf breeding line j-l-113 had moderate resistance to M. javanica and low resistance to M. arenaria. Kenaf cv Everglades 71 was highly susceptible to both M. javanica and M. arenaria, and roselle breeding line A59-56 was highly resistant. Both nematode species reproduced on all plant entries, but more larvae were recovered from the soil in plots planted to Everglades 71 than in plots planted to j-l-l13 or A59-56. In untreated soil infested with M. javanica, dry-matter yields were greater (P = 0.05) for j-l-l13 and A59-56 than for Everglades 71. The percentages of live plants at harvest were: j-l-l13, 88; A59-56, 93; and Everglades 71, 9. Ethylene dibromide (1,2-dibromoethane) at 73.9 kg a.i./ha and DBCP (1,2-dibromo-3-chloropropane) at 17.6 kg a.i./ha increased dry-matter yields significantly for all entries planted in soil infested with M. arenaria. Carbofuran (2.3-dihydro-2,2-dimethyl-7-benzofuranyl methylcarbamate) at 5.9 kg a.i./ha did not increase the dry-matter yields of any entry. None of the nematicides increased the growth of any entry significantly in soil infested with M. javanica.

  2. Control of Meloidogyne chitwoodi in Potato with Shank-injected Metam Sodium and other Nematicides.

    Science.gov (United States)

    Ingham, R E; Hamm, P B; Baune, M; David, N L; Wade, N M

    2007-06-01

    Metam sodium (MS) is often applied to potato fields via sprinkler irrigation systems (water-run, WR) to reduce propagules of soil-borne pathogenic fungi, particularly Verticillium dahliae, to prevent yield loss from potato early dying disease. However, this procedure has not been effective for controlling quality defects in tubers caused by Columbia root-knot nematode (Meloidogyne chitwoodi). In five trials from 1996 to 2001, application of MS by soil shank injection (SH) provided better control and tuber quality than that generally obtained by WR MS, in three of five trials. Results were similar when SH MS was injected at one (41-45 cm), two (15 and 30 cm) or three (15, 30 and 45 cm) depths. In the two trials where SH metam potassium was tested, culls were reduced to 3% and 0% and were equivalent to those resulting from a similar rate in kg a.i./ha of SH MS. A shank-injected tank mix of MS plus ethoprop EC and SH MS plus in-season chemigation applications of oxamyl provided acceptable control in trials where SH MS alone was inadequate. In-furrow application of aldicarb at planting following SH MS did not appear to increase performance. Most consistent control (0-2% culled tubers in five trials) occurred when SH MS at 280 liters/ha was used together with 1,3- dichloropropene (140 liters/ha), applied simultaneously or sequentially. This was similar to combinations of 1,3-D and WR MS, but SH MS may be preferred under certain conditions.

  3. How to reduce the number of Meloidogyne paranaensis galls in tomato using earthworms?

    Directory of Open Access Journals (Sweden)

    Jair Alves Dionísio

    2014-02-01

    Full Text Available The objective of the present work was to determine the incidence of Meloidogyne paranaensis galls in the roots of Solanum lycopersicum, after inoculation with Amynthas spp. and Pontoscolex corethrurus. The experiment was performed in the greenhouse in a randomised block experimental design was adopted, with four treatments and five repetitions: T1. M. paranaensis; T2. M. paranaensis + Amynthas spp. T3. M. paranaensis +P. corethrurus; T4. M. paranaensis + Amynthas spp. + P. corethrurus. Initially, six adult worms of Amynthas spp. or P. corethrurus, isolated or in the same proportion (3:3, with the previously determined fresh biomass. After one week, tomato seedlings (cultivar “Rutgers” were transplanted to the pots and inoculated with 5 mL of a suspension of M. paranaensis containing 5,000 eggs and/or juveniles per pot. Sixty-five days after inoculation, the number of remaining worms was counted after manual collection; the fresh biomass was determined by direct weighing, and the number of galls on the roots of the tomato was counted directly in a stereomicroscope. The results demonstrated a reduction in the number of galls per plant with treatments involving inoculation with worms, varying between 26,7% and 63,3%, respectively, for Amynthas spp. and P. corethrurus. Meanwhile, the combination of worms lead to a reduction of 50,0% in the incidence of galls. The results demonstrate that the use of worms in the biological control of nematodes, during tomato cultivation, has great potential that requires further investigation.

  4. Respuesta de Zamia incognita L. al cultivo in vitro, una alternativa para su conservación

    Directory of Open Access Journals (Sweden)

    Aura I. Urrea

    2012-08-01

    Full Text Available Título en ingles: In vitro culture response on Zamia incognita,  an alternative for preservation Resumen: Las Zamiaceas son plantas relictuales consideradas fósiles vivientes. En Colombia, el 65% de esta familia se encuentra en alguna categoría de amenaza, por la destrucción del hábitat e intensa recolección. Teniendo en cuenta que entre las ventajas de la propagación in vitro está la conservación ex situ de germoplasma, el presente trabajo tuvo como objetivo evaluar el potencial de regeneración de plantas de Z. incognita a partir de explantes foliares y embriones cigoticos. Se evaluó el efecto de diferentes combinaciones de Auxinas (2,4-D y ANA y citoquininas (KIN, BAP y TDZ sobre la formación de callo  y la regeneración de brotes (directa o indirecta, utilizando como medio basal MS (MB1 y medio basal B5 modificado (MB2. La formación de callo se presentó sobre un amplio rango de concentraciones de 2,4-D con KIN y 2,4-D con BAP, independientemente del medio basal, pero no en los explantes tratados con ANA más KIN o TDZ.  Para los explantes foliares no hubo respuesta  a la formación de embriones somáticos y/o brotes con las combinaciones y concentraciones hormonales evaluadas, no obstante los callos inducidos en MB2 con 2,4-D (0,22 mg/l y BAP (0, 1, 2, 3 mg/l fueron diferentes, su aspecto nodular, color crema y  apariencia proembriogénica coincidió con una gran cantidad de células meristemáticas potenciales para el proceso de regeneración. A partir de embriones cigoticos inmaduros se logró la formación de embriones somáticos en el medio MB2 exento de reguladores o conteniendo 2,4-D solo (0,22 mg/l y en combinación con BAP (1 mg/l, sin lograr el proceso de conversión a plántulas. Palabras clave: micropropagación; hojas jóvenes; reguladores de crecimiento; embriones cigóticos; medio basal. Abstract: Zamiaceas are relict plants considered living fossils. In Colombia, 65% of this family is under some threat

  5. Hawksbill turtle terra incognita: conservation genetics of eastern Pacific rookeries.

    Science.gov (United States)

    Gaos, Alexander R; Lewison, Rebecca L; Liles, Michael J; Gadea, Velkiss; Altamirano, Eduardo; Henríquez, Ana V; Torres, Perla; Urteaga, José; Vallejo, Felipe; Baquero, Andres; LeMarie, Carolina; Muñoz, Juan Pablo; Chaves, Jaime A; Hart, Catherine E; Peña de Niz, Alejandro; Chácon, Didiher; Fonseca, Luis; Otterstrom, Sarah; Yañez, Ingrid L; LaCasella, Erin L; Frey, Amy; Jensen, Michael P; Dutton, Peter H

    2016-02-01

    Prior to 2008 and the discovery of several important hawksbill turtle (Eretmochelys imbricata) nesting colonies in the EP (Eastern Pacific), the species was considered virtually absent from the region. Research since that time has yielded new insights into EP hawksbills, salient among them being the use of mangrove estuaries for nesting. These recent revelations have raised interest in the genetic characterization of hawksbills in the EP, studies of which have remained lacking to date. Between 2008 and 2014, we collected tissue samples from 269 nesting hawksbills at nine rookeries across the EP and used mitochondrial DNA sequences (766 bp) to generate the first genetic characterization of rookeries in the region. Our results inform genetic diversity, population differentiation, and phylogeography of the species. Hawksbills in the EP demonstrate low genetic diversity: We identified a total of only seven haplotypes across the region, including five new and two previously identified nesting haplotypes (pooled frequencies of 58.4% and 41.6%, respectively), the former only evident in Central American rookeries. Despite low genetic diversity, we found strong stock structure between the four principal rookeries, suggesting the existence of multiple populations and warranting their recognition as distinct management units. Furthermore, haplotypes EiIP106 and EiIP108 are unique to hawksbills that nest in mangrove estuaries, a behavior found only in hawksbills along Pacific Central America. The detected genetic differentiation supports the existence of a novel mangrove estuary "reproductive ecotype" that may warrant additional conservation attention. From a phylogeographic perspective, our research indicates hawksbills colonized the EP via the Indo-Pacific, and do not represent relict populations isolated from the Atlantic by the rising of the Panama Isthmus. Low overall genetic diversity in the EP is likely the combined result of few rookeries, extremely small

  6. Phenotypic and molecular evaluation of cotton hairy roots as a model system for studying nematode resistance

    Science.gov (United States)

    The cellular mechanisms that mediate resistance of allotetraploid cotton (Gossypium spp.) to root-knot nematode (Meloidogyne incognita) and reniform nematode (Rotylenchulus reniformis) are poorly understood. Here, Agrobacterium rhizogenes-induced hairy roots were investigated as a possible research...

  7. EFEITOS DE PRODUTOS QUÍMICOS NO CONTROLE DE Meloidogyne sp SOBRE QUIABEIRO (Hibiscus sculentum L. EFFECTS OF CHEMICAL CONTROL OF Meloidogyne sp. IN Hibiscus sculentum L. IN OKRA

    Directory of Open Access Journals (Sweden)

    Lincoln Fonseca Zica

    2007-09-01

    Full Text Available

    Testou-se o poder nematicida de Shell-DD, Vapan, Nemagon granulado, brometo de metila e Neantina solúvel em solos com infestacão natural de Meloidogyne sp., usando-se o quiabeiro (Hibiscus escullentum L. como referência para medir a intensidade de infestação após o tratamento. O Shell-DD (40 ml/m² exerceu notável efeito nematicida, mas o Vapan (60 ml/m², o Nemagon granulado (40 g/m² e a Neantina solúvel (solução a 0,3% - 10 l/m² deram resultados estatisticamente iguais à testemunha. As parcelas tratadas com Brometo de metila (40 ml/m² foram perdidas em consequência do efeito fitotóxico do produto sobre as sementes e plântulas do quiabeiro.

    The nematicide power of Shell-DD, vapan, granulated nemagon, methyl bromide and soluble neantina, were tested by applying them to soil affected by Meloidogyne sp. The okra plant (Hibiscus esculentum L. was used as the hosting agent, to measure the amount of worms af-ter treatment. The results showed that Shell-DD (40 ml/m² controlled the worms well, but that vapan, granulated nemagon and the soluble neantina were statistically equal to the control plot. The plots treated with methyl bromide were not included in the results because of the toxic effect of the product on the plants.

  8. Dicty_cDB: SSM309 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available ary, BB17 Apis mellifera cDNA clone BB170024A20D04 5', mRNA sequence. 64 2e-12 3 AW570895 |AW570895.1 ra12e05.y1 Bird... 76 6e-10 1 AW588730 |AW588730.1 ra03h09.y2 Bird-Rao Meloidogyne incognita J2 Meloidogyne incognita cDNA 5'

  9. A New Root-Knot Nematode Parasitizing Sea Rocket from Spanish Mediterranean Coastal Dunes: Meloidogyne dunensis n. sp. (Nematoda: Meloidogynidae).

    Science.gov (United States)

    Palomares Rius, J E; Vovlas, N; Troccoli, A; Liébanas, G; Landa, B B; Castillo, P

    2007-06-01

    High infection rates of European sea rocket feeder roots by an unknown root-knot nematode were found in a coastal dune soil at Cullera (Valencia) in central eastern Spain. Morphometry, esterase and malate dehydrogenase electrophoretic phenotypes and phylogenetic trees demonstrated that this nematode species differs clearly from other previously described root-knot nematodes. Studies of host-parasite relationships showed a typical susceptible reaction in naturally infected European sea rocket plants and in artificially inoculated tomato (cv. Roma) and chickpea (cv. UC 27) plants. The species is herein described and illustrated and named as Meloidogyne dunensis n. sp. The new root-knot nematode can be distinguished from other Meloidogyne spp. by: (i) perineal pattern rounded-oval, formed of numerous fine dorsal and ventral cuticle striae and ridges, lateral fields clearly visible; (ii) female excretory pore at the level of stylet knobs, EP/ST ratio 1.6; (iii) second-stage juveniles with hemizonid located 1 to 2 annuli anteriorly to excretory pore and long, narrow, tapering tail; and (iv) males with lateral fields composed of four incisures anteriorly and posteriorly, while six distinct incisures are observed for large part at mid-body. Phylogenetic trees derived from distance and maximum parsimony analyses based on 18S, ITS1-5.8S-ITS2 and D2-D3 of 28S rDNA showed that M. dunensis n. sp. can be differentiated from all described root-knot nematode species, and it is clearly separated from other species with resemblance in morphology, such as M. duytsi, M. maritima, M. mayaguensis and M. minor.

  10. 不同药剂对南方根结线虫卵孵化及2龄幼虫活性的影响%Effect of Different Nematicides on Egg-hatching and 2nd Instar Larvae Mortality of Meloidogy incognita

    Institute of Scientific and Technical Information of China (English)

    漆永红; 曹素芳; 吕和平; 杜蕙

    2011-01-01

    Nematicidal effect of Abamectin, Fosthiazate, Abamectin ? Chlorpyrifos and Abamectin ? Carbosulfan on eggs-hatching in hibition in egg masses or in individual and the second instar larvae (J2) mortality of Meloidogyne incognita at different concentrations and times were tested in laboratory assay by dipping method. The results showed that all of nematicides had a strong inhibition ability to eggs hatching in egg masses or in individual and the mortality to J2. The eggs hatching inhibition and J2 mortality were significantly enhanced with the increase of treating concentration and times. 25 mg/L Fosthiazate demonstrated the highest inhibition effect on egg hatching in egg masses, the inhibition ratio was 10. 9% for 8 h and 100% after 16 h. And 10 mg/L Abamectin showed the highest inhibition effect on egg hatching in individual,with 80. 9% inhibition ratio treated for 8 h and 100% after 16 h. Meanwhile, Abamectin had distinctive activity against J2, its LC50 in 24 h to J2 in 24 h was 1. 970 1 mg/L,while Abamectin ? Chlorpyrifos did the weakest, the LC50 was 919. 878 1 mg/L.%在室内条件下,采用浸渍法测试质量分数为3%的阿维菌素EC、质量分数为10%的噻唑膦GR、质量分数为15%的灌根阿维·毒EC及质量分数为1.8%的阿维·丁硫克百威EC在不同质量浓度和时间处理下对南方根结线虫卵囊、卵孵化及2龄幼虫活性的影响.结果表明,供试药剂均对线虫卵、卵囊孵化起抑制作用,对2龄幼虫有致死作用.随着药剂质量浓度的增加和处理时间的延长,线虫卵、卵囊孵化的抑制率,2龄幼虫的死亡率显著提高.其中10%噻唑膦GR 25 mg/L对线虫卵囊孵化的抑制效果最好,处理8h抑制率达76.9%,16 h后达100%;3%阿维菌素EC 10 mg/L对线虫卵孵化有很强的抑制作用,处理8h达80.9%,16 h后达100%,同时不同药剂对2龄幼虫的活性测试结果表明,3%阿维菌素EC对南方根结线虫2龄幼虫的杀灭活性较强,其LC50

  11. Effect of Mulch Surface Color on Root-knot of Tomato Grown in Simulated Planting Beds

    OpenAIRE

    Fortnum, B. A.; Kasperbauer, M. J.; Decoteau, D. R.

    2000-01-01

    The effect of different-colored polyethylene mulches on quantity and spectra of reflected light, plant morphology, and root-knot disease was studied in tomato (Lycopersicon esculentum) grown in simulated planting beds. Tomato plants were inoculated with Meloidogyne incognita at initial populations (Pi) of 0, 1,000, 10,000, or 50,000 eggs/plant, and grown in a greenhouse for 50 days over white, red, or black mulch. Soil temperature was kept constant among the mulch treatments by placing an ins...

  12. Dicty_cDB: SSF460 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 0895 |AW570895.1 ra12e05.y1 Bird-Rao Meloidogyne incognita J2 Meloidogyne incogni...ry, BB17 Apis mellifera cDNA clone BB170024A20D04 5', mRNA sequence. 64 7e-10 2 AW588730 |AW588730.1 ra03h09.y2 Bird

  13. Dicty_cDB: VHF141 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available nce from clone RP11-560G8 on chromosome 9. 48 0.23 3 AW829533 |AW829533.1 ra41c11.y1 Bird-Rao Meloidogyne in...ce. 32 0.74 2 AW830038 |AW830038.1 ra48h04.y1 Bird-Rao Meloidogyne incognita J2 M

  14. Managing root-knot nematodes: A case for cover crops in establishing peach orchards

    Science.gov (United States)

    Root-knot nematodes (Meloidogyne spp.) are an important pathogen of peach in the United States. Several Meloidogyne spp. have been reported to cause damage to stone fruits, but M. incognita and M. javanica are the predominant species on peach. Preplant fumigant nematicides have traditionally been ...

  15. EFECTO NEMATICIDA DE EXTRACTOS DE Quassia amara Y Brugmansia suaveolens SOBRE Meloidogyne sp. ASOCIADO AL TOMATE EN NICARAGUA

    Directory of Open Access Journals (Sweden)

    Wilber Salazar-Ant\\u00F3n

    2014-01-01

    Full Text Available El objetivo de este trabajo fue evaluar extractos de hojas de Quassia amara L. (Simaroubaceae y flores de Brugmansia suaveolens L. (Solanaceae para determinar su efecto nematicida contra Meloidogyne sp. El estudio se realizó en el Campus Agropecuario de la Universidad Nacional Autónoma de Nicaragua-León (UNAN- León en el año 2012. El material vegetal fue deshidratado, pulverizado y sus compuestos fueron extraídos utilizando como solvente metanol. Este estudio se realizó in vitro, se evaluó la mortalidad de los juveniles de Meloidogyne sp. en segundo instar después de 12, 24 y 48 horas de exposición a los extractos. Además, estos se aplicaron a plantas de tomate en maceteras bajo condiciones de invernadero, cuantificándose las poblaciones de nematodos a los 25, 50 y 75 días de exposición al extracto (DEE. En el experimento in vitro Q. amara y B. suaveolens diluidos al 10%, presentaron los más altos porcentajes de mortalidad después de 48 h, alcanzando 89 y 78% de juveniles muertos, respectivamente. En maceteras se evaluó la mortalidad de juveniles, índice de agallamiento (IA y factor de reproducción (FR. Los mejores resultados para Q. amara se obtuvieron a los 25 DEE, con un porcentaje de mortalidad de 80%, un IA de 1 en una escala de 0-5 y FR de 0,20. Con B. suaveolens, a los 25 DEE se alcanzó el mayor porcentaje de mortalidad de 71%, un IA de 1,2 y un FR de 0,29. Estos resultados in vitro y en maceteras evidenciaron que ambos extractos poseen propiedades nematicidas, ya que redujeron significativamente (P≤0,05 las poblaciones de nematodos, su reproducción y el nivel de agallamiento de las raíces de tomate.

  16. OPDA has key role in regulating plant susceptibility to the root-knot nematode Meloidogyne hapla in Arabidopsis

    Directory of Open Access Journals (Sweden)

    Cynthia Gleason

    2016-10-01

    Full Text Available Jasmonic acid (JA is a plant hormone that plays important roles in regulating plant defenses against necrotrophic pathogens and herbivorous insects, but the role of JA in mediating the plant responses to root-knot nematodes has been unclear. Here we show that an application of either methyl jasmonate (MeJA or the JA-mimic coronatine (COR on Arabidopsis significantly reduced the number of galls caused by the root-knot nematode Meloidogyne hapla. Interestingly, the MeJA-induced resistance was independent of the JA-receptor COI1 (CORONATINE INSENSITIVE 1. The MeJA-treated plants accumulated the JA precursor cis-(+-12-oxo-phytodienoic acid (OPDA in addition to JA/JA-Isoleucine, indicating a positive feedback loop in JA biosynthesis. Using mutants in the JA-biosynthetic pathway, we found that plants deficient in the biosynthesis of JA and OPDA were hyper-susceptible to M. hapla. However, the opr3 mutant, which cannot convert OPDA to JA, exhibited wild-type levels of nematode galling. In addition, mutants in the JA-biosynthesis and perception which lie downstream of opr3 also displayed wild-type levels of galling. The data puts OPR3 (OPDA reductase 3 as the branch point between hyper-susceptibility and wild-type like levels of disease. Overall, the data suggests that the JA precursor, OPDA, plays a role in regulating plant defense against nematodes.

  17. Nematicidal activity of (E,E)-2,4-decadienal and (E)-2-decenal from Ailanthus altissima against Meloidogyne javanica.

    Science.gov (United States)

    Caboni, Pierluigi; Ntalli, Nikoletta G; Aissani, Nadhem; Cavoski, Ivana; Angioni, Alberto

    2012-02-01

    Methanol extracts of various plant parts of Ailanthus altissima were tested against the root knot nematode Meloidogyne javanica . Extracts of bark (ABE), wood (AWE), roots (ARE), and leaves (ALE) from A. altissima were investigated against freshly hatched second-stage juveniles (J(2)). AWE was the most active extract, with EC(50/3d) of 58.9 mg/L, while ALE, ARE, and ABE did not show nematicidal activity. The chemical composition of the extracts of A. altissima was determined by gas chromatography-mass spectrometry, and (E,E)-2,4-decadienal, (E)-2-undecenal, (E)-2-decenal, hexanal, nonanal, and furfural were the most prominent constituents. (E,E)-2,4-Decadienal, (E)-2-decenal, and furfural showed the highest nematicidal activity against M. javanica , with EC(50/1d) = 11.7, 20.43, and 21.79 mg/L, respectively, while the other compounds were inactive at the concentrations tested. The results obtained showed that AWE and its constituents (E,E)-2,4-decadienal and (E)-2-decenal could be considered as potent botanical nematicidal agents.

  18. Tomato progeny inherit resistance to the nematode Meloidogyne javanica linked to plant growth induced by the biocontrol fungus Trichoderma atroviride

    Science.gov (United States)

    Medeiros, Hugo Agripino de; Araújo Filho, Jerônimo Vieira de; Freitas, Leandro Grassi de; Castillo, Pablo; Rubio, María Belén; Hermosa, Rosa; Monte, Enrique

    2017-01-01

    Root-knot nematodes (RKN) are major crop pathogens worldwide. Trichoderma genus fungi are recognized biocontrol agents and a direct activity of Trichoderma atroviride (Ta) against the RKN Meloidogyne javanica (Mj), in terms of 42% reduction of number of galls (NG), 60% of number of egg masses and 90% of number of adult nematodes inside the roots, has been observed in tomato grown under greenhouse conditions. An in vivo split-root designed experiment served to demonstrate that Ta induces systemic resistance towards Mj, without the need for the organisms to be in direct contact, and significantly reduces NG (20%) and adult nematodes inside tomato roots (87%). The first generation (F1) of Ta-primed tomato plants inherited resistance to RKN; although, the induction of defenses occurred through different mechanisms, and in varying degrees, depending on the Ta-Mj interaction. Plant growth promotion induced by Ta was inherited without compromising the level of resistance to Mj, as the progeny of Ta-primed plants displayed increased size and resistance to Mj without fitness costs. Gene expression results from the defense inductions in the offspring of Ta-primed plants, suggested that an auxin-induced reactive oxygen species production promoted by Ta may act as a major defense strategy during plant growth. PMID:28071749

  19. Seleção de isolados de Paecilomyces lilacinus (Thom. Samson para controle de Meloidogyne paranaensis em tomateiro

    Directory of Open Access Journals (Sweden)

    Santiago Débora Cristina

    2006-01-01

    Full Text Available Paecilomyces lilacinus é uma espécie fúngica utilizada no controle biológico de nematóides, sendo uma das mais estudadas a campo. O trabalho teve como objetivo selecionar isolados de Paecilomyces lilacinus quanto à capacidade de controlar Meloidogyne paranaensis em tomateiro cv. "Santa Clara", em de casa-de-vegetação. Plantas cultivadas em vasos foram inoculadas com M. paranaensis. Após 45 dias da inoculação, efetuou-se a substituição dos tomateiros e foram aplicados 50 gramas de arroz autoclavado e colonizado por P. lilacinus. Decorridos 45 dias da inoculação do fungo, foram avaliados: número de galhas, massa de ovos, número de ovos por sistema radicular, peso da massa fresca da parte aérea, do sistema radicular e sobrevivência do P. lilacinus no solo. Todos os tratamentos com incorporação de P. lilacinus reduziram a população de M. paranaensis em raízes de tomateiro. Os isolados UEL pae 05, 08, 09, 13, 20, 21, 38, 41, 44, 54, ESALQ 831 e 832 foram os melhores no controle de M. paranaensis, afetando a reprodução dos nematóides e apresentando elevada sobrevivência no solo.

  20. Dicty_cDB: AFO620 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available alignments: (bits) Value N BM774584 |BM774584.1 ra95c11.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne ...B17 Apis mellifera cDNA clone BB170011A20F01 5', mRNA sequence. 64 2e-10 3 AW827814 |AW827814.1 ra59b10.y1 Bird...TASE ;, mRNA sequence. 48 4e-07 3 AW871572 |AW871572.1 ra79e06.y1 Bird-Rao Meloidogyne incognita J2 Meloidog

  1. Reação de clones de umezeiro (Prunus mume sieb. et zucc. e cultivares de pessegueiro a Meloidogyne javanica (treub, 1885 Chitwood, 1949

    Directory of Open Access Journals (Sweden)

    Mayer Newton Alex

    2003-01-01

    Full Text Available Um amplo projeto de estudos sobre a utilização do umezeiro como porta-enxerto para pessegueiro está sendo desenvolvido na FCAV/UNESP, Câmpus de Jaboticabal-SP, devido, especialmente, às promissoras características para uso como redutor de vigor da copa e sua boa qualidade de frutos. Alguns trabalhos na literatura citam o umezeiro como resistente ao nematóide das galhas, entretanto dispõe-se de poucas informações. Neste trabalho, teve-se por objetivo estudar a reação de clones de umezeiro e cultivares de pessegueiro a Meloidogyne javanica. O experimento foi conduzido em casa de vegetação, com 6 tratamentos (Clones 05; 10 e 15 de umezeiro e as cultivares Okinawa, Aurora-1 e Dourado-1 de pessegueiro e 9 repetições. As plantas foram mantidas em vasos de cerâmica contendo uma mistura de solo e areia (1:1, v/v, previamente autoclavada a 121ºC e 1kgf.cm-2 por 2 horas. Aos sessenta dias após o plantio, cada planta foi inoculada com 3.000 ovos e juvenis de segundo estádio de Meloidogyne javanica. Aos 100 dias após a inoculação, as plantas foram colhidas para avaliação da massa de matéria fresca do sistema radicular, número de galhas por sistema radicular, número de ovos e juvenis por 10 g de raízes, número de ovos e juvenis por sistema radicular e fator de reprodução. Verificou-se que todos os clones e cultivares de umezeiro e pessegueiro, respectivamente, mostraram-se resistentes a Meloidogyne javanica.

  2. Técnica molecular de PCR para identificar las principales especies de Meloidogyne spp. en poblaciones provenientes de Perú

    OpenAIRE

    Vera Obando, Nora Yessenia

    2014-01-01

    La correcta y confiable identificación de nematodos fitoparásitos del género Meloidogyne es importante para poder llevar a cabo estrategias de manejo integrado, mejoramiento y cuarentena. Por ello, se requiere la aplicación de técnicas complementarias y confirmatorias como la PCR (Reacción en cadena de la polimerasa), para apoyar la identificación de especies realizada por métodos morfológicos y morfométricos. En el presente trabajo se aisló 30 poblaciones a partir de una sola masa de huevos ...

  3. Multiplicação do nematoide Meloidogyne paranaensis e velocidade de enraizamento de estacas caulinares em sete espécies de plantas medicinais

    OpenAIRE

    Mendonça, Clarissa Izetti de

    2016-01-01

    Meloidogyne paranaensis foi caracterizado e descrito por Carneiro et al. como uma nova espécie em 1996. Os primeiros relatos demonstram a alta virulência que provocam em plantas de café no Estado do Paraná e São Paulo, destacando-se das demais espécies de nematoides pela sua agressividade e forte dano ao sistema radicular de cafeeiros. Recentemente, a espécie começou a ser pesquisada em plantas medicinais no Brasil. A primeira etapa, que teve por objetivo testar a reação de sete importantes e...

  4. Control of Meloidogyne enterolobii in guava seedlings with mycorrhizal fungi isolated from Bahia Savanna = Controle de Meloidogyne enterolobii em mudas de goiabeira com fungos micorrízicos isolados do Cerrado baiano.

    Directory of Open Access Journals (Sweden)

    Aracy Camilla Tardin Pinheiro

    2014-12-01

    Full Text Available The nematode Meloidogyne enterolobii causes severe damage to guava tree, being a limiting factor to production. Arbuscular mycorrhizal fungi (AMF can impair the development of some species of plant parasitic nematodes by reducing oviposition and the number of galls in the roots of infected plants. The present research aimed to evaluate the potential of AMF, isolated from soils of native savanna, in reducing the infectivity of M. enterolobii in guava tree seedlings. For this purpose, an experiment was conducted in a greenhouse in randomized block design with eight replications, in which we evaluated the percentage of mycorrhizal colonization, the number of galls and eggs of the mentioned nematode per gram of root, in the presence of eight different fungal isolates, and the control without the presence of the fungus, in the guava tree. All AMF isolates from the savanna were effective on root colonization, reduced the number of nematode’s galls and affected their reproduction; however, the degree of root colonization by mycorrhizal fungi, alone, is not indicative of infectivity control of this pathogen, since some isolates showing increased colonization were less effective in reducing it, so that the evaluated AMF isolates differed regarding the efficiency in reducing the reproduction of M. enterolobii in guava tree seedlings. = O nematoide Meloidogyne enterolobii causa severos danos à goiabeira, sendo um fator limitante à produção. Os fungos micorrízicos arbusculares (FMA podem prejudicar o desenvolvimento de algumas espécies de nematoides fitoparasitos, reduzindo a ovoposição e o número de galhas no sistema radicular de plantas infectadas. Com o presente trabalho, objetivouse avaliar o potencial de FMA, isolados de solos de cerrado nativo, em reduzir a infectividade de M. enterolobii em mudas de goiabeira. Para tanto, foi conduzido um experimento em casa de vegetação, em blocos casualizados com oito repetições, no qual se avaliou a

  5. SELEÇÃO DE GENÓTIPOS DE ABACAXI PARA RESISTÊNCIA A Meloidogyne javanica E Pratylenchus brachyurus RESISTANCE OF PINEAPPLE GENOTYPES TO Meloidogyne javanica AND Pratylenchus brachyurus

    Directory of Open Access Journals (Sweden)

    Carlos Humberto Calfa

    2007-09-01

    Full Text Available

    Dez genótipos de abacaxi foram avaliados para resistência às espécies de nematóides, Meloidogyne javanica e Pratylenchus brachyurus, em dois experimentos conduzidos em casa de vegetação, seguindo o delineamento inteiramente casualizado com seis repetições, empregando o cv. Smooth Cayenne como padrão de suscetibilidade. Cada parcela foi constituída de uma planta/vaso, contendo solo esterilizado com brometo de metila. Após dois meses do plantio das mudas, as plantas foram inoculadas com 1.000 juvenis (J2 de M. javanica no primeiro experimento e 1.000 indivíduos de P. brachyurus no segundo experimento. Após 90 dias da inoculação foram avaliados os seguintes parâmetros: peso do sistema radicular, número de ovos e de nematóides por planta e fatores de reprodução. A seleção para resistência foi baseada na percentagem de redução do fator de reprodução. Em relação a M. javanica, os genótipos FRF-632 e H-3607 foram pouco resistentes (PR e os de LBB-1385, Primavera, FRF-609 e LBB-1396 comportaram-se como moderadamente resistentes (MR. Para P. brachyurus foram selecionados como pouco resistentes (PR os genótipos de H-3607, LBB-396, Perolera, FRF-609 e Primavera.

    PALAVRAS-CHAVES: Ananas comosus; resistência; nematóide das galhas; nematóide das lesões radiculares.

    The resistance of ten genotypes of pineapple to two nematodes species, Meloidogyne javanica and Pratylenchus brachyurus, was evaluated in two experiments at greenhouse. Each one of them was completely randomized with six replications. The cultivar Smooth Cayenne was used as a susceptible control. Each plot was represented by one plant/pot. Each pot held 4 l of soil

  6. Identificação de linhagens avançadas de alface quanto à resistência a Meloidogyne javanica Identification of advanced lineages of lettuce resistant to Meloidogyne javanica

    Directory of Open Access Journals (Sweden)

    Sindynara Ferreira

    2011-04-01

    Full Text Available Objetivou-se, no presente trabalho, avaliar o comportamento de linhagens de alface quanto à resistência ao nematoide das galhas Meloidogyne javanica, identificando a provável existência de linhagens homozigotas para o caráter. Foram utilizados como tratamentos cinco linhagens F4 e seis linhagens F5, juntamente com as testemunhas 'Grand Rapids' (resistente e 'Regina 71' (suscetível, além da cultivar de tomateiro Santa Clara. A semeadura foi feita em bandejas de poliestireno expandido, sendo o substrato infestado com ovos de M. javanica, na proporção de 30 ovos cm-3 de substrato. Aos quarenta e sete dias após a infestação, cada planta foi avaliada individualmente quanto aos seguintes caracteres: índice visual de galhas, número de ovos, fator de reprodução e índice de reprodução. Cada linhagem foi comparada com as testemunhas 'Regina 71' e 'Grand Rapids', para cada característica, através do teste de Dunnett (5%, obtendo-se a significância em relação a cada uma das testemunhas, permitindo a classificação de cada linhagem como homozigota resistente, homozigota suscetível ou segregante. Pelos resultados obtidos conclui-se que seis linhagens (AFX 018C 002 23 15, AFX 018C 002 23 22, AFX 018C 005 42 20, AFX 018C 005 44 22, AFX 018C 005 44 28 e AFX 022B 010 31 foram consideradas homozigotas resistentes para as características avaliadas, podendo ser utilizadas como novas fontes de resistência ao M. javanica em programas de melhoramento de alface.The objective of the present work was to evaluate the behavior of lettuce lineages as for resistence to nematode from the Meloidogyne javanica root-knots, identifying probable existence of homozigote lineages for the characteristics. Five F4 and six F5 lineages were used as treatments together with the controls 'Grand Rapids' (resistent and 'Regina 71' (susceptible, apart from the Santa Clara tomato plant cultivar. The sowing was done over expanded polystyrene trays with the substrate

  7. Crescimento micelial e parasitismo de Paecilomyces lilacinus sobre ovos de Meloidogyne paranaensis em diferentes temperaturas"in vitro" "In vitro" mycelial growth and parasitism of Paecilomyces lilacinus on Meloidogyne paranaensis eggs at different temperatures

    Directory of Open Access Journals (Sweden)

    Marina Capparelli Cadioli

    2007-04-01

    Full Text Available Paecilomyces lilacinus é um fungo de solo, parasita facultativo de ovos de nematóides, que pode crescer rapidamente "in vitro". Este trabalho teve como objetivo avaliar o crescimento micelial de P. lilacinus em diferentes temperaturas e selecionar os melhores isolados quanto à capacidade de parasitar ovos de Meloidogyne paranaensis. Foram avaliados isolados de P. lilacinus, obtidos de solos coletados na região de Londrina, PR. Para o isolamento empregou-se a técnica de diluição seriada dos solos e plaqueamento em meio de cultura semi-seletivo. A determinação do crescimento micelial e do parasitismo "in vitro" dos isolados sobre M. paranaensis foi realizada em placas de Petri contendo meio BDA. Os isolados foram incubados em B.O.D. a temperaturas de 20ºC, 22,5ºC, 25ºC, 27,5ºC e 30ºC. A avaliação do crescimento foi interrompida quando em um dos tratamentos a colônia do fungo atingiu a borda da placa de Petri e a determinação do parasitismo foi realizada depois de oito dias de incubação, calculando-se a porcentagem de ovos parasitados. O crescimento micelial dos isolados de P. lilacinus teve grande dependência da temperatura de incubação a que foram submetidos, sendo mais rápido à temperatura de 22,5ºC. Os isolados de P. lilacinus revelaram habilidade para infectar os ovos de M. paranaensis em meio BDA, principalmente na temperatura de 25ºC.Paecilomyces lilacinus is a soil fungus, facultative parasite of nematode eggs, which develops quickly "in vitro". The mycelial growth of P. lilacinus isolates was evaluated at different temperatures and the best isolates, regarding the capacity to parasite Meloidogyne paranaensis eggs, were chosen. P. lilacinus soil isolates from Londrina, Parana state, were evaluated. Isolation was done using serial dilution of the soils and plating it in semi-selective agar medium. The determination of mycelial growth and "in vitro" parasitism of these isolates was done using Petri plates

  8. Root-Lesion Nematodes Suppress Cabbage Aphid Population Development by Reducing Aphid Daily Reproduction.

    Science.gov (United States)

    Hol, W H G; Raaijmakers, Ciska E; Mons, Ilse; Meyer, Katrin M; van Dam, Nicole M

    2016-01-01

    Empirical studies have shown that belowground feeding herbivores can affect the performance of aboveground herbivores in different ways. Often the critical life-history parameters underlying the observed performance effects remain unexplored. In order to better understand the cause for the observed effects on aboveground herbivores, these ecological mechanisms must be better understood. In this study we combined empirical experiments with a modeling approach to analyze the effect of two root feeding endoparasitic nematodes with different feeding strategies on the population growth of the aboveground feeding specialist aphid Brevicoryne brassicae on Brassica nigra. The aim was to test whether emerging differences in life history characteristics (days until reproduction, daily reproduction) would be sufficient to explain observed differences in aphid population development on plants with and without two species of nematodes. Aphid numbers were lower on plants with Pratylenchus penetrans in comparison to aphid numbers on plants with Meloidogyne spp. A dedicated experiment showed that aphid daily reproduction was lower on plants with P. penetrans (3.08 offspring female(-1) day(-1)) in comparison to both uninfested plants and plants with Meloidogyne spp. (3.50 offspring female(-1) day(-1)). The species-specific reduction of aphid reproduction appeared independent of changes in amino acids, soluble sugars or the glucosinolate sinigrin in the phloem. An individual-based model revealed that relatively small differences in reproduction rate per female were sufficient to yield a similar difference in aphid populations as was found in the empirical experiments.

  9. Plant-mediated RNA interference of effector gene Mc16D10L confers resistance against Meloidogyne chitwoodi in diverse genetic backgrounds of potato and reduces pathogenicity of nematode offspring

    Science.gov (United States)

    Meloidogyne chitwoodi is a major problem for potato production in the Pacific Northwest of the USA. In spite of long-term breeding efforts no commercial potato cultivars with resistance to M. chitwoodi exist to date. The RMc1 resistance gene against M. chitwoodi has been introgressed from Solanum bu...

  10. Comparison of two short DNA barcoding loci (COI and COII) and two longer ribosomal DNA genes (SSU & LSU rRNA) for specimen identification among quarantine root-knot nematodes (Meloidogyne spp.) and their close relatives

    NARCIS (Netherlands)

    Kiewnick, S.; Holterman, M.H.M.; Elsen, van den S.J.J.; Megen, van H.H.B.; Frey, J.E.; Helder, J.

    2014-01-01

    Root-knot nematodes (Meloidogyne spp.) are important pests of numerous crops worldwide. Some members of this genus have a quarantine status, and accurate species identification is required to prevent further spreading. DNA barcoding is a method for organism identification in non-complex DNA backgrou

  11. Dual RNA-seq reveals Meloidogyne graminicola transcriptome and candidate effectors during the interaction with rice plants.

    Science.gov (United States)

    Petitot, Anne-Sophie; Dereeper, Alexis; Agbessi, Mawusse; Da Silva, Corinne; Guy, Julie; Ardisson, Morgane; Fernandez, Diana

    2016-08-01

    Root-knot nematodes secrete proteinaceous effectors into plant tissues to facilitate infection by suppressing host defences and reprogramming the host metabolism to their benefit. Meloidogyne graminicola is a major pest of rice (Oryza sativa) in Asia and Latin America, causing important crop losses. The goal of this study was to identify M. graminicola pathogenicity genes expressed during the plant-nematode interaction. Using the dual RNA-sequencing (RNA-seq) strategy, we generated transcriptomic data of M. graminicola samples covering the pre-parasitic J2 stage and five parasitic stages in rice plants, from the parasitic J2 to the adult female. In the absence of a reference genome, a de novo M. graminicola transcriptome of 66 396 contigs was obtained from those reads that were not mapped on the rice genome. Gene expression profiling across the M. graminicola life cycle revealed key genes involved in nematode development and provided insights into the genes putatively associated with parasitism. The development of a 'secreted protein prediction' pipeline revealed a typical set of proteins secreted by nematodes, as well as a large number of cysteine-rich proteins and putative nuclear proteins. Combined with expression data, this pipeline enabled the identification of 15 putative effector genes, including two homologues of well-characterized effectors from cyst nematodes (CLE-like and VAP1) and a metallothionein. The localization of gene expression was assessed by in situ hybridization for a subset of candidates. All of these data represent important molecular resources for the elucidation of M. graminicola biology and for the selection of potential targets for the development of novel control strategies for this nematode species.

  12. CONTROLE ALTERNATIVO DE NEMATOIDE DAS GALHAS (Meloidogyne enterolobii COM CRAVO DE DEFUNTO (Tagetes patula L., EM SOLO

    Directory of Open Access Journals (Sweden)

    Francisco José Carvalho Moreira

    2015-03-01

    Full Text Available A correta identificação de fitopatógenos é de grande importância para se formar um acervo de dados que serão úteis para diagnose e controle. Com o aumento do plantio de goiaba no Ceará, percebe-se a presença de Meloidogyne associado à cultura e causando grandes prejuízos, contudo, o controle para tal moléstia ainda não existe. Em função disso, objetivou-se nesse ensaio avaliar o controle alternativo de M. enterolobii com a incorporação de fitomassa de cravo de defunto. O trabalho foi realizado de janeiro a maio de 2009, em Barbalha-CE. A avaliação do efeito da incorporação da fitomassa de cravo de defunto ao solo foi realizada em função da idade de transplantio (12, 18, 24 e 30 dias. Avaliou-se aos 35 dias após o transplantio do tomate, sendo mensuradas: número de galhas, peso fresco da parte aérea e do sistema radicular. Verificou-se que a incorporação da fitomassa de cravo de defunto ao solo apresentou-se eficiente na redução da população do nematoide. Conclui-se que a incorporação de fitomassa é eficiente na redução populacional de M. enterolobii e que 30 dias após o transplantio é a melhor época para se cortar e incorporá-la ao solo.

  13. Effect of Meloidogyne arenaria and Mulch Type on Okra in Microplot Experiments.

    Science.gov (United States)

    Ritzinger, C H; McSorley, R; Gallaher, R N

    1998-12-01

    The effects of perennial peanut (Arachis glabrata) hay, an aged yard-waste compost (mainly woodchips), and a control treatment without amendment were determined on two population levels of root-knot (Melaidogyne arenaria) nematode over three consecutive years in field microplots. Okra (Hibiscus esculentus, susceptible to the root-knot nematode) and a rye (Secale cereale) cover crop (poor nematode host) were used in the summer and winter seasons, respectively. The organic amendment treatments affected plant growth parameters. In the first year, okra yields were greatest in peanut-amended plots. Yield differences with amendment treatment diminished in the second and third years. Okra plant height, total fruit weight, and fruit number were greater with the lower population level of the root-knot nematode. Residual levels of nutrients in soil were greater where root-knot nematode levels and damage were higher and plant growth was poor. Nutrient levels affected the growth of a subsequent rye cover crop.

  14. Controle de Meloidogyne javanica em mudas de bananeira 'prata-anã' por compostos orgânicos

    Directory of Open Access Journals (Sweden)

    Bruna Hanielle Carneiro dos Santos

    2013-06-01

    Full Text Available O trabalho teve como objetivo avaliar o efeito de compostos orgânicos no controle de Meloidogyne javanica, e no desenvolvimento de mudas de bananeiras 'Prata-Anã. O experimento foi conduzido em DIC, com dez repetições, e os tratamentos consistiram em quatro compostos constituídos de diferentes matérias-primas (restos da cultura da banana, cana-de-açúcar, esterco bovino, cascas de banana, plantas daninhas, capim andropogon, o esterco bovino, a torta de mamona e testemunhas (adubação mineral, carbofuran e testemunha absoluta (sem adição de composto orgânico. Em cada vaso, foram colocados 3 kg de solo autoclavado, incorporado com cada um dos tratamentos avaliados e inoculado com suspensão contendo 4.000 ovos de M. javanica. Após quatro dias, transplantou-se uma muda de bananeira 'Prata-Anã' micropropagada, e aos 60 dias, avaliaram-se: altura das plantas, diâmetro, número de folhas e peso de matéria seca da parte aérea, e número de galhas, massas de ovos, número de ovos e o número de juvenis de segundo estádio (J2, por 100 cm³ de solo. Testou-se in vitro o efeito das frações húmicas dos quatro compostos (que não causaram fitotoxidez e esterco bovino sobre a mortalidade e motilidade de J2 de M. javanica. O ensaio foi montado em placas de ELISA em DIC, com cinco repetições. Os compostos orgânicos e o esterco bovino aumentaram o desenvolvimento das mudas. A torta de mamona provocou efeito fitotóxico às mudas. Menor número de variáveis nematológicas foi proporcionado pela torta de mamona e pelo carbofuran. O número de J2 também foi menor nas parcelas tratadas com carbofuran e também pelo Composto 3, constituído por plantas daninhas+restos de cana-de-açúcar+ esterco bovino e pelo adubo mineral. Para o teste in vitro, as substâncias húmicas conferiram efeito nematicida e nematostático. Dentre os compostos, o C3 mostrou-se promissor por reduzir o desenvolvimento do nematoides e não apresentar efeito fitotóxico.

  15. Bioactive Volatiles from an Endophytic Daldinia cf. concentrica Isolate Affect the Viability of the Plant Parasitic Nematode Meloidogyne javanica

    Science.gov (United States)

    Braun Miyara, Sigal; Ezra, David

    2016-01-01

    Plant-parasitic nematodes form one of the largest sources of biotic stress imposed on plants, and are very difficult to control; among them are the obligate parasites, the sedentary root-knot nematodes (RKNs)–Meloidogyne spp.–which are extremely polyphagous and exploit a very wide range of hosts. Endophytic fungi are organisms that spend most of their life cycle within plant tissue without causing visible damage to the host plant. Many endophytes secrete specialized metabolites and/or emit volatile organic compounds (VOCs) that exhibit biological activity. Recently, we demonstrated that the endophytic fungus Daldinia cf. concentrica secrets biologically active VOCs. Here we examined the ability of the fungus and its VOCs to control the RKN M. javanica both in vitro and greenhouse experiments. The D. cf. concentrica VOCs showed bionematicidal activity against the second-stage juveniles (J2s) of M. javanica. We found that exposure of J2s to fungal volatiles caused 67% reduction in viability, and that application of a synthetic volatile mixture (SVM), comprising 3-methyl-1-butanol, (±)-2-methyl-1-butanol, 4-heptanone, and isoamyl acetate, in volumetric ratio of 1:1:2:1 further reduced J2s viability by 99%. We demonstrated that, although each of the four VOCs significantly reduced the viability of J2s relative to the control, only 4-heptanone elicited the same effect as the whole mixture, with nematicidal activity of 90% reduction in viability of the J2s. Study of the effect of the SVM on egg hatching demonstrated that it decreased eggs hatching by 87%. Finally, application of the SVM to soil inoculated with M. javanica eggs or J2s prior to planting susceptible tomato plants resulted in a significantly reduced galling index and fewer eggs produced on each root system, with no effect on root weight. Thus, D. cf. concentrica and/or SVM based on fungal VOCs may be considered as a novel alternative approach to controlling the RKN M. javanica. PMID:27997626

  16. Suppression of Meloidogyne javanica by antagonistic and plant growth-promoting rhizobacteria

    Institute of Scientific and Technical Information of China (English)

    LI Bin; XIE Guan-lin; SOAD A.; COOSEMANS J.

    2005-01-01

    Four rhizobacteria selected out of over 500 isolates from rhizosphere of the vegetables in China were further studied for suppression of the root-knot nematode and soil-borne fungal pathogens in laboratory and greenhouse in Belgium. They were identified as Brevibacillus brevis or Bacillus subtilis by Biolog test and partial 16s rDNA sequence comparison. They not only inhibited the radial growth of the root-infecting fungi Rhizoctonia solani SX-6, Pythium aphanidermatum ZJP-1 and Fusarium oxysporum f. sp. cucumerinum ZJF-2 in vitro, but also exhibited strong nematicidal activity by killing the second stage larvae of Meloidogynejavanica to varying degrees in the greenhouse. The toxic principles of bacterium B7 that showed the highest juvenile mortality were partially characterized. The active factors were heat stability and resistance to extreme pH values. B7 used either as seed dressing or soil drench significantly reduced the nematode populations in the rhizosphere and enhanced the growth of mungbean plants over the controls in the presence or absence ofR. solani.

  17. Effects and carry-over benefits of nematicides in soil planted to a sweet corn-squash-vetch cropping system.

    Science.gov (United States)

    Johnson, A W; Leonard, R A

    1995-12-01

    The effects of irrigation on the efficacy of nematicides on Meloidogyne incognita race 1 population densities, yield of sweet corn, and the carry-over of nematicidal effect in the squash crop were determined in a sweet corn-squash-vetch cropping system for 3 years. Fenamiphos 15G and aldicarb 15G were applied at 6.7 kg a.i./ha and incorporated 15 cm deep with a tractor-mounted rototiller. Ethylene dibromide (EDB) was injected at 18 kg a.i./ha on each side of the sweet corn rows (total 36 kg a.i./ha) at planting for nematode control. Supplemental sprinkler irrigation (1.52-4.45 cm), applied in addition to natural rainfall (4.60-10.80 cm) within l0 days after application of nematicides, did not affect nematicide efficacy against M. incognita or yield of sweet corn. Soil treatment with fenamiphos, EDB, and aldicarb increased the number and total weight of sweet corn ears and the weight per ear each year over untreated controls (P nematicides provided some control of M. incognita on squash planted after sweet corn, but yields were consistently greater and root-gall indices lower on squash following sweet corn treated with fenamiphos than other nematicides.

  18. Innate gamma/delta T-cells during HIV infection: Terra relatively Incognita in novel vaccination strategies?

    Science.gov (United States)

    Agrati, Chiara; D'Offizi, Gianpiero; Gougeon, Marie-Lise; Malkovsky, Miroslav; Sacchi, Alessandra; Casetti, Rita; Bordoni, Veronica; Cimini, Eleonora; Martini, Federico

    2011-01-01

    HIV replication. Scarce evidences are available on the involvement of mucosal gamma/delta T-cells during the early phases of HIV infection. In particular, the relative cause/effect links between HIV infection, destruction of the mucosal physical barrier, nonspecific activation of the immune system, and mucosal innate cell activation and effector functions, are still not completely defined. In order to attain an effective manipulation of innate immune cells, aiming at the induction of an effective adaptive immunity against HIV, any information on the role of mucosal antiviral factors and innate immune cells will be very important. The aim of this review is to summarize the information on the role of gamma/delta T-cells during HIV infection, from the general circulating population to mucosal sites, in order to better describe areas deserving increased attention. In particular, strategies enhancing gamma/delta T-cell functions may open the possibility to formulate new immunotherapeutic regimens, which could impact the improvement of immune control of HIV disease.

  19. Species of Root-knot Nematodes and Fungal Egg Parasites Recovered from Vegetables in Almería and Barcelona, Spain

    OpenAIRE

    Verdejo Lucas, Soledad; Ornat Longarón, Cèsar; Sorribas Royo, Francisco Javier; Stchigel, Alberto Miguel

    2002-01-01

    Intensive vegetable production areas were surveyed in the provinces of Almería (35 sites) and Barcelona (22 sites), Spain, to determine the incidence and identity of Meloidogyne spp. and of fungal parasites of nematode eggs. Two species of Meloidogyne were found in Almería—M. javanica (63% of the samples) and M. incognita (31%). Three species were found in Barcelona, including M. incognita (50%), M. javanica (36%), and M. arenaria (14%). Solanaceous crops supported larger (P < 0.05) nematode ...

  20. Dicty_cDB: SSM729 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 625.2 Drosophila melanogaster chromosome 2L section 34 of 83 of the complete sequence. 44 1.6 1 AW571255 |AW571255.1 ra16b04.y2 Bird...nogaster, *** SEQUENCING IN PROGRESS ***, in ordered pieces. 44 1.6 1 AW570934 |AW570934.1 ra13a02.y1 Bird-R...a09.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incognita cDNA 5', mRNA s

  1. Ação nematicida de extratos de alho, mostarda, pimenta malagueta, de óleo de mostarda e de dois produtos à base de capsainóides e alil isotiocianato sobre juvenis de Meloidogyne javanica, (treub Chitwood, 1949, em casa de vegetação

    Directory of Open Access Journals (Sweden)

    Wânia dos Santos Neves

    2009-12-01

    o extrato clorofórmico de pimenta, o óleo de mostarda, o produto comercial Champon® e um produto em desenvolvimento na UFV, chamado DS, a base de capsaicina, capsainóides e alil isotiocianato em diferentes concentrações. Os produtos Champon® e DS e o óleo de mostarda reduziram o número de ovos e galhas quando comparados à testemunha em todas as concentrações testadas. O extrato de pimenta apresentou o melhor resultado na concentração de 400 ppm, reduzindo o número de ovos e galhas em relação à testemunha, porém esse foi bem maior quando comparado com os demais produtos testados.Neves, W.S; Freitas, L.G.; Coutinho, M.M.; Giaretta-Dallemole, R.; Fabry, C.F.S.; Dhingra, O.D. & Ferraz, S. Nematicidal activity of extracts of red hot chili pepper, mustard and garlic on Meloidogyne javanica in green house. Summa Phytopathologica, v.35, n.4, p.255-261, 2009 The experiment had the objectives of evaluate the nematicidal activity of botanical extracts of chili pepper fruits (Capsicum frutescens, mustard (Brassica campestris and garlig (Allium sativum on the root-knot nematode, Meloidogyne javanica in tomato plants in the greenhouse, and in a second step, to compare the best extracts for the reduction of the number of eggs and root galls with two products containing capsaicin, capsainoids and allyl isothiocyanate. A sieved mixture of soil and sand 1:1 (v:v was used to fill plastic pots and infested with 4000 eggs of M. javanica. After 4 days, 20 mL of one of the extracts, in the concentration of 1000ppm, were poured over the soil of each pot. Water was poured in the test treatment. Twenty day-old tomato seedlings were planted, one per pot, four days after the aplication of the extracts. Forty five days after planting, the number of galls and eggs per plant was evaluated. The chloroformic and cetonic extracts of chili pepper and the mustard oil presented the highest effect on the nematode population, differing from the control treatment in respect to the

  2. Species-dependent effects of border cell and root tip exudates on nematode behavior.

    Science.gov (United States)

    Zhao, X; Schmitt, M; Hawes, M C

    2000-11-01

    ABSTRACT Effects of border cell and root tip exudates on root knot nematode (Meloidogyne incognita) behavior were examined. In whole-plant assays using pea, M. incognita second-stage juveniles (J2) accumulated rapidly around the 1- to 2-mm apical region ensheathed by border cells, but not in the region of elongation. Within 15 to 30 min, J2 which had accumulated within detached clumps of border cells lost motility and entered into a quiescent state. When border cells (and associated root tip exudates) were washed from pea roots prior to challenge with nematodes, no such accumulation and quiescence was induced. Attraction of nematodes by roots was species dependent: no attraction or accumulation occurred in snap bean. Using a quantitative assay, three categories of chemotaxis responses occurred: attraction (pea and alfalfa cv. Thor), repulsion (alfalfa cv. Moapa 69), and no response (snap bean and alfalfa cv. Lahonton). In contrast, total root tip exudates from all three plant species acted as a repellent for M. incognita in the sand assay. An in vitro assay was developed to characterize the induced quiescence response. When total root tip exudate from the tested legumes (as well as corn) was incubated with J2 populations, >80% of the nematodes lost motility. A similar response occurred in Caenorhabditis elegans. Border cell exudates did not induce or contribute to the induction of quiescence. Cocultivation of pea border cells with M. incognita resulted in changes in border cell shape similar to those observed in response to exogenous plant hormones. No such changes occurred in snap bean border cells. Understanding the cell- and host-specific extracellular recognition that occurs between roots and pathogenic nematodes in the early stages before infection occurs could lead to new avenues for disease control.

  3. Preliminary study of the green algae chlorella (Chlorella vulgaris) for control on the root-knot nematode (Meloidogyne arenaria) in tomato plants and ectoparasite Xiphinema indexin grape seedlings.

    Science.gov (United States)

    Choleva, B; Bileva, T; Tzvetkov, Y; Barakov, P

    2005-01-01

    The alternative ecological methods require investigation of many organo-biological means for plant protection against dangerous root parasites such as root-knot nematode Meloidogyne arenaria and some ectoparasites (Xiphinema index). The Bulgarian organic product - dry extract of green alga Chlorella vulgaris ("The Golden Apple"-Plamen Barakov) is the latest product, which in comparative aspect gives the best results. Series of laboratory and pot experiments are carried out with tomato (cv. Bele and cv. Ideal) and grape seedlings (cv. Cabernet Sauvignon). Different dosages of Chlorella from 0.5 g to 2 g per plant/pot are investigated. The first results show that even low dosages had double effect - on the one hand they suppress the parasite development and on the other hand they strongly stimulate plant growing. The very important conclusion is that Chlorella vulgaris ignores the negative influence of M. arenaria and X. index. These results give us opportunity for future model and field investigations of Chlorella vulgaris with the aim of its practical application.

  4. In vitro uptake of 140 kDa Bacillus thuringiensis nematicidal crystal proteins by the second stage juvenile of Meloidogyne hapla.

    Directory of Open Access Journals (Sweden)

    Fengjuan Zhang

    Full Text Available Plant-parasitic nematodes (PPNs are piercing/sucking pests, which cause severe damage to crops worldwide, and are difficult to control. The cyst and root-knot nematodes (RKN are sedentary endoparasites that develop specialized multinucleate feeding structures from the plant cells called syncytia or giant cells respectively. Within these structures the nematodes produce feeding tubes, which act as molecular sieves with exclusion limits. For example, Heterodera schachtii is reportedly unable to ingest proteins larger than 28 kDa. However, it is unknown yet what is the molecular exclusion limit of the Meloidogyne hapla. Several types of Bacillus thuringiensis crystal proteins showed toxicity to M. hapla. To monitor the entry pathway of crystal proteins into M. hapla, second-stage juveniles (J2 were treated with NHS-rhodamine labeled nematicidal crystal proteins (Cry55Aa, Cry6Aa, and Cry5Ba. Confocal microscopic observation showed that these crystal proteins were initially detected in the stylet and esophageal lumen, and subsequently in the gut. Western blot analysis revealed that these crystal proteins were modified to different molecular sizes after being ingested. The uptake efficiency of the crystal proteins by the M. hapla J2 decreased with increasing of protein molecular mass, based on enzyme-linked immunosorbent assay analysis. Our discovery revealed 140 kDa nematicidal crystal proteins entered M. hapla J2 via the stylet, and it has important implications in designing a transgenic resistance approach to control RKN.

  5. Nematofauna associada à cultura do quiabo na região leste de Minas Gerais The influence of parasitic nematodes on okra crop in eastern Minas Gerais State, Brazil

    Directory of Open Access Journals (Sweden)

    Rosângela D'Arc de Lima Oliveira

    2007-03-01

    of these nematodes attacking okra have already been reported in Brazil, and some of them can cause plant death. The correct identification of Meloidogyne species and, or races infecting okra roots is mandatory for choosing appropriate control measures. To determine the occurrence and distribution of Meloidogyne spp. and other nematodes in the area of the East of MG, 70 soil and root samples coming from 14 municipalities were appraised for morphological and isoenzymatic characteristics. Among the populations of Meloidogyne spp., M. incognita (Esterase phenotypes I1 and I2 prevailed and were followed by M. javanica (phenotypes J2 and J3 and M. arenaria (phenotypes A2. The species M. mayaguensis was confirmed by the phenotypes: esterase (M2, malate dehydrogenase (N3, superoxide dismutase (N2 and glutamate oxaloacetate transaminase (N3. This is the first report of the M. mayaguensis occurrence in MG. Other nematodes associated with the okra plants were Aphelenchus sp., Criconemella sp., Helicotylenchus spp., Pratylenchus brachyurus and P. coffeae, Rotylenchulus reniformis, Rotylenchus sp., Tylenchus sp. and Tylenchorhynchus sp.

  6. Dicty_cDB: AFN775 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available nts: (bits) Value N BM774584 |BM774584.1 ra95c11.y1 Meloidogyne incognita egg pAMP1 Bird Meloidogyne incogni...s mellifera cDNA clone BB170011A20F01 5', mRNA sequence. 64 6e-08 2 AW827814 |AW827814.1 ra59b10.y1 Bird-Rao... mRNA sequence. 48 5e-07 3 AW871572 |AW871572.1 ra79e06.y1 Bird-Rao Meloidogyne i

  7. Effects of temperature on the life-history traits of Sancassania (Caloglyphus) berlesei (Acari: Astigmatina: Acaridae) feeding on root-knot nematodes, Meloidogyne spp. (Nematoda: Meloidogynidae).

    Science.gov (United States)

    Abou El-Atta, Doaa Abd El-Maksoud; Ghazy, Noureldin Abuelfadl; Osman, Mohamed Ali

    2014-11-01

    Sancassania (Caloglyphus) berlesei (Michael) is a cosmopolitan and free-living mite that inhabits soil as well as laboratory colonies of insects and fungi and may have a role as a biocontrol agent of nematodes. In this study, we investigated the effects of temperature on the development, reproduction, and food consumption of S. berlesei fed egg masses of root-knot nematodes, Meloidogyne spp., an important group of agricultural pests. Mites were reared at 20, 25 or 30 °C in the dark. The mites could feed on the nematode egg masses, and their developmental time decreased at higher temperatures. Time from the egg to adult was similar in females and males reared at the same temperature. Adult females lived longer than males at 25 °C, but not at 20 or 30 °C. Generally, females showed a higher rate of food consumption than males. Females laid the largest number of eggs at 20 and 25 °C (199.7 and 189.8 eggs/female, respectively), but the intrinsic rate of natural increase was highest at 30 °C (r m = 0.29). In comparing our data with previous reports, we noted that S. berlesei that fed on egg masses of root-knot nematodes showed a longer developmental time and a lower reproductive rate than Sancassania mites that fed on other diets. Nonetheless, the relatively high value of r m (e.g., at 25 and 30 °C) suggests that this mite may have certain advantages as a biocontrol agent of root-knot nematodes.

  8. Detection and quantification of root-knot nematode (Meloidogyne javanica), lesion nematode (Pratylenchus zeae) and dagger nematode (Xiphinema elongatum) parasites of sugarcane using real-time PCR.

    Science.gov (United States)

    Berry, Shaun D; Fargette, Mireille; Spaull, Vaughan W; Morand, Serge; Cadet, Patrice

    2008-06-01

    A number of different plant parasitic nematode species are found associated with sugarcane in South Africa. Of these, the root-knot nematode (Meloidogyne javanica), the lesion nematode (Pratylenchus zeae) and the dagger nematode (Xiphinema elongatum) are potentially the most damaging pests. Identification and enumeration of the number of these nematodes are necessary for providing advice to farmers as well as studying the effects of various treatments in field and glasshouse trials. We report on the development, use, and extent of specificity of three sets of primers, for M. javanica, P. zeae and X. elongatum, and on tests to detect and quantify the number of these nematodes in soil samples using SYBR Green I dye and real-time PCR technology. Amplicons from the three target species (obtained with their respective primer sets) are discernible in size by gel electrophoresis (380bp for M. javanica, 250bp for P. zeae and 500bp for X. elongatum). Also, these amplicons have characteristic melting temperatures of 83.8 degrees C (M. javanica), 86.6 degrees C (P. zeae) and 86.1 degrees C (X. elongatum). Investigations into multiplex reactions found competition between species with M. javanica competing with P. zeae and X. elongatum. Subsequent single tube (simplex) assays, enabled the construction of calibration curves for each of the three species. These were then used for quantification of the numbers of each of these species in nematode samples extracted from the field, with a high (R2=0.83) and significant positive correlation between real-time PCR and counts performed with microscopy.

  9. Efeito de extratos proteicos de amendoim sobre o desenvolvimento, a capacidade infectiva e atividade de enzimas proteolíticas de Meloidogyne enterolobii

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    Juliana Martins Ribeiro

    2014-06-01

    Full Text Available No Brasil, Meloidogyne enterolobii vem causando perdas significativas na produção de goiabeiras e, no submédio do Vale do São Francisco, por exemplo, o impacto negativo decorrente da infecção e morte de goiabeiras tem refletido diretamente na qualidade de vida dos agricultores. Até o momento, não existem métodos de controle efetivos: os nematicidas avaliados experimentalmente não têm sido eficientes e não há produtos registrados no Ministério da Agricultura, Pecuária e Abastecimento para aplicação em goiabeiras. Assim, há necessidade de realizar pesquisa básica nesta área. A prospecção de proteínas relacionadas com a resistência em espécies resistentes pode ser uma alternativa para o desenvolvimento de medidas para seu controle. Para isso, foram realizados ensaios biológicos de toxicidade para a análise do efeito de extratos proteicos de amendoim sobre o desenvolvimento, a capacidade infectiva e atividade de enzimas proteolíticas de M. enterolobii visando à identificação de proteínas com potencial para controle desse nematoide. Os resultados obtidos indicaram que o extrato proteico total de amostras de raízes de plantas de amendoim inoculadas não tem efeito sobre as três características supracitadas. Sendo assim, são necessários estudos dessa natureza com outras espécies resistentes ao patógeno visando à identificação de proteínas que apresentem potencial para o seu controle.

  10. Occurrence, Parasitism, and Pathogenicity of Nematodes Associated with Sycamore (Platanus occidentalis L.).

    Science.gov (United States)

    Churchill, R C; Ruehle, J L

    1971-04-01

    Ten species of stylet-bearing nematodes were recovered in a survey of sycamore (Platanus occidentalis L. ) stands in Georgia. Helicotylenchus, Xiphinema, and Criconemoides were the genera found most frequently. Populations of Hoplolaimus galeatus, Scutellonema brachyurum, Helicotylenchus dihystera and H. pseudorobustus increased on greenhouse-grown sycamore, but Trichodorus christiei, Xiphinema americanum, Meloidogyne hapla, M. arenaria and M. incognita did not. Hoplolaimus galeatus and S. brachyurum are semi-endoparasites; H. dihystera and H. pseudorobustus are migratory endoparasites. Hoplolaimus galeatus caused extensive root necrosis and marked decrease of fresh weights of seedling roots and tops. Helicotylenchus dihystera and S. brachyurum produced only qualitatively different sparse and unhealthy root growth. Helicotylenchus pseudorobustus caused only a reduction in root surface area.

  11. Linhagens de alface-crespa para o verão resistentes ao Meloidogyne javanica e ao vírus mosaico-da-alface Lineages of crisp-leaf lettuce for summer cropping resistant to Meloidogyne javanica and to Lettuce mosaic virus

    Directory of Open Access Journals (Sweden)

    Renata Rodrigues Silva

    2008-10-01

    Full Text Available O objetivo deste trabalho foi selecionar famílias F4 de alface, oriundas do cruzamento entre as cultivares Verônica e Salinas 88, para o cultivo no verão, com relação ao tipo de folha, e à resistência ao Lettuce mosaic virus (LMV e ao nematóide-das-galhas Meloidogyne javanica. Primeiramente, avaliaram-se a coloração da folha, tipos de borda e limbo foliares, além da tolerância ao calor no campo, em blocos ao acaso compostos pelas 15 famílias F4 previamente selecionadas, pelas cultivares parentais e pela cultivar testemunha Regina 71 (folhas lisas e tolerante ao calor, com cinco repetições e oito plantas por parcela. Na segunda etapa, as famílias foram avaliadas quanto à resistência ao LMV e ao nematóide-das-galhas, em bandejas de 128 células acondicionadas em estufa. As médias das notas atribuídas a cada família foram comparadas às médias de cada cultivar parental pelo teste de Dunnet (5%. A família AFX007B-140-21, homozigota resistente aos nematóides e ao LMV e, também, tolerante ao calor, foi a mais promissora. O cruzamento entre uma cultivar de folhas crespas e soltas com uma de folhas crespas e repolhuda, pode originar linhagens promissoras tanto de folhas crespas quanto de folhas lisas.The aim of this work was to select F4 lettuce families, derived from the cross 'Veronica' x 'Salinas 88 ', for summer cropping, type of leaves, and for resistance to Meloidogyne javanica and to Lettuce mosaic virus (LMV. First, evaluations were made for leaf colour, leaf limb, border type, and heat tolerance in the field, in a complete blocks desing, in 15 F4 families previously selected, parent cultivars and, as control, the cultivar Regina 71 (butterleaf and tolerant to heat. Five replicates and eight plants per plot were used. As second step, the families were evaluated in greenhouse, in 128-cell expanded polystyrene trays, for resistance to LMV and root-knot nematodes. Score means of each family were compared to the means of

  12. Evaluation of edible ginger and turmeric cultivars for root-knot nematode resistance

    Science.gov (United States)

    Edible ginger and turmeric roots are important agricultural commodities for the State of Hawaii. Bacterial wilt, Ralstonia solanacearum, and root-knot nematodes, Meloidogyne spp. are major factors hindering optimum production. An evaluation of tolerance and resistance to M. incognita was undertake...

  13. Screening edible ginger and turmeric cultivars for resistance to root-knot nematodes

    Science.gov (United States)

    Twenty-two edible ginger and turmeric cultivars were screened for resistance or tolerance to Meloidogyne incognita. Plants were raised in 66 L grow bags in greenhouses in Hawaii according to established practices for producing bacterial wilt-free ginger. Three months after planting, each grow bag ...

  14. Genome Sequence of Delftia acidovorans HK171, a Nematicidal Bacterium Isolated from Tomato Roots

    Science.gov (United States)

    Han, Jae Woo; Oh, Mira; Choi, Gyung Ja

    2017-01-01

    ABSTRACT Delftia acidovorans strain HK171, isolated from tomato roots, exhibited nematicidal activity against Meloidogyne incognita. Here, we present the genome sequence of D. acidovorans strain HK171, which consists of one circular chromosome of 6,430,384 bp, with 66.9% G+C content. PMID:28254991

  15. Maintenance of genetic variation in automictic root-knot nematodes

    NARCIS (Netherlands)

    Van Der Beek, J. G. ( Hans); Punacker, Laas P.

    2008-01-01

    Differences in amplified fragment length polymorphisms (AFLP) between isolates and between mono-female lines of facultative automictic Meloidogyne hapla race A and obligate apomictic M incognita were determined to test the hypothesis that inverted meiosis occurs. DNA of the parthenogenetic nematode

  16. SUPPRESSION OF DAMPING-OFF OF CUCUMBER CAUSED BY PYTHIUM ULTIMUM WITH LIVE CELLS AND EXTRACTS OF SERRATIA MARCESCENS N4-5

    Science.gov (United States)

    Environmentally friendly control measures are needed for the soilborne pathogens Pythium ultimum and Meloidogyne incognita. These pathogens can cause severe losses to field- and greenhouse-grown cucumber and other cucurbits. Live cells and ethanol extracts of cultures of the bacterium Serratia mar...

  17. Does infection by southern root-knot nematode influence development of Phytophthora blight in pepper?

    Science.gov (United States)

    The southern root-knot nematode, Meloidogyne incognita, and Phytophthora capsici, the causal agent of Phytophthora blight, are both important pathogens of pepper (Capsicum annuum L.) in the U.S. and worldwide. Although there is significant information in the literature about the responses of pepper...

  18. Evaluation of Variable Rate Application of Nematicides in Cotton According to Nematode Risk Zones

    Science.gov (United States)

    Cotton (Gossypium hirsutum L.) lint yield losses by southern root-knot nematode [Meloidogyne incognita] (RKN) have increased during the last 20 years. Site-specific management (SSM) of nematicides is a promising method to reduce yield losses, increase profitability and reduce adverse environmental i...

  19. Cotton Yield Response to Variable Rate Nematicides According to Risk Zones

    Science.gov (United States)

    Cotton (Gossypium hirsutum L.) lint yield losses by southern root-knot nematode [Meloidogyne incognita] (RKN) have increased during the last 20 years. Site-specific management (SSM) of nematicides is a promising method to reduce yield losses, increase profitability and reduce adverse environmental i...

  20. Biologische grondontsmetting bij de teelt van trekheesters: Implementatie van een alternatieve ontsmettingsmerhode in de praktijk

    NARCIS (Netherlands)

    Ludeking, D.J.W.; Hamelink, R.; Bloemhard, C.M.J.; Slooten, van M.A.

    2011-01-01

    In dit onderzoek is gekeken naar de effectiviteit van de toepassing van het product Herbie7022 op Verticillium dahliae, Meloidogyne incognita en engerlingen van de roestbruine bladsprietkever Serica brunnea. Alle engerlingen van Serica brunnea zijn dood na het spitten en afdekken van het perceel. An

  1. Counting Populations

    Science.gov (United States)

    Damonte, Kathleen

    2004-01-01

    Scientists use sampling to get an estimate of things they cannot easily count. A population is made up of all the organisms of one species living together in one place at the same time. All of the people living together in one town are considered a population. All of the grasshoppers living in a field are a population. Scientists keep track of the…

  2. Species of Root-knot Nematodes and Fungal Egg Parasites Recovered from Vegetables in Almería and Barcelona, Spain.

    Science.gov (United States)

    Verdejo-Lucas, S; Ornat, C; Sorribas, F J; Stchiegel, A

    2002-12-01

    Intensive vegetable production areas were surveyed in the provinces of Almería (35 sites) and Barcelona (22 sites), Spain, to determine the incidence and identity of Meloidogyne spp. and of fungal parasites of nematode eggs. Two species of Meloidogyne were found in Almería-M. javanica (63% of the samples) and M. incognita (31%). Three species were found in Barcelona, including M. incognita (50%), M. javanica (36%), and M. arenaria (14%). Solanaceous crops supported larger (P parasites were found in 37% and 45% of the sites in Almería and Barcelona, respectively, but percent parasitism was never greater than 5%. Nine fungal species were isolated from single eggs of the nematode. The fungi included Verticillium chlamydosporium, V. catenulatum, Fusarium oxysporum, F. solani, Fusarium spp., Acremonium strictum, Gliocladium roseum, Cylindrocarpon spp., Engiodontium album, and Dactylella oviparasitica. Two sterile fungi and five unidentified fungi also were isolated from Meloidogyne spp. eggs.

  3. Host genetic resistance to root-knot nematodes, Meloidogyne spp., in Solanaceae: from genes to the field.

    Science.gov (United States)

    Barbary, Arnaud; Djian-Caporalino, Caroline; Palloix, Alain; Castagnone-Sereno, Philippe

    2015-12-01

    Root-knot nematodes (RKNs) heavily damage most solanaceous crops worldwide. Fortunately, major resistance genes are available in a number of plant species, and their use provides a safe and economically relevant strategy for RKN control. From a structural point of view, these genes often harbour NBS-LRR motifs (i.e. a nucleotide binding site and a leucine rich repeat region near the carboxy terminus) and are organised in syntenic clusters in solanaceous genomes. Their introgression from wild to cultivated plants remains a challenge for breeders, although facilitated by marker-assisted selection. As shown with other pathosystems, the genetic background into which the resistance genes are introgressed is of prime importance to both the expression of the resistance and its durability, as exemplified by the recent discovery of quantitative trait loci conferring quantitative resistance to RKNs in pepper. The deployment of resistance genes at a large scale may result in the emergence and spread of virulent nematode populations able to overcome them, as already reported in tomato and pepper. Therefore, careful management of the resistance genes available in solanaceous crops is crucial to avoid significant reduction in the duration of RKN genetic control in the field. From that perspective, only rational management combining breeding and cultivation practices will allow the design and implementation of innovative, sustainable crop production systems that protect the resistance genes and maintain their durability.

  4. Promoting Population

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    THE world's population reached 5 billion in 1987,then 6 billion in 1999;now,in 2011,it is 7 billion.For a country with a set birth control policy,the way in which Chinese people and the media view this number has greatly changed.People are increasingly reflecting on the concept of population from a more scientific and rational perspective.This shift is a change from how people perceived population in the past.

  5. Evaluation of 31 Potential Biofumigant Brassicaceous Plants as Hosts for Three Meloiodogyne Species

    Science.gov (United States)

    Edwards, Scott; Ploeg, Antoon

    2014-01-01

    Brassicaceous cover crops can be used for biofumigation after soil incorporation of the mowed crop. This strategy can be used to manage root-knot nematodes (Meloidogyne spp.), but the fact that many of these crops are host to root-knot nematodes can result in an undesired nematode population increase during the cultivation of the cover crop. To avoid this, cover crop cultivars that are poor or nonhosts should be selected. In this study, the host status of 31 plants in the family Brassicaceae for the three root-knot nematode species M. incognita, M. javanica, and M. hapla were evaluated, and compared with a susceptible tomato host in repeated greenhouse pot trials. The results showed that M. incognita and M. javanica responded in a similar fashion to the different cover cultivars. Indian mustard (Brassica juncea) and turnip (B. rapa) were generally good hosts, whereas most oil radish cultivars (Raphanus. sativus ssp. oleiferus) were poor hosts. However, some oil radish cultivars were among the best hosts for M. hapla. The arugula (Eruca sativa) cultivar Nemat was a poor host for all three nematode species tested. This study provides important information for chosing a cover crop with the purpose of managing root-knot nematodes. PMID:25276003

  6. Evaluation of 31 potential biofumigant brassicaceous plants as hosts for three meloiodogyne species.

    Science.gov (United States)

    Edwards, Scott; Ploeg, Antoon

    2014-09-01

    Brassicaceous cover crops can be used for biofumigation after soil incorporation of the mowed crop. This strategy can be used to manage root-knot nematodes (Meloidogyne spp.), but the fact that many of these crops are host to root-knot nematodes can result in an undesired nematode population increase during the cultivation of the cover crop. To avoid this, cover crop cultivars that are poor or nonhosts should be selected. In this study, the host status of 31 plants in the family Brassicaceae for the three root-knot nematode species M. incognita, M. javanica, and M. hapla were evaluated, and compared with a susceptible tomato host in repeated greenhouse pot trials. The results showed that M. incognita and M. javanica responded in a similar fashion to the different cover cultivars. Indian mustard (Brassica juncea) and turnip (B. rapa) were generally good hosts, whereas most oil radish cultivars (Raphanus. sativus ssp. oleiferus) were poor hosts. However, some oil radish cultivars were among the best hosts for M. hapla. The arugula (Eruca sativa) cultivar Nemat was a poor host for all three nematode species tested. This study provides important information for chosing a cover crop with the purpose of managing root-knot nematodes.

  7. Effect of local tree seeds in the control of root knot nematode Meloidogyne javanica (Treub chitwood and growth promotion of chickpea (Cicer arietinum L. and mung bean (Vigna radiata L.

    Directory of Open Access Journals (Sweden)

    Zainab M. Ahmed

    2012-12-01

    Full Text Available Seeds of local trees, such Azadirachta indica A. Juss, Adenanthera pavonina L., Leucaena leucocephala (Lam. de Wit and Eucalyptus spp., were used as aqueous extract at 25, 50 and 100 % concentration to control the activity of Meloidogyne javanica (Treub Citwood. All seed extracts showed lethal effect on M. javanica eggs, and a gradual decrease in egg hatching and an increase in mortality of second-stage juveniles were observed with the increase in extract concentration. L. leucocephala was found to be most effective in reducing egg hatching, whereas 100 % mortality of juveniles was observed in the case of A. indica seed extract. Number of knots was significantly reduced at 100 % concentration when seeds of chick pea and mung bean were treated and soil was drenched with A. pavonina and Eucalyptus spp. seed extract.

  8. Evaluation of plant aqueous extracts, added into the soil, on Meloidogyne javanica (Treub, 1885 Chitwood, 1949 / Avaliação de extratos aquosos de várias espécies vegetais, aplicados ao solo, sobre Meloidogyne javanica (Treub, 1885 Chitwood, 1949

    Directory of Open Access Journals (Sweden)

    Leandro Grassi de Freitas

    2009-10-01

    Full Text Available The use of plant extracts with nematicidal properties to control plant nematodes can be a useful alternative to small farmers, regarding its low cost and non-toxic effects. The effect of the addition into the soil of aqueous extracts of 20 plant species on Meloidogyne javanica in plants of tomato was studied at greenhouse conditions. These were divided into two groups and evaluated in two separate experiments.The soil in the 2.0 L pots was infested with 5,000 eggs and, in the same day, it was applied 20 mL of aqueous extracts of the 20 plant species (Chrysanthemum parthenium, Arctium lappa, Cymbopogon citratus, Bacharis trimera, Equisetum sp., Melia azedarach, Mentha sp., Ricinus communis, Ocimum basilicum, Momordica charantia, Ruta graveolens, Coleus barbatus, Symphitum officinalis, Polygonum acre, Canavalia ensiformis, Foeniculum vulgare, Petiveria alliacea, Ageratum conyzoides, Mucuna pruriens and Azadirachta indica. Distilled water was used as control. Sixty days later, were evaluated for plant height, the fresh weight of shoot and root and the numbers of galls and eggs per root system. The extracts of Mentha sp., Arctium lappa and Ricinus communis reduced the number of galls of M. javanica in 75.6%; 65.7% and 54.4%; and the number of eggs in 81.7%, 75.9% and 56.6%, respectively.O uso de extratos vegetais com propriedades nematicidas no controle de fitonematóides representa mais uma alternativa para os pequenos produtores, com valor prático e econômico, e sem riscos de contaminação do ambiente. A adição ao solo dos extratos aquosos de 20 espécies de plantas foi avaliada sobre a população de Meloidogyne javanica em plantas de tomateiro, em casa de vegetação. Estas foram divididas em dois grupos e avaliadas em dois experimentos separados. No mesmo dia em que se infestou o solo com 5.000 ovos do nematóide, adicionou-se 20 mL dos extratos aquosos obtidos de folhas de artemísia (Chrysanthemum parthenium, bardana (Arctium lappa

  9. Soil amendment with chopped or ground dry leaves of six species of plants for the control of Meloidogyne javanica in tomato under greenhouse conditions Incorporação ao solo de folhas secas picadas ou moídas de seis espécies de plantas para o controle de Meloidogyne javanica em tomateiro em casa de vegetação

    Directory of Open Access Journals (Sweden)

    Everaldo Antônio Lopes

    2011-06-01

    Full Text Available Greenhouse experiments were conducted to evaluate the effect of soil amendment with chopped (1cm² or ground (1mm sieve dry leaves of assa-peixe (Vernonia polyanthes, lemon-grass (Cymbopogon citratus, eucalyptus (Eucalyptus citriodora, castor (Ricinus communis, mango (Mangifera indica or neem (Azadirachta indica for the control Meloidogyne javanica. Into the soil (Yellow red oxisol of each pot were added leaves (5g kg-1 of soil and 5,000 eggs of the nematode. After seven days, one tomato seedling "Santa Cruz Kada" was transplanted to each pot. The tomato root weight, galls and eggs/root system were determined 60 days after transplant. None of the soil amendments reduced gall or eggs, when applied as leaf pieces. However, all tested plant species reduced the gall number, when they were incorporated into the soil as powder, and maximum nematode suppression occurred in soil amended with neem leaves (61%. The amendment with ground leaves of castor, neem, eucalyptus and lemon-grass reduced the number of eggs, with maximum reduction occurring in soil amended with ground castor leaves (69%, evidencing that these organic amendments can be an alternative for M. javanica control in tomato. Further studies are required under field conditions to confirm the potential of these organic amendments on the control of M. javanica.Experimentos em casa de vegetação foram conduzidos com o objetivo de avaliar o efeito da adição ao solo de folhas secas picadas (1cm² ou trituradas (peneira de 1mm de assa-peixe (Vernonia polyanthes, capim-limão (Cymbopogon citratus, eucalipto (Eucalyptus citriodora, mamona (Ricinus communis, manga (Mangifera indica ou nim (Azadirachta indica para o controle de Meloidogyne javanica. Ao solo de cada vaso (latossolo vermelho-amarelo, foram adicionadas folhas (5g kg-1 de solo e 5.000 ovos do nematoide. Após sete dias, uma muda de tomateiro "Santa Cruz Kada" foi transplantada em cada vaso. O peso das raízes e os números de galhas e

  10. Population Blocks.

    Science.gov (United States)

    Smith, Martin H.

    1992-01-01

    Describes an educational game called "Population Blocks" that is designed to illustrate the concept of exponential growth of the human population and some potential effects of overpopulation. The game material consists of wooden blocks; 18 blocks are painted green (representing land), 7 are painted blue (representing water); and the remaining…

  11. Long-term in vitro system for maintenance and amplification of root-knot nematodes in Cucumis sativus roots

    Directory of Open Access Journals (Sweden)

    Fernando E. eDíaz-Manzano

    2016-02-01

    Full Text Available Root-knot nematodes (RKN are polyphagous plant-parasitic roundworms that produce large crop losses, representing a relevant agricultural pest worldwide. After infection, they induce swollen root structures called galls containing giant cells (GCs indispensable for nematode development. Among efficient control methods are biotechnology-based strategies that require a deep knowledge of underlying molecular processes during the plant-nematode interaction. Methods of achieving this knowledge include the application of molecular biology techniques such as transcriptomics (massive sequencing or microarray hybridization, proteomics or metabolomics. These require aseptic experimental conditions, as undetected contamination with other microorganisms could compromise the interpretation of the results. Herein, we present a simple, efficient and long-term method for nematode amplification on cucumber roots grown in vitro. Amplification of juveniles (J2 from the starting inoculum is around 40-fold. The method was validated for three Meloidogyne species (M. javanica, M. incognita and M. arenaria, producing viable and robust freshly hatched J2s. These can be used for further in vitro infection of different plant species such as Arabidopsis, tobacco and tomato, as well as enough J2s to maintain the population. The method allowed maintenance of around 90 Meloidogyne spp. generations (one every two months from a single initial female over 15 years.

  12. Imaginary populations

    Directory of Open Access Journals (Sweden)

    A. Martínez–Abraín

    2010-01-01

    Full Text Available A few years ago, Camus & Lima (2002 wrote an essay to stimulate ecologists to think about how we define and use a fundamental concept in ecology: the population. They concluded, concurring with Berryman (2002, that a population is "a group of individuals of the same species that live together in an area of sufficient size to permit normal dispersal and/or migration behaviour and in which population changes are largely the results of birth and death processes". They pointed out that ecologists often forget "to acknowledge that many study units are neither natural nor even units in terms of constituting a population system", and hence claimed that we "require much more accuracy than in past decades in order to be more effective to characterize populations and predict their behaviour". They stated that this is especially necessary "in disciplines such as conservation biology or resource pest management, to avoid reaching wrong conclusions or making inappropriate decisions". As a population ecologist and conservation biologist I totally agree with these authors and, like them, I be¬lieve that greater precision and care is needed in the use and definition of ecological terms. The point I wish to stress here is that we ecologists tend to forget that when we use statistical tools to infer results from our sample to a population we work with what statisticians term "imaginary", "hypothetical" or "potential" popula¬tions. As Zar (1999 states, if our sample data consist of 40 measurements of growth rate in guinea pigs "the population about which conclusions might be drawn is the growth rates of all the guinea pigs that conceivably might have been administered the same food supplement under identical conditions". Such a population does not really exist, and hence it is considered a hypothetical or imaginary population. Compare that definition with the population concept that would be in our minds when performing such measurements. We would probably

  13. Population policy.

    Science.gov (United States)

    1987-03-01

    Participants in the Seminar on Population Policies for Top-level Policy Makers and Program Managers, meeting in Thailand during January 1987, examined the challenges now facing them regarding the implementation of fertility regulation programs in their respective countries -- Bangladesh, China, India, Indonesia, Malaysia, Nepal, Pakistan, the Philippines, the Republic of Korea, and Thailand. This Seminar was organized to coincide with the completion of an Economic and Social Commission for Asia and the Pacific (ESCAP) study investigating the impact and efficiency of family planning programs in the region. Country studies were reviewed at the Seminar along with policy issues about the status of women, incentive and disincentive programs, and socioeconomic factors affecting fertility. In Bangladesh the government recognizes population growth as its top priority problem related to the socioeconomic development of the country and is working to promote a reorientation strategy from the previous clinic-oriented to a multidimensional family welfare program. China's family planning program seeks to postpone marraige, space the births of children between 3-5 years, and promote the 1-child family. Its goal is to reduce the rate of natural increase from 12/1000 in 1978 to 5/1000 by 1985 and 0 by 2000. India's 7th Five-Year-Plan (1986-90) calls for establishing a 2-child family norm by 2000. In Indonesia the government's population policy includes reducing the rate of population growth, achieving a redistribution of the population, adjusting economic factors, and creating prosperous families. The government of Indonesia reversed its policy to reduce the population growth rate in 1984 and announced its goal of achieving a population of 70 million by 2100 in order to support mass consumption industries. It has created an income tax deduction system favoring large families and maternity benefits for women who have up to 5 children as incentives. Nepal's official policy is to

  14. Variabilidade genética de acessos de araçazeiro e goiabeira suscetíveis e resistentes a Meloidogyne enterolobii

    Directory of Open Access Journals (Sweden)

    Aline das Graças Souza

    2014-05-01

    Full Text Available A goiabeira representa uma importante atividade frutícola no Brasil, com mercado cada vez maior. Porém, desde 1989 vêm sendo relatados severos danos à cultura, causados pelo nematóide Meloidogyne enterolobii. Uma das alternativas para solucionar esse problema é a utilização de porta-enxertos com resistência a este patógeno. Este trabalho teve por objetivo a caracterização molecular, com marcadores RAPD, de acessos de Psidium testados quanto à resistência a M. enterolobii e quanto à compatibilidade como porta-enxertos para as goiabeiras comerciais. Foram testados 30 primers, dos quais 19 forneceram resultados nítidos para a amplificação. Foram gerados 163 fragmentos, dos quais 86 polimórficos (63,0%. Em média, cada iniciador produziu 8,6 fragmentos, dos quais 5,4 apresentaram polimorfismo. A análise de agrupamento foi realizada por espécie, os acessos de Psidium sp apresentaram a formação de dois grupos, um formado pelo acesso A-UFLA e o segundo subdividido em quatro subgrupos, sendo os acessos com maiores distâncias genéticas A-Ufla, resistente a M. enterolobii, A-Ufla4 e A-Ufla5, ambos suscetíveis ao nematoide em questão, todos coletados em Lavras-MG, com similaridade aproximada de 66%. Na análise de agrupamento, dos treze acessos de P.cattleyanum, foi possível constatar a formação de dois grandes grupos. Um formado por três acessos suscetíveis a M. enterolobii (A-20.2, A-10.1 e A-9.2 e outro grupo formado por dez acessos. Os acessos se agruparam, conforme a região de origem, em seis grupos, sendo que o mais divergente é originário da região de Lavras - MG, com 0,65 de similaridade, onde as distâncias genéticas variaram de 0,88 a 0,65. Dos treze acessos de P. guineense, todos suscetíveis a M. enterolobii, sendo 12 oriundos de Recife e um de Pelotas (A-14.1 e agruparam-se em dois grupos com similaridades variando de 0,59 a 0,83. Quanto ao estudo de diversidade entre os acessos de goiabeiras, a maior dist

  15. [Population education].

    Science.gov (United States)

    Niang, M

    1992-12-01

    Africa has the highest population growth rate in the world (3%). It has 650 million people (about 900 million in 2000). Rapid population growth has serious consequences which, if not addressed, will be disastrous. This worrisome situation has led some governments to adopt demographic policies to slow down population growth. The UN Economic, Scientific and Cultural Organization (UNESCO) recommends that schools provide population education. Various population conferences have popularized population education in schools among African countries. UNESCO began its regional program on population education in Africa in 1969. National family life and population education (FL/PE) projects have increased from 4 in 1970 to 32 in 1990 (17 in French- and Portuguese-speaking Africa and 5 in English-speaking Africa). These projects teach students about the links between demographic problems and socioeconomic factors and contemporary culture. They aim for total development of the individual and improvement of the quality of life for the individual, family, and community. Topics covered in FL/PE are birth rate; fertility; health; and maternal, infant, and child mortality; unwanted pregnancy; illegal abortion; sexually transmitted diseases; rural-urban migration; and urbanization. Benin introduced FL/PE at all levels of its education system while Senegal, Guinea, Mauritania, and Zaire introduced it to only the primary and secondary school levels. Some countries teach FL/PE as one discipline while most countries (e.g., Senegal) have integrated it into other disciplines (e.g., geography). FL/PE should begin in primary schools because they have the most students and prepare students for middle schools, which provide FL/PE. Elementary education in Senegal is being overhauled to introduce current major problems bit by bit. Senegal also wants to incorporate FL/PE into literacy and adult education programs. Integration of FL/PE into other disciplines should be encouraged.

  16. Population dynamics

    Directory of Open Access Journals (Sweden)

    Cooch, E. G.

    2004-06-01

    Full Text Available Increases or decreases in the size of populations over space and time are, arguably, the motivation for much of pure and applied ecological research. The fundamental model for the dynamics of any population is straightforward: the net change over time in the abundance of some population is the simple difference between the number of additions (individuals entering the population minus the number of subtractions (individuals leaving the population. Of course, the precise nature of the pattern and process of these additions and subtractions is often complex, and population biology is often replete with fairly dense mathematical representations of both processes. While there is no doubt that analysis of such abstract descriptions of populations has been of considerable value in advancing our, there has often existed a palpable discomfort when the ‘beautiful math’ is faced with the often ‘ugly realities’ of empirical data. In some cases, this attempted merger is abandoned altogether, because of the paucity of ‘good empirical data’ with which the theoretician can modify and evaluate more conceptually–based models. In some cases, the lack of ‘data’ is more accurately represented as a lack of robust estimates of one or more parameters. It is in this arena that methods developed to analyze multiple encounter data from individually marked organisms has seen perhaps the greatest advances. These methods have rapidly evolved to facilitate not only estimation of one or more vital rates, critical to population modeling and analysis, but also to allow for direct estimation of both the dynamics of populations (e.g., Pradel, 1996, and factors influencing those dynamics (e.g., Nichols et al., 2000. The interconnections between the various vital rates, their estimation, and incorporation into models, was the general subject of our plenary presentation by Hal Caswell (Caswell & Fujiwara, 2004. Caswell notes that although interest has traditionally

  17. Stellar Populations

    NARCIS (Netherlands)

    Peletier, Reynier F.

    2013-01-01

    This is a summary of my lectures during the 2011 Canary Islands Winter School in Puerto de la Cruz. I give an introduction to the field of stellar populations in galaxies, and highlight some new results. Since the title of the Winter School is Secular Evolution in Galaxies I mostly concentrate on ne

  18. Effect of Emamectin Benzoate on Root-Knot Nematodes and Tomato Yield.

    Directory of Open Access Journals (Sweden)

    Xingkai Cheng

    Full Text Available Southern root-knot nematode (Meloidogyne incognita is an obligate, sedentary endoparasite of more than 3000 plant species, that causes heavy economic losses and limit the development of protected agriculture of China. As a biological pesticide, emamectin benzoate has effectively prevented lepidopteran pests; however, its efficacy to control M. incognita remains unknown. The purpose of the present study was to test soil application of emamectin benzoate for management of M. incognita in laboratory, greenhouse and field trials. Laboratory results showed that emamectin benzoate exhibited high toxicity to M. incognita, with LC50 and LC90 values 3.59 and 18.20 mg L(-1, respectively. In greenhouse tests, emamectin benzoate soil application offered good efficacy against M. incognita while maintaining excellent plant growth. In field trials, emamectin benzoate provided control efficacy against M. incognita and resulted in increased tomato yields. Compared with the untreated control, there was a 36.5% to 81.3% yield increase obtained from all treatments and the highest yield was received from the highest rate of emamectin benzoate. The results confirmed that emamectin benzoate has enormous potential for the control of M. incognita in tomato production in China.

  19. Stickleback Population

    Directory of Open Access Journals (Sweden)

    Ulrika Candolin

    2012-01-01

    Full Text Available Human-induced eutrophication has increased offspring production in a population of threespine stickleback Gasterosteus aculeatus in the Baltic Sea. Here, we experimentally investigated the effects of an increased density of juveniles on behaviours that influence survival and dispersal, and, hence, population growth—habitat choice, risk taking, and foraging rate. Juveniles were allowed to choose between two habitats that differed in structural complexity, in the absence and presence of predators and conspecific juveniles. In the absence of predators or conspecifics, juveniles preferred the more complex habitat. The preference was further enhanced in the presence of a natural predator, a perch Perca fluviatilis (behind a transparent Plexiglas wall. However, an increased density of conspecifics relaxed the predator-enhanced preference for the complex habitat and increased the use of the open, more predator-exposed habitat. Foraging rate was reduced under increased perceived predation risk. These results suggest that density-dependent behaviours can cause individuals to choose suboptimal habitats where predation risk is high and foraging rate low. This could contribute to the regulation of population growth in eutrophicated areas where offspring production is high.

  20. Population aging.

    Science.gov (United States)

    1999-04-01

    This paper focuses on the impact of population aging in China, the most densely populated country in the world. Statistics indicate that by the end of 1998, 83.75 million out of the 1.248 billion Chinese people will be over 65 years old. According to the UN standards, China will soon become an aging society. The aging population poses several challenges to the country with the greatest challenge being the increasing social responsibility to care for the aged. With the undeveloped legislative framework to protect the interests of the aged and the serious drawbacks in the pension system to cater only to the income part and not the service part of the aged, China is not yet ready for the advent of aging. Violation of the rights of senior citizens is still very rampant despite enactment of the law on Protection of the Rights of the Elderly in 1996. Moreover, China is not economically ready to become an aging society. China faces this challenge by adopting a three-pronged approach to solve the problem namely: family support, establishment of nursing homes, and creating a social security framework that addresses the needs of the society suited to the Chinese condition. It is believed that with the growing economy of the country and the rising income of its people, a comprehensive social security net will be created to take care of the aged.

  1. Soil properties influencing phytoparasitic nematode population on Chilean vineyards Propiedades del suelo que influyen en la población de nematodos fitoparásitos en viñedos de Chile

    Directory of Open Access Journals (Sweden)

    Mario Fajardo P

    2011-06-01

    Full Text Available Lifecycle of phytoparasitic nematode takes place in the rhizosphere, therefore their breeding, parasitism and mobility dynamics are inevitably influenced by the soil-root interaction, A study was performed to evaluate the influence of Vitis rootstocks to some plant parasitic nematodes under different soil conditions. Nematode populations were assessed in Vitis vinifera L. var ‘Chardonnay’ plants grafted on two rootstocks (K5BB, SO4 and ungrafted ‘Chardonnay’ as a control in three diferent alluvial soils in the central zone of Chile. Soils were two Inceptisols of the Casablanca Valley (Valparaíso Region, the first one without soil structure and with a densification zone in depth (S1 and the second one with sandy textural class (S3. A third soil was a Mollisol (S2 more structured than the others, situated on a locality of Melipilla (Metropolitan Region. The soils were characterized physically and morphologically and nematode genera were identified and counted using a dissecting microscope. ‘Chardonnay’ presented the highest population of Meloidogyne spp. on the three soil conditions but only significant in S2 soil. The population of Xiphinema spp. and Mesocriconema xenoplax were not representative enough to relate them with either soil or the different rootstocks. The amount of Meloidogyne spp. was inversely related with the sand content but positively related with the more structured soil. The stepwise regressions resulted useful when relating nematode populations with multiple soil factors.El ciclo de vida de los nematodos fitoparásitos ocurre en la rizósfera, por lo tanto, sus dinámicas de alimentación, parasitismo y movilidad están inevitablemente influenciadas por la interacción suelo-raíz. Se llevó a cabo un estudio para evaluar la respuesta de diferentes portainjertos de Vitis frente a algunas poblaciones de nematodos fitoparásitos en diferentes tipos de suelos. Se determinaron las poblaciones de nematodos fitopar

  2. Indian populations

    CERN Document Server

    Spahni,J

    1974-01-01

    Le Prof. J.C. Spahni qui a parcouru les Andes, Vénezuela etc. parle de ses expériences et connaissances qu'il a vécu au cours des 14 ans parmi les populations indiennes de la Cordillière des Andes. Il a ramené des objets artisanals indiens lesquels l'auditoire peut acquérir. L'introduction-conférence est suivi d'un film, commenté par lui-même; après l'entracte il y un débat-dialogue avec le public.

  3. Potential of tissue culture for breeding root-knot nematode resistance into vegetables.

    Science.gov (United States)

    Fassuliotis, G; Bhatt, D P

    1982-01-01

    Plant protoplast technology is being investigated as a means of transferring root-knot nematode resistance factors from Solanum sisymbriifolium into the susceptible S. melongena. Solanum sisymbriifolium plants regenerated from callus lost resistance to Meloidogyne javanica but retained resistance to M. incognita. Tomato plants cloned from leaf discs of the root-knot nematode resistant 'Patriot' were completely susceptible to M. incognita, while sections of stems and leaves rooted in sand in the absence of growth hormones retained resistance. Changes in resistance persisted for three generations. It is postulated that the exogenous hormonal constituents of the culture medium are modifying the expression of genetic resistance.

  4. Population Genetics with Fluctuating Population Sizes

    CERN Document Server

    Chotibut, Thiparat

    2016-01-01

    Standard neutral population genetics theory with a strictly fixed population size has important limitations. An alternative model that allows independently fluctuating population sizes and reproduces the standard neutral evolution is reviewed. We then study a situation such that the competing species are neutral at the equilibrium population size but population size fluctuations nevertheless favor fixation of one species over the other. In this case, a separation of timescales emerges naturally and allows adiabatic elimination of a fast population size variable to deduce the fluctuations-induced selection dynamics near the equilibrium population size. The results highlight the incompleteness of the standard population genetics with a strictly fixed population size.

  5. Dicty_cDB: SHF745 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available culus BAC clone RP23-292J21 from chromosome 6, complete sequence. 38 2.1 2 AW871630 |AW871630.1 ra80c01.y1 Bird...E PHOSPHODIESTERASE ;, mRNA sequence. 44 4.7 1 AW871214 |AW871214.1 ra56d01.y1 Bird-Rao Meloidogyne incognit... PHOSPHODIESTERASE ;, mRNA sequence. 44 4.7 1 AW829376 |AW829376.1 ra39d01.y1 Bird-Rao Meloidogyne incognita

  6. Perilous terra incognita--open-access journals.

    Science.gov (United States)

    Balon, Richard

    2014-04-01

    The author focuses on a new rapidly spreading practice of publication in open-access journals. The pros and cons of open-access journals are discussed. Publishing in these journals may be cost prohibitive for educators and junior faculty members. Some authors may be lured by the ease of publishing in open-access journals (and their, at times, inflated self-description, e.g., "international", "scientific"), and their possibly valuable contributions will escape the attention of Academic Psychiatry readership in the vast sea of open-access journals. The readership may be flooded with a large number of low-quality articles (maybe not even properly peer-reviewed) from open-access journals. It may take some time to sort out what is and what is not relevant and useful. Open-access publishing represents a problematic and controversial practice and may be associated with a conflict of interest for the editors and publishers of these journals.

  7. Control of Nematode Disease of Eggplant (Solanum aethiopicum L. Using Manure

    Directory of Open Access Journals (Sweden)

    Stephen Adekunle Abolusoro

    2014-01-01

    Full Text Available Pot experiment was conducted in the year 2010 and repeated in 2011 to examine the effects of organic manure (poultry, cow dung, domestic waste and inorganic manure (NPK 15:15:15 on the yield, soil and root population of Meloidogyne incognita that infected Ethiopian eggplant Solanum aethiopicum in a greenhouse at Kabba College of Agriculture, Ahmadu Bello University, Kabba, Nigeria. Each of the organic manure was applied as soil amendment at the rate of 5 t/ha and the inorganic fertilizer (NPK was applied at the rate of 200 kg/ha while there was an untreated control that acted as standard check. The experimental design was a completely randomized design comprising of five treatments including control and each of the treatments was replicated four times. The results of the experiment showed that all the organic manures considered and NPK fertilizer were effective in suppressing nematode negative effects on the plant as manifested in improved yield, reduced soil and root population as well as in reduced gall index of the organic and inorganic manure treated plants compared with the control. The mean fruit yield of the manure treated plant was 18+1, of NPK fertilizer treated ones was 17, while the average fruit number in untreated control was 6.5. The organic and inorganic manures treated plants had bigger fruit size compared with control and were significantly different from the control. The soil and root population as well as root gall index were reduced in all the manure treatments compared with the control and they were significantly different from the control. The results of this experiment confirmed that organic manure can be utilized to manage root-knot nematode (M. incognita in soil.

  8. Dicty_cDB: VHB169 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 24b.b1 Meloidogyne incognita BAC end sequence library (MIAAGSS 001) Meloidogyne incognita genomic, genomic survey...n-Sampling_GS-32-01-01-1P3-1P6KB marine metagenome genomic clone 1061005908980 5', genomic survey sequence. ...nomic clone 1061005828789 5', genomic survey sequence. 44 1.9 1 EJ316604 |EJ316604.1 1095403296369 Global-Oc...ean-Sampling_GS-27-01-01-1P8-2P0KB marine metagenome genomic clone 1061005525615 5', genomic survey...P3-1P6KB marine metagenome genomic clone 1061005648488 5', genomic survey sequence. 44 1.9 1 DH262164 |DH262

  9. 粗皮侧耳对花生根结线虫群体动态的影响及防治效果%Effect of Pleurotus ostreatus on Dynamics of Meloidogyne arenaria Population and Control Effectiveness

    Institute of Scientific and Technical Information of China (English)

    向红琼; 冯志新

    2001-01-01

    通过盆栽试验研究了杀线虫担子菌-粗皮侧耳(Pleurotus ostreatus)对花生根结线虫病的防治作用及施用技术.结果表明,P.ostreatus能有效地降低土壤中二龄幼虫的密度,与对照相比二龄幼虫减少80%以上;显著地降低花生根结线虫的侵染量,使根结内虫口密度下降40.00%~82.64%,根结减少86.96%~94.03%;推迟根结线虫的初侵染,有效地降低病害流行速度,使花生根结从对照组的逻辑斯蒂增长下降为施菌组的线性增长,有效地防治了花生根结线虫病,防效可达80%左右;同时其在土壤中易于定殖并具有较好的持效性.该菌防效与菌量及施菌时间关系密切,在菌量一定的情况下,施菌时间是影响防效的关键因素,以施菌后20d播种为宜.

  10. Nematóides que parasitam a soja na região de Bauru Nematode parasites of soybean in the Bauru region

    Directory of Open Access Journals (Sweden)

    Luiz Gonzaga E. Lordello

    1956-01-01

    Full Text Available Entre os sérios fatôres que atuam contra a expansão da cultura da soja no Estado de São Paulo, acha-se o representado por nematóides parasitos. Dêstes, os que mais têm atraído a atenção dos cultivadores e fitopatologistas são as espécies formadoras de galhas no sistema radicular (Meloidogyne spp.. O estudo do material atacado coligido em Bauru revelou que, naquela região, três formas se acham envolvidas, a saber : Pratylenchus sp., Meloidogyne incognita (Kofoid & White, 1919 Chitwood, 1949 e M. javanica bauruensis n. subsp. Neste trabalho é estudada a nova subespécie, sendo também apresentadas algumas observações sobre a população de M. incognita.One of the serious detriments to soybean (Glycine max (L. Merr. cultivation in the State of S. Paulo, Brazil, are root-parasitic nematodes. A study of infected material collected at Bauru, where at least two distinct soybean varieties were cultivated, disclosed that three forms were involved: a meadow nematode (Pralylenchus sp. and two root-knot nematodes (Meloidogyne incognita (Kofoid & White, 1919 Chitwood, 1949, and M. javanica bauruensis n. subsp.. Silva, Lordello & Miyasaka (3 published some observations about the resistance of several soybean varieties to the attacks by root-knot nematodes in Campinas. A detailed study of the nematodes involved in those experiments, which were considered as related do M. incognita, has not yet been made. One of the varieties tested, La 41-1219, proved to be resistant, thereby providing promising material for further studies and breeding. Unfortunately, such a variety when planted in Bauru, was severely attacked by a root-knot species, which is identified as M. incognita. Attacks by M. javanica bauruensis was not noted in that variety but was noted in another variety (Abura growing adjacent in the same field. The host preference of those two nematodes was specific and very marked. M. incognita attacked only var. La 41-1219 and M. javanica

  11. Nematicidal Constituents from the Essential Oil of Chenopodium Ambrosioides Aerial Parts

    OpenAIRE

    2011-01-01

    Essential oil of Chinese medicinal herb, Chenopodium ambrosioides aerial parts was found to possess nematicidal activity against the root-knot nematodes, Meloidogyne incognita. The essential oil of C. ambrosioides was obtained by hydrodistillation and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 27 components of the essential oil were identified. The principal compounds in C. ambrosioides essential oil were (Z)-ascaridole (27.27%), ρ-cymene (19.05%), isoascaridole (14....

  12. Efeitos de diferentes níveis de matéria orgânica no solo e de inóculo sobre a interação planta-Meloidogyne spp. e a produção massal de Pasteuria penetrans Effects of cow manure levels in the soil and inoculum concentration on the plant-Meloidogyne spp. interaction and on the mass production of Pasteuria penetrans

    Directory of Open Access Journals (Sweden)

    Fábio Ramos Alves

    2007-12-01

    Full Text Available Foram estudados os efeitos de quatro proporções de esterco de curral no solo, 0, 20, 33 e 50% (V:V, e três níveis de inóculo de Meloidogyne spp. (3.000, 6.000 e 9.000 J2 por planta na concentração de fenóis em raízes de tomateiro, no desenvolvimento das fêmeas, nas células gigantes induzidas por esses patógenos e na infecção e reprodução de Pasteuria penetrans. O experimento foi conduzido em casa-de-vegetação, em delineamento inteiramente ao acaso com doze repetições, sendo avaliado 50 dias após a inoculação das plantas. O tamanho médio das fêmeas do nematóide foi maior quando as plantas foram inoculadas com 3.000 J2. Maior percentual de fêmeas infectadas por P. penetrans foi observado quando não se utilizou esterco no substrato ou quando as plantas foram inoculadas com 3.000 J2. As plantas inoculadas com 9.000 J2 e cultivadas no substrato com 20% de esterco foram as que produziram mais endósporos. A concentração de fenóis nas raízes aumentou à medida que se acrescentou esterco de curral ao substrato. As células gigantes de plantas cultivadas no substrato com 33 e 50% de esterco apresentaram menores número, tamanho e quantidade de núcleos. O aumento da proporção de esterco de curral ao substrato causou aumento nas concentrações de fenóis nas raízes, fato que foi deletério às células gigantes, prejudicial ao desenvolvimento do nematóide e à reprodução de P. penetrans.The effects of four different proportions of cow manure, 0, 20, 33 and 50% (V:V and three Meloidogyne spp. inoculum levels (3,000; 6,000 and 9,000 J2 per plant on the phenol concentration in the tomato roots, in the nematode female development, the giant cells induced by the nematode and on the reproduction of Pasteuria penetrans were investigated. The experiment was carried out in greenhouse, in a completely randomized design with twelve replicates, and evaluated 50 days after inoculation. The size of nematode females was higher when

  13. Effective population size of korean populations.

    Science.gov (United States)

    Park, Leeyoung

    2014-12-01

    Recently, new methods have been developed for estimating the current and recent changes in effective population sizes. Based on the methods, the effective population sizes of Korean populations were estimated using data from the Korean Association Resource (KARE) project. The overall changes in the population sizes of the total populations were similar to CHB (Han Chinese in Beijing, China) and JPT (Japanese in Tokyo, Japan) of the HapMap project. There were no differences in past changes in population sizes with a comparison between an urban area and a rural area. Age-dependent current and recent effective population sizes represent the modern history of Korean populations, including the effects of World War II, the Korean War, and urbanization. The oldest age group showed that the population growth of Koreans had already been substantial at least since the end of the 19th century.

  14. Effects of potato-cotton cropping systems and nematicides on plant-parasitic nematodes and crop yields.

    Science.gov (United States)

    Crow, W T; Weingartner, D P; Dickson, D W

    2000-09-01

    Belonolaimus longicaudatus has been reported as damaging both potato (Solanum tuberosum) and cotton (Gossypium hirsutum). These crops are not normally grown in cropping systems together in areas where the soil is infested with B. longicaudatus. During the 1990s cotton was grown in a potato production region that was a suitable habitat for B. longicaudatus. It was not known how integrating the production of these two crops by rotation or double-cropping would affect the population densities of B. longicaudatus, other plant-parasitic nematodes common in the region, or crop yields. A 3-year field study evaluated the viability of both crops in monocropping, rotation, and double-cropping systems. Viability was evaluated using effects on population densities of plant-parasitic nematodes and yields. Rotation of cotton with potato was found to decrease population densities of B. longicaudatus and Meloidogyne incognita in comparison with continuous potato. Population densities of B. longicaudatus following double-cropping were greater than following continuous cotton. Yields of both potato and cotton in rotation were equivalent to either crop in monocropping. Yields of both crops were lower following double-cropping when nematicides were not used.

  15. INFLUENCE OF ROOTSTOCKS ON Fusarium WILT, NEMATODE INFESTATION, YIELD AND FRUIT QUALITY IN WATERMELON PRODUCTION

    Directory of Open Access Journals (Sweden)

    Juan Carlos Álvarez-Hernández

    2015-08-01

    Full Text Available Cucurbita maxima x Cucurbita moschata rootstock are used to prevent infection with Fusarium oxysporum f. sp. niveum in watermelon production; however, this rootstock is not effective against nematode attack. Because of their vigor, the grafted plants can be planted at lower plant densities than the non-grafted plants. The tolerance to Fusarium oxysporum f. sp. niveum and Meloidogyne incognita was assessed in watermelon plants grafted onto a hybrid of Citrullus lanatus cv Robusta or the Cucurbita maxima x Cucurbita moschata cv Super Shintoza rootstocks. The densities of plants were 2083 and 4166 plants ha-1. Non-grafted watermelons were the controls. The Crunchy Red and Sangría watermelon cultivars were used as the scions, it the latter as a pollinator. The experiments were performed for two production cycles in soils infested with Fusarium oxysporum f. sp. niveum and Meloidogyne incognita. The incidence of Fusarium oxysporum f. sp. niveum was significantly greater in the non-grafted than in the grafted plants. The grafted plants presented similar resistance to Fusarium regardless of the rootstock. The root-knot galling index for Meloidogyne incognita was significantly lower in plants grafted onto Citrullus lanatus cv Robusta than onto the other rootstock. The yields of plants grafted onto Citrullus lanatus cv Robusta grown at both plant densities were significantly higher than in the other treatments.

  16. Aliphatic ketones from Ruta chalepensis (Rutaceae) induce paralysis on root knot nematodes.

    Science.gov (United States)

    Ntalli, Nikoletta G; Manconi, Francesca; Leonti, Marco; Maxia, Andrea; Caboni, Pierluigi

    2011-07-13

    This paper reports on the use of Ruta chalepensis L. extracts as a potential nematicide against root knot nematodes Meloidogyne incognita and Meloidogyne javanica . The essential oil (REO) and methanol extract (RME) of R. chalepensis were tested against second-stage juveniles, with REO inducing paralysis in both species (EC(50/1d) = 77.5 and 107.3 mg/L) and RME being selective for M. incognita (EC(50/1d) = 1001 mg/L). Chemical characterization of extracts was done by means of GC-MS and LC-MS, revealing mainly aliphatic ketones and coumarins, respectively. The first-ranking volatile nematicidal component in terms of individual activity against both species was 2-undecanone (EC(50) = 20.6 and 22.5 mg/L for M. incognita and M. javanica, respectively). This fact together with its high concentration in the most active extract found in this study, namely, REO (2926 mg/kg), categorizes 2-undecanone among the nematicidal principles of R. chalepensis. On the contrary, coumarins rutin and 8-methoxypsoralen were not found to be nematicidal at concentrations of ≤500 mg/L. Interestingly, M. incognita was found more sensitive than M. javanica.

  17. Education Vital Signs: Population.

    Science.gov (United States)

    Zakariya, Sally Banks

    1985-01-01

    Population changes and demographics shape the future of public schools. Includes statistics on ethnic makeup of student population, the projected baby boomlet, children of working mothers, households without children, and the aging population. (MD)

  18. Solarização do solo e biofumigação no cultivo protegido de tomate The effect of solarization and biofumigation on tomatoes under protected cultivation

    Directory of Open Access Journals (Sweden)

    Mírian Josefina Baptista

    2006-03-01

    Full Text Available Foi avaliado o efeito da fumigação com brometo de metila, biofumigação e da solarização sobre a população do fitonematóide Meloidogyne sp., a incidência de plantas daninhas e características químicas do solo em ambiente protegido para o plantio de tomate. Foram testados os tratamentos: resíduos de couve-flor e de brócolos (2% v/v, cama de aves (2% v/v, fumigação com brometo de metila e solo não tratado, todos com e sem solarização. O período de solarização foi de dois meses e, em seguida, foi feito o plantio dos híbridos de tomate Alambra, resistente a Meloidogyne incognita (gene Mi, e Duradoro (suscetível. O banco de sementes de plantas daninhas no solo foi avaliado em amostras retiradas do perfil de 0 a 20 cm de profundidade, com amostragem das plantas daninhas emergidas aos 30 dias após o transplante do tomate. Para as análises químicas foram retiradas amostras de solo após a solarização e biofumigação. A solarização do solo, uso de cama de aves e fumigação com brometo de metila reduziram a população de nematóides no solo e o número de massas de ovos nas raízes dos dois híbridos avaliados. O híbrido Alambra, no entanto, apresentou massa seca e fresca da parte aérea, altura e peso de frutos, na primeira colheita, maiores nos solos solarizados, respondendo melhor à solarização que o 'Duradoro'. A fumigação com brometo de metila e a solarização reduziram a viabilidade das sementes e a sobrevivência de plantas daninhas. A solarização aumentou os teores de fósforo e de cobre e reduziu os teores de zinco no solo.A greenhouse experiment was carried out to test the effects of solarization and biofumigation on the population of the plant parasitic nematode Meloidogyne sp., on the incidence of weeds and on soil chemical properties in protected areas for the cultivation of tomatoes. Brassica residues (broccoli and cauliflower and chicken litter amendments (2% v/v, methyl bromide and no amendment

  19. Human Population Problems

    Science.gov (United States)

    Emmel, Thomas C.; Sligh, Michael M.

    1970-01-01

    Asserts that overpopulation is the most pressing world problem. Topics discussed include population control in primitive societies, population growth and control in modern societies, methods of motivational population control, consequences of no population control, and mass famines during the 1970's in underdeveloped countries. Cities 33…

  20. Understanding Rural Population Loss.

    Science.gov (United States)

    McGranahan, David A.; Beale, Calvin L.

    2002-01-01

    A quarter of nonmetro counties lost population in the 1990s, but population loss was not related to poverty rate or low educational levels, perhaps because low-skill workers can no longer expect better wages in urban areas. Population loss was related to low population density and remoteness (which decrease access to services), lack of natural…

  1. Why Population in 1974?

    Science.gov (United States)

    O'Connor, Marion

    1974-01-01

    Discusses the impact of world population growth leading to the establishment of the United Nations Fund for Population Activities and to the declaration of 1974 as World Population Year. Previews some of the parameters and interconnecting interests to be considered during this year of intensive population study. (JR)

  2. 低钾逆境下根结线虫感染所诱导的番茄根巨型细胞的组织病理学反应%Histopathological Response of Giant Cell Induced by Root-knot Nematode, Meloidogyne javanica, in Tomato Roots under Potassium Stress

    Institute of Scientific and Technical Information of China (English)

    袁林; 方文珍; 罗大民

    2008-01-01

    Comparison of histopathological response and quantitative measurement of giant cell(GC)induced by Meloidogyne javanica in tomato root were studied under potassium-deficient(0.2 mmol/L K+)and replete conditions(control,6.0 mmol/L K+).K+-deficient stress did not impede the formation and maintenance of GC.The mean number of GC per feeding site as well as the meall diameter of GC did not differ between the treatments.However,the thickness of cell wall including components resulted from the accumulated polysaccharide and the length of cell-wall ingrowth increased 5-25 d after inoculation in K+-deficient as compared with K+-replete conditions.An increase of cell-wall ingrowth suggested a kind of compensational response to the potassium stress.

  3. Tomato transgenic plants expressing hairpin construct of a nematode protease gene conferred enhanced resistance to root-knot nematodes

    Science.gov (United States)

    Dutta, Tushar K.; Papolu, Pradeep K.; Banakar, Prakash; Choudhary, Divya; Sirohi, Anil; Rao, Uma

    2015-01-01

    Root-knot nematodes (Meloidogyne incognita) cause substantial yield losses in vegetables worldwide, and are difficult to manage. Continuous withdrawal of environmentally-harmful nematicides from the global market warrants the need for novel nematode management strategies. Utility of host-delivered RNAi has been demonstrated in several plants (Arabidopsis, tobacco, and soybean) that exhibited resistance against root-knot and cyst nematodes. Herein, a M. incognita-specific protease gene, cathepsin L cysteine proteinase (Mi-cpl-1), was targeted to generate tomato transgenic lines to evaluate the genetically modified nematode resistance. In vitro knockdown of Mi-cpl-1 gene led to the reduced attraction and penetration of M. incognita in tomato, suggesting the involvement of Mi-cpl-1 in nematode parasitism. Transgenic expression of the RNAi construct of Mi-cpl-1 gene resulted in 60–80% reduction in infection and multiplication of M. incognita in tomato. Evidence for in vitro and in vivo silencing of Mi-cpl-1 was confirmed by expression analysis using quantitative PCR. Our study demonstrates that Mi-cpl-1 plays crucial role during plant-nematode interaction and plant-mediated downregulation of this gene elicits detrimental effect on M. incognita development, reinforcing the potential of RNAi technology for management of phytonematodes in crop plants. PMID:25883594

  4. Tomato transgenic plants expressing hairpin construct of a nematode protease gene conferred enhanced resistance to root-knot nematodes

    Directory of Open Access Journals (Sweden)

    Tushar Kanti Dutta

    2015-04-01

    Full Text Available Root-knot nematodes (Meloidogyne incognita cause substantial yield losses in vegetables worldwide, and are difficult to manage. Continuous withdrawal of environmentally-harmful nematicides from the global market warrants the need for novel nematode management strategies. Utility of host-delivered RNAi has been demonstrated in several plants (Arabidopsis, tobacco and soybean that exhibited resistance against root-knot and cyst nematodes. Herein, a M. incognita-specific protease gene, cathepsin L cysteine proteinase (Mi-cpl-1, was targeted to generate tomato transgenic lines to evaluate the genetically modified nematode resistance. In vitro knockdown of Mi-cpl-1 gene led to the reduced attraction and penetration of M. incognita in tomato, suggesting the involvement of Mi-cpl-1 in nematode parasitism. Transgenic expression of the RNAi construct of Mi-cpl-1 gene resulted in 60-80% reduction in infection and multiplication of M. incognita in tomato. Evidence for in vitro and in vivo silencing of Mi-cpl-1 was confirmed by expression analysis using quantitative PCR. Our study demonstrates that Mi-cpl-1 plays crucial role during plant-nematode interaction and plant-mediated downregulation of this gene elicits detrimental effect on M. incognita development, reinforcing the potential of RNAi technology for management of phytonematodes in crop plants.

  5. The Growing Human Population.

    Science.gov (United States)

    Keyfitz, Nathan

    1989-01-01

    Discusses the issue of human population. Illustrates the projections of the growing human population in terms of developed and less developed countries. Describes the family planning programs in several countries. Lists three references for further reading. (YP)

  6. Glaucoma in Asian Populations

    Science.gov (United States)

    ... Us Donate In This Section Glaucoma In Asian Populations email Send this article to a friend by ... an even more serious problem as the world population and longevity increases. The other major glaucoma type ...

  7. Multiple Population Theory: Extreme helium population problem

    OpenAIRE

    Yi, Sukyoung K.

    2009-01-01

    The spreads in chemical abundances inferred by recent precision observations suggest that some or possibly all globular clusters can no longer be considered as simple stellar populations. The most striking case is omega Cen in the sense that its bluest main-sequence despite its high metallicity demands an extreme helium abundance of Y > 0.4. I focus on this issue of "the extreme helium population problem" in this review.

  8. Population control charts for population data.

    Science.gov (United States)

    Hansen, John P

    2007-01-01

    Healthcare managers are beginning to collect full population data, rather than sample data, on some patient and performance measures. For example, hospitals and healthcare systems already gather and store comprehensive data on admissions, ambulatory encounters, and other procedures. And as the electronic medical record is more widely used, complete population data will be collected on an even wider range of clinical measures, such as blood pressure and Laboratory values, in both inpatient and outpatient settings. To correctly monitor process quality when working with full population data, rather than sample data, healthcare managers will need appropriate statistical tools. Traditional control charts, which are used for tracking processes over time, are not suitable for such population data because they are based on the assumption that sample data are being collected. The author proposes a new type of control chart specifically for use with such population data: population control charts. These control charts can be used for monitoring processes that have output measures with continuous, binomial, or nonbinomial rate variables.

  9. Controlling Population with Pollution

    Science.gov (United States)

    Browne, Joseph

    2010-01-01

    Population models are often discussed in algebra, calculus, and differential equations courses. In this article we will use the human population of the world as our application. After quick looks at two common models we'll investigate more deeply a model which incorporates the negative effect that accumulated pollution may have on population.

  10. Modeling Exponential Population Growth

    Science.gov (United States)

    McCormick, Bonnie

    2009-01-01

    The concept of population growth patterns is a key component of understanding evolution by natural selection and population dynamics in ecosystems. The National Science Education Standards (NSES) include standards related to population growth in sections on biological evolution, interdependence of organisms, and science in personal and social…

  11. Impact of castor meal on root-knot and free-living nematodes

    Directory of Open Access Journals (Sweden)

    Cecilia Helena Silvino Prata Ritzinger

    2014-08-01

    Full Text Available Soil amendment may enhance soil quality as well as reduce plant-parasitic nematode. Despite the many applications already undertaken using castor meal, its efficiency in controlling root-knot nematodes (RKN, Meloidogyne incognita when applied to melon (Cucumis melo is still not clear. Three different amounts of castor meal (Ricinus communis applied were evaluated in microplots planted with melon either with or without RKN. The impact of castor meal on soil free-living nematode communities was also determined. Total nematode genera richness was estimated as 37 for the entire set of microplots sampled across both sampling dates. Rarefaction analysis resulted in 12 collector's curves out of the total of 30 that reached the horizontal asymptote. Univariate ANOVA with two factors yielded differences (p < 0.05 only with regard to the time factor. Simpson, Shannon, Evenness and Equitability indices showed a trend toward moderate increases by the end of the experiment, while the other indices were higher for tomato in pre-transplant sampling compared to harvest. Nematode community and diversity changed during the course of the experiment, although there was substantial confounding heterogeneity within and between the factorial combinations from the beginning. Root knot population was not reduced by the castor meal but increased throughout the period, regardless of treatment. RKN reduced melon yield, number and weight of melon.

  12. Tropical rotation crops influence nematode densities and vegetable yields.

    Science.gov (United States)

    McSorley, R; Dickson, D W; de Brito, J A; Hochmuth, R C

    1994-09-01

    The effects of eight summer rotation crops on nematode densities and yields of subsequent spring vegetable crops were determined in field studies conducted in north Florida from 1991 to 1993. The crop sequence was as follows: (i) rotation crops during summer 1991; (ii) cover crop of rye (Secale cereale) during winter 1991-92; (iii) 'Lemondrop L' squash (Cucurbita pepo) during spring 1992; (iv) rotation crops during summer 1992; (v) rye during winter 1992-93; (vi) 'Classic' eggplant (Solanum melongena) during spring 1993. The eight summer crop rotation treatments were as follows: 'Hale' castor (Ricinus communis), velvetbean (Mucuna deeringiana), sesame (Sesamum indicum), American jointvetch (Aeschynomene americana), weed fallow, 'SX- 17' sorghum-sudangrass (Sorghum bicolor x S. sudanense), 'Kirby' soybean (Glycine max), and 'Clemson Spineless' okra (Hibiscus esculentus) as a control. Rotations with castor, velvetbean, American jointvetch, and sorghum-sudangrass were most effective in maintaining the lowest population densities of Meloidogyne spp. (a mixture of M. incognita race 1 and M. arenaria race 1), but Paratrichodorus minor built up in the sorghum-sudangrass rotation. Yield of squash was lower (P crops evaluated here may be useful for managing nematodes in the field and for improving yields of subsequent vegetable crops.

  13. Molecular Population Genetics

    Science.gov (United States)

    Casillas, Sònia; Barbadilla, Antonio

    2017-01-01

    Molecular population genetics aims to explain genetic variation and molecular evolution from population genetics principles. The field was born 50 years ago with the first measures of genetic variation in allozyme loci, continued with the nucleotide sequencing era, and is currently in the era of population genomics. During this period, molecular population genetics has been revolutionized by progress in data acquisition and theoretical developments. The conceptual elegance of the neutral theory of molecular evolution or the footprint carved by natural selection on the patterns of genetic variation are two examples of the vast number of inspiring findings of population genetics research. Since the inception of the field, Drosophila has been the prominent model species: molecular variation in populations was first described in Drosophila and most of the population genetics hypotheses were tested in Drosophila species. In this review, we describe the main concepts, methods, and landmarks of molecular population genetics, using the Drosophila model as a reference. We describe the different genetic data sets made available by advances in molecular technologies, and the theoretical developments fostered by these data. Finally, we review the results and new insights provided by the population genomics approach, and conclude by enumerating challenges and new lines of inquiry posed by increasingly large population scale sequence data. PMID:28270526

  14. Population education country programmes.

    Science.gov (United States)

    1980-12-01

    Population education country programs in the countries of India, Malaysia, Nepal, the Philippines, and Sri Lanka are reviewed. In India the machinery is beginning to roll for the nationwide implementation of a 3-year national population education project. A variety of strategies will be used at the national and state levels using existing facilities and infrastructure for implementing various aspects of the program. Recommendations and proposed project activities arrived at during 2 workshop/training programs are outlined. The Malaysian population education program recently developed a working draft of the scope, content, and objectives of population education at the primary and lower and upper secondary levels. This working draft is being pretested among teachers and curriculum developers, and, once revised, it will serve as the overall guiding framework for those responsible for preparing curriculum and instructional materials on population education. The population education program in Nepal will be implemented by 3 units: Curriculum, Textbook, Supervision, and Development Center; Tribhuvan University; and Division of Adult Education. The longterm objective is to institutionalize population education in the formal and nonformal education programs including the university. The Population Education Program of the Philippines has prepared a reader in Filipino for grade 3 pupils. Population education in the country has been promoted to a lesser degree in private than in public schools. the Institutional Development Program of the Population Center Foundation conducted a Summer Institute in Instructional Product Development for the primary purpose of institutionalizing population in the social science curriculum at the tertiary level. The population education program of Sri Lanka will undergo a revival in the recently approved 2-year project agreement between Sri Lanka's government and the United Nations Fund for Population Activities.

  15. Befolkningsudviklingen (Population Development)

    DEFF Research Database (Denmark)

    Nørgaard, Jørgen

    2010-01-01

    The article takes the 1972 report, The Limits to Growth as its starting point, briefly explaining the Systam Dynamics model used for the report's analyses. Focus is on the important role of population. The simple model of I = PxAxT, where I is the environmental Impact, P population, A is the Affl......The article takes the 1972 report, The Limits to Growth as its starting point, briefly explaining the Systam Dynamics model used for the report's analyses. Focus is on the important role of population. The simple model of I = PxAxT, where I is the environmental Impact, P population...

  16. Measurably evolving populations

    DEFF Research Database (Denmark)

    Drummond, Alexei James; Pybus, Oliver George; Rambaut, Andrew

    2003-01-01

    processes through time. Populations for which such studies are possible � measurably evolving populations (MEPs) � are characterized by sufficiently long or numerous sampled sequences and a fast mutation rate relative to the available range of sequence sampling times. The impact of sequences sampled through...... time has been most apparent in the disciplines of RNA viral evolution and ancient DNA, where they enable us to estimate divergence times without paleontological calibrations, and to analyze temporal changes in population size, population structure and substitution rates. Thus, MEPs could increase our...

  17. Axenizing and Culturing Endomigratory Plant-Parasitic Nematodes using Pluronic F127, Including its Effects, on Population Dynamics of Pratylenchus penetrans.

    Science.gov (United States)

    Ko, M P; Schmitt, D P; Sipes, B S

    1996-03-01

    A non-chemical technique for surface sterilizing plant-parasitic nematodes for aseptic cultures is described. The method is most applicable to nematodes with active migratory infective stages and requires only a few starting specimens. Rate of achieving a primary aseptic culture with the technique ranged from 60%-100% depending on the conditions of the specimens collected for culturing. Aseptic cultures of species of Meloidogyne, Rotylenchuluz, Pratylenchus, and Radopholus initiated with the method remained contamination-free after 12 months of maintenance in tomato root explant or alfalfa callus cultures. Further studies of Pluronic F127, a polyol gel medium employed in the technique to confine the spread of contaminating bacteria or fungi associated with the nematodes, showed that the polyol gel was a suitable support medium for culturing corn root explant, alfalfa callus tissues, and consequently Pratylenchus species including P. agilis, P. brachyurus, P. scribneri, and P. penetrans. During the course of 10 months, P. penetrans reared in polyol-base medium followed a standard biological growth curve, multiplied to a higher population density, maintained a similar female-to-male ratio, and possessed a similar tendency to reside inside or outside host tissues as did P. penetrans reared in agar-base medium. The percentages of P. penetrans juveniles in the sub-populations residing outside or inside the host tissues reared in polyol-base medium also were similar to and fluctuated temporally in like manner as those reared in agar-base medium. Members of these sub-populations from the polyol- or agar-base were equally infective and reproductive after 9 months of culturing.

  18. Population Education Regional News.

    Science.gov (United States)

    Population Education in Asia and the Pacific Newsletter, 1985

    1985-01-01

    Discusses: (1) a comparative study on managing population education programs; (2) a South Pacific workshop in which training materials on sex education, family life education, and nutrition-oriented mixed gardening were developed; and (3) a workshop on evaluative research, the focus of national population education programs in Asia. (JN)

  19. Population Education Country Programmes.

    Science.gov (United States)

    Population Education in Asia and the Pacific Newsletter, 1983

    1983-01-01

    Highlights various population education programs in Afghanistan, China, India, Malaysia, Sri Lanka, and Vietnam. Also describes population education programs at primary and secondary levels in Thailand, curriculum and instructional materials development in this country, and teaching units and curriculum outlines developed from a workshop for…

  20. Understanding Population Projections.

    Science.gov (United States)

    Haub, Carl

    1987-01-01

    Population projections are "what if" computational exercises. Given selected assumptions about future trends in fertility, mortality, and migration, population trends can be projected. Government and business planners need this information, and they also require enough time to put facilities in place to meet future needs. Everyone benefits from a…

  1. The Population Activist's Handbook.

    Science.gov (United States)

    Population Inst., Washington, DC.

    This handbook is a guide to effective action strategies on dealing with overpopulation. Divided into five sections, the book outlines programs, suggests references, and lists resources that are helpful for thinking and for planning action on population issues. Section one focuses on strategies to change the current population policy choices made…

  2. Dimensions of Philippine population.

    Science.gov (United States)

    1980-01-01

    Major findings of a 2 1/2 year research program on Philippine population are presented. The population situation is described with respect to fertility, mortality, life expectancy, migration, labor force, and family formation. Policy recommendations addressing problems in each of these areas are made.

  3. Negative Drift in Populations

    DEFF Research Database (Denmark)

    Lehre, Per Kristian

    2011-01-01

    An important step in gaining a better understanding of the stochastic dynamics of evolving populations, is the development of appropriate analytical tools. We present a new drift theorem for populations that allows properties of their long-term behaviour, e.g. the runtime of evolutionary algorithms...

  4. POPULATION TURNING POINT

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    Latest census shows structural imbalance of population has replaced explosive growth to become China’s top challenge China’s population grew by less than 1 percent annually in the last decade,but it still remains the world’s largest at 1.37 billion people,according to results

  5. Ecology and Population

    Science.gov (United States)

    Hawley, Amos H.

    1973-01-01

    Author suggests that study of population growth is not a field of study only for ecologists. Population growth is related with social sciences in the nature of its process and future consequences. Broader, comprehensive approaches to this problem will be useful. (PS)

  6. Cairo: repackaging population control.

    Science.gov (United States)

    Simons, H

    1995-01-01

    Aid agencies, charities, and other nongovernmental organizations once denounced population control programs as racist interference in the third world. Yet, at the United Nations Conference on Population and Development in Cairo last September, these same organizations endorsed very similar ideas. The U.N. can now claim that even its fiercest critics not only have muted their criticism of population control programs but now positively endorse them. Over the last 30 years, population control has been consciously repackaged by the U.S. establishment. The image of population control has changed from being overtly anti-third world to being about giving the people of the third world--especially women--basic rights in family planning. Wrapped up in the language of women's empowerment and environmentalism, the establishment's old arguments about there being too many nonwhite babies in the world, have, unfortunately, won the day.

  7. Diversity of Poissonian populations

    Science.gov (United States)

    Eliazar, Iddo I.; Sokolov, Igor M.

    2010-01-01

    Populations represented by collections of points scattered randomly on the real line are ubiquitous in science and engineering. The statistical modeling of such populations leads naturally to Poissonian populations—Poisson processes on the real line with a distinguished maximal point. Poissonian populations are infinite objects underlying key issues in statistical physics, probability theory, and random fractals. Due to their infiniteness, measuring the diversity of Poissonian populations depends on the lower-bound cut-off applied. This research characterizes the classes of Poissonian populations whose diversities are invariant with respect to the cut-off level applied and establishes an elemental connection between these classes and extreme-value theory. The measures of diversity considered are variance and dispersion, Simpson’s index and inverse participation ratio, Shannon’s entropy and Rényi’s entropy, and Gini’s index.

  8. Global population growth.

    Science.gov (United States)

    Langmore, J

    1992-07-01

    The global population passed 5 billion in 1987. In the year 2000 the world's population will be more than 6 billion, increasing by 90-100 million each year. About 95% of future demographic growth will take place in developing countries. The number of school age children is projected to increase from 940 million in 1980 to 1280 million by the year 2000. Under current labor force growth projections in developing countries, around 1.6 billion new jobs will have to be created between 1980 and 2025, with nearly 1 billion of them in Asia. Population often increases at a more rapid rate than agricultural growth. Food production per capita has declined in 70 developing countries. Much of the projected population increase will take place in environmentally fragile regions of the developing world. Population pressures contribute to deforestation, desertification, and scarcity of clean water. The United Nations Population Fund has estimated that in Asia over 43% of women not using family planning would like to postpone, space, or limit their childbearing. Over half of the world's couples of reproductive age are now using contraception. Family planning to postpone the first birth and to eliminate late child bearing would reduce both child loss and maternal illness and death. Both infant and maternal mortality are greater with higher order births. Reducing average family size is an effective way of reducing infant and maternal mortality. The World Bank has given high priority to population assistance, with large programs in Bangladesh, Egypt, India, Indonesia, the Philippines, and Thailand. Population assistance provided by the Australian International Development Assistance Bureau totaled about $4.5 million during 1989-90 and is expected to be about $8 million during 1991-92. Australia should increase the proportion of its development assistance budget devoted to population, and family planning programs should increase to around $26 million in line with other major donors.

  9. The population threat.

    Science.gov (United States)

    Teitelbaum, M S

    1992-01-01

    Commentary is provided on the challenges faced by the new Clinton administration in formulating US key foreign policy initiatives. There is an urgent need to provide balanced and effective foreign aid for reducing high fertility rates in the developing world. There is also a need to effectively monitor the large migrations of populations. Over the past 10 years, the US has not been actively practicing world leadership on population issues. 3 changes in 1993 give impetus to redirect foreign policy: 1) the waning influence of fringe groups who controlled population issues; 2) the campaign promises to restore UN population stabilization programs; and 3) the evidence from the Persian Gulf and Yugoslavia that demographic issues require planning and assessment. Global population growth has been concentrated in the past 40 years, in part due to mortality declines and sustained high fertility. Of significance is the rapidness and momentum of growth. A high percentage are and will be children. Urban population is also growing rapidly in high fertility countries. Countries with high fertility and significant rural-to-urban migration also have large international migrations. The evolution of policy since the 1950s, which for the most part ignored population issues, is discussed. The American debates have been charged with emotionalism: about human sexuality, legitimacy of voluntary fertility control, the role and status of women and men, abortion, intergenerational transfer of obligations, ethnic solidarity and the sovereignty of national borders, and the proper roles of the state versus the marketplace. There have been over 200 years of ideological argument over population issues. The Malthusian argument was that large population size did not increase prosperity, and growth should be limited. The Marxist-Leninist position was that contraception was Malthusian, abortion was a woman's right, and population growth was neutral. By late 1970 the Chinese Maoists adopted the moral

  10. [Trends in population aging].

    Science.gov (United States)

    Valkovics, E

    1990-11-01

    The age structure of the world population between 1950 and 1985 is analyzed according to changes in fertility, mortality, and international migration in developing and developed countries. "Relying on the results of the medium scenario of the population forecasts prepared by the U.N. Division of International Economic and Social Affairs, the author demonstrates that aging of the world population will become a global phenomenon, characteristic of every region and county of the world, between 1985 and 2025." (SUMMARY IN ENG AND RUS)

  11. Constructing populations in biobanking

    DEFF Research Database (Denmark)

    Tupasela, Aaro; Snell, Karoliina; Cañada, Jose a.

    2015-01-01

    This article poses the question of whether biobanking practices and standards are giving rise to the construction of populations from which various biobanking initiatives increasingly draw on for legitimacy? We argue that although recent biobanking policies encourage various forms of engagement...... to the construction of populations, whereby specific nationalities, communities, societies, patient groups and political systems become imbued or bio-objectified with particular characteristics, such as compliant, distant, positive, commercialized or authoritarian. This bio-objectification process is problematic...... in relation to policy aspirations ascribed to biobanking engagement since it gives rise to reified notions of different populations....

  12. Parallel grid population

    Science.gov (United States)

    Wald, Ingo; Ize, Santiago

    2015-07-28

    Parallel population of a grid with a plurality of objects using a plurality of processors. One example embodiment is a method for parallel population of a grid with a plurality of objects using a plurality of processors. The method includes a first act of dividing a grid into n distinct grid portions, where n is the number of processors available for populating the grid. The method also includes acts of dividing a plurality of objects into n distinct sets of objects, assigning a distinct set of objects to each processor such that each processor determines by which distinct grid portion(s) each object in its distinct set of objects is at least partially bounded, and assigning a distinct grid portion to each processor such that each processor populates its distinct grid portion with any objects that were previously determined to be at least partially bounded by its distinct grid portion.

  13. AMPHIBIAN POPULATION DYNAMICS

    Science.gov (United States)

    Agriculture has contributed to loss of vertebrate biodiversity in many regions, including the U.S. Corn Belt. Amphibian populations, in particular, have experienced widespread and often inexplicable declines, range reductions, and extinctions. However, few attempts have been made...

  14. Modeling Honey Bee Populations.

    Directory of Open Access Journals (Sweden)

    David J Torres

    Full Text Available Eusocial honey bee populations (Apis mellifera employ an age stratification organization of egg, larvae, pupae, hive bees and foraging bees. Understanding the recent decline in honey bee colonies hinges on understanding the factors that impact each of these different age castes. We first perform an analysis of steady state bee populations given mortality rates within each bee caste and find that the honey bee colony is highly susceptible to hive and pupae mortality rates. Subsequently, we study transient bee population dynamics by building upon the modeling foundation established by Schmickl and Crailsheim and Khoury et al. Our transient model based on differential equations accounts for the effects of pheromones in slowing the maturation of hive bees to foraging bees, the increased mortality of larvae in the absence of sufficient hive bees, and the effects of food scarcity. We also conduct sensitivity studies and show the effects of parameter variations on the colony population.

  15. Modeling Honey Bee Populations

    Science.gov (United States)

    Torres, David J.; Ricoy, Ulises M.; Roybal, Shanae

    2015-01-01

    Eusocial honey bee populations (Apis mellifera) employ an age stratification organization of egg, larvae, pupae, hive bees and foraging bees. Understanding the recent decline in honey bee colonies hinges on understanding the factors that impact each of these different age castes. We first perform an analysis of steady state bee populations given mortality rates within each bee caste and find that the honey bee colony is highly susceptible to hive and pupae mortality rates. Subsequently, we study transient bee population dynamics by building upon the modeling foundation established by Schmickl and Crailsheim and Khoury et al. Our transient model based on differential equations accounts for the effects of pheromones in slowing the maturation of hive bees to foraging bees, the increased mortality of larvae in the absence of sufficient hive bees, and the effects of food scarcity. We also conduct sensitivity studies and show the effects of parameter variations on the colony population. PMID:26148010

  16. Bridged Race Population Estimates

    Data.gov (United States)

    U.S. Department of Health & Human Services — Population estimates from "bridging" the 31 race categories used in Census 2000, as specified in the 1997 Office of Management and Budget (OMB) race and ethnicity...

  17. Market Squid Population Dynamics

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset contains population dynamics data on paralarvae, juvenile and adult market squid collected off California and the US Pacific Northwest. These data were...

  18. Populated Places of Iowa

    Data.gov (United States)

    Iowa State University GIS Support and Research Facility — This coverage contains points that represent populated places, ie. cities, towns, villages or any other named place where people live. The coverage was developed...

  19. EDUCATION AND ROMA POPULATION

    Directory of Open Access Journals (Sweden)

    Ana Asensio Belenguer

    2016-07-01

    Full Text Available This article deals with Education and the Roma Population. It presents an approach to schooling of Romani children since its outset in the city of Zaragoza (Spain. It analyzes the current status as presented by the Strategy for Social Inclusion of this people 2012-2020, and collects, from various sources, the fact that education remains a pending challenge for Roma Population. Measures to be taken by the educational community from a gender and inclusive perspective are proposed.

  20. Population Density Modeling Tool

    Science.gov (United States)

    2014-02-05

    194 POPULATION DENSITY MODELING TOOL by Davy Andrew Michael Knott David Burke 26 June 2012 Distribution...MARYLAND NAWCADPAX/TR-2012/194 26 June 2012 POPULATION DENSITY MODELING TOOL by Davy Andrew Michael Knott David Burke...Density Modeling Tool 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Davy Andrew Michael Knott David Burke 5d. PROJECT NUMBER

  1. Exploding Increase of Population

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.H. [Sunmoon University, Chonan (Korea)

    2002-03-01

    Until 1650, the population of the world did not increase properly. According to studies of the demography, the annual increase rate of the world population during 2500 years, from 850 B.C. to 1650 A.D., was just 0.07%. Currently, however, the world population, which has exceptionally rapidly increased from 1900, is more than 6 billion as of 2000. After World War II, especially, the increase rate of the population has risen to about 1.8%, so we can use the word, explosion of the population. The explosion of the population accompanies the increase of energy consumption. The energy production of every year cannot sufficiently meet the energy demand, so we can face the grand energy crisis someday. The date might be a someday after 2020. According to the future forecasting of Shell, one of the majors, the peak of oil supply will be between 2015 and 2020. Unless the alternative energy is developed, the whole world will suffer the serious oil crisis.

  2. Normative population theory.

    Science.gov (United States)

    Cowen, T

    1989-01-01

    This article finds utilitarian and contractarian approaches to solving the problem of optimal population unacceptable. The principles of utility refer to the best population as the one which contains the greatest sum of utility or the one with the highest average utility. Yet Parfits's repugnant conclusion states that these can imply a very large population at a very low standard of living. Cowen's Methuselah's Paradox says that for any possible happy and meaningful life, we can imagine another, much longer life which demonstrates the absurdity of the utility principles. Lewis argues for a conception of well being based upon choices over whole irreducible states of affairs, i.e., an ordinal concept of value. The contractarian approach assumes that we would rationally choose what type of life we were to live if the choice were made without anyone knowing his particular standing in the world--the veil of ignorance. This requires the individuals to choose on the basis of self interest, but gives too much weight to the individuals actually being born. The most promising population theory appears to be the ideal participant method. Simply stated the optimal population is what an individual would prefer if he had to sequentially live out each life in his choice. Further, this method may be able to reduce the difficulties with evaluating alternate populations to the common problem of aggregating disparate preferences.

  3. Establish a Bioassay to Assess Nematicidal Effect of Bacillus thuringiensis Crystal Protein against Meloidogyne hapla%苏云金芽孢杆菌晶体蛋白对北方根结线虫生物测定方法的建立和杀虫效果评价

    Institute of Scientific and Technical Information of China (English)

    余子全; 刘斌; 邹雪; 喻子牛; 孙明

    2008-01-01

    A bioassay procedure was developed to assess the toxicity of Bacillus thuringiensis crystal protein against Meloidogyne hapla, a root-knot nematode, under laboratory conditions. Reproducibility and precision of the bioassay results were optimal when forty 2nd stage juveniles were incubated in the dissolved crystal pro- tein solution at 25℃, pH9.0 for 7 days. The juveniles were stained with 1% KMnO4 for 2 hours or methylene blue solution for 1 hour to distinguish riving and dead ones. By the bioassay procedure, the LC50 value of strain YBT-1532 crystal protein against M. Hapla was determined as 0.304±0.086 mg/mL ( LC50±1.96SE). Moreover, the strain YBT-1532 showed toxicity to Caenorhabditis elegans, a free-living nematode. All results indicated that YBT-1532 is a toxic strain to plant-parasitic nematode, and has the potential to control plant- parasitic nematode.

  4. First China Population Award.

    Science.gov (United States)

    1993-10-01

    The China Population Award is given every two years for family planning implementation, science, and technology, and honorary achievements. The winners for the First China Population Award were as follows: Mr. Zhao Zhihao, governor of Shandong province; Mme. Shang Dewei, retired from the Shanghai family planning committee; Mme. Cui Peihua, director of the Nanche Village, Shidao Town, Rongcheng City, Shandong Province, Family Planning Office; Mme. Xu Aiguang, director of Zhejiang Family Planning Committee; Mr. Ye Wenshi, secretary of Guanghan City Party Committee, Sichuan province; Mr. Zhang Zhiyuan, president of Liaoning Family Planning Association; Mme. Shou Haizhen, director of Jiangsu Family Planning Committee for family planning implementation. Mme. Yan Renying, vice president of the China Family Planning Association, Mr. Wu Jieping, vice president of the China Family Planning Association, and Mr. Lie Zheng (deceased), former president of the Population Association of China received prized for achievements in science and technology. Mr. Ma Yinchu (decreased) honorary president of Peking University, received an honorary prize for his creative views on the contradictions between rapid population growth and increased capital wealth. He recommended population control and improvement in quality of human resources. He recommended the practice of deferred marriage and other solutions to China's population problems. As an ultra-leftist, he was severely criticized, but redeemed in 1981 shortly before he died. The science and technology awards went to Mr. Zheng who established the first population research institute and suggested that reproduction be in balance with material resources. Mr. Jieping was a medical specialist and contributed to research on male birth control. Mme. Renying, as an obstetrician and gynecologist, researched use of prostaglandin injections for ending early pregnancy and reversible female sterilization. She was active in efforts of prevention of

  5. Population pressure rising.

    Science.gov (United States)

    1994-08-01

    Even though the ESCAP region has been successful in slowing population growth, Asia will account for half of the global population increase every year, or about 1 billion persons in the next quarter century, according to a new report by the Asian Development Bank (ADB). That report, entitled "Population Policy Paper," states that Asia will be the global center of population aging largely because of big increases in the number of persons over the age of 65 in China, Japan and the region's newly industrializing economies. "By the year 2000, 86% of the world's aged will be in the Asia-Pacific region and by the year 2025 there are projected to be 687 million persons over the age of 65 in the region, placing unprecedented strains on economic and social systems far beyond what traditional extended family networks can absorb," the paper says. But the report also considers other aspects of overall population increase. "The prospect of an additional billion or so people in Asia over the next 25 years is daunting, since the implications for poverty, economic growth, unemployment and environmental quality are immense," it adds. The region's economies will have to scramble to generate jobs and livelihoods for tens of millions of young people for the next several decades. Rural-to-urban migration trends threaten the collapse of urban infrastructure, with the social tensions and political instability that such troubles bring, the report states.

  6. Frequency Population Growth Rate

    Directory of Open Access Journals (Sweden)

    Nouralah Salehi Asfiji

    2012-10-01

    Full Text Available The Solow growth model assumes that labor force grows exponentially. That is not a realistic assumption. In generalized logistic equations that describes more accurately population growth. Economic growth is not a smooth process. Real GDP has fluctuations in the growth rate. We call these fluctuations business cycles. Business cycle theory came about from the failures of classical economics in being able to illuminate on the causes of the Great Depression. The logistic growth model to explain changes in population growth rates are not. In this paper a new analysis of the population growth rate in the frequency space is described with mathematical logic and economic reasoning, so that, firstly, to a higher level of capital per capita, or at least equal to the Solow growth model reaches Second, the limits of saturation (Carrying-Capacity is not, and ultimately, population growth rates have an impact on long-term per capita amounts. The initial classic assumption is changed in this article based on the available frequencies in the population growth equation.

  7. Population and Climate Change

    Science.gov (United States)

    O'Neill, Brian C.; Landis MacKellar, F.; Lutz, Wolfgang

    2000-11-01

    Population and Climate Change provides the first systematic in-depth treatment of links between two major themes of the 21st century: population growth (and associated demographic trends such as aging) and climate change. It is written by a multidisciplinary team of authors from the International Institute for Applied Systems Analysis who integrate both natural science and social science perspectives in a way that is comprehensible to members of both communities. The book will be of primary interest to researchers in the fields of climate change, demography, and economics. It will also be useful to policy-makers and NGOs dealing with issues of population dynamics and climate change, and to teachers and students in courses such as environmental studies, demography, climatology, economics, earth systems science, and international relations.

  8. Asymetric Pavlovian Populations

    CERN Document Server

    Bournez, Olivier; Cohen, Johanne; Koegler, Xavier; Rabie, Mikael

    2011-01-01

    Population protocols have been introduced by Angluin et al. as a model of networks consisting of very limited mobile agents that interact in pairs but with no control over their own movement. A collection of anonymous agents, modeled by finite automata, interact pairwise according to some rules that update their states. Predicates on the initial configurations that can be computed by such protocols have been characterized as semi-linear predicates. In an orthogonal way, several distributed systems have been termed in literature as being realizations of games in the sense of game theory. We investigate under which conditions population protocols, or more generally pairwise interaction rules, correspond to games. We show that restricting to asymetric games is not really a restric- tion: all predicates computable by protocols can actually be computed by protocols corresponding to games, i.e. any semi-linear predicate can be computed by a Pavlovian population multi-protocol.

  9. Quenched effective population size

    CERN Document Server

    Sagitov, Serik; Vatutin, Vladimir

    2010-01-01

    We study the genealogy of a geographically - or otherwise - structured version of the Wright-Fisher population model with fast migration. The new feature is that migration probabilities may change in a random fashion. Applying Takahashi's results on Markov chains with random transition matrices, we establish convergence to the Kingman coalescent, as the population size goes to infinity. This brings a novel formula for the coalescent effective population size (EPS). We call it a quenched EPS to emphasize the key feature of our model - random environment. The quenched EPS is compared with an annealed (mean-field) EPS which describes the case of constant migration probabilities obtained by averaging the random migration probabilities over possible environments.

  10. Distance Learning for Special Populations

    Science.gov (United States)

    Bates, Rodger A.

    2012-01-01

    Distance education strategies for remotely deployed, highly mobile, or institutionalized populations are reviewed and critiqued. Specifically, asynchronous, offline responses for special military units, Native Americans on remote reservations, prison populations and other geographically, temporally or technologically isolated niche populations are…

  11. Cancer among circumpolar populations

    DEFF Research Database (Denmark)

    Young, T Kue; Kelly, Janet J; Friborg, Jeppe

    2016-01-01

    registries, with direct age-standardization of rates to the world standard population. For comparison, the "world average" rates as reported in the GLOBOCAN database were used. FINDINGS: Age-standardized incidence rates by cancer sites were computed for the 8 Arctic States and 20 of their northern regions......, averaged over the decade 2000-2009. Cancer of the lung and colon/rectum in both sexes are the commonest in most populations. We combined the Inuit from Alaska, Northwest Territories, Nunavut and Greenland into a "Circumpolar Inuit" group and tracked cancer trends over four 5-year periods from 1989 to 2008...

  12. Reconceptualization of Population Education.

    Science.gov (United States)

    Sikes, O. J.

    1993-01-01

    Discusses eight aspects of the reorganization of population education: (1) need for clear objectives; (2) emerging concerns about content; (3) prioritization of contents; (4) involvement of parents; (5) approaches to teaching; (6) teacher training; (7) evaluation issues; and (8) institutionalization. (MDH)

  13. Populism in Latin America

    Science.gov (United States)

    2009-03-20

    a profound constitutional reform through the National Congress. The goal is always to adapt the democratic system and subordinate it to the personal...to the democratic system of a country that has become immersed in populism. The other inevitably involves 21 control of the media, the military

  14. Population and Development Issues.

    Science.gov (United States)

    Cohen, Sharon; Garran, Christopher

    1998-01-01

    Describes a unit on demographics for a high school world-history course that addresses questions of uneven population growth and the "problem of global overpopulation." Provides a detailed outline of the two-day unit including unit and daily goals and objectives, daily activities and questions, and ideas for further student research. (DSK)

  15. Multiphoton coherent population oscillation

    CERN Document Server

    Sharypov, A V

    2014-01-01

    We study the bichromatic driving of a two-level system which displays long-lived coherent population oscillations (CPO). We show that under certain conditions, multiphoton parametric interaction leads to the appearance of CPO resonances at the subharmonic frequencies. In addition, in the region of the CPO resonances, there is strong parametric interaction between the weak sideband components of the electromagnetic field.

  16. Adam Smith on population.

    Science.gov (United States)

    Spengler, J J

    1970-11-01

    Abstract Adam Smith dealt with questions of population mainly in his Wealth of Nations. His discussion falls roughly under five heads and reflects in considerable measure his image of the English economy. (1) A country's population capacity, given the average level of consumption, was conditioned by the stock of land, the skill with which it was cultivated, and the degree to which division of labour could be increased and thereby augment output for domestic use and sale in external markets. (2) Growth of population was essentially in response to growth of the demand for labour and served to increase division of labour. (3) The social mechanisms underlying elevation of the scale of living are touched upon, and in an optimistic spirit. (4) The distribution of a country's population responded to its progress in opulence, with the rate of this progress conditioned by the degree to which inappropriate (e.g. mercantilist) policies were avoided. (5) Smith dealt briefly with such matters as colonies, education, size of economy, environmental influences, and public policy, all of which he recognized as significant for the quantity and quality of a country's numbers.

  17. [Population trends and poverty].

    Science.gov (United States)

    Olmedo, C

    1998-04-01

    Implications of population growth in Ecuador for the quality of life of the poor population are analyzed. It is argued that if the gross national product (GNP) were to grow at a sustained annual rate of 5% or more, demographic trends would not present a significant obstacle to reducing poverty. National economic projections are for growth of only 2.5-3.5% annually. The continuing rapid growth of the poor population despite general slowing of demographic growth, the young age structure, the need for increased formal education to enable the poor to overcome their poverty, and the effect of unemployment on the dependency ratio will tend to hamper improvements in average productivity and per capita GNP. The need for spending on education, health, basic services, and housing will divert funds away from productive investment, generating a direct negative impact on economic growth. Over half of Ecuadorian children suffer from some degree of malnutrition, indicating that food production is inadequate to meet demand. The export-oriented agricultural policy and poor weather have led to a chronic shortage of basic foods. Progressive increase and diversification of agricultural production, along with maintenance of low prices and substantial increases in income levels and agricultural productivity, will be required if the entire population is to be fed adequately. Intense efforts will be needed from all sectors to bring demographic growth into balance with economic and development needs.

  18. Relics: penguin population programs.

    Science.gov (United States)

    Sun, L; Xie, Z

    2001-01-01

    What has been responsible for the increase in Chinstrap penguin populations during the past 40 years in maritime Antarctica? One view ascribes it to an increase in availability of their prey brought on by the decrease in baleen whale stocks. The contrary opinion, attributes it to environmental warming. This causes a gradual decrease in the frequency of cold years with extensive winter sea ice cover. A number of penguin monitoring programs are in progress and are expected to provide some answers to these questions. Unfortunately, it is not easy to distinguish natural variability from anthropogenic change since penguins are easily accessible predators of krill and the feeding range of the penguins has almost overlapped with the krill fishery in time and space in the last four decades. Therefore it is important to reconstruct the change of ancient penguin abundance and distribution in the absence of human activity. Many efforts have focused on surveying the abandoned penguin rookeries, but this method has not been able to give a continuous historical record of penguin populations. In several recent studies, ancient penguin excreta was scooped from the penguin relics in the sediments of the lake on penguin rookery, Ardley Island, maritime Antarctica. In these studies, penguin droppings or guano soil deposited in the lake and changes in sediment geochemistry have been used to calculate penguin population changes based upon the geochemical composition of the sediment core. The results suggest that climate change has a significant impact on penguin populations.

  19. Africa population dynamics

    NARCIS (Netherlands)

    Akinyoade, A.; Damen, J.C.M.; Dietz, A.J.; Kilama, B.; Omme, van G.

    2014-01-01

    Africa's population has grown extremely rapidly over the last fifty years from 289 million inhabitants in 1961 to more than 1 billion today. This is a growth rate of 350% in just half a century and the number of urban residents has increased even more quickly: from 65 million in 1960 to 460 million

  20. China Population and Developmenl

    Institute of Scientific and Technical Information of China (English)

    2004-01-01

    The Cairo International Conference on Population and Development (ICPD) paid great attention to the sexual and reproductive health of adolescents. One of the top priorities of the ICPD Programme of Action is to provide adolescents with necessary sexual and reproductive health information and services, ensure their right to reproductive health education and services, and help them develop risk-free behaviours and healthy lifestyles.

  1. Charting Population Shifts

    Institute of Scientific and Technical Information of China (English)

    LI LI

    2010-01-01

    @@ China is updating its demographic information through its once-in-adecade population census.The latest database will be used as an important reference for the country to draft its development plan for the next five years and deal with social problems,such as an aging society and imbalanced gender ratio,according to experts.

  2. The Problem of Population

    Institute of Scientific and Technical Information of China (English)

    刘香情; 钱丹

    2002-01-01

    With the population growing, a lot of problems have come out, Nowadays a lot of tall buildings have been built, but the houses are still very short; A lot of cars and buses have increased, but they are still crowded with people; A lot of schools have been built,

  3. Larvicidal and nematicidal activities of the leaf essential oil of Croton regelianus.

    Science.gov (United States)

    Torres, Maria Conceição M; Assunção, João Carlos; Santiago, Gilvandete Maria P; Andrade-Neto, Manoel; Silveira, Edilberto R; Costa-Lotufo, Leticia V; Bezerra, Daniel P; Marinho Filho, José Delano B; Viana, Francisco Arnaldo; Pessoa, Otília Deusdênia L

    2008-12-01

    The chemical composition of the leaf essential oil of Croton regelianus collected from wild plants growing in two different sites at Ceará State (Brazil) was analyzed by GC/MS and GC-FID. Twenty monoterpenoids, representing more than 96% of the chemical composition of the oils, were identified and quantified. The oils showed similar chemical composition but considerable variation in the levels of each constituent. Ascaridole (33.9-17.0%), p-cymene (22.3-21.6%), and camphor (13.0-3.1%) were the predominant constituents. The monoterpene ascaridole was isolated and characterized by spectroscopic data. The essential oils and the isolated compounds were tested against Aedes aegypti and Artemia sp. larvae, and the root knot nematode Meloidogyne incognita. The bioassay results show that the essential oil of C. regelianus and ascaridole were moderately active against the M. incognita, but strongly effective against both A. aegypti and Artemia sp. larvae.

  4. Discussion Forum--Population Theories: Their Implications on Population Education.

    Science.gov (United States)

    Population Education in Asia and the Pacific Newsletter, 1983

    1983-01-01

    Contends that unless population education programs have a clear conceptual framework built upon a consistent set of population theories, they will remain merely as appendices to established school projects. Several population theories and their implications for population education are described. These include Malthusian demographic transition,…

  5. [Vietnam and its population].

    Science.gov (United States)

    Veron, J

    1993-01-01

    Viet Nam's 1993 population of 72 million makes it the second largest country of Southeast Asia after Indonesia. Viet Nam's demographic transition is underway, but growth is still a rapid 2% annually, a sufficiently high rate to hinder socioeconomic development. The 1979 and 1989 censuses and the 1988 Demographic and Health Survey are the major recent sources of data on Viet Nam's population. Marriage is universal in Viet Nam. Men marry at 24.5 and women at 23.2 years on average. Fertility estimates based on nonadjusted census data indicate a total fertility rate for 1988-89 of 3.8 overall, 2.2 in urban areas, and 4.3 in rural areas. Regional differences resulting from contraceptive usage, educational differentials, and tabus regarding spacing are strong. The average household size is 5. Viet Nam's first fertility reduction policy was announced in 1963 and sought to improve the welfare of women to increase their productivity for the war effort. More recent family planning policies are based on the view that rapid demographic growth is one of the great obstacles to development. The objectives of the current policy are to reduce the growth rate to 1% by the end of the century, increase contraceptive prevalence, delay arrival of the first child, limit family size to 2 children or 3 for ethnic minorities, and increase birth intervals from 3 to 5 years. The program is voluntarist in nature but includes incentives and disincentives. Life expectancy at birth in 1989 was 67.5 years for women and 63 for men. Infant mortality was 37/1000, with regional differentials. The principal causes of hospital deaths are tuberculosis, malaria, and diarrhea. Objectives of the current health policy are to prevent infectious diseases, reinforce primary health care services, promote traditional medicine, achieve self-sufficiency in basic medicines, and improve environmental health and access to clean water. Viet Nam is one of the most densely populated Southeast Asian countries and is still

  6. On optimal population paths

    CERN Document Server

    Lane, John S

    1977-01-01

    The overall purpose of this monograph is to integrate and critically evaluate the existing literature in the area of optimal joint savings population programs. The existing diverse presentations are all seen to be discussions within a unified framework. The central problem is to compare the desirability of alternative inter-temporal sequences of total savings and population sizes. Of critical importance is whether one regards persons as the fundamental moral entities or whether one takes Sidgwick's viewpoint that something good being the result of one's action is the baSic reason for dOing anything. The latter viewpoint is consistent with defining a complete social preference ordering over these alternative sequences. Since part of one's interest is to evaluate the consequences of various ethical beliefs a com­ parative study of several such orderings is presented; in particular the Mill-Wolfe average utilitarian, and Sidgwick-Meade classical utilitarian) formulations. A possible problem with the social pref...

  7. Population, desertification, and migration.

    Science.gov (United States)

    Westing, A H

    1994-01-01

    When an imbalance develops between population numbers and the carrying capacity of the land, the persons thereby displaced are referred to as environmental refugees. The utilization of the land beyond sustainability leads to land degradation and ultimately, desertification. The social and political impacts of long-term environmental migration can be distinguished: a) at the site of origin of the displaced persons by the residual population; b) at rural sites of destination within the nation between the new arrivals and preestablished populations; c) in the cities within the nation; d) in the nonindustrialized foreign countries; and e) in the industrialized foreign countries. In the event that an area which had previously been devoted to pastoralism is converted to agriculture, the displaced pastoralists might respond through armed rebellion. In some instances, the disenchanted urban squatters become a politically restive and even a destabilizing force, as occurred in Sudan in the 1980s, especially in Khartoum and Port Sudan. The foreign countries to which many of the displaced persons are migrating are subjected to increasing levels of migrant-induced economic, cultural, and political strains. The growing problems associated with south-to-north migration across the Mediterranean Sea have recently led France, Italy, Portugal, and Spain to enter into a consultative arrangement with Algeria, Libya, Mauritania, Morocco, and Tunisia. All foreign aid to the nonindustrialized countries that attempts to ameliorate the problem of desertification must adopt integrated approaches that: a) address population issues; b) support environmental education; c) provide for the protection of biodiversity; d) encourage participatory forms of local and national government; e) provide opportunities for income generation outside the livestock sector; and f) foster political security and facilitate ecogeographical (subregional) cooperation.

  8. Population and health policies

    OpenAIRE

    Schultz, T.Paul

    2009-01-01

    The program evaluation literature for population and health policies is in flux, with many disciplines documenting biological and behavioral linkages from fetal development to late life mortality, chronic disease, and disability, though their implications for policy remain uncertain. Both macro- and microeconomics seek to understand and incorporate connections between economic development and the demographic transition. The focus here is on research methods, findings, and questions that econo...

  9. [Population, ethics and equity].

    Science.gov (United States)

    Berlinguer, G

    1997-01-01

    "Demography is, explicitly and not, imbued with an [ethical] content.... As demography involves both public policies and individual choices, the [ethical] slant should be [examined]. Thus, what we have on the one hand is an [ethical] state, which dictates its citizens' personal behaviour and, on the other, a state based on liberty, backed up by three shared values: human rights, pluralism and equality. This article looks at how today these may be reinterpreted when making decisions regarding the population." (EXCERPT)

  10. INCASOY-35: PRIMERA VARIEDAD DE SOYA OBTENIDA EN CUBA A PARTIR DEL EMPLEO DE TÉCNICAS DE IRRADIACIÓN DE RAYOS GAMMA DE 60Co

    Directory of Open Access Journals (Sweden)

    R. Ortiz

    2005-01-01

    Full Text Available La variedad INCASoy-35 fue obtenida a partir de la irradiación de semillas de la variedad INCASoy-15 con dosis de 240 Gy de rayos gamma 60Co; esta variedad se adapta a siembras de primavera, verano e invierno y puede alcanzar rendimientos de 3 t.ha-1 de granos. Tolera las principales plagas y enfermedades y, en especial, resiste el ataque de nemátodos Meloidogyne incognita. En la época adversa de primavera, las semillas han mostrado tolerancia al deterioro. Tiene capacidad de garantizar altas producciones con bajos insumos, por lo que resulta factible para la agricultura cubana.

  11. Complete genome sequence of Bacillus thuringiensis YC-10, a novel active strain against plant-parasitic nematodes.

    Science.gov (United States)

    Cheng, Feixue; Wang, Jian; Song, Zhiqiang; Cheng, Ju'e; Zhang, Deyong; Liu, Yong

    2015-09-20

    Bacillus thuringiensis is an important microbial biopesticide for controlling agricultural pests by the production of toxic parasporal crystals proteins.Here,we report the finished annotated genome sequence of B. thuringiensis YC-10,which is highly toxic to nematodes.The complete genome sequence consists of a circular chromosome and nine circular plasmids,which the biggest plasmid harbors six parasporal crystals proteins genes consisting of cry1Aa, cry1Ac, cry1Ia, cry2Aa, cry2Ab and cryB1. The crystals proteins of Cry1Ia and Cry1Aa have high nematicidal activity against Meloidogyne incognita.

  12. Studies onPaecilomyces marquandii from nematode suppressive chinampa soils.

    Science.gov (United States)

    Marban-Mendoza, N; Garcia-E, R; Dicklow, M B; Zuckerman, B M

    1992-05-01

    Two applications of isolates ofPaecilomyces marquandii from suppressive chinampa soils or P. lilacinus from Peru, fungi that parasitize nematode eggs, generally gave better control of tomato root-knot due toMeloidogyne incognita than did a single application. The effects on root galling by each of thePaecilomyces isolates varied between experiments; however, the ovicidal potential of the three isolates did not differ significantly. Proteins specific for each of the isolates were demonstrated by SDS gel electrophoresis. The results indicate thatP. marquandii is one of the natural soil organisms that contribute to nematode suppression in the chinampa agricultural soils.

  13. Plant-parasitic Nematode Acetylcholinesterase Inhibition by Carbamate and Organophosphate Nematicides.

    Science.gov (United States)

    Opperman, C H; Chang, S

    1990-10-01

    The sensitivity of acetylcholinesterases (ACHE) isolated from the plant-parasitic nematodes Meloidogyne arenaria, M. incognita, and Heterodera glycines and the free-living nematode Caenorhabditis elegans to carbamate and organophosphate nematicides was examined. The AChE from plant-parasitic nematode species were more sensitive to carbamate inhibitors than was AChE from C. elegans, but response to the organophosphates was approximately equivalent. The sulfur-containing phosphate nematicides were poor inhibitors of nematode acetylcholinesterase, but treatment with an oxidizing agent greatly improved inhibition. Behavioral bioassays with living nematodes revealed a poor relationship between enzyme inhibition and expression of symptoms in live nematodes.

  14. Histone Acylation beyond Acetylation: Terra Incognita in Chromatin Biology

    Directory of Open Access Journals (Sweden)

    Sophie Rousseaux

    2015-04-01

    Full Text Available Histone acetylation, one of the first and best studied histone post-translational modifications (PTMs, as well as the factors involved in its deposition (writers, binding (readers and removal (erasers, have been shown to act at the heart of regulatory circuits controlling essential cellular functions. The identification of a variety of competing histone lysine-modifying acyl groups including propionyl, butyryl, 2-hydroxyisobutyryl, crotonyl, malonyl, succinyl and glutaryl, raises numerous questions on their functional significance, the molecular systems that manage their establishment, removal and interplay with the well-known acetylation-based mechanisms. Detailed and large-scale investigations of two of these new histone PTMs, crotonylation and 2-hydroxyisobutyrylation, along with histone acetylation, in the context of male genome programming, where stage-specific gene expression programs are switched on and off in turn, have shed light on their functional contribution to the epigenome for the first time. These initial investigations fired many additional questions, which remain to be explored. This review surveys the major results taken from these two new histone acylations and discusses the new biology that is emerging based on the diversity of histone lysine acylations.

  15. Chemical proteomics: terra incognita for novel drug target profiling

    Institute of Scientific and Technical Information of China (English)

    Fuqiang Huang; Boya Zhang; Shengtao Zhou; Xia Zhao; Ce Bian; Yuquan Wei

    2012-01-01

    The growing demand for new therapeutic strategies in the medical and pharmaceutic fields has resulted in a pressing need for novel druggable targets.Paradoxically,however,the targets of certain drugs that are already widely used in clinical practice have largely not been annotated.Because the pharmacologic effects of a drug can only be appreciated when its interactions with cellular components are clearly delineated,an integrated deconvolution of drug-target interactions for each drug is necessary.The emerging field of chemical proteomics represents a powerful mass spectrometry (MS)-based affinity chromatography approach for identifying proteome-wide small molecule-protein interactions and mapping these interactions to signaling and metabolic pathways.This technique could comprehensively characterize drug targets,profile the toxicity of known drugs,and identify possible off-target activities.With the use of this technique,candidate drug molecules could be optimized,and predictable side effects might consequently be avoided.Herein,we provide a holistic overview of the major chemical proteomic approaches and highlight recent advances in this area as well as its potential applications in drug discovery.

  16. Brazil Nut Effect and CONCRETE: Entering Terra Incognita

    NARCIS (Netherlands)

    Stroeven, P.; He, H.

    2012-01-01

    This paper presents some evidence of the impact of the Brazil nut effect (BNE) on concrete’s particulate structure on meso-level (aggregate) as well as on micro-level (cement paste). BNE is associated with long-range size segregation in particle mixtures due to vibration in slurry state of concrete,

  17. Extra-terra incognita: Martian maps in the digital age.

    Science.gov (United States)

    Messeri, Lisa

    2017-02-01

    Science and technology studies (STS) and critical cartography are both asking questions about the ontological fixity of maps and other scientific objects. This paper examines how a group of NASA computer scientists who call themselves The Mapmakers conceptualizes and creates maps in service of different commitments. The maps under construction are those of alien Mars, produced through partnerships that NASA has established with Google and Microsoft. With the goal of bringing an experience of Mars to as many people as possible, these maps influence how we imagine our neighbouring planet. This paper analyzes two attributes of the map, evident in both its representation and the attending cartographic practices: a sense of Mars as dynamic and a desire for a democratic experience of Mars in which up-to-date Mars data can be intuitively accessed not only by scientists but by lay users as well. Whereas a democratic Mars promises users the ability to decide how to interact with the map and understand Mars, dynamic Mars imposes a more singular sense of Mars as a target of continued robotic and maybe even human exploration. Because maps of Mars have a different (and arguably less complex) set of social and political commitments than those of Earth, they help us see how different goals contradict and complement each other in matters of exploration and state-craft relevant both to other worlds and our own.

  18. 从populations谈population

    Institute of Scientific and Technical Information of China (English)

    刘超

    2000-01-01

    高中英语课本第二册第9单元里有这样一个句子:“Many parts of the world.which once had large populations and produced plenty of crops.have become deserts.”(世界上很多地区,一度人口众多。生产过大量农作物,现在已经变成沙漠了。)这就说明,表“人口”一般用population,也可以用populations。

  19. Diabetes in population isolates

    DEFF Research Database (Denmark)

    Grarup, Niels; Moltke, Ida; Albrechtsen, Anders

    2015-01-01

    Type 2 diabetes (T2D) is an increasing health problem worldwide with particularly high occurrence in specific subpopulations and ancestry groups. The high prevalence of T2D is caused both by changes in lifestyle and genetic predisposition. A large number of studies have sought to identify...... on glucose-stimulated plasma glucose, serum insulin levels, and T2D. The variant defines a specific subtype of non-autoimmune diabetes characterized by decreased post-prandial glucose uptake and muscular insulin resistance. These and other recent findings in population isolates illustrate the value...

  20. Playing With Population Protocols

    Directory of Open Access Journals (Sweden)

    Xavier Koegler

    2009-06-01

    Full Text Available Population protocols have been introduced as a model of sensor networks consisting of very limited mobile agents with no control over their own movement: A collection of anonymous agents, modeled by finite automata, interact in pairs according to some rules. Predicates on the initial configurations that can be computed by such protocols have been characterized under several hypotheses. We discuss here whether and when the rules of interactions between agents can be seen as a game from game theory. We do so by discussing several basic protocols.

  1. [Roma populations and health].

    Science.gov (United States)

    Jackson, Y; Tabin, J P; Hourton, G; Bodenmann, P

    2015-03-25

    The health status of the so-called "Roma" is usually much poorer than that of neighbouring non-Roma populations with a life expectancy gap of 5-15 years. This results from prolonged exposure to adverse determinants of health and to persistent exclusion from social and political arenas. Scientific and social research has only poorly addressed the health issues of Roma and evidences are scarce. Insufficient access to public services, including to health care and non optimal clinical practices are modifiable factors. If correctly addressed, this could contribute to reduce health disparities, including in Switzerland.

  2. Density Estimation in Several Populations With Uncertain Population Membership

    KAUST Repository

    Ma, Yanyuan

    2011-09-01

    We devise methods to estimate probability density functions of several populations using observations with uncertain population membership, meaning from which population an observation comes is unknown. The probability of an observation being sampled from any given population can be calculated. We develop general estimation procedures and bandwidth selection methods for our setting. We establish large-sample properties and study finite-sample performance using simulation studies. We illustrate our methods with data from a nutrition study.

  3. Innovations in Population Education: Conveying Population Education through Games.

    Science.gov (United States)

    Villanueva, Carmelita L., Ed.

    1987-01-01

    The use of games and simulations is a method that educators are finding especially useful in presenting information about population concerns. The "Futures Wheels" is a participatory classroom exercise, designed to demonstrate probable consequences of future population increases and is also used to illustrate a wide range of population related…

  4. Training Manual in Population Education. Population Education Programme Service.

    Science.gov (United States)

    United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and Oceania.

    Population education is at different stages of development in the Asian countries, but almost all of the countries show an interest in developing population education programs. This manual for designing and implementing population education programs consists of six chapters. Chapter one highlights issues and problems arising in connection with…

  5. Population III Hypernovae

    CERN Document Server

    Smidt, Joseph; Even, Wesley; Wiggins, Brandon; Johnson, Jarrett L; Fryer, Chris L

    2014-01-01

    Population III supernovae have been of growing interest of late for their potential to directly probe the properties of the first stars, particularly the most energetic events that are visible near the edge of the observable universe. But until now, hypernovae, the unusually energetic Type Ib/c supernovae that are sometimes associated with gamma-ray bursts, have been overlooked as cosmic lighthouses at the highest redshifts. In this, the latest of a series of studies on Population III supernovae, we present numerical simulations of 25 - 50 M$_{\\odot}$ hypernovae and their light curves done with the Los Alamos RAGE and SPECTRUM codes. We find that they will be visible at z = 10 - 15 to the James Webb Space Telescope (JWST) and z = 4 - 5 to the Wide-Field Infrared Survey Telescope (WFIRST), tracing star formation rates in the first galaxies and at the end of cosmological reionization. If, however, the hypernova crashes into a dense shell ejected by its progenitor, a superluminous event will occur that may be se...

  6. POPULATION III HYPERNOVAE

    Energy Technology Data Exchange (ETDEWEB)

    Smidt, Joseph; Whalen, Daniel J. [T-2, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Wiggins, Brandon K. [Department of Physics and Astronomy, Brigham Young University, Provo, UT 84602 (United States); Even, Wesley; Fryer, Chris L. [CCS-2, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Johnson, Jarrett L., E-mail: dwhalen1999@gmail.com [XTD-PRI, Los Alamos National Laboratory, Los Alamos, NM 87545 (United States)

    2014-12-20

    Population III supernovae have been of growing interest of late for their potential to directly probe the properties of the first stars, particularly the most energetic events that are visible near the edge of the observable universe. Until now, hypernovae, the unusually energetic Type Ib/c supernovae that are sometimes associated with gamma-ray bursts, have been overlooked as cosmic beacons at the highest redshifts. In this, the latest of a series of studies on Population III supernovae, we present numerical simulations of 25-50 M {sub ☉} hypernovae and their light curves done with the Los Alamos RAGE and SPECTRUM codes. We find that they will be visible at z = 10-15 to the James Webb Space Telescope and z = 4-5 to the Wide-Field Infrared Survey Telescope, tracing star formation rates in the first galaxies and at the end of cosmological reionization. If, however, the hypernova crashes into a dense shell ejected by its progenitor, it is expected that a superluminous event will occur that may be seen at z ∼ 20 in the first generation of stars.

  7. The Resonant Transneptunian Populations

    CERN Document Server

    Gladman, B; Petit, J-M; Kavelaars, J; Jones, R L; Parker, J Wm; Van Laerhoven, C; Nicholson, P; Rousselot, P; Bieryla, A; Ashby, M L N

    2012-01-01

    The transneptunian objects (TNOs) trapped in mean-motion resonances with Neptune were likely emplaced there during planet migration late in the giant-planet formation process. We perform detailed modelling of the resonant objects detected in the Canada-France Ecliptic Plane Survey (CFEPS) in order to provide population estimates and, for some resonances, constrain the complex internal orbital element distribution. Detection biases play a critical role because phase relationships with Neptune make object discovery more likely at certain longitudes. This paper discusses the 3:2, 5:2, 2:1, 3:1, 5:1, 4:3, 5:3, 7:3, 5:4, and 7:4 mean-motion resonances, all of which had CFEPS detections, along with our upper limit on 1:1 Neptune Trojans (which is consistent with their small population estimated elsewhere). For the plutinos (TNOs in the 3:2 resonance) we refine the orbital element distribution given in Kavelaars et al. (2009) and show that steep H-magnitude distributions (N(H) proportional to 10aH, with a=0.8-0.9) a...

  8. Correlations and Neuronal Population Information.

    Science.gov (United States)

    Kohn, Adam; Coen-Cagli, Ruben; Kanitscheider, Ingmar; Pouget, Alexandre

    2016-07-01

    Brain function involves the activity of neuronal populations. Much recent effort has been devoted to measuring the activity of neuronal populations in different parts of the brain under various experimental conditions. Population activity patterns contain rich structure, yet many studies have focused on measuring pairwise relationships between members of a larger population-termed noise correlations. Here we review recent progress in understanding how these correlations affect population information, how information should be quantified, and what mechanisms may give rise to correlations. As population coding theory has improved, it has made clear that some forms of correlation are more important for information than others. We argue that this is a critical lesson for those interested in neuronal population responses more generally: Descriptions of population responses should be motivated by and linked to well-specified function. Within this context, we offer suggestions of where current theoretical frameworks fall short.

  9. CDC WONDER: Population (from Census)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Population online databases contain data from the US Census Bureau. The Census Estimates online database contains contains county-level population counts for...

  10. CDC WONDER: Population (from Census)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Population online databases contain data from the US Census Bureau. The Census Estimates online database contains county-level population counts for years 1970 -...

  11. NASA Orbital Debris Baseline Populations

    Science.gov (United States)

    Krisko, Paula H.; Vavrin, A. B.

    2013-01-01

    The NASA Orbital Debris Program Office has created high fidelity populations of the debris environment. The populations include objects of 1 cm and larger in Low Earth Orbit through Geosynchronous Transfer Orbit. They were designed for the purpose of assisting debris researchers and sensor developers in planning and testing. This environment is derived directly from the newest ORDEM model populations which include a background derived from LEGEND, as well as specific events such as the Chinese ASAT test, the Iridium 33/Cosmos 2251 accidental collision, the RORSAT sodium-potassium droplet releases, and other miscellaneous events. It is the most realistic ODPO debris population to date. In this paper we present the populations in chart form. We describe derivations of the background population and the specific populations added on. We validate our 1 cm and larger Low Earth Orbit population against SSN, Haystack, and HAX radar measurements.

  12. Population, migration and urbanization.

    Science.gov (United States)

    1982-06-01

    Despite recent estimates that natural increase is becoming a more important component of urban growth than rural urban transfer (excess of inmigrants over outmigrants), the share of migration in the total population growth has been consistently increasing in both developed and developing countries. From a demographic perspective, the migration process involves 3 elements: an area of origin which the mover leaves and where he or she is considered an outmigrant; the destination or place of inmigration; and the period over which migration is measured. The 2 basic types of migration are internal and international. Internal migration consists of rural to urban migration, urban to urban migration, rural to rural migration, and urban to rural migration. Among these 4 types of migration various patterns or processes are followed. Migration may be direct when the migrant moves directly from the village to the city and stays there permanently. It can be circular migration, meaning that the migrant moves to the city when it is not planting season and returns to the village when he is needed on the farm. In stage migration the migrant makes a series of moves, each to a city closer to the largest or fastest growing city. Temporary migration may be 1 time or cyclical. The most dominant pattern of internal migration is rural urban. The contribution of migration to urbanization is evident. For example, the rapid urbanization and increase in urban growth from 1960-70 in the Republic of Korea can be attributed to net migration. In Asia the largest component of the population movement consists of individuals and groups moving from 1 rural location to another. Recently, because urban centers could no longer absorb the growing number of migrants from other places, there has been increased interest in the urban to rural population redistribution. This reverse migration also has come about due to slower rates of employment growth in the urban centers and improved economic opportunities

  13. A Population of Assessment Tasks

    Science.gov (United States)

    Daro, Phil; Burkhardt, Hugh

    2012-01-01

    We propose the development of a "population" of high-quality assessment tasks that cover the performance goals set out in the "Common Core State Standards for Mathematics." The population will be published. Tests are drawn from this population as a structured random sample guided by a "balancing algorithm."

  14. Population Parameters of Beaked Whales

    Science.gov (United States)

    2012-09-30

    of deep diving cetaceans , their use of the habitat, and their sensitivity to human interactions . The results will facilitate improved regional...augment the sparse knowledge of beaked whale population biology, facilitating the assessment of possible population effects of human impacts...potential population effects of human impacts. Economic development Economic development is often related to increasing noise levels in the ocean

  15. Population Education Documents, Reprint Series.

    Science.gov (United States)

    United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and Oceania.

    This publication contains reprints of five documents that were either published in foreign journals or released in limited numbers by author or publisher. The papers are all concerned with population education, but deal more specifically with the role of population and the schools. Among the topics discussed are population education and the school…

  16. Grafting and Paladin Pic-21 for Nematode and Weed Management in Vegetable Production

    Science.gov (United States)

    Kokalis-Burelle, Nancy; Butler, David M.; Hong, Jason C.; Bausher, Michael G.; McCollum, Greg; Rosskopf, Erin N.

    2016-01-01

    Two years of field trials conducted in a Meloidogyne incognita-infested field evaluated grafting and Paladin Pic-21 (dimethyl disulfide:chloropicrin [DMDS:Pic] 79:21) for root-knot nematode and weed control in tomato and melon. Tomato rootstocks evaluated were; ‘TX301’, ‘Multifort’, and ‘Aloha’. ‘Florida 47’ was the scion and the nongrafted control. A double crop of melon was planted into existing beds following tomato harvest. Melon rootstocks, C. metulifer and ‘Tetsukabuto’, were evaluated with nongrafted ‘Athena’ in year 1. In year 2, watermelon followed tomato with scion variety ‘Tri-X Palomar’ as the control and also grafted onto ‘Emphasis’ and ‘Strongtosa’ rootstocks. Four soil treatments were applied in fall both years under Canslit metalized film; Paladin Pic-21, methyl bromide:chloropicrin (MeBr:C33, 67:33), Midas (iodomethane:chloropicrin 50:50), and a herbicide-treated control. M. incognita J2 in soil were highest in herbicide control plots and nongrafted tomato. All soil treatments produced similar tomato growth, which was greater than the herbicide control. All treatments reduced M. incognita J2 in roots compared to the herbicide control. ‘Multifort’ rootstock produced the largest and healthiest roots; however, the number of M. incognita isolated from roots did not differ among the tomato rootstocks tested. Galling on tomato was highest in herbicide control plots and nongrafted plants. In melon, M. incognita J2 in soil did not differ among melon rootstocks, but numbers isolated from melon rootstocks increased in ‘Tetsukabuto’ compared with C. metuliferus. ‘Tetsukabuto’ were larger root systems than nongrafted ‘Athena’. All fumigants provided protection for all melon rootstocks against galling by M. incognita compared to the herbicide control. Galling on C. metuliferus rootstock was less in all fumigant treatments compared with nongrafted ‘Athena’ and ‘Tetsukabuto’. In watermelon, M. incognita

  17. Grafting and Paladin Pic-21 for Nematode and Weed Management in Vegetable Production.

    Science.gov (United States)

    Kokalis-Burelle, Nancy; Butler, David M; Hong, Jason C; Bausher, Michael G; McCollum, Greg; Rosskopf, Erin N

    2016-12-01

    Two years of field trials conducted in a Meloidogyne incognita-infested field evaluated grafting and Paladin Pic-21 (dimethyl disulfide:chloropicrin [DMDS:Pic] 79:21) for root-knot nematode and weed control in tomato and melon. Tomato rootstocks evaluated were; 'TX301', 'Multifort', and 'Aloha'. 'Florida 47' was the scion and the nongrafted control. A double crop of melon was planted into existing beds following tomato harvest. Melon rootstocks, C. metulifer and 'Tetsukabuto', were evaluated with nongrafted 'Athena' in year 1. In year 2, watermelon followed tomato with scion variety 'Tri-X Palomar' as the control and also grafted onto 'Emphasis' and 'Strongtosa' rootstocks. Four soil treatments were applied in fall both years under Canslit metalized film; Paladin Pic-21, methyl bromide:chloropicrin (MeBr:C33, 67:33), Midas (iodomethane:chloropicrin 50:50), and a herbicide-treated control. M. incognita J2 in soil were highest in herbicide control plots and nongrafted tomato. All soil treatments produced similar tomato growth, which was greater than the herbicide control. All treatments reduced M. incognita J2 in roots compared to the herbicide control. 'Multifort' rootstock produced the largest and healthiest roots; however, the number of M. incognita isolated from roots did not differ among the tomato rootstocks tested. Galling on tomato was highest in herbicide control plots and nongrafted plants. In melon, M. incognita J2 in soil did not differ among melon rootstocks, but numbers isolated from melon rootstocks increased in 'Tetsukabuto' compared with C. metuliferus. 'Tetsukabuto' were larger root systems than nongrafted 'Athena'. All fumigants provided protection for all melon rootstocks against galling by M. incognita compared to the herbicide control. Galling on C. metuliferus rootstock was less in all fumigant treatments compared with nongrafted 'Athena' and 'Tetsukabuto'. In watermelon, M. incognita in soil and roots did not differ among soil treatments or

  18. Stochastic population theories

    CERN Document Server

    Ludwig, Donald

    1974-01-01

    These notes serve as an introduction to stochastic theories which are useful in population biology; they are based on a course given at the Courant Institute, New York, in the Spring of 1974. In order to make the material. accessible to a wide audience, it is assumed that the reader has only a slight acquaintance with probability theory and differential equations. The more sophisticated topics, such as the qualitative behavior of nonlinear models, are approached through a succession of simpler problems. Emphasis is placed upon intuitive interpretations, rather than upon formal proofs. In most cases, the reader is referred elsewhere for a rigorous development. On the other hand, an attempt has been made to treat simple, useful models in some detail. Thus these notes complement the existing mathematical literature, and there appears to be little duplication of existing works. The authors are indebted to Miss Jeanette Figueroa for her beautiful and speedy typing of this work. The research was supported by the Na...

  19. Population and health.

    Science.gov (United States)

    Kwon, E H

    1975-01-01

    Quality of population is as important as quantity when one is discussing public health needs or quality of the labor force. Population quality as measured by physical disease, mental disease, maternal death and morbidity rates, fetal and infant mortality rates, and family size and child health is discussed. Charts give figures for Korea from a variety of sample surveys and census studies for 1973. All developing countries have high child death rates from communicable diseases. Korea, in addition, suffers from several parasitic diseases. The problems of maternal death and morbidity are due to disease, hard physical labor during pregnancy, poorly attended births (26% were attended by a mother or mother-in-law and 11% by friends and relatives), and high parity. Figures show that the danger of childbirth is greatest for the 1st baby, lower for the 2nd and 3rd, then rises, climbing steeply after the 5th birth. Iron deficiency anemia and oxalic acid deficiency together with general malnutrition contribute to high maternal morbidity and mortality and fetal death or improper brain development. It is also well accepted that children from large families have slower physical and mental growth than children in smaller families. Family planning problems can best be solved by integrating birth spacing and birth limitation programs into a total maternal and child health scheme and emphasizing the health aspects of family planning. Maternity-centered family planning is but 1 example of such an integrated approach. This integration will make better use of personnel, result in better program supervision, and will help the mother understand it is in her best interest to practice family planning.

  20. Seleção para resistência de genótipos de cenoura aos nematóides-das-galhas Selection for carrot genotypes resistance to root-knot nematodes in field and greenhouse

    Directory of Open Access Journals (Sweden)

    Giovani O da Silva

    2011-09-01

    identify for which ones it is possible to differentiate among genotypes and to verify the possibility of evaluation only in one environment or the elimination of characters with high correlation. Thirty eight and thirty one families from the carrot populations '0812518' and '0812519', and the cultivars Brasília and Kuronan as tolerant and susceptible standards, respectively, were evaluated. In a field whose soil was naturally infected by a mix of Meloidogyne incognita race 1 and Meloidogyne javanica, the selection to resistance to root-knot nematode was based on lower percentage of infection in the root, of the major genotypes of carrot production in t/ha and reproduction factor; and in greenhouse, to each one of the same nematode species and too for a mix of both, was evaluated the index of gall and index of egg mass. There is no possibility of selection in only one condition or the elimination of some characters, indicating that, to obtain more yielding and more tolerant cultivars, the combined selection in the various characters and environments are necessary. In the field experiment, it was only possible to differentiate the genotypes for root yield. In the greenhouse, it was possible to identify superior genotypes for all characters tested. However, the average population was not better than the 'Brasilia' standard that originated these populations. This result confirms the necessity to search for more efficient methods of selection.

  1. Biochemical changes in grape rootstocks resulted from humic acid treatments in relation to nematode infection

    Institute of Scientific and Technical Information of China (English)

    Hosny H Kesba; Hossam S El-Beltagi

    2012-01-01

    Objective: To investigate the effect of humic acid on nematode infected, resistant and susceptible grapes in relation to lipid peroxidation and antioxidant mechanisms on selected biochemical parameters known as proactive substances. Methods: The grape rootstocks, superior, superior/freedom and freedom were reacted differently to Meloidogyne incognita and Rotylenchulus reniformis according to rootstock progenitor. Two weeks after inoculation, two commercial products of humic acid were applied at the rate of (2, 4 mL or grams/plant) as soil drench. After 4 months, nematode soil populations were extracted and counted. A subsample of roots from each plant was stained and gall numbers, embedded stages per root were calculated, final population, nematode build up (Pf/Pi), average of eggs/eggmass were estimated. Subsamples of fresh root of each treatment were chemically analyzed. Results: Freedom reduced significantly the nematode criteria and build up. Humic acid granules appeared to be more suppressive to nematode build up on superior and the higher dose on superior/freedom than liquid treatments. On freedom, all treatments reduced significantly the nematode build up regardless to the material nature. The higher dose was more effective than the lower one. As a result of humic acid applications, the malondialdehyde (MDA) and H2O2 contents were significantly reduced after humic acid treatments while the antioxidant compounds glutathione (GSH), ascorbic acid (ASA) and total phenol contents were significantly increased when compared with check. Antioxidant defense enzymes ascorbate peroxidase (APX), superoxide dismutase (SOD), catalase (CAT) and polyphenol oxidase (PPO) showed significant increase in their specific activities in treated plants compared with nematode treated check. Conclusions: Humic acid treatments improve the yield of grape by increasing the contents of antioxidant compounds and the specific activities of antioxidant enzymes.

  2. Population and the World Bank.

    Science.gov (United States)

    Sankaran, S

    1973-12-01

    The World Bank Group regards excessive population growth as the single greatest obstacle to economic and social advance in the underdeveloped world. Since 1969 the Bank and the International Development Agency have provided countries with technical assistance through education, fact-finding, and analysis and given 65.7 million dollars for population projects. These projects, in India, Indonesia, Iran, Jamaica, and Malaysia provide training centers, population education, research, and evaluation as well as actual construction of clinics and mobile units. Because population planning touches sensitive areas of religion, caste, race, morality, and politics, the involved nation's political commitment to plan population growth is critical to the success of any program.

  3. Stellar populations in star clusters

    CERN Document Server

    Li, Chengyuan; Deng, Licai

    2016-01-01

    Stellar populations contain the most important information about star clus- ter formation and evolution. Until several decades ago, star clusters were believed to be ideal laboratories for studies of simple stellar populations (SSPs). However, discoveries of multiple stellar populations in Galactic globular clusters have expanded our view on stellar populations in star clusters. They have simultaneously generated a number of controversies, particularly as to whether young star clusters may have the same origin as old globular clusters. In addition, extensive studies have revealed that the SSP scenario does not seem to hold for some intermediate-age and young star clusters either, thus making the origin of multiple stellar populations in star clusters even more complicated. Stellar population anomalies in numerous star clusters are well-documented, implying that the notion of star clusters as true SSPs faces serious challenges. In this review, we focus on stellar populations in massive clusters with different ...

  4. Population Health and Occupational Therapy.

    Science.gov (United States)

    Braveman, Brent

    2016-01-01

    Occupational therapy practitioners play an important role in improving the health of populations through the development of occupational therapy interventions at the population level and through advocacy to address occupational participation and the multiple determinants of health. This article defines and explores population health as a concept and describes the appropriateness of occupational therapy practice in population health. Support of population health practice as evidenced in the official documents of the American Occupational Therapy Association and the relevance of population health for occupational therapy as a profession are reviewed. Recommendations and directions for the future are included related to celebration of the achievements of occupational therapy practitioners in the area of population health, changes to the Occupational Therapy Practice Framework and educational accreditation standards, and the importance of supporting, recognizing, rewarding, and valuing occupational therapy practitioners who assume roles in which direct care is not their primary function.

  5. Language dynamics in finite populations.

    Science.gov (United States)

    Komarova, Natalia L; Nowak, Martin A

    2003-04-01

    Any mechanism of language acquisition can only learn a restricted set of grammars. The human brain contains a mechanism for language acquisition which can learn a restricted set of grammars. The theory of this restricted set is universal grammar (UG). UG has to be sufficiently specific to induce linguistic coherence in a population. This phenomenon is known as "coherence threshold". Previously, we have calculated the coherence threshold for deterministic dynamics and infinitely large populations. Here, we extend the framework to stochastic processes and finite populations. If there is selection for communicative function (selective language dynamics), then the analytic results for infinite populations are excellent approximations for finite populations; as expected, finite populations need a slightly higher accuracy of language acquisition to maintain coherence. If there is no selection for communicative function (neutral language dynamics), then linguistic coherence is only possible for finite populations.

  6. European population substructure: clustering of northern and southern populations.

    Directory of Open Access Journals (Sweden)

    Michael F Seldin

    2006-09-01

    Full Text Available Using a genome-wide single nucleotide polymorphism (SNP panel, we observed population structure in a diverse group of Europeans and European Americans. Under a variety of conditions and tests, there is a consistent and reproducible distinction between "northern" and "southern" European population groups: most individual participants with southern European ancestry (Italian, Spanish, Portuguese, and Greek have >85% membership in the "southern" population; and most northern, western, eastern, and central Europeans have >90% in the "northern" population group. Ashkenazi Jewish as well as Sephardic Jewish origin also showed >85% membership in the "southern" population, consistent with a later Mediterranean origin of these ethnic groups. Based on this work, we have developed a core set of informative SNP markers that can control for this partition in European population structure in a variety of clinical and genetic studies.

  7. Population distribution and population growth in Yogyakarta special region

    Directory of Open Access Journals (Sweden)

    Ida Bagus Mantra

    2013-07-01

    The annual rate of population growth in Yogyakarta Special Region is much lower compared with other provinces in Java. During 1961 and 1971 the rate of population growth was 1.1 percent, for the period 1971— 1980 became 1.09 percent. This region experienced a net loss of population through migration, and that the losses were greater in the poor areas of Gunung Kidul and Kulon Progo

  8. A population genetics model of linkage disequilibrium in admixed populations

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Understanding linkage disequilibrium (LD) created in admixed population and the rate of decay in the disequilibrium over evolution is an important subject in population genetics theory and in disease gene mapping in human populations. The present study represents the theoretical investigation of effects of gene frequencies, levels of LD and admixture proportions of donor populations on the evolutionary dynamics of the LD of the admixed population. We examined the conditions under which the admixed population reached linkage equilibrium or the peak level of the LD. The study reveals the inappropriateness in approximating the dynamics of the LD generated by population admixture by the commonly used formula in literature. An appropriate equation for the dynamics is proposed. The distinct feature of the newly suggested formula is that the value of the nonlinear component of the LD remains constant in the first generation of the population evolution. Comparison between the predicted disequilibrium dynamics shows that the error will be caused by using the old formula, and thus resulting in a misguidance in using the evolutionary information of the admixed population in gene mapping.

  9. Bacterial antagonists of fungal pathogens also control root-knot nematodes by induced systemic resistance of tomato plants.

    Science.gov (United States)

    Adam, Mohamed; Heuer, Holger; Hallmann, Johannes

    2014-01-01

    The potential of bacterial antagonists of fungal pathogens to control the root-knot nematode Meloidogyne incognita was investigated under greenhouse conditions. Treatment of tomato seeds with several strains significantly reduced the numbers of galls and egg masses compared with the untreated control. Best performed Bacillus subtilis isolates Sb4-23, Mc5-Re2, and Mc2-Re2, which were further studied for their mode of action with regard to direct effects by bacterial metabolites or repellents, and plant mediated effects. Drenching of soil with culture supernatants significantly reduced the number of egg masses produced by M. incognita on tomato by up to 62% compared to the control without culture supernatant. Repellence of juveniles by the antagonists was shown in a linked twin-pot set-up, where a majority of juveniles penetrated roots on the side without inoculated antagonists. All tested biocontrol strains induced systemic resistance against M. incognita in tomato, as revealed in a split-root system where the bacteria and the nematodes were inoculated at spatially separated roots of the same plant. This reduced the production of egg masses by up to 51%, while inoculation of bacteria and nematodes in the same pot had only a minor additive effect on suppression of M. incognita compared to induced systemic resistance alone. Therefore, the plant mediated effect was the major reason for antagonism rather than direct mechanisms. In conclusion, the bacteria known for their antagonistic potential against fungal pathogens also suppressed M. incognita. Such "multi-purpose" bacteria might provide new options for control strategies, especially with respect to nematode-fungus disease complexes that cause synergistic yield losses.

  10. Bacterial antagonists of fungal pathogens also control root-knot nematodes by induced systemic resistance of tomato plants.

    Directory of Open Access Journals (Sweden)

    Mohamed Adam

    Full Text Available The potential of bacterial antagonists of fungal pathogens to control the root-knot nematode Meloidogyne incognita was investigated under greenhouse conditions. Treatment of tomato seeds with several strains significantly reduced the numbers of galls and egg masses compared with the untreated control. Best performed Bacillus subtilis isolates Sb4-23, Mc5-Re2, and Mc2-Re2, which were further studied for their mode of action with regard to direct effects by bacterial metabolites or repellents, and plant mediated effects. Drenching of soil with culture supernatants significantly reduced the number of egg masses produced by M. incognita on tomato by up to 62% compared to the control without culture supernatant. Repellence of juveniles by the antagonists was shown in a linked twin-pot set-up, where a majority of juveniles penetrated roots on the side without inoculated antagonists. All tested biocontrol strains induced systemic resistance against M. incognita in tomato, as revealed in a split-root system where the bacteria and the nematodes were inoculated at spatially separated roots of the same plant. This reduced the production of egg masses by up to 51%, while inoculation of bacteria and nematodes in the same pot had only a minor additive effect on suppression of M. incognita compared to induced systemic resistance alone. Therefore, the plant mediated effect was the major reason for antagonism rather than direct mechanisms. In conclusion, the bacteria known for their antagonistic potential against fungal pathogens also suppressed M. incognita. Such "multi-purpose" bacteria might provide new options for control strategies, especially with respect to nematode-fungus disease complexes that cause synergistic yield losses.

  11. Fitonematoides associados a frutíferas na região Noroeste do Paraná, Brasil Plant parasitic nematodes associated with fruit crops in the Northwest of Paraná, Brazil

    Directory of Open Access Journals (Sweden)

    Cláudia Regina Dias-Arieira

    2010-12-01

    Full Text Available Com o objetivo de estudar a ocorrência de nematoides fitoparasitos em frutíferas cultivadas na região noroeste do Paraná, realizou-se um levantamento, envolvendo 124 amostras de solo e raízes coletadas de 19 espécies de frutíferas, em 15 municípios, no período de dezembro/2007 a fevereiro/2009. As amostras foram submetidas a extrações e avaliadas sob microscópio óptico. Foram constatados nove diferentes gêneros de nematoides. Em citros, a espécie mais frequente e abundante foi Tylenchulus semipenetrans, sendo também recuperados das amostras os gêneros Meloidogyne, Pratylenchus, Helicotylenchus, Xiphinema, Trichodorus, Mesocriconema e Dolichodorus. Nas demais frutíferas, os gêneros observados foram Meloidogyne, Pratylenchus, Helicotylenchus e Hemicycliophora. A maior abundância de Pratylenchus brachyurus ocorreu em abacaxizeiro, Meloidogyne incognita em figueira e caquizeiro, e Helicotylenchus dihystera e H. multicinctus em bananeira. Os principais gêneros de fitonematoides foram constatados em aproximadamente 50% das amostras, podendo representar risco para fruteiras da região se não manejados adequadamente.A survey was carried out in order to study the occurrence of plant parasitic nematodes in fruit crops in the Northwest of Paraná, from December 2007 to February 2009. A hundred and twenty four soil and roots samples were collected from 19 species of fruit crops in 15 different municipalities. Nematodes were extracted from the samples and identified under an optical microscope. Nine genera of plant parasitic nematodes were found. In citrus, the most abundant species was Tylenchulus semipenetrans, but it was also recovered Meloidogyne, Pratylenchus, Helicotylenchus, Xiphinema, Trichodorus, Mesocriconema and Dolichodorus. In the other fruit crops, Meloidogyne, Pratylenchus, Helicotylenchus and Hemicycliophora were recovered. Pratylenchus brachyurus was most abundant in pineapple crops, Meloidogyne incognita in fig and

  12. population in Slovakia

    Directory of Open Access Journals (Sweden)

    Dravecký Miroslav

    2015-06-01

    Full Text Available V rokoch 2011 – 2014 sa realizoval monitoring hniezdnej populácie orla krikľavého (Aquila pomarina v ôsmich chránených vtáčích územiach na Slovensku. U 149 hniezdnych párov z celkových 272 úspešných hniezdení počas 4 hniezdnych sezón vyletelo 277 mláďat. Priemerná reprodukčná úspešnosť predstavovala 0,51 juv./prítomný pár, 0,69 juv./hniezdiaci pár a 1,37 juv./100 km2. V uvedenom období bolo okolo hniezd orlov krikľavých ustanovených celkom 151 ochranných zón, ktoré zabezpečili ochranu 119 hniezdnych teritórií, čo predstavuje cca 17 % hniezdnej populácie orla krikľavého na Slovensku. Testovaním účinnosti ochranných zón sa zistilo, že v hniezdach s vyhlásenou ochrannou zónou je vyššia pravdepodobnosť úspešného odchovania mláďat v porovnaní s hniezdami bez takejto zóny. Pravdepodobnosť, že hniezdenie bude úspešné v hniezdach hniezdiacich párov bez ochrannej zóny bola 48.1% (95% confidence intervals (CIs: 37.4–59.0%, v hniezdach s ochrannou zónou 64.8% (95% CIs: 59.8–69.6%. Medzi 5 najčastejšie využívaných hniezdnych stromov na hniezdenie A. pomarina na Slovensku patrí Picea abies 61× (28,4%, Pinus sylvestris 45× (20,9%, Quercus sp. 36× (16,7%, Fagus sylvatica 25× (11,6% a Abies alba 18× (8,4%. Medzi zriedkavejšie druhy hniezdnych stromov patrí Larix decidua 12× (5,6% a Alnus glutinosa 3× (1,4%, ďalších 11 druhov hniezdnych stromov nedosiahli 1 %. Najvyšší počet hniezdnych stromov (n = 215, tj. 34 hniezd (15,8% sa nachádzal v intervale nadmorskej výšky 401 – 450 m a 29 hniezd (13,5% v intervale 351 – 400 m n. m. Ostatné výškové pásma boli pod hranicou 10%. 54% zistených hniezd (116 hniezd sa nachádza vo výškovom pásme 301 – 600 m n. m., 71 hniezd (33% v pásme 600 – 900 m n. m. Najnižšie situované hniezdo bolo v nadmorskej výške 150 m a najvyššie 950 m, priemer bol 595,01 m. Najvyšší počet hniezd (n = 209 bol na strome

  13. Population growth, poverty and health.

    Science.gov (United States)

    Kibirige, J S

    1997-07-01

    One of the most popular explanations for the many problems that face Africa is population growth. Africa's population has doubled since 1960. Africa has the highest fertility rate in the world and the rate of population growth is higher than in any other region. At the same time, Africa faces a social and economic situation that is viewed by many as alarming. Among the problems that devastate Africa is that of persistent poor health. Africa has lower life expectancy, higher mortality rates and is affected by more disease and illness conditions than any other region. Focusing on sub-Saharan Africa, this paper examines the relationship between population growth, poverty and poor health. While most analyses have focused on population growth as an original cause of poverty and underdevelopment, this paper argues that while both population growth and poor health play a significant role in exacerbating the problem of poverty, they are themselves primary consequences of poverty rather than its cause.

  14. Habitat quality and fish population

    OpenAIRE

    Tafesse Tirkaso, Wondmagegn; Gren, Ing-Marie

    2016-01-01

    Degradation of marine ecosystem due to, among others, eutrophication and climate change, has been of concern for sustainable fishery management worldwide, but studies on associated impacts on fish populations are rare. The purpose of this study is to estimate effects of nutrient loads, which cause eutrophication, on the perch population at the Swedish east coast. To this end, we use a modified Gordon-Schaefer logistic growth model for econometric estimation of perch population on the Swedish ...

  15. Screening for Nemaicidal Activity of Some Chinese Plant Extracts against Plant Parasitic Nematodes, Bursaphelenchus xylophilus, Meloidogyne arenaria and Hirschmanniella oryzae%植物抽提物对几种植物病原线虫的杀线活性筛选

    Institute of Scientific and Technical Information of China (English)

    文艳华; 冯志新; 徐汉虹; 陈立

    2001-01-01

    Extracts of 14 Chinese plants (belong to 10 fami lies in Hubei,Shanxi and Guangdong Provinces, China) were assessed f or nematicidal activity against Bursaphelenchus xylophilus using a fungal-f eedin g method in vitro. Some of 14 plant extracts were also assessed for nematicidal activity against Meloidogyne arenaria and Hirschmanniella oryzae. Five p lant ext racts(Cephalotaxus fortunei, Cephalotaxus sinensis, Paeonia suffrutccosa, Soph or a viciifolia and Derris elliptica) showed strong nematicidal activity against B ursaphelenchus xylophilus; 3 plant extracts (Cephalotaxus fortunei, Paeonia suf frutccosa, Sophora viciifolia) also showed strong nematicidal activity agains t M. arenaria and H.oryzae. While 4 plant extracts (Sargentodoxus argota enia, Mang lietia patungensis, Liriope spicata, and Liriodendron chinese) demonstrated no nematicidal activity against B. xylophilus and M. arenaria.%测定了中国湖北、陕西及广东省的10科14种植物抽提物对几种植物病原线虫的杀线活性,结果表明:对松材线虫,毛鱼藤(Derris elliptica)根有极强杀线活性,三尖杉( Cephalotaxus fortunei)茎叶、粗榧(Cephalotaxus sinensis)叶、狼牙刺( Sophora vi ciifolia)种子、紫斑牡丹(Paeonia suffrutccosa)茎有强杀线活性,神农香菊( Dendra nthema indicum)全株有中等杀线活性,瓜叶乌头(Aconitum hemsleyanum)全株、香果树(Emmenopterys henryi)叶、东方荚果蕨(Matteuccia orientalis)茎叶、大叶醉鱼草( Buddleja davidii)叶均无杀线活性;对花生根结线虫及水稻潜根线虫,三尖杉茎叶、狼牙刺种子、紫斑牡丹茎有极强杀线活性,神农香菊全株有中等杀线活性;大血藤(Sargento do xus argotaenia)茎、巴东木莲(Manglietia patungensis)叶、土麦冬(Liriop e spicat a)全株及鹅掌揪(Liriodendron chinese)叶对松材线虫、花生根结线虫均无杀线活性。

  16. [Population control and environment protection].

    Science.gov (United States)

    Qu, G

    1982-01-29

    Although many factors cause environmental pollution and damage, the most important and basic factor is a rapidly increasing population. Therefore, a balanced development of population and environment is essential. The pressure a rapidly increasing populaton exerts on the environment has many aspects. The pressure of population on land resources results in increased land use and increased insecticide use due to increased insect tolerance leading to decreased productivity of cultivated land, increased desert formation, and decreased food supply. Population pressure on forest resources leads to land erosion; one of the major causes of the 1981 flood in Sichuan was attributed to excessive logging activities. Demand for fuels (firewood, straws, animal manures) by an increasing population leads to decrease in natural fertilizers, decreased food production, and energy shortage in rural areas. Population pressure on cities leads to air, water, noise and other environmental pollution as well as decrease in housing facilities and in green vegetation. Problems resulting from population pressures on industrial development include industrial and environmental pollution and unemployment. Population increases and accompanying industrial activities affect the weather which in turn affects the quality of agriculture, forests, and lakes. Thus, if unchecked, atmospheric carbon dioxide level would double by the middle of the next century, which would lead to increase in atmospheric temperature with disastrous consequences. Therefore, a well planned program for population control is essential for achieving decent quality of life.

  17. Population Education: A Critical Population and Development Intervention.

    Science.gov (United States)

    United Nations Population Fund (UNFPA)

    1991-01-01

    This review and assessment of population education programs demonstrates that, although population education has made many contributions to the overall education process, its success requires continual revision and review of existing conceptualizations and content. Outlines and discusses other critical factors, pertinent issues, and guidelines for…

  18. Population dynamics and population control of Galium aparine L.

    NARCIS (Netherlands)

    Weide, van der R.Y.

    1993-01-01

    The population biology of Galium aparine L. needs to be better understood, in order to be able to rationalize decisions about the short- and long-term control of this weed species for different cropping practices.A population dynamics model was developed to simulate the basic processes of the life c

  19. Detection, Diversity, and Population Dynamics of Waterborne Phytophthora ramorum Populations.

    Science.gov (United States)

    Eyre, C A; Garbelotto, M

    2015-01-01

    Sudden oak death, the tree disease caused by Phytophthora ramorum, has significant environmental and economic impacts on natural forests on the U.S. west coast, plantations in the United Kingdom, and in the worldwide nursery trade. Stream baiting is vital for monitoring and early detection of the pathogen in high-risk areas and is performed routinely; however, little is known about the nature of water-borne P. ramorum populations. Two drainages in an infested California forest were monitored intensively using stream-baiting for 2 years between 2009 and 2011. Pathogen presence was determined both by isolation and polymerase chain reaction (PCR) from symptomatic bait leaves. Isolates were analyzed using simple sequence repeats to study population dynamics and genetic structure through time. Isolation was successful primarily only during spring conditions, while PCR extended the period of pathogen detection to most of the year. Water populations were extremely diverse, and changed between seasons and years. A few abundant genotypes dominated the water during conditions considered optimal for aerial populations, and matched those dominant in aerial populations. Temporal patterns of genotypic diversification and evenness were identical among aerial, soil, and water populations, indicating that all three substrates are part of the same epidemiological cycle, strongly influenced by rainfall and sporulation on leaves. However, there was structuring between substrates, likely arising due to reduced selection pressure in the water. Additionally, water populations showed wholesale mixing of genotypes without the evident spatial autocorrelation present in leaf and soil populations.

  20. Matrix population models from 20 studies of perennial plant populations

    Science.gov (United States)

    Ellis, Martha M.; Williams, Jennifer L.; Lesica, Peter; Bell, Timothy J.; Bierzychudek, Paulette; Bowles, Marlin; Crone, Elizabeth E.; Doak, Daniel F.; Ehrlen, Johan; Ellis-Adam, Albertine; McEachern, Kathryn; Ganesan, Rengaian; Latham, Penelope; Luijten, Sheila; Kaye, Thomas N.; Knight, Tiffany M.; Menges, Eric S.; Morris, William F.; den Nijs, Hans; Oostermeijer, Gerard; Quintana-Ascencio, Pedro F.; Shelly, J. Stephen; Stanley, Amanda; Thorpe, Andrea; Tamara, Ticktin; Valverde, Teresa; Weekley, Carl W.

    2012-01-01

    Demographic transition matrices are one of the most commonly applied population models for both basic and applied ecological research. The relatively simple framework of these models and simple, easily interpretable summary statistics they produce have prompted the wide use of these models across an exceptionally broad range of taxa. Here, we provide annual transition matrices and observed stage structures/population sizes for 20 perennial plant species which have been the focal species for long-term demographic monitoring. These data were assembled as part of the 'Testing Matrix Models' working group through the National Center for Ecological Analysis and Synthesis (NCEAS). In sum, these data represent 82 populations with >460 total population-years of data. It is our hope that making these data available will help promote and improve our ability to monitor and understand plant population dynamics.