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Sample records for curl mite resistance

  1. Impact of Wheat streak mosaic virus and Triticum mosaic virus co-infection of wheat on transmission rates by wheat curl mites

    Science.gov (United States)

    Wheat streak mosaic virus (WSMV) and Triticum mosaic virus (TriMV) are transmitted by the wheat curl mite (WCM, Aceria tosichella Keifer). Previous work has shown that different mite genotypes transmit TriMV at different rates. The objective of this research was to determine if mite genotypes differ...

  2. Spatial and host-associated variation in prevalence and population density of wheat curl mite (Aceria tosichella) cryptic genotypes in agricultural landscapes.

    Science.gov (United States)

    The wheat curl mite (WCM), Aceria tosichella Keifer, is a major pest of cereals worldwide that also comprises a complex of at least 16 genetic lineages with divergent physiological traits, including host preference and specificity. The goal of this study was to test the extent to which host-plant sp...

  3. Breeding the Mite-Resistant Honeybee by Nutritional Crossbreed Technology

    Institute of Scientific and Technical Information of China (English)

    XIE Xian-bing; PENG Wen-jun; ZENG Zhi-jiang

    2008-01-01

    Mite (Varroa destructor) is one of the most serious parasite threats to the honey bee (Apis mellifera) reared in China. The beekeepers mainly use the drug to control and kill the mite in the past years, but the honey products may be contaminated and the mite is becoming drug-resistant. The main idea of this paper is to research the possibility of mite-resistant honeybee rearing by nutritional crossbreed. The larvae (Apis mellifera ligustica) are bred with the royal jelly of Apis carana carana, and then the morphological index of the worker generation, genotypic frequency and gene frequency of the MDH Ⅱ, genetic resemblance, and mite resistance are measured. The results show that: compared to the parent workers, the proboscis length, anterior wing area, the total length of the third and fourth dorsal plate of the abdomen, the length of the fourth dorsal plate of the tuberculum, the area of the sixth abdominal segment, and the area of wax mirrors are significantly different, but the differences in the brachium index, dactylus index, and wing claw are not significant. Moreover, there are some mutations in the genotypic frequency and gene frequency of the MDH Ⅱ. The mite resistance of the nutritional crossbreed worker is significantly higher. The morphological, physical, and biochemical characters, genetic resemblance, and the mite-resistant ability of the worker generation can be changed by nutritional crossbreeding. Nutritional crossbreeding can be a new way to breed the honeybee.

  4. Exploitation of Solanum chilense and Solanum peruvianum in tomato breeding for resistance to Tomato yellow leaf curl disease.

    OpenAIRE

    Julián Rodríguez, Olga

    2014-01-01

    Among viral diseases affecting cultivated tomato, Tomato yellow leaf curl disease (TYLCD) is one of the most devastating. This disease is caused by a complex of viruses of which Tomato yellow leaf curl virus (TYLCV) is regarded as the most important species. Current control strategies to fight viral diseases in tomato are mainly based on genetic resistance derived from wild relatives. In the present thesis, resistance derived from S. chilense and S. peruvianum has been exploited in breeding f...

  5. Fine mapping of the tomato yellow leaf curl virus resistance gene Ty-2 on chromosome 11 of tomato

    NARCIS (Netherlands)

    Yang, X.; Caro Rios, C.M.; Hutton, S.F.; Scott, J.W.; Guo, Y.; Wang, Xiaoxuan; Rashid, H.; Szinay, D.; Jong, de J.H.S.G.M.; Visser, R.G.F.; Bai, Y.; Du, Y.

    2014-01-01

    Resistances to begomoviruses, including bipartite tomato mottle virus and monopartite tomato yellow leaf curl virus (TYLCV), have been introgressed to cultivated tomato (Solanumlycopersicum) fromwild tomato accessions. A major gene, Ty-2 from S. habrochaites f. glabratum accession ‘‘B6013,’’ that

  6. Fine mapping of the tomato yellow leaf curl virus resistance gene Ty-2 on chromosome 11 of tomato

    OpenAIRE

    Yang, X.; Caro Rios, C.M.; Hutton, S.F.; Scott, J. W.; Guo, Y.; Wang, Xiaoxuan; Rashid, H.; Szinay, D.; de Jong; Visser, R.G.F.; Bai, Y.; Du, Y.

    2014-01-01

    Resistances to begomoviruses, including bipartite tomato mottle virus and monopartite tomato yellow leaf curl virus (TYLCV), have been introgressed to cultivated tomato (Solanum lycopersicum) from wild tomato accessions. A major gene, Ty-2 from S. habrochaites f. glabratum accession “B6013,” that confers resistance to TYLCV was previously mapped to a 19-cM region on the long arm of chromosome 11. In the present study, approximately 11,000 plants were screened and nearly 157 recombination even...

  7. Differential water mite parasitism, phenoloxidase activity, and resistance to mites are unrelated across pairs of related damselfly species.

    Directory of Open Access Journals (Sweden)

    Julia J Mlynarek

    Full Text Available Related host species often demonstrate differences in prevalence and/or intensity of infection by particular parasite species, as well as different levels of resistance to those parasites. The mechanisms underlying this interspecific variation in parasitism and resistance expression are not well understood. Surprisingly, few researchers have assessed relations between actual levels of parasitism and resistance to parasites seen in nature across multiple host species. The main goal of this study was to determine whether interspecific variation in resistance against ectoparasitic larval water mites either was predictive of interspecific variation in parasitism for ten closely related species of damselflies (grouped into five "species pairs", or was predicted by interspecific variation in a commonly used measure of innate immunity (total Phenoloxidase or potential PO activity. Two of five species pairs had interspecific differences in proportions of individuals resisting larval Arrenurus water mites, only one of five species pairs had species differences in prevalence of larval Arrenurus water mites, and another two of five species pairs showed species differences in mean PO activity. Within the two species pairs where species differed in proportion of individuals resisting mites the species with the higher proportion did not have correspondingly higher PO activity levels. Furthermore, the proportion of individuals resisting mites mirrored prevalence of parasitism in only one species pair. There was no interspecific variation in median intensity of mite infestation within any species pair. We conclude that a species' relative ability to resist particular parasites does not explain interspecific variation in parasitism within species pairs and that neither resistance nor parasitism is reflected by interspecific variation in total PO or potential PO activity.

  8. Intermediate Levels of Resistance to Tracheal Mites in Crosses Between Resistant and Susceptible Strains

    Science.gov (United States)

    Bioassays and sampling of field colonies were used to test the hypothesis that the resistance to tracheal mites in Russian honey bees is a dominant trait. Earlier studies with Buckfast bees as a resistant parent had suggested dominance or partial dominance in their crosses with either a Canadian su...

  9. Molecular dissection of Tomato leaf curl virus resistance in tomato line TY172 derived from Solanum peruvianum.

    Science.gov (United States)

    Anbinder, Ilana; Reuveni, Moshe; Azari, Raviv; Paran, Ilan; Nahon, Sahadia; Shlomo, Haviva; Chen, Lea; Lapidot, Moshe; Levin, Ilan

    2009-08-01

    Tomato yellow leaf curl virus (TYLCV) is devastating to tomato (Solanum lycopersicum) crops and resistant cultivars are highly effective in controlling the disease. The breeding line TY172, originating from Solanum peruvianum, is highly resistant to TYLCV. To map quantitative trait loci (QTLs) controlling TYLCV resistance in TY172, appropriate segregating populations were analyzed using 69 polymorphic DNA markers spanning the entire tomato genome. Results show that TYLCV resistance in TY172 is controlled by a previously unknown major QTL, originating from the resistant line, and four additional minor QTLs. The major QTL, we term Ty-5, maps to chromosome 4 and accounts for 39.7-46.6% of the variation in symptom severity among segregating plants (LOD score 33-35). The minor QTLs, originated either from the resistant or susceptible parents, were mapped to chromosomes 1, 7, 9 and 11, and contributed 12% to the variation in symptom severity in addition to Ty-5.

  10. Recessive Resistance Derived from Tomato cv. Tyking-Limits Drastically the Spread of Tomato Yellow Leaf Curl Virus

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    Rita C. Pereira-Carvalho

    2015-05-01

    Full Text Available The tomato yellow leaf curl disease (TYLCD causes severe damage to tomato (Solanum lycopersicum L. crops throughout tropical and subtropical regions of the world. TYLCD is associated with a complex of single-stranded circular DNA plant viruses of the genus Begomovirus (family Geminiviridae transmitted by the whitefy Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae. The tomato inbred line TX 468-RG is a source of monogenic recessive resistance to begomoviruses derived from the hybrid cv. Tyking F1. A detailed analysis of this germplasm source against tomato yellow leaf curl virus-Israel (TYLCV-IL, a widespread TYLCD-associated virus, showed a significant restriction to systemic virus accumulation even under continuous virus supply. The resistance was effective in limiting the onset of TYLCV-IL in tomato, as significantly lower primary spread of the virus occurred in resistant plants. Also, even if a limited number of resistant plants could result infected, they were less efficient virus sources for secondary spread owing to the impaired TYLCV-IL accumulation. Therefore, the incorporation of this resistance into breeding programs might help TYLCD management by drastically limiting TYLCV-IL spread.

  11. Resistance phenomena to amitraz from populations of the ectoparasitic mite Varroa destructor of Argentina.

    Science.gov (United States)

    Maggi, Matías D; Ruffinengo, Sergio R; Negri, Pedro; Eguaras, Martín J

    2010-10-01

    In Argentina, Varroa destructor resistance to coumaphos has been previously reported. However, the status of mite susceptibility to other hard acaricides is still unknown. At present, high infestation levels of V. destructor are being detected in colonies of Apis mellifera after treatment with amitraz. The aim of the present study was to determine the LC(50) of amitraz in V. destructor from three apiaries with high mite density after treatment with the acaricide. The LC(50) values were 3.9, 3.5, and 3.7 μg/Petri dish for mites from three different apiaries. Significant LC(50) differences were detected between resistant and susceptible mites. LC(50) increased 35-39-fold when compared to the corresponding baseline, suggesting the development of resistance. These results are the first report of resistance to amitraz in V. destructor in Argentina and extend the knowledge according to the status of acaricides resistance in the country.

  12. Comparative proteomic analysis reveals mite (Varroa destructor) resistance-related proteins in Eastern honeybees (Apis cerana).

    Science.gov (United States)

    Ji, T; Shen, F; Liu, Z; Yin, L; Shen, J; Liang, Q; Luo, Y X

    2015-08-21

    The mite (Varroa destructor) has become the greatest threat to apiculture worldwide. As the original host of the mite, Apis cerana can effectively resist the mite. An increased understanding of the resistance mechanisms of Eastern honeybees against V. destructor may help researchers to protect other species against these parasites. In this study, the proteomes of 4 Apis cerana colonies were analyzed using an isobaric tag for relative and absolute quantitation technology. We determined the differences in gene and protein expression between susceptible and resistant colonies that were either unchallenged or challenged by V. destructor. The results showed that a total of 1532 proteins were identified. Gene Ontology enrichment analysis suggested that the transcription factors and basic metabolic and respiratory processes were efficient and feasible factors controlling this resistance, and 12 differentially expressed proteins were identified in Venn analysis. The results were validated by quantitative polymerase chain reaction. This study may provide insight into the genetic mechanisms underlying the resistance of honeybee to mites.

  13. Transcriptome profiling to discover defense-related genes associated with resistance line ty-5 against Tomato yellow leaf curl virus in tomato

    Science.gov (United States)

    Tomato yellow leaf curl virus (TYLCV), a whitefly-transmitted begomovirus, has caused serious economic losses to tomato crops in the U.S. and around the world. The most effective management would be the use of a TYLCV-resistant tomato cultivar. Several sources of TYLCV resistance genes have been ide...

  14. Host plant resistance among tomato accessions to the spider mite Tetranychus evansi in Kenya.

    Science.gov (United States)

    Onyambus, G K; Maranga, R O; Gitonga, L M; Knapp, M

    2011-08-01

    The spider mite Tetranychus evansi has a broad range of host plants. Control of T. evansi has been a big challenge to tomato farmers due to its fast rate of reproduction, development of resistance to chemical pesticides and its ability to use weeds as alternative hosts when the tomato plants are not available. The aim of the current study was to determine the host plant acceptance and the relative contributions of trichomes in the control of the red spider mite by comparing the survival, development and oviposition rates of the red spider mite on eight tomato accessions. Leaflets from eight tomato varieties were assayed with the spider mites to determine the egg laying capacity and developmental time of the spider mites on the tomato accessions as well as the trichome densities. Densities of trichome types I, IV, V and VI varied among the tomato accessions. Variation in types I, IV and VI accounted for most of the variation in mite responses. The varieties with high densities of types IV and VI had the highest fecundity and mite development did not go beyond the larval stage. The developmental time varied significantly among the tomato accessions. The results indicated that the higher the density of trichome type I the lower the adult survival. The findings indicated possible resistance of some of the tested tomato accessions against T. evansi which is partially associated with trichomes types and density.

  15. A genomic approach to investigate resistance mechanisms in the two-spotted spider mite Tetranychus urticae

    NARCIS (Netherlands)

    Demaeght, P.A.

    2015-01-01

    The two-spotted spider mite (Tetranychus urticae) is a global and important crop pest that is mainly controlled by acaricides. Its rapid development, high fecundity and haplo-diploid reproduction all contribute to the fast development of resistance. Resistance to acaricides can arise due to modifica

  16. Fine mapping of the tomato yellow leaf curl virus resistance gene Ty-2 on chromosome 11 of tomato.

    Science.gov (United States)

    Yang, Xiaohui; Caro, Myluska; Hutton, Samuel F; Scott, John W; Guo, Yanmei; Wang, Xiaoxuan; Rashid, Md Harunur; Szinay, Dora; de Jong, Hans; Visser, Richard G F; Bai, Yuling; Du, Yongchen

    2014-01-01

    Resistances to begomoviruses, including bipartite tomato mottle virus and monopartite tomato yellow leaf curl virus (TYLCV), have been introgressed to cultivated tomato (Solanum lycopersicum) from wild tomato accessions. A major gene, Ty-2 from S. habrochaites f. glabratum accession "B6013," that confers resistance to TYLCV was previously mapped to a 19-cM region on the long arm of chromosome 11. In the present study, approximately 11,000 plants were screened and nearly 157 recombination events were identified between the flanking markers C2_At1g07960 (82.5 cM, physical distance 51.387 Mb) and T0302 (89 cM, 51.878 Mb). Molecular marker analysis of recombinants and TYLCV evaluation of progeny from these recombinants localized Ty-2 to an approximately 300,000-bp interval between markers UP8 (51.344 Mb) and M1 (51.645 Mb). No recombinants were identified between TG36 and C2_At3g52090, a region of at least 115 kb, indicating severe recombination suppression in this region. Due to the small interval, fluorescence in situ hybridization analysis failed to clarify whether recombination suppression is caused by chromosomal rearrangements. Candidate genes predicted based on tomato genome annotation were analyzed by RT-PCR and virus-induced gene silencing. Results indicate that the NBS gene family present in the Ty-2 region is likely not responsible for the Ty-2-conferred resistance and that two candidate genes might play a role in the Ty-2-conferred resistance. Several markers very tightly linked to the Ty-2 locus are presented and useful for marker-assisted selection in breeding programs to introgress Ty-2 for begomovirus resistance.

  17. Field Trial and Molecular Characterization of RNAi-Transgenic Tomato Plants That Exhibit Resistance to Tomato Yellow Leaf Curl Geminivirus.

    Science.gov (United States)

    Fuentes, Alejandro; Carlos, Natacha; Ruiz, Yoslaine; Callard, Danay; Sánchez, Yadira; Ochagavía, María Elena; Seguin, Jonathan; Malpica-López, Nachelli; Hohn, Thomas; Lecca, Maria Rita; Pérez, Rosabel; Doreste, Vivian; Rehrauer, Hubert; Farinelli, Laurent; Pujol, Merardo; Pooggin, Mikhail M

    2016-03-01

    RNA interference (RNAi) is a widely used approach to generate virus-resistant transgenic crops. However, issues of agricultural importance like the long-term durability of RNAi-mediated resistance under field conditions and the potential side effects provoked in the plant by the stable RNAi expression remain poorly investigated. Here, we performed field trials and molecular characterization studies of two homozygous transgenic tomato lines, with different selection markers, expressing an intron-hairpin RNA cognate to the Tomato yellow leaf curl virus (TYLCV) C1 gene. The tested F6 and F4 progenies of the respective kanamycin- and basta-resistant plants exhibited unchanged field resistance to TYLCV and stably expressed the transgene-derived short interfering RNA (siRNAs) to represent 6 to 8% of the total plant small RNAs. This value outnumbered the average percentage of viral siRNAs in the nontransformed plants exposed to TYLCV-infested whiteflies. As a result of the RNAi transgene expression, a common set of up- and downregulated genes was revealed in the transcriptome profile of the plants selected from either of the two transgenic events. A previously unidentified geminivirus causing no symptoms of viral disease was detected in some of the transgenic plants. The novel virus acquired V1 and V2 genes from TYLCV and C1, C2, C3, and C4 genes from a distantly related geminivirus and, thereby, it could evade the repressive sequence-specific action of transgene-derived siRNAs. Our findings shed light on the mechanisms of siRNA-directed antiviral silencing in transgenic plants and highlight the applicability limitations of this technology as it may alter the transcriptional pattern of nontarget genes.

  18. Parallel evolution of cytochrome b mediated bifenazate resistance in the citrus red mite Panonychus citri

    NARCIS (Netherlands)

    Van Leeuwen, T.; Van Nieuwenhuyse, P.; Vanholme, B.; Dermauw, W.; Nauen, R.; Tirry, L.

    2011-01-01

    Bifenazate is a recently developed acaricide that is mainly used to control spider mites on a variety of crops. Although first thought to be a neurotoxin, genetic evidence obtained from bifenazate resistant Tetranychus urticae strains suggested an alternative mode of action as a Qo pocket inhibitor

  19. Monitoring for resistance to organophosphorus and pyrethroid insecticides in varroa mite populations

    Science.gov (United States)

    The occurrence of resistance in Varroa mite populations is a serious threat to the beekeeping industry and crops that rely on the honey bee for pollination. Integrated pest management strategies for control of this pest include the judicious use of insecticides. To monitor field populations of Varro...

  20. Role of cucurbitacin C in resistance to spider mite (Tetranychus urticae) in cucumber (Cucumber sativus L.)

    NARCIS (Netherlands)

    Balkema-Boomstra, A.G.; Zijlstra, S.; Verstappen, F.W.A.; Inggamer, H.; Mercke, P.

    2003-01-01

    Cucurbitacins are bitter triterpenoid compounds that are toxic to most organisms and occur widely in wild and cultivated Cucurbitaceae. The only cucurbitacin identified in Cucumis sativus is cucurbitacin C. The bitter taste of cucumber has been correlated with resistance to the spider mite

  1. Evidence for resistance to carbaryl in poultry red mites from the Republic of Serbia and Montenegro

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    Aleksandar Pavlicevic

    2016-05-01

    Full Text Available The objective of this research was to examine the efficiency of carbaryl under laboratory conditions, based on field populations of poultry red mites from throughout the Republic of Serbia and Montenegro over a period of 6 years (2001-2006. In 2001 samples, an excellent efficiency level of 95.7% at 0.1% carbaryl concentration after 30-minute exposure was found. The total pharmacological profile of carbaryl in relation to D. gallinae mites resulted in adequate control. However, by 2003 a significant decline in carbaryl’s efficiency was apparent. By 2005, a population of D. gallinae was discovered which showed no apparent susceptibility to carbaryl. Poultry red mite populations had by then developed extreme resistance.

  2. The Tomato Yellow Leaf Curl Virus resistance genes Ty-1 and Ty-3 are allelic and code for DFDGD-class RNA-dependent RNA polymerases.

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    Maarten G Verlaan

    2013-03-01

    Full Text Available Tomato Yellow Leaf Curl Virus Disease incited by Tomato yellow leaf curl virus (TYLCV causes huge losses in tomato production worldwide and is caused by different related begomovirus species. Breeding for TYLCV resistance has been based on the introgression of multiple resistance genes originating from several wild tomato species. In this study we have fine-mapped the widely used Solanum chilense-derived Ty-1 and Ty-3 genes by screening nearly 12,000 plants for recombination events and generating recombinant inbred lines. Multiple molecular markers were developed and used in combination with disease tests to fine-map the genes to a small genomic region (approximately 70 kb. Using a Tobacco Rattle Virus-Virus Induced Gene Silencing approach, the resistance gene was identified. It is shown that Ty-1 and Ty-3 are allelic and that they code for a RNA-dependent RNA polymerase (RDR belonging to the RDRγ type, which has an atypical DFDGD motif in the catalytic domain. In contrast to the RDRα type, characterized by a catalytic DLDGD motif, no clear function has yet been described for the RDRγ type, and thus the Ty-1/Ty-3 gene unveils a completely new class of resistance gene. Although speculative, the resistance mechanism of Ty-1/Ty-3 and its specificity towards TYLCV are discussed in light of the function of the related RDRα class in the amplification of the RNAi response in plants and transcriptional silencing of geminiviruses in plants.

  3. Resistance to Varroa destructor (Mesostigmata: Varroidae) when mite-resistant queen honey bees (Hymenoptera: Apidae) were free-mated with unselected drones.

    Science.gov (United States)

    Harbo, J R; Harris, J W

    2001-12-01

    This study demonstrated (1) that honey bees, Apis mellifera L, can express a high level of resistance to Varroa destructor Anderson & Trueman when bees were selected for only one resistant trait (suppression of mite reproduction); and (2) that a significant level of mite-resistance was retained when these queens were free-mated with unselected drones. The test compared the growth of mite populations in colonies of bees that each received one of the following queens: (1) resistant--queens selected for suppression of mite reproduction and artificially inseminated in Baton Rouge with drones from similarly selected stocks; (2) resistant x control--resistant queens, as above, produced and free-mated to unselected drones by one of four commercial queen producers; and (3) control--commercial queens chosen by the same four queen producers and free-mated as above. All colonies started the test with approximately 0.9 kg of bees that were naturally infested with approximately 650 mites. Colonies with resistant x control queens ended the 115-d test period with significantly fewer mites than did colonies with control queens. This suggests that beekeepers can derive immediate benefit from mite-resistant queens that have been free-mated to unselected drones. Moreover, the production and distribution of these free-mated queens from many commercial sources may be an effective way to insert beneficial genes into our commercial population of honey bees without losing the genetic diversity and the useful beekeeping characteristics of this population.

  4. Comparative performance of two mite-resistant stocks of honey bees (Hymenoptera: Apidae) in Alabama beekeeping operations.

    Science.gov (United States)

    Ward, Kenneth; Danka, Robert; Ward, Rufina

    2008-06-01

    The utility of USDA-developed Russian and varroa sensitive hygiene (VSH) honey bees, Apis mellifera L. (Hymenoptera: Apidae), was compared with that of locally produced, commercial Italian bees during 2004-2006 in beekeeping operations in Alabama, USA. Infestations of varroa mites, Varroa destructor Anderson & Truman (Acari: Varroidae), were measured twice each year, and colonies that reached established economic treatment thresholds (one mite per 100 adult bees in late winter; 5-10 mites per 100 adult bees in late summer) were treated with acaricides. Infestations of tracheal mites, Acarapis woodi (Rennie) (Acari: Tarsonemidae), were measured autumn and compared with a treatment threshold of 20% mite prevalence. Honey production was measured in 2005 and 2006 for colonies that retained original test queens. Throughout the three seasons of measurement, resistant stocks required less treatment against parasitic mites than the Italian stock. The total percentages of colonies needing treatment against varroa mites were 12% of VSH, 24% of Russian, and 40% of Italian. The total percentages requiring treatment against tracheal mites were 1% of Russian, 8% of VSH and 12% of Italian. The average honey yield of Russian and VSH colonies was comparable with that of Italian colonies each year. Beekeepers did not report any significant behavioral problems with the resistant stocks. These stocks thus have good potential for use in nonmigratory beekeeping operations in the southeastern United States.

  5. Resistance to the parasitic mite Varroa destructor in honey bees from far-eastern Russia

    OpenAIRE

    Rinderer, Thomas; Guzman, Lilia; Delatte, G.; Stelzer, J.; Lancaster, V.; Kuznetsov, V.; Beaman, L; Watts, R.; Harris, J.

    2001-01-01

    International audience; Varroa destructor is a parasitic mite of the Asian honey bee, Apis cerana. Owing to host range expansion, it now plagues Apis mellifera, the world's principal crop pollinator and honey producer. Evidence from A. mellifera in far-eastern Russia, Primorsky (P) originating from honey bees imported in the mid 1800's, suggested that many colonies were resistant to V. destructor. A controlled field study of the development of populations of V. destructor shows that P colonie...

  6. Response of resistant breeding lines of tomato germplasm and their progenies with Seedathip3 to Tomato Yellow Leaf Curl Virus, Thailand isolate (TYLCTHV-[2

    Directory of Open Access Journals (Sweden)

    Ornubol Chomdej

    2007-11-01

    Full Text Available Tomato germplasm accessions; FLA456-4, FLA591-15, H24, CLN2443A, CLN2443B, CLN2443C, TLB111, TLB182-1, TLB111-F6-4-1, TLB130-F6-3-1 and TLB134-F6-8-1 from the Asian Vegetable Research Development Center (AVRDC, Taiwan, were screened for resistance to the Tomato Yellow Leaf Curl Virus, Thailand isolate (TYLCTHV-[2]. The accessions expressing the resistant genotype were then crossed to the TYLCV-susceptible female parent, Seedathip3 (SD3, to produce F1 hybrids. Tomato parents and their F1 progenies were inoculated with TYLCTHV-[2] at 3 weeks of seedling age using viruliferous whitefly (Bemisia tabaci as the inoculation vector. Disease response of the seedling was rated according to the incidence and severity of the development of yellowing and curling symptoms. The presence of TYLCTHV-[2] in the inoculated plants was confirmed by Enzyme-Linked Immunosorbent Assay (ELISA. AVRDC tomato parental lines: H24, FLA591-15 and FLA456-4 expressed mild or no symptoms after one month inoculation. Progeny of crosses between the AVRDC donor parental lines and susceptible Thai cultivars showed intermediate tolerance to TYLCTHV-[2] infection. This indicated that resistance was incompletely dominant.

  7. A link between host plant adaptation and pesticide resistance in the polyphagous spider mite Tetranychus urticae.

    Science.gov (United States)

    Dermauw, Wannes; Wybouw, Nicky; Rombauts, Stephane; Menten, Björn; Vontas, John; Grbic, Miodrag; Clark, Richard M; Feyereisen, René; Van Leeuwen, Thomas

    2013-01-08

    Plants produce a wide range of allelochemicals to defend against herbivore attack, and generalist herbivores have evolved mechanisms to avoid, sequester, or detoxify a broad spectrum of natural defense compounds. Successful arthropod pests have also developed resistance to diverse classes of pesticides and this adaptation is of critical importance to agriculture. To test whether mechanisms to overcome plant defenses predispose the development of pesticide resistance, we examined adaptation of the generalist two-spotted spider mite, Tetranychus urticae, to host plant transfer and pesticides. T. urticae is an extreme polyphagous pest with more than 1,100 documented hosts and has an extraordinary ability to develop pesticide resistance. When mites from a pesticide-susceptible strain propagated on bean were adapted to a challenging host (tomato), transcriptional responses increased over time with ~7.5% of genes differentially expressed after five generations. Whereas many genes with altered expression belonged to known detoxification families (like P450 monooxygenases), new gene families not previously associated with detoxification in other herbivores showed a striking response, including ring-splitting dioxygenase genes acquired by horizontal gene transfer. Strikingly, transcriptional profiles of tomato-adapted mites resembled those of multipesticide-resistant strains, and adaptation to tomato decreased the susceptibility to unrelated pesticide classes. Our findings suggest key roles for both an expanded environmental response gene repertoire and transcriptional regulation in the life history of generalist herbivores. They also support a model whereby selection for the ability to mount a broad response to the diverse defense chemistry of plants predisposes the evolution of pesticide resistance in generalists.

  8. An evaluation of the associations of parameters related to the fall of Varroa destructor (Acari: Varroidae) from commercial honey bee (Hymenoptera: Apidae) colonies as tools for selective breeding for mite resistance.

    Science.gov (United States)

    Rinderer, Thomas E; De Guzman, Lilia I; Frake, Amanda M; Tarver, Matthew R; Khongphinitbunjong, Kitiphong

    2014-04-01

    Varroa destructor (Anderson and Trueman) trapped on bottom boards were assessed as indirect measurements of colony mite population differences and potential indicators of mite resistance in commercial colonies of Russian and Italian honey bees (Apis mellifera L.) by using 35 candidate measurements. Measurements included numbers of damaged and nondamaged younger mites, nymphs, damaged and nondamaged older mites, fresh mites, and all mites, each as a proportion of total mites in the colonies and as a proportion of all trapped mites or all trapped fresh mites. Several measurements differed strongly between the stocks, suggesting that the detailed characteristics of trapped mites may reflect the operation of resistance mechanisms in the Russian honey bees. Regression analyses were used to determine the relationships of these candidate measurements with the number of mites in the colonies. The largest positive regressions differed for the two stocks (Italian honey bees: trapped mites and trapped younger mites; Russian honey bees: trapped younger mites and trapped fresh mites). Also, the regressions for Italian honey bees were substantially stronger. The largest negative regressions with colony mites for both stocks were for the proportion of older mites out of all trapped mites. Although these regressions were statistically significant and consistent with those previously reported, they were weaker than those previously reported. The numbers of mites in the colonies were low, especially in the Russian honey bee colonies, which may have negatively influenced the precision of the regressions.

  9. Parasitism of Sympetrum dragonflies by Arrenurus planus mites: maintenance of resistance particular to one species.

    Science.gov (United States)

    Forbes, M R; Muma, K E; Smith, B P

    1999-07-01

    Using field surveys and histological methods, we show that a dragonfly species (Sympetrum internum) has an effective resistance, not seen previously in other odonates, to a mite parasite (Arrenurus planus). This mite is a generalist parasite known to effectively engorge on several other odonate species. We argue that selection is likely weak, favouring counter adaptations of Arrenurus planus to Sympetrum internum, in part because other host species are available. We further argue that this pattern is possibly linked to the fact that the mode of resistance is relatively novel, and because Sympetrum internum is rare compared to another host species, Sympetrum obtrusum, at our study site. Although resistance of Sympetrum internum is quite effective against Arrenurus planus, Arrenurus planus larvae still attach to this species, but less often than they attach to Sympetrum obtrusum. Attachment to unsuitable hosts may reflect constraints operating on Arrenurus planus larvae during host discovery. Such factors influencing the evolution of resistance, when several potential host species exist, have not received much attention.

  10. Research Progresses on Pesticides Resistance of Predatory Mites%捕食螨的抗药性研究进展

    Institute of Scientific and Technical Information of China (English)

    赵海明; 唐良德; 胡美英; 耿鹏; 安国栋

    2012-01-01

    抗药性捕食螨的应用是IPM中生防和化防相结合的重要措施之一。本文综述了农药对捕食螨的影响、捕食螨抗药性现状、抗药性机制、抗药性监测方法、交互抗性及遗传改良等,并介绍了抗药性捕食螨的应用现状及前景,旨在充分保护和利用捕食螨,使生物防治与化学防治有机结合。%The use of pesticide-resistant predatory mites is an important aspect of pest management systems integrating chemical and biological control technologies.Influence of chemical pesticide on predatory mites,current situation of resistance,bioassay methods,mechanisms of resistance,cross resistance and genetic improvement of predatory mites were reviewed in this paper.In addition,application of pesticide-resistant predatory mites was reviewed and prospected.This review serves a baseline for the protection and utilization of predatory mites so as to integrate biological and chemical control technologies.

  11. The resistant mechanisms of plants to mites%植物的抗螨机理

    Institute of Scientific and Technical Information of China (English)

    雍小菊; 丁伟

    2011-01-01

    Phytophagous mites are widely distributed and cause damage to various host plants. Three aspects of plant resistance mechanisms are discussed;!. Plant morphology, Buch as leaf shape and leaf color, mainly affects the feeding and oviposition sites of mites and obtainable nutrients. 2. Tissue structures, Buch as leaf thickness, waxiness, leaf trichomes and stomata, may influence the ease of stylet penetrations and leaf domatia play an important role in the relationship between predatory mites and phytophagous mites. 3. Physical and chemical properties, such as leaf weight, growth rate and development stages, reflect recovery of plants from damage. The availability of water, carbon and nitrogen used for the production of soluble sugars, starch and amino acids, directly affects the feeding, growth and reproduction of mites. More critical and more influential are plant secondary metabolites, such as phenolic compounds, tannins, coumarina, flavonoids and alkaloids, amongst others. In addition, the effects of Bt-modified plants on phytophagous mites and natural enemies are discussed; the addition of the transgene does not have an obvious impact on phytophagous mites in short term, but mites on Bt-modified plants display a gradual increase in adverse demographic trends.%植食性螨类分布广泛,危害多种寄主植物.本文从3个方面介绍了植物的抗螨机理:植物形态如叶型、叶色主要影响螨类的取食产卵位点和营养物质的获取;植物组织结构如叶厚、蜡质、茸毛、气孔等决定螨能否顺利利用口针取食到植物的汁液,而虫菌穴则作用于捕食螨和植食性螨的相互关系,从而达到保护植物的目的;植物理化性质如叶鲜重、生长速度、生育期反映了植物受害后的恢复能力,植物营养成分如水分、氰、可溶性糖、淀粉、叶绿素、氨基酸等的含量会直接影响螨的取食、生长发育和繁殖等,而植物的次生代谢物质,如酚类化合物、单

  12. Whitefly population dynamics and evaluation of whitefly-transmitted tomato yellow leaf curl virus (TYLCV)-resistant tomato genotypes as whitefly and TYLCV reservoirs.

    Science.gov (United States)

    Srinivasan, Rajagopalbabu; Riley, David; Diffie, Stan; Sparks, Alton; Adkins, Scott

    2012-08-01

    Sweetpotato whitefly, Bemisia tabaci (Gennadius), and whitefly-transmitted tomato yellow leaf curl virus (TYLCV) are major threats to tomato production in the southeastern United States. TYLCV was introduced to Florida from the Caribbean islands and has spread to other southern states of the United States. In Georgia, in recent years, the incidence of TYLCV has been steadily increasing. Studies were conducted to monitor population dynamics of whiteflies in the vegetable production belt of Georgia, to evaluate TYLCV-resistant genotypes against whiteflies and TYLCV, and to assess the potential role of resistant genotypes in TYLCV epidemiology. Monitoring studies indicated that the peak incidence of whiteflies varied seasonally from year to year. In general, whitefly populations were not uniformly distributed. Tomato genotypes exhibited minor differences in their ability to support whitefly populations. TYLCV symptoms were visually undetectable in all but one resistant genotype. The infection rates (visually) in susceptible genotypes ranged from 40 to 87%. Greenhouse inoculations with viruliferous whiteflies followed by polymerase chain reaction (PCR) indicated that up to 100% of plants of resistant genotypes were infected, although predominantly symptomless. TYLCV acquisition by whiteflies from TYLCV-infected genotypes was tested by PCR; TYLCV acquisition rates from resistant genotypes were less than from susceptible genotypes. Nevertheless, this difference did not influence TYLCV transmission rates from resistant to susceptible genotypes. Results emphasize that resistant genotypes can serve as TYLCV and whitefly reservoirs and potentially influence TYLCV epidemics.

  13. Detection of the high risk pyrethroid resistant Varroa destructor mites in apiaries of the Warmia-Mazury province in Poland.

    Science.gov (United States)

    Lipiński, Zbigniew; Szubstarski, Jarosław; Szubstarska, Dagna

    2007-01-01

    The aim of our current study was to investigate the possible occurence of pyrethroid (taufluvalinate) resistant Varroa mites infestations in 24 randomly chosen apiaries of Warmia-Mazury province of northeast Poland. The methodology used for the analysis of resistant Varroa strains strictly followed the protocol described by Milani. We identified 3 apiaries that were infested with high risk pyrethroid resistance mites and a further 9 apiaries that were free from this resitance. The brood samples collected from the remaining apiaries did not contain sufficient numbers of parasites to enable us to properly perform the assay. Our finding that 25% of the tested brood samples showed a high risk of fully pyrethroid resistant Varroa mite contamination indicates that resistant Varroa may become wide spread in apiaries in Poland. Interestingly these high risk resistant mites were found in honeybee colonies with low levels of Varroa infestation, with an average rate of 2.16%. We also discuss the role of amitraz (amidine) in the phenomenon of Varroa resistance to pyrethroids.

  14. Susceptibility of Varroa destructor (Acari: Varroidae) to synthetic acaricides in Uruguay: Varroa mites' potential to develop acaricide resistance.

    Science.gov (United States)

    Maggi, Matías Daniel; Ruffinengo, Sergio Roberto; Mendoza, Yamandú; Ojeda, Pilar; Ramallo, Gustavo; Floris, Iganazio; Eguaras, Martín Javier

    2011-04-01

    The purpose of this study was to estimate the acaricide susceptibility of Varroa destructor populations from Uruguay, which had never been exposed to synthetic acaricides. It was also to determine whether acaricide resistance to coumaphos occurred in apiaries in which acaricide rotation had been applied. Bioassays with acaricides against mite populations that had never been exposed to synthetic acaricides were performed, also against mite populations in which control failures with coumaphos had been reported. Additionally, coumaphos' effectiveness in honeybee colonies was experimentally tested. The lethal concentration that kills 50% of the exposed animals (LC(50)) for susceptible mite populations amounted to 0.15 μg/Petri dish for coumaphos and to less than 0.3 μg/Petri dish for the other acaricides. Coumaphos LC(50) was above 40 μg/Petri dish for resistant mites. The effectiveness of coumaphos in honeybee colonies parasitized by V. destructor ranged from 17.6% to 93.9%. LC(50) for mite populations susceptible to the most commonly applied miticides was determined, and the first case of coumaphos resistance recorded in Uruguay was established.

  15. Resistance rather than tolerance explains survival of savannah honeybees (Apis mellifera scutellata) to infestation by the parasitic mite Varroa destructor.

    Science.gov (United States)

    Strauss, Ursula; Dietemann, Vincent; Human, Hannelie; Crewe, Robin M; Pirk, Christian W W

    2016-03-01

    Varroa destructor is considered the most damaging parasite affecting honeybees (Apis mellifera L.). However, some honeybee populations such as the savannah honeybee (Apis mellifera scutellata) can survive mite infestation without treatment. It is unclear if survival is due to resistance mechanisms decreasing parasite reproduction or to tolerance mechanisms decreasing the detrimental effects of mites on the host. This study investigates both aspects by quantifying the reproductive output of V. destructor and its physiological costs at the individual host level. Costs measured were not consistently lower when compared with susceptible honeybee populations, indicating a lack of tolerance. In contrast, reproduction of V. destructor mites was distinctly lower than in susceptible populations. There was higher proportion of infertile individuals and the reproductive success of fertile mites was lower than measured to date, even in surviving populations. Our results suggest that survival of savannah honeybees is based on resistance rather than tolerance to this parasite. We identified traits that may be useful for breeding programmes aimed at increasing the survival of susceptible populations. African honeybees may have benefited from a lack of human interference, allowing natural selection to shape a population of honeybees that is more resistant to Varroa mite infestation.

  16. Comparative transcriptome profiling of a resistant vs. susceptible tomato (Solanum lycopersicum cultivar in response to infection by tomato yellow leaf curl virus.

    Directory of Open Access Journals (Sweden)

    Tianzi Chen

    Full Text Available Tomato yellow leaf curl virus (TYLCV threatens tomato production worldwide by causing leaf yellowing, leaf curling, plant stunting and flower abscission. The current understanding of the host plant defense response to this virus is very limited. Using whole transcriptome sequencing, we analyzed the differential gene expression in response to TYLCV infection in the TYLCV-resistant tomato breeding line CLN2777A (R and TYLCV-susceptible tomato breeding line TMXA48-4-0 (S. The mixed inoculated samples from 3, 5 and 7 day post inoculation (dpi were compared to non-inoculated samples at 0 dpi. Of the total of 34831 mapped transcripts, 209 and 809 genes were differentially expressed in the R and S tomato line, respectively. The proportion of up-regulated differentially expressed genes (DEGs in the R tomato line (58.37% was higher than that in the S line (9.17%. Gene ontology (GO analyses revealed that similar GO terms existed in both DEGs of R and S lines; however, some sets of defense related genes and their expression levels were not similar between the two tomato lines. Genes encoding for WRKY transcriptional factors, R genes, protein kinases and receptor (-like kinases which were identified as down-regulated DEGs in the S line were up-regulated or not differentially expressed in the R line. The up-regulated DEGs in the R tomato line revealed the defense response of tomato to TYLCV infection was characterized by the induction and regulation of a series of genes involved in cell wall reorganization, transcriptional regulation, defense response, ubiquitination, metabolite synthesis and so on. The present study provides insights into various reactions underlining the successful establishment of resistance to TYLCV in the R tomato line, and helps in the identification of important defense-related genes in tomato for TYLCV disease management.

  17. Beyond Predation: The Zoophytophagous Predator Macrolophus pygmaeus Induces Tomato Resistance against Spider Mites.

    Science.gov (United States)

    Pappas, Maria L; Steppuhn, Anke; Geuss, Daniel; Topalidou, Nikoleta; Zografou, Aliki; Sabelis, Maurice W; Broufas, George D

    2015-01-01

    Many predatory insects that prey on herbivores also feed on the plant, but it is unknown whether plants affect the performance of herbivores by responding to this phytophagy with defence induction. We investigate whether the prior presence of the omnivorous predator Macrolophus pygmaeus (Rambur) on tomato plants affects plant resistance against two different herbivore species. Besides plant-mediated effects of M. pygmaeus on herbivore performance, we examined whether a plant defence trait that is known to be inducible by herbivory, proteinase inhibitors (PI), may also be activated in response to the interactions of this predator with the tomato plant. We show that exposing tomato plants to the omnivorous predator M. pygmaeus reduced performance of a subsequently infesting herbivore, the two-spotted spider mite Tetranychus urticae Koch, but not of the greenhouse whitefly Trialeurodes vaporariorum (Westwood). The spider-mite infested tomato plants experience a lower herbivore load, i.e., number of eggs deposited and individuals present, when previously exposed to the zoophytophagous predator. This effect is not restricted to the exposed leaf and persists on exposed plants for at least two weeks after the removal of the predators. The decreased performance of spider mites as a result of prior exposure of the plant to M. pygmaeus is accompanied by a locally and systemically increased accumulation of transcripts and activity of proteinase inhibitors that are known to be involved in plant defence. Our results demonstrate that zoophytophagous predators can induce plant defence responses and reduce herbivore performance. Hence, the suppression of populations of certain herbivores via consumption may be strengthened by the induction of plant defences by zoophytophagous predators.

  18. Beyond Predation: The Zoophytophagous Predator Macrolophus pygmaeus Induces Tomato Resistance against Spider Mites.

    Directory of Open Access Journals (Sweden)

    Maria L Pappas

    Full Text Available Many predatory insects that prey on herbivores also feed on the plant, but it is unknown whether plants affect the performance of herbivores by responding to this phytophagy with defence induction. We investigate whether the prior presence of the omnivorous predator Macrolophus pygmaeus (Rambur on tomato plants affects plant resistance against two different herbivore species. Besides plant-mediated effects of M. pygmaeus on herbivore performance, we examined whether a plant defence trait that is known to be inducible by herbivory, proteinase inhibitors (PI, may also be activated in response to the interactions of this predator with the tomato plant. We show that exposing tomato plants to the omnivorous predator M. pygmaeus reduced performance of a subsequently infesting herbivore, the two-spotted spider mite Tetranychus urticae Koch, but not of the greenhouse whitefly Trialeurodes vaporariorum (Westwood. The spider-mite infested tomato plants experience a lower herbivore load, i.e., number of eggs deposited and individuals present, when previously exposed to the zoophytophagous predator. This effect is not restricted to the exposed leaf and persists on exposed plants for at least two weeks after the removal of the predators. The decreased performance of spider mites as a result of prior exposure of the plant to M. pygmaeus is accompanied by a locally and systemically increased accumulation of transcripts and activity of proteinase inhibitors that are known to be involved in plant defence. Our results demonstrate that zoophytophagous predators can induce plant defence responses and reduce herbivore performance. Hence, the suppression of populations of certain herbivores via consumption may be strengthened by the induction of plant defences by zoophytophagous predators.

  19. Analysis of Transcriptome Differences between Resistant and Susceptible Strains of the Citrus Red Mite Panonychus citri (Acari: Tetranychidae)

    OpenAIRE

    Bin Liu; Gaofei Jiang; Yunfei Zhang; Junli Li; Xiaojiao Li; Jiansu Yue; Fei Chen; Haoqiang Liu; Hongjun Li; Shiping Zhu; Jinjun Wang; Chun Ran

    2011-01-01

    BACKGROUND: The citrus red mite is a worldwide citrus pest and a common sensitizing allergen of asthma and rhinitis. It has developed strong resistance to many registered acaricides, However, the molecular mechanisms of resistance remain unknown. we therefore used next generation sequencing technology to investigate the global transcriptomes between resistant strains and susceptible strains. RESULTS: We obtained 34,159, 30,466 and 32,217 unigenes by assembling the SS reads, RS reads and SS&RS...

  20. Tomato yellow leaf curl virus resistance by Ty-1 involves increased cytosine methylation of viral genomes and is compromised by cucumber mosaic virus infection.

    Science.gov (United States)

    Butterbach, Patrick; Verlaan, Maarten G; Dullemans, Annette; Lohuis, Dick; Visser, Richard G F; Bai, Yuling; Kormelink, Richard

    2014-09-02

    Tomato yellow leaf curl virus (TYLCV) and related begomoviruses are a major threat to tomato production worldwide and, to protect against these viruses, resistance genes from different wild tomato species are introgressed. Recently, the Ty-1 resistance gene was identified, shown to code for an RNA-dependent RNA polymerase and to be allelic with Ty-3. Here we show that upon TYLCV challenging of resistant lines carrying Ty-1 or Ty-3, low virus titers were detected concomitant with the production of relatively high levels of siRNAs whereas, in contrast, susceptible tomato Moneymaker (MM) revealed higher virus titers but lower amounts of siRNAs. Comparative analysis of the spatial genomic siRNA distribution showed a consistent and subtle enrichment for siRNAs derived from the V1 and C3 genes in Ty-1 and Ty-3. In plants containing Ty-2 resistance the virus was hardly detectable, but the siRNA profile resembled the one observed in TYLCV-challenged susceptible tomato (MM). Furthermore, a relative hypermethylation of the TYLCV V1 promoter region was observed in genomic DNA collected from Ty-1 compared with that from (MM). The resistance conferred by Ty-1 was also effective against the bipartite tomato severe rugose begomovirus, where a similar genome hypermethylation of the V1 promoter region was discerned. However, a mixed infection of TYLCV with cucumber mosaic virus compromised the resistance. The results indicate that Ty-1 confers resistance to geminiviruses by increasing cytosine methylation of viral genomes, suggestive of enhanced transcriptional gene silencing. The mechanism of resistance and its durability toward geminiviruses under natural field conditions is discussed.

  1. Mechanisms of insecticide resistance in field populations of varroa mite (Acari: Mesostigmata: Varroidae)in Florida

    Science.gov (United States)

    The ectoparasitic mite Varroa destuctor is a serious threat to beekeeping and crops that rely on honey bee for pollination. The Varroa mite not only causes significant damage to honey bees by feeding on their haemolymph, but also serves as a vector of disease. In addition, the Varroa mite has develo...

  2. Cross-resistance risk of the novel complex II inhibitors cyenopyrafen and cyflumetofen in resistant strains of the two-spotted spider mite Tetranychus urticae

    NARCIS (Netherlands)

    Khalighi, M.; Tirry, L.; Van Leeuwen, T.

    2014-01-01

    BACKGROUND: Cyflumetofen and cyenopyrafen are novel acaricides acting as complex II inhibitors. This new mode of action is extremely useful for devising efficient resistance management strategies for mite control. The authors determined the cross-resistance risk of both compounds, using a collection

  3. Eugenol confers resistance to Tomato yellow leaf curl virus (TYLCV) by regulating the expression of SlPer1 in tomato plants.

    Science.gov (United States)

    Sun, Wei-Jie; Lv, Wen-Jing; Li, Li-Na; Yin, Gan; Hang, Xiaofang; Xue, Yanfeng; Chen, Jian; Shi, Zhiqi

    2016-05-25

    Tomato yellow leaf curl virus (TYLCV) is one of the most devastating plant diseases, and poses a significant agricultural concern because of the lack of an efficient control method. Eugenol is a plant-derived natural compound that has been widely used as a food additive and in medicine. In the present study, we demonstrated the potential of eugenol to enhance the resistance of tomato plants to TYLCV. The anti-TYLCV efficiency of eugenol was significantly higher than that of moroxydine hydrochloride (MH), a widely used commercial antiviral agent. Eugenol application stimulated the production of endogenous nitric oxide (NO) and salicylic acid (SA) in tomato plants. The full-length cDNA of SlPer1, which has been suggested to be a host R gene specific to TYLCV, was isolated from tomato plants. A sequence analysis suggested that SlPer1 might be a nucleobase-ascorbate transporter (NAT) belonging to the permease family. The transcript levels of SlPer1 increased markedly in response to treatment with eugenol or TYLCV inoculation. The results of this study also showed that SlPer1 expression was strongly induced by SA, MeJA (jasmonic acid methyl ester), and NO. Thus, we propose that the increased transcription of SlPer1 contributed to the high anti-TYLCV efficiency of eugenol, which might involve in the generation of endogenous SA and NO. Such findings provide the basis for the development of eugenol as an environmental-friendly agricultural antiviral agent.

  4. Analysis of transcriptome differences between resistant and susceptible strains of the citrus red mite Panonychus citri (Acari: Tetranychidae.

    Directory of Open Access Journals (Sweden)

    Bin Liu

    Full Text Available BACKGROUND: The citrus red mite is a worldwide citrus pest and a common sensitizing allergen of asthma and rhinitis. It has developed strong resistance to many registered acaricides, However, the molecular mechanisms of resistance remain unknown. we therefore used next generation sequencing technology to investigate the global transcriptomes between resistant strains and susceptible strains. RESULTS: We obtained 34,159, 30,466 and 32,217 unigenes by assembling the SS reads, RS reads and SS&RS reads respectively. There are total 17,581 annotated unigenes from SS&RS reads by BLAST searching databases of nr, the Clusters of Orthologous Groups (COGs and Kyoto Encyclopedia of Genes and Genomes (KEGG with an E-value ≤ 1e-5, in which 7,075 unigenes were annotated in the COG database, 12, 712 unigenes were found in the KEGG database and 3,812 unigenes were assigned to Gene ontology (GO. Moreover, 2,701 unigenes were judged to be the differentially expressed genes (DEGs based on the uniquely mapped reads. There are 219 pathways in all annotated unigenes and 198 pathways in DEGs that mapped to the KEGG database. We identified 211 metabolism genes and target genes related to general insecticide resistance such as P450 and Cytochrome b, and further compared their differences between RS and SS. Meanwhile, we identified 105 and 194 genes related to growth and reproduction, respectively, based on the mode of action of Hexythiazox. After further analyses, we found variation in sequences but not in gene expression related to mite growth and reproduction between different strains. CONCLUSION: To our knowledge, this is the first comparative transcriptome study to discover candidate genes involved in phytophagous mite resistance. This study identified differential unigenes related to general pesticide resistance and organism growth and reproduction in P. citri. The assembled, annotated transcriptomes provide a valuable genomic resource for further understanding

  5. The Molecular Evolution of Xenobiotic Metabolism and Resistance in Chelicerate Mites.

    Science.gov (United States)

    Van Leeuwen, Thomas; Dermauw, Wannes

    2016-01-01

    Chelicerate mites diverged from other arthropod lineages more than 400 million years ago and subsequently developed specific and remarkable xenobiotic adaptations. The study of the two-spotted spider mite, Tetranychus urticae, for which a high-quality Sanger-sequenced genome was first available, revealed expansions and radiations in all major detoxification gene families, including P450 monooxygenases, carboxyl/cholinesterases, glutathione-S-transferases, and ATP-binding cassette transporters. Novel gene families that are not well studied in other arthropods, such as major facilitator family transporters and lipocalins, also reflect the evolution of xenobiotic adaptation. The acquisition of genes by horizontal gene transfer provided new routes to handle toxins, for example, the β-cyanoalanine synthase enzyme that metabolizes cyanide. The availability of genomic resources for other mite species has allowed researchers to study the lineage specificity of these gene family expansions and the distinct evolution of genes involved in xenobiotic metabolism in mites. Genome-based tools have been crucial in supporting the idiosyncrasies of mite detoxification and will further support the expanding field of mite-plant interactions.

  6. An analysis of potential resistance of the phytophagous mite, Tetranychus urticae Koch (Acari: Tetranychidae to four botanical pesticides

    Directory of Open Access Journals (Sweden)

    Attia, S.

    2015-01-01

    Full Text Available Description of the subject. Synthetic acaricides have been widely used to manage Tetranychus urticae. Due to the excessive use of biocide and the associated problems of pesticide resistance and environmental pollution, there is an increasing demand for sustainable, environmentally-friendly control methods. Among the current alternative strategies aimed at decreasing the pest populations, the pesticides based on plant extracts are currently one of the most promising methods. Essential oils with acaricidal properties have been categorized as green pesticides because they are biodegradable and predominantly non-toxic to vertebrates. Objectives. With an aim to reduce the use of synthetic pesticides, they represent a promising approach for eco-chemical control of mites. Method. The aim of the present work was to analyze the risk of resistance emergence of T. urticae to repeated treatments with four plant extracts: Deverra scoparia Coss. & Durieu (Araliales: Apiaceae, Hertia cheirifolia (L. Kuntze (Asterales: Ateraceae, Santolina africana Jord. & Fourr. (Asterales: Asteraceae essential oils and garlic distillate Allium sativum L. (Asparagales: Alliaceae after 20 generations. Results. Repeated treatments with S. africana essential oil during 20 generations did not provoke an emergence of resistance while a low development of resistance was observed with H. cheirifolia, A. sativum and D. scoparia extracts. Conclusions. The efficacy of these extracts against the two spotted spider mite and their low development of resistance make them a promising use for pest management.

  7. Amplicon based RNA interference targeting V2 gene of cotton leaf curl Kokhran virus-Burewala strain can provide resistance in transgenic cotton plants

    Science.gov (United States)

    An RNAi based gene construct designated “C2” was used to target the V2 region of the cotton leaf curl virus (CLCuV) genome which is responsible for virus movement. The construct was transformed into two elite cotton varieties MNH-786 and VH-289. A shoot apex method of plant transformation using Agr...

  8. Inhibitory properties of cysteine protease pro-peptides from barley confer resistance to spider mite feeding.

    Directory of Open Access Journals (Sweden)

    M Estrella Santamaria

    Full Text Available C1A plant cysteine proteases are synthesized as pre-pro-enzymes that need to be processed to become active by the pro-peptide claves off from its cognate enzyme. These pro-sequences play multifunctional roles including the capacity to specifically inhibit their own as well as other C1A protease activities from diverse origin. In this study, it is analysed the potential role of C1A pro-regions from barley as regulators of cysteine proteases in target phytophagous arthropods (coleopteran and acari. The in vitro inhibitory action of these pro-sequences, purified as recombinant proteins, is demonstrated. Moreover, transgenic Arabidopsis plants expressing different fragments of HvPap-1 barley gene containing the pro-peptide sequence were generated and the acaricide function was confirmed by bioassays conducted with the two-spotted spider mite Tetranychus urticae. Feeding trials resulted in a significant reduction of leaf damage in the transgenic lines expressing the pro-peptide in comparison to non-transformed control and strongly correlated with an increase in mite mortality. Additionally, the analysis of the expression levels of a selection of potential mite targets (proteases and protease inhibitors revealed a mite strategy to counteract the inhibitory activity produced by the C1A barley pro-prodomain. These findings demonstrate that pro-peptides can control mite pests and could be applied as defence proteins in biotechnological systems.

  9. Inhibitory properties of cysteine protease pro-peptides from barley confer resistance to spider mite feeding.

    Science.gov (United States)

    Santamaria, M Estrella; Arnaiz, Ana; Diaz-Mendoza, Mercedes; Martinez, Manuel; Diaz, Isabel

    2015-01-01

    C1A plant cysteine proteases are synthesized as pre-pro-enzymes that need to be processed to become active by the pro-peptide claves off from its cognate enzyme. These pro-sequences play multifunctional roles including the capacity to specifically inhibit their own as well as other C1A protease activities from diverse origin. In this study, it is analysed the potential role of C1A pro-regions from barley as regulators of cysteine proteases in target phytophagous arthropods (coleopteran and acari). The in vitro inhibitory action of these pro-sequences, purified as recombinant proteins, is demonstrated. Moreover, transgenic Arabidopsis plants expressing different fragments of HvPap-1 barley gene containing the pro-peptide sequence were generated and the acaricide function was confirmed by bioassays conducted with the two-spotted spider mite Tetranychus urticae. Feeding trials resulted in a significant reduction of leaf damage in the transgenic lines expressing the pro-peptide in comparison to non-transformed control and strongly correlated with an increase in mite mortality. Additionally, the analysis of the expression levels of a selection of potential mite targets (proteases and protease inhibitors) revealed a mite strategy to counteract the inhibitory activity produced by the C1A barley pro-prodomain. These findings demonstrate that pro-peptides can control mite pests and could be applied as defence proteins in biotechnological systems.

  10. Resistance to tomato yellow leaf curl Thailand virus,TYLCTHV-[2] from Solanum habrochaites accession ‘L06112’ in F1 and BC1F1 generations

    Directory of Open Access Journals (Sweden)

    Julapark Chunwongse4

    2008-07-01

    Full Text Available Resistance to tomato yellow leaf curl disease caused by Tomato yellow leaf curl Thailand virus (TYLCTHV-[2] inwild tomato, Solanum habrochaites ‘L06112’ was investigated. The ‘L06112’ accession expressing the resistant phenotypewas crossed to the TYLCV-susceptible female parent, Seedathip3, to produce F1 hybrids. Parental polymorphism and hybrididentity were tested using 12 pairs of microsatellite markers for each chromosome. All markers were polymorphic betweenthe parents, but only markers SSR46, SSR115, SSR117 and SSR128 gave results suitable to assess hybrid relationships.Polymorphic bands were sharp, concise and distinguishable between hybrids and selfed plants. The stem cuttings of donorand recurrent parents, their F1 and BC1F1 were inoculated with TYLCTHV-[2] using viruliferous whiteflies. Diseaseresponse of the plants was evaluated by Enzyme-Linked Immunosorbent Assay (ELISA at 45 days post inoculation. Thedonor parental line showed complete resistance to TYLCTHV-[2] while the F1 and BC1F1 expressed various ELISA readingsfor TYLCTHV-[2] concentration. BC1F1; 04T105-7, 04T105-1, 04T105-10, 04T109-4 and 04T104-1 developed from thisstudy showed the high level of resistance to TYLCV, Thailand isolate.

  11. Genetic basis of resistances to chlorfenapyr and etoxazole in the two-spotted spider mite (Acari: Tetranychidae).

    Science.gov (United States)

    Uesugi, R; Goka, K; Osakabe, Mh

    2002-12-01

    We studied the genetic basis of resistance to two new acaricides, chlorfenapyr and etoxazole, which have different chemical structures and modes of action in the two-spotted spider mite, Tetranychus urticae Koch. The resistance ratios calculated from the LC50s of resistant and susceptible strains were 483 for chlorfenapyr and >100,000 for etoxazole. Mortality caused by the two acaricides in F1 progeny from reciprocal crosses between the resistant and susceptible strains indicated that the modes of inheritance of resistance to chlorfenapyr and etoxazole were completely dominant and completely recessive, respectively. Mortality in F2 progeny indicated that for both acaricides, the resistance was under monogenic control. Repeated backcross experiments indicated a linkage relationship among the two acaricide resistances and malate dehydrogenase, although phosphoglucoisomerase was not linked with them. The recombination ratio between the resistances was 14.8%. From this result, we suggest that heavy spraying of the two acaricides will lead to apparent cross-resistance as a consequence of crossing over; the two resistance genes are so close to each other that it would be difficult to segregate them once they came together on the same chromosome.

  12. Resistance to fresh and salt water in intertidal mites (Acari: Oribatida): implications for ecology and hydrochorous dispersal.

    Science.gov (United States)

    Pfingstl, Tobias

    2013-09-01

    The resistance to fresh water and seawater in three intertidal oribatid mite species from Bermuda, Alismobates inexpectatus, Fortuynia atlantica and Carinozetes bermudensis, was tested in laboratory experiments. Larvae are more sensitive to fresh and salt water, nymphs and adults showed equal tolerances. Fortuynia atlantica and A. inexpectatus were more resistant to salt water whereas C. bermudensis survived longer in fresh water. Differences in the resistance to fresh and salt water among the three species may be related to their different vertical occurrences in the eulittoral zone but also to the ability of single species to dwell in periodically brackish waters. In all three species half of the specimens survived at least 10 days in fresh water and more than 18 days in salt water. Maximal submersion time in fresh and salt water ranged from 40 to 143 days. Based on median lethal times it could be estimated that each species would be able to survive transport in seawater along the Gulf Stream over a distance of 3,000 km, from Central America to Bermuda. Thus hydrochorous dispersal should be assumed as the most likely mode of dispersal in intertidal fortuyniid and selenoribatid mites.

  13. Whitefly resistance traits derived from the wild tomato Solanum pimpinellifolium affect the preference and feeding behavior of Bemisia tabaci and reduce the spread of Tomato yellow leaf curl virus.

    Science.gov (United States)

    Rodríguez-López, M J; Garzo, E; Bonani, J P; Fereres, A; Fernández-Muñoz, R; Moriones, E

    2011-10-01

    Breeding of tomato genotypes that limit whitefly (Bemisia tabaci) access and feeding might reduce the spread of Tomato yellow leaf curl virus (TYLCV), a begomovirus (genus Begomovirus, family Geminiviridae) that is the causal agent of tomato yellow leaf curl disease. TYLCV is restricted to the phloem and is transmitted in a persistent manner by B. tabaci. The tomato breeding line ABL 14-8 was developed by introgressing type IV leaf glandular trichomes and secretion of acylsucroses from the wild tomato Solanum pimpinellifolium accession TO-937 into the genetic background of the whitefly- and virus-susceptible tomato cultivar Moneymaker. Results of preference bioassays with ABL 14-8 versus Moneymaker indicated that presence of type IV glandular trichomes and the production of acylsucrose deterred the landing and settling of B. tabaci on ABL 14-8. Moreover, electrical penetration graph studies indicated that B. tabaci adults spent more time in nonprobing activities and showed a reduced ability to start probing. Such behavior resulted in a reduced ability to reach the phloem. The superficial type of resistance observed in ABL 14-8 against B. tabaci probing significantly reduced primary and secondary spread of TYLCV.

  14. Making a friend from a foe: expressing a GroEL gene from the whitefly Bemisia tabaci in the phloem of tomato plants confers resistance to tomato yellow leaf curl virus.

    Science.gov (United States)

    Akad, F; Eybishtz, A; Edelbaum, D; Gorovits, R; Dar-Issa, O; Iraki, N; Czosnek, H

    2007-01-01

    Some (perhaps all) plant viruses transmitted in a circulative manner by their insect vectors avoid destruction in the haemolymph by interacting with GroEL homologues, ensuring transmission. We have previously shown that the phloem-limited begomovirus tomato yellow leaf curl virus (TYLCV) interacts in vivo and in vitro with GroEL produced by the whitefly vector Bemisia tabaci. In this study, we have exploited this phenomenon to generate transgenic tomato plants expressing the whitefly GroEL in their phloem. We postulated that following inoculation, TYLCV particles will be trapped by GroEL in the plant phloem, thereby inhibiting virus replication and movement, thereby rendering the plants resistant. A whitefly GroEL gene was cloned in an Agrobacterium vector under the control of an Arabidopsis phloem-specific promoter, which was used to transform two tomato genotypes. During three consecutive generations, plants expressing GroEL exhibited mild or no disease symptoms upon whitefly-mediated inoculation of TYLCV. In vitro assays indicated that the sap of resistant plants contained GroEL-TYLCV complexes. Infected resistant plants served as virus source for whitefly-mediated transmission as effectively as infected non-transgenic tomato. Non-transgenic susceptible tomato plants grafted on resistant GroEL-transgenic scions remained susceptible, although GroEL translocated into the grafted plant and GroEL-TYLCV complexes were detected in the grafted tissues.

  15. Chlorfenapyr resistance in two-spotted spider mite (Acari: Tetranychidae) from Australian cotton.

    Science.gov (United States)

    Herron, G A; Rophail, J; Wilson, L J

    2004-01-01

    The responses of Tetranychus urticae Koch from Australian cotton to chlorfenapyr has been monitored since the 1997--1998 growing season. Resistance was first detected in the 2001--2002 season and then increased quickly in both level and proportion of resistant strains detected. In response, the resistance management strategy for chlorfenapyr use in cotton was altered and now recommends a further restriction of use from two to one spray per season. There was no evidence of negative cross-resistance to the pyrethroid bifenthrin, but chlorfenapyr was associated with an undefined negative cross-resistance.

  16. Resistance mutation conserved between insects and mites unravels the benzoylurea insecticide mode of action on chitin biosynthesis.

    Science.gov (United States)

    Douris, Vassilis; Steinbach, Denise; Panteleri, Rafaela; Livadaras, Ioannis; Pickett, John Anthony; Van Leeuwen, Thomas; Nauen, Ralf; Vontas, John

    2016-12-20

    Despite the major role of chitin biosynthesis inhibitors such as benzoylureas (BPUs) in the control of pests in agricultural and public health for almost four decades, their molecular mode of action (MoA) has in most cases remained elusive. BPUs interfere with chitin biosynthesis and were thought to interact with sulfonylurea receptors that mediate chitin vesicle transport. Here, we uncover a mutation (I1042M) in the chitin synthase 1 (CHS1) gene of BPU-resistant Plutella xylostella at the same position as the I1017F mutation reported in spider mites that confers etoxazole resistance. Using a genome-editing CRISPR/Cas9 approach coupled with homology-directed repair (HDR) in Drosophila melanogaster, we introduced both substitutions (I1056M/F) in the corresponding fly CHS1 gene (kkv). Homozygous lines bearing either of these mutations were highly resistant to etoxazole and all tested BPUs, as well as buprofezin-an important hemipteran chitin biosynthesis inhibitor. This provides compelling evidence that BPUs, etoxazole, and buprofezin share in fact the same molecular MoA and directly interact with CHS. This finding has immediate effects on resistance management strategies of major agricultural pests but also on mosquito vectors of serious human diseases such as Dengue and Zika, as diflubenzuron, the standard BPU, is one of the few effective larvicides in use. The study elaborates on how genome editing can directly, rapidly, and convincingly elucidate the MoA of bioactive molecules, especially when target sites are complex and hard to reconstitute in vitro.

  17. Discovering Host Genes Involved in the Infection by the Tomato Yellow Leaf Curl Virus Complex and in the Establishment of Resistance to the Virus Using Tobacco Rattle Virus-based Post Transcriptional Gene Silencing

    Directory of Open Access Journals (Sweden)

    Rosa Lozano-Durán

    2013-03-01

    Full Text Available The development of high-throughput technologies allows for evaluating gene expression at the whole-genome level. Together with proteomic and metabolomic studies, these analyses have resulted in the identification of plant genes whose function or expression is altered as a consequence of pathogen attacks. Members of the Tomato yellow leaf curl virus (TYLCV complex are among the most important pathogens impairing production of agricultural crops worldwide. To understand how these geminiviruses subjugate plant defenses, and to devise counter-measures, it is essential to identify the host genes affected by infection and to determine their role in susceptible and resistant plants. We have used a reverse genetics approach based on Tobacco rattle virus-induced gene silencing (TRV-VIGS to uncover genes involved in viral infection of susceptible plants, and to identify genes underlying virus resistance. To identify host genes with a role in geminivirus infection, we have engineered a Nicotiana benthamiana line, coined 2IRGFP, which over-expresses GFP upon virus infection. With this system, we have achieved an accurate description of the dynamics of virus replication in space and time. Upon silencing selected N. benthamiana genes previously shown to be related to host response to geminivirus infection, we have identified eighteen genes involved in a wide array of cellular processes. Plant genes involved in geminivirus resistance were studied by comparing two tomato lines: one resistant (R, the other susceptible (S to the virus. Sixty-nine genes preferentially expressed in R tomatoes were identified by screening cDNA libraries from infected and uninfected R and S genotypes. Out of the 25 genes studied so far, the silencing of five led to the total collapse of resistance, suggesting their involvement in the resistance gene network. This review of our results indicates that TRV-VIGS is an exquisite reverse genetics tool that may provide new insights into the

  18. In vitro efficacy of ByeMite and Mite-Stop on developmental stages of the red chicken mite Dermanyssus gallinae.

    Science.gov (United States)

    Abdel-Ghaffar, Fathy; Semmler, Margit; Al-Rasheid, Khaled; Mehlhorn, Heinz

    2009-10-01

    The present in vitro study shows the efficacy of two antimite products (ByeMite = phoxim, Mite-Stop = neem seed extract) against all developing stages of the important red chicken mite Dermanyssus gallinae (obtained at two farms in France and Germany). While permanent contact with the active compound led to an efficacy of 100% in the case of Mite-Stop on mites in both farms, there was only a 96.2% killing effect of ByeMite on the mites of the French farm. Even short contacts of only 4 s killed 100% of mites in the case of Mite-Stop at the French farm and only 84.5% in the German farm. ByeMite, on the other hand, killed only 27.8% (Germany) and 30% (France) when mites got the chance to escape from the treated grounds to untreated ones. When using only the half doses of both products, Mite-Stop(R) still reached, after permanent contact, 100% activity on the German farm and 98.2% in France, while ByeMite killed 93.8% (Germany) and 90.6% (France). Short contact to half doses of course reduced the activity of both products (Mite-Stop = 59.3% in France, 22.1% in Germany; ByeMite = 28.8% in France, 18.8% in Germany). With respect to the fumigant activity of the products, the strains of D. gallinae reacted differently. While Mite-Stop(R) showed a clear fumigant activity in the case of the German mites, this product did not affect the French mites by air distribution, neither did ByeMite in both cases. Therefore, mites have to come in contact with both products. Against Mite-Stop, there was apparently no resistance and low doses have high efficacy after even short contacts, which regularly occur in a treated stable, where mites have the chance to leave treated places to untreated hidden spots.

  19. Expression of a barley cystatin gene in maize enhances resistance against phytophagous mites by altering their cysteine-proteases.

    Science.gov (United States)

    Carrillo, Laura; Martinez, Manuel; Ramessar, Koreen; Cambra, Inés; Castañera, Pedro; Ortego, Felix; Díaz, Isabel

    2011-01-01

    Phytocystatins are inhibitors of cysteine-proteases from plants putatively involved in plant defence based on their capability of inhibit heterologous enzymes. We have previously characterised the whole cystatin gene family members from barley (HvCPI-1 to HvCPI-13). The aim of this study was to assess the effects of barley cystatins on two phytophagous spider mites, Tetranychus urticae and Brevipalpus chilensis. The determination of proteolytic activity profile in both mite species showed the presence of the cysteine-proteases, putative targets of cystatins, among other enzymatic activities. All barley cystatins, except HvCPI-1 and HvCPI-7, inhibited in vitro mite cathepsin L- and/or cathepsin B-like activities, HvCPI-6 being the strongest inhibitor for both mite species. Transgenic maize plants expressing HvCPI-6 protein were generated and the functional integrity of the cystatin transgene was confirmed by in vitro inhibitory effect observed against T. urticae and B. chilensis protein extracts. Feeding experiments impaired on transgenic lines performed with T. urticae impaired mite development and reproductive performance. Besides, a significant reduction of cathepsin L-like and/or cathepsin B-like activities was observed when the spider mite fed on maize plants expressing HvCPI-6 cystatin. These findings reveal the potential of barley cystatins as acaricide proteins to protect plants against two important mite pests.

  20. Tomato yellow leaf curl Sardinia virus-resistant tomato plants expressing the multifunctional N-terminal domain of the replication-associated protein show transcriptional changes resembling stress-related responses.

    Science.gov (United States)

    Lucioli, Alessandra; Berardi, Alessandra; Gatti, Francesca; Tavazza, Raffaela; Pizzichini, Daniele; Tavazza, Mario

    2014-01-01

    The N-terminal domain (amino acids 1-130) of the replication-associated protein (Rep130 ) of Tomato yellow leaf curl Sardinia virus (TYLCSV) retains the ability of full-length Rep to localize to the nucleus and to down-regulate C1 transcription when ectopically expressed in plants, both functions being required to inhibit homologous viral replication. In this study, we analysed the effect of Rep130 expression on virus resistance and the plant transcriptome in the natural and agronomically important host species of TYLCSV, Solanum lycopersicum. Tomato plants accumulating high levels of Rep130 were generated and proved to be resistant to TYLCSV. Using an in vitro assay, we showed that plant-expressed Rep130 also retains the catalytic activity of Rep, thus supporting the notion that this protein domain is fully functional. Interestingly, Rep130 -expressing tomatoes were characterized by an altered transcriptional profile resembling stress-related responses. Notably, the serine-type protease inhibitor (Ser-PI) category was over-represented among the 20 up-regulated genes. The involvement of Rep130 in the alteration of host mRNA steady-state levels was confirmed using a distinct set of virus-resistant transgenic tomato plants expressing the same TYLCSV Rep130 , but from a different, synthetic, gene. Eight genes were found to be up-regulated in both types of transgenic tomato and two encoded Ser-PIs. Four of these eight genes were also up-regulated in TYLCSV-infected wild-type tomato plants. Implications with regard to the ability of this Rep domain to interfere with viral infections and to alter the host transcriptome are discussed.

  1. Genotypic variability and relationships between mite infestation levels, mite damage, grooming intensity, and removal of Varroa destructor mites in selected strains of worker honey bees (Apis mellifera L.).

    Science.gov (United States)

    Guzman-Novoa, Ernesto; Emsen, Berna; Unger, Peter; Espinosa-Montaño, Laura G; Petukhova, Tatiana

    2012-07-01

    The objective of this study was to demonstrate genotypic variability and analyze the relationships between the infestation levels of the parasitic mite Varroa destructor in honey bee (Apis mellifera) colonies, the rate of damage of fallen mites, and the intensity with which bees of different genotypes groom themselves to remove mites from their bodies. Sets of paired genotypes that are presumably susceptible and resistant to the varroa mite were compared at the colony level for number of mites falling on sticky papers and for proportion of damaged mites. They were also compared at the individual level for intensity of grooming and mite removal success. Bees from the "resistant" colonies had lower mite population rates (up to 15 fold) and higher percentages of damaged mites (up to 9 fold) than bees from the "susceptible" genotypes. At the individual level, bees from the "resistant" genotypes performed significantly more instances of intense grooming (up to 4 fold), and a significantly higher number of mites were dislodged from the bees' bodies by intense grooming than by light grooming (up to 7 fold) in all genotypes. The odds of mite removal were high and significant for all "resistant" genotypes when compared with the "susceptible" genotypes. The results of this study strongly suggest that grooming behavior and the intensity with which bees perform it, is an important component in the resistance of some honey bee genotypes to the growth of varroa mite populations. The implications of these results are discussed.

  2. Resistência de genótipos de tomateiro ao ácaro rajado Resistance of tomato genotypes to spider mite

    Directory of Open Access Journals (Sweden)

    Wilson Itamar Maruyama

    2002-09-01

    Full Text Available Avaliou-se a resistência de genótipos de tomateiro selvagens [Lycopersicon pennellii (LA 716, L. hirsutum var. glabratum (PI 126449, PI 134417, L. hirsutum (PI 127826, PI 127827, L. peruvianum (CGO 6707, L. peruvianum var. dentatum (WYR 2020, LA 111, L. peruvianum var. glandulosum (LA 1113-1, LA 1113-2] e comerciais [(L. esculentum Gem Pride, Santa Clara, e híbridos Bruna VFN, Carmem, Fortaleza, Débora Plus VFN] ao ácaro rajado (Tetranychus urticae. O número médio de ovos, fases imaturas (larvas, protoninfas e deutoninfas e adultos por folíolo foi contado; o índice de preferência para oviposição (IPO foi calculado. O delineamento experimental foi blocos ao acaso, com 6 repetições. Os genótipos LA 716, PI 126449, PI 134417, PI 127827, PI 127826 e Gem Pride apresentaram não-preferência para oviposição do ácaro rajado, sendo deterrentes quanto à classificação do IPO, enquanto os genótipos LA 111, WYR 2020, LA 1113-2 e LA1113-1 foram os mais preferidos para a oviposição e foram considerados como estimulantes pelo IPO.The resistance of different tomato genotypes to spider mite (Tetranychus urticae was evaluated. The wild genotypes evaluated were Lycopersicon pennellii (LA 716, L. hirsutum f. glabratum (PI 126449, PI 134417, L. hirsutum (PI 127826, PI 127827, L. peruvianum (CGO 6707, L. peruvianum f. dentatum (WYR 2020, LA 111, L. peruvianum f. glandulosum (LA 1113-1, LA 1113-2; and the commercial genotypes (L. esculentum were Gem Pride, Santa Clara, and the F1 hybrids Bruna VFN, Carmem, Fortaleza and Débora Plus VFN. The number of eggs was counted, young phases (larvae, protonimphs, deutonimphs and adults per leafleft. After the counting, the index of oviposition preference (IOP also was calculated. The experiment was realized in randomized block design, with six replications. The LA 716, PI 126449, PI 134417, PI 127827, PI 127826 and Gem Pride genotypes showed non-preference for spider mite oviposition, being deterrents

  3. Mite allergy and mite exposure in Iceland.

    Science.gov (United States)

    Hallas, Thorkil E; Gislason, Thorarinn; Gislason, David

    2011-01-01

    In this overview of investigations into mite allergy in Iceland and of the current understanding of the sources of exposure, 2 major categories of mite-induced allergies were encountered. The first was house dust mite allergy due to house dust mites from unknown sources, and the second was barn allergy caused by mites connected with the degradation of stored hay. Characteristics of these diseases have been obtained from surveys where skin prick tests were made with commercially available extracts of mites and from zoological investigations where mites had been found in different kinds of dusts relevant for the tested persons. The investigations uncovered a discrepancy between the capital Reykjavik and countryside farms. While the frequencies of sensitization to house dust mites and barn mites are rather similar in the capital area and in the rural area, the exposure to these mites is unexpectedly low in the capital area. Thus, sensitization appears to take place preferably in the rural area.

  4. 抗番茄黄化卷叶病毒番茄新品种'科大204'%A New Tomato Hybrid'Keda 204'with Resistance to Tomato yellow leaf curl virus

    Institute of Scientific and Technical Information of China (English)

    宋建军; 艾鹏飞; 李振侠; 仇燕; 李敏

    2011-01-01

    '科大204' 番茄是以优良自交系'TP025-2'为母本,'869-1'为父本杂交育成的抗番茄黄化卷叶病毒的新品种.生长势强,无限生长类型,7~8片真叶着生第一花序.果实扁圆形,单果质量200~250g,成熟果粉红色,中等硬度,口感好,品质优良.抗番茄黄化卷叶病毒,兼抗枯萎病、叶霉病和TMV.中早熟,平均产量121.8 t·hm-2,适宜北方保护地早春和秋延后栽培.%‘Keds 204’ is a new pink tomato hybrid resistant to Tomato yellow leaf curl virus (TYLCV), which is developed by crossing ‘TP025-2’ × ‘869-1’ . The hybrid grows strongly with indeterminate plant type and mid-early maturity. The matured fruits are oblate in shape, pink in color with moderate firmness and good quality. The single fruit weight ranges from 200 g to 250 g. Especially, it is resistance to TYLCV, as well as fusarium wilt, leaf mould and TMV. The average yield of ‘Keda 204’was 121.8 t. hm-2 as a result of multiple experiments. The hybrid is suitable for cultivation in early spring and late autumn under greenhouse conditions in northern China.

  5. Identification of developmentally-specific kinotypes and mechanisms of Varroa mite resistance through whole-organism, kinome analysis of honeybee

    Directory of Open Access Journals (Sweden)

    Albert James Robertson

    2014-05-01

    Full Text Available Recent investigations associate Varroa destructor (Mesostigmata: Varroidae parasitism and its associated pathogens and agricultural pesticides with negative effects on colony health, resulting in sporadic global declines in domestic honeybee (Apis mellifera populations. These events have motivated efforts to develop research tools that can offer insight into the causes of declining bee health as well as identify biomarkers to guide breeding programs. Here we report the development of a bee-specific peptide array for characterizing global cellular kinase activity in whole bee extracts. The arrays reveal distinct, developmentally-specific signaling profiles between bees with differential susceptibility to infestation by Varroa mites. Gene ontology analysis of the differentially phosphorylated peptides indicates that the differential susceptibility to Varroa mite infestation does not reflect compromised immunity; rather, there is evidence for mite-mediated immune suppression within the susceptible phenotype that may reduce the ability of these bees to counter secondary viral infections. This hypothesis is supported by the demonstration of more diverse viral infections in mite-infested, susceptible adult bees. The bee-specific peptide arrays are an effective tool for understanding the molecular basis of this complex phenotype as well as for the discovery and utilization of phosphorylation biomarkers for breeding programs.

  6. Biology and control of Eriophyid mites with a case study of Aceria sp. on New Mexico olive (Forestiera pubescens Nutt. var. pubescens)

    Science.gov (United States)

    Tessa R. Grasswitz

    2012-01-01

    The biology, recognition, and impact of eriophyid mites (with emphasis on species associated with trees and shrubs) are briefly reviewed. A case study of a leaf-curling eriophyid mite (Aceria sp.) attacking New Mexico olive (Forestiera pubescens Nutt. var. pubescens) is used to illustrate the complexities of developing control strategies for eriophyids in native plant...

  7. Dust Mite Allergy

    Science.gov (United States)

    Dust mite allergy Overview By Mayo Clinic Staff Dust mite allergy is an allergic reaction to tiny bugs that commonly live in house dust. Signs of dust mite allergy include those common to hay fever, such as ...

  8. A New Tomato Hybrid‘Hangza 3’Resistant to Tomato yellow leaf curl virus%抗番茄黄化曲叶病毒番茄新品种‘航杂3号’

    Institute of Scientific and Technical Information of China (English)

    郑积荣; 王慧俐; 王世恒

    2012-01-01

    ‘Hangza 3’is a new red tomato hybrid resistant to Tomato yellow leaf curl virus(TYLCV) and root knot nematode,which is developed by crossing‘HT1-1-3-2-5-3’ב00-03-19’.The hybrid grows strongly with indeterminate plant type and mid-early maturity. Its first inflorescence is 7–8 leaf,Its average single fruit weight is 136 g. The matured fruits are round in shape,red in color with good quality. Especially,it is resistant to TYLCV and root knot nematode and transportation,The average yield of ‘Hangza 3’was 81.0 t · hm-2 as a result of multiple experiments. The hybrid is suitable for cultivation in early spring and late autumn under greenhouse conditions.%‘航杂3号’番茄是以引自荷兰品种‘9956’分离后代的高代自交系‘9956-3-2-1-1-1’经航天搭载诱变后选出的优良自交系‘HT1-1-3-2-5-3’为母本,以引自西班牙品种‘T00’高代自交系‘00-03-19’为父本,杂交育成的新品种。生长势强,无限生长类型,7~8片真叶着生第一花序。果实圆形,单果质量136g,成熟果大红色,耐贮运,商品性好。抗番茄黄化曲叶病毒,兼抗根结线虫病。中早熟,平均产量81.0t·hm-2,适宜保护地早春和秋延后栽培。

  9. Genetic control of leaf curl in maize.

    Science.gov (United States)

    Entringer, G C; Guedes, F L; Oliveira, A A; Nascimento, J P; Souza, J C

    2014-03-17

    Among the many implications of climatic change on agriculture, drought is expected to continue to have a major impact on agribusinesses. Leaf curling is an anatomical characteristic that might be potentially used to enhance plant tolerance to water deficit. Hence, we aimed to study the genetic control of leaf curl in maize. From 2 contrasting inbred lines for the trait, generations F1, F2, and the backcrosses were obtained. All of these generations were evaluated in a randomized block design with 2 replicates. Leaf curl samples were collected from 3 leaves above the first ear at the tasseling stage, and quantified by dividing the width of the leaf blade with natural curling against its extended width. The mean and variance components were estimated by the weighted least square method. It was found that the trait studied has predominance of the additive effects, with genetic control being attributed to few genes that favor selection and exhibit minimal influence from the environment.

  10. Screening Landraces for Additional Sources of Field Resistance to Cassava Mosaic Disease and Green Mite for Integration into the Cassava Improvement Program

    Institute of Scientific and Technical Information of China (English)

    Adebola Raji; Oluseyi Ladeinde; Alfred Dixon

    2008-01-01

    Twelve cassava landraces were evaluated for sources of resistance genes to diseases and pests of major economic importance in Africa. The objective was to assess their levels of field resistance to mosaic disease (ACMD), bacterial blight (CBB), anthracnose (CAD), and green mite (CGM), compared to TMS30572, an elite cultivar widely adopted in Africa. Considerable genotypic variation was observed among cultivars for resistance to ACMD and CGM but not for CBB and CAD. The lowest mean Incidence of 12% and severity of 1.8 on a scale of 1-5 for ACMD was recorded for Atu, a landrace with farmer acceptable qualities. In comparison, the improved cultivar, TMS 30572, had a mean disease incidence of 72% and a severity score of 2.8. Another landrace, MS-20 had the lowest CGM damage score (2.1) while TMS 30572 emerged as one of the susceptible cultivars with a damage score of 3. Additional sources of resistance to ACMD and CGM that may possibly be better than the popular improved cultivar, TMS 30572, were identified in this study. These could serve as novel sources of additional genes to complement existing resources for elite cassava breeding in Africa.

  11. Screening landraces for additional sources of field resistance to cassava mosaic disease and green mite for integration into the cassava improvement program.

    Science.gov (United States)

    Raji, Adebola; Ladeinde, Oluseyi; Dixon, Alfred

    2008-03-01

    Twelve cassava landraces were evaluated for sources of resistance genes to diseases and pests of major economic importance in Africa. The objective was to assess their levels of field resistance to mosaic disease (ACMD), bacterial blight (CBB), anthracnose (CAD), and green mite (CGM), compared to TMS30572, an elite cultivar widely adopted in Africa. Considerable genotypic variation was observed among cultivars for resistance to ACMD and CGM but not for CBB and CAD. The lowest mean incidence of 12% and severity of 1.8 on a scale of 1-5 for ACMD was recorded for Atu, a landrace with farmer acceptable qualities. In comparison, the improved cultivar, TMS 30572, had a mean disease incidence of 72% and a severity score of 2.8. Another landrace, MS-20 had the lowest CGM damage score (2.1) while TMS 30572 emerged as one of the susceptible cultivars with a damage score of 3. Additional sources of resistance to ACMD and CGM that may possibly be better than the popular improved cultivar, TMS 30572, were identified in this study. These could serve as novel sources of additional genes to complement existing resources for elite cassava breeding in Africa.

  12. Curl-meter of Electrical Fields In The Ground.

    Science.gov (United States)

    Krylov, S. M.; Maibuk, Z.-Ju. Ja.; Nikiforova, N. N.

    A special instrument U curl-meter was designed and manufactured in the Institute of Physics of the Earth of RAS for measuring of variable electric fields during alternation of stressedly-deformed state in rock mass. The instrument consist the four-electrode unit and a circuit of analogue signal processing for separation of E U circulations or according to the StokesSs theorem, Curl E in absence of indirect sources. Four electrodes are laied out in rocks on angles of square and they are affixed by ring-type circuit to uninverting inputs of precision operational amplifiers. First input is connected to electrode N1, the second one is connected to N2 and so on. The independent inputs are grounded to a arbitrary point (the fifth electrode is SzeroT). The transmission factors of the circuit are set by resistors accurate to within 0.25 %. First and third, and also second and fourth outputs of the amplifiers are connected to the grad EX and grad EY calculation circuit (deduction circuits). So, if the vector components have different signs of both two EX values and two values EY, the gradient calculation circuit generates signal extremums. If in this case the signs inside pairs are identical , that means that the signal not- ring-type and it is absent on output (difference of the equal values with equal signs). The signals from outputs of the gradient calculations act into adding device for calculation of Curl E (circulation). Curl-meter differs by high security from clutters and from cues on any of inputs rather of "zero point" (ground) reacting only on a ring-type current, thus it is essential (on the order) the noise level and drift of operational amplifiers is moderated. Curl-meter works in a complex of measuring devices on Obninsk seismological polygon for study of behavior of superlow frequency of tectonic genesis electromagnetic emission. Through four inputs (electrode spacing 7x7 2, resistance between welding rods 0.8 - 1.1 kOm), manufactured from fine- dyspersated

  13. Resistance to the two-spotted spider mite (Tetranychus urticae) by acylsucroses of wild tomato (Solanum pimpinellifolium) trichomes studied in a recombinant inbred line population.

    Science.gov (United States)

    Alba, Juan Manuel; Montserrat, Marta; Fernández-Muñoz, Rafael

    2009-01-01

    Trichome-based host plant resistance is a complex mechanism that could be used in tomato breeding to control arthropod pests. The aims of this work were to evaluate the plant traits (density of trichomes and acylsucrose production) and the functional relationships of these traits with mortality, repellence, and oviposition of Tetranychus urticae Koch (Acari: Tetranychidae). We used a population of recombinant inbred lines (RILs) derived from the cross between the wild tomato, Solanum pimpinellifolium L. 'TO-937', and the cultivated tomato, Solanum lycopersicum L. Multiple regression analyses showed that high acylsucrose content and high type-IV trichome density increased mortality and repellence, and reduced oviposition of T. urticae. Single regression analyses showed that a logistic model best explained the relationship between mortality or repellence and acylsucrose content, whereas a negative-exponential model best described the relationship between oviposition and acylsucrose content. Linear models were the best-fits for the three resistance variables with trichome IV density. Probit analysis was used to estimate acylsucrose effective doses, and revealed that 31 and 10% of the RILs produced acylsucrose above the effective doses for 90% mortality or repellence, respectively. Altogether, these results indicate that S. pimpinellifolium may be a suitable genetic source of resistance to spider mites to be used in cultivated tomato.

  14. Mites and allergy.

    Science.gov (United States)

    Fernández-Caldas, Enrique; Puerta, Leonardo; Caraballo, Luis

    2014-01-01

    Allergic diseases triggered by mite allergens include allergic rhinoconjunctivitis, asthma, atopic dermatitis and other skin diseases. Since the early discovery of the allergenic role of mites of the genus Dermatophagoides in the mid 1960s, numerous species have been described as the source of allergens capable of sensitizing and inducing allergic symptoms in sensitized and genetically predisposed individuals. The main sources of allergens in house dust worldwide are the fecal pellets of the mite species D. pteronyssinus, D. farinae, Euroglyphus maynei and the storage mites Blomia tropicalis, Lepidoglyphus destructor and Tyropahgus putrescentiae. Group 1 and 2 allergens are major house dust mite allergens. The main allergens in storage mites include fatty acid-binding proteins, tropomyosin and paramyosin homologues, apolipophorin-like proteins, α-tubulins and others, such as group 2, 5 and 7 allergens. Cross-reactivity is an important and common immunological feature among mites. Currently, purified native or recombinant allergens, epitope mapping, proteomic approaches and T cell proliferation techniques are being used to assess cross-reactivity. Mites contain potent enzymes capable of degrading a wide range of substrates. Most mite allergens are enzymes. Advances in genomics and molecular biology will improve our ability to understand the genetics of specific IgE responses to mites. Mite allergen avoidance and immunotherapy are the only two allergen-specific ways to treat mite-induced respiratory and cutaneous diseases. © 2014 S. Karger AG, Basel.

  15. Determinación del límite de rotura de un cable por Método de los Elementos Finitos. // Determination of resistance load on steel wire rope by Finite Elements Method.

    Directory of Open Access Journals (Sweden)

    F. Aguilar Parés

    2008-09-01

    Full Text Available En ocasiones, se desconocen las características originales de un cable de acero. En estos casos, generalmente se estima ellímite de rotura de un cable a partir del límite de rotura de un alambre del cable. En el presente trabajo, se propone emplearun método para estimar el límite de rotura del cable en base al modelado del cordón mediante elementos finitos. En elcontenido se explica detalladamente el procedimiento y es ejemplificado. El procedimiento es iniciado con el dibujo delcable en un programa de diseño gráfico parámetrico y posteriormente se describen las características generales delmodelado con un programa especializado en el Método de Elementos Finitos. En el análisis se incluye la influencia delcontacto entre los alambres que forman el cordón. Por último, se comparan los resultados obtenidos para el límite de roturadel cable con los datos declarados por el fabricante. Con este procedimiento fueron obtenidos valores mediante modeladodel cable con diferencias entre el 11% al 2,5% en relación al límite de rotura declarado por los fabricantes. Las diferenciasfueron evidenciadas en dependencia de la calidad del mallado empleado.Palabras claves: Cables de acero, elementos finitos, carga límite de rotura._________________________________________________________________________Abstract:In occasions, the original characteristics of steel wire rope are unknown. In these cases, could be estimated the resistanceof the wire rope knowing the wire resistance. In this proposal method for estimating the resistance load of steel wire thecord of the wire rope is modelling using finite elements. Procedure is explained and a sample with a selected wire rope ispresented. It is started with the drawing of the wire rope by professional software. General characteristics of themodelling are described with FEM software. In the analysis, the contact influence in the wires of the cord is included.Lastly, the obtained results of the resistance

  16. Flange Curling in Cold Formed Profiles

    DEFF Research Database (Denmark)

    Jönsson, Jeppe; Ramonas, Gediminas

    2012-01-01

    The non-linear flange curling phenomenon in cold formed profiles is the tendency of slender flanges to deform towards the neutral axis for increasing flexural curvature. Based on Braziers work, Winter proposed a simple engineering formula for determination of the local flange deformation towards...

  17. [Control strategies against Varroa mites].

    Science.gov (United States)

    Lodesani, M

    2004-06-01

    In many cases, the easiest way to control a pest or a pathogen is to resort to chemical treatments. In the short period this option is often the most convenient economically and usually does not require refined knowledge of the biology of the pest. Many efforts have been directed to develop chemical treatments against Varroa destructor Anderson & Trueman. Nowadays, product based on organic acids, essential oils, pyrethroids, organophosphate, and formamidine are available. Resistance is serious problem in the chemotherapy of parasites and pathogens of the honeybee. High-level resistance to several active substances (the pyrethroids acrinathrin, flumethrin, fluvalinate; the organophosphate coumaphos; the formamidine amitraz) was detected with laboratory assays in different varroa populations and caused failure of the control in the field. At the end of the '80s, products based on pyrethroids, very effective against the mite, but without any appreciable side effect on bees, became available. Resistance to fluvalinate in Italy and later in other countries caused serious damage to beekeeping; early detection was crucial to reduce losses. The problem of developing suitable treatments was difficult in the case of the varroa mite because most substances active against V. destructor have unacceptable side effects on bees. The idea that the mite could be controlled indefinitely with these strategies began to gain ground.

  18. Limited field establishment of a weed biocontrol agent, Floracarus perrepae (Acariformes: Eriophyidae), against Old World climbing fern in Florida--a possible role of mite resistant plant genotypes.

    Science.gov (United States)

    Boughton, Anthony J; Pemberton, Robert W

    2011-12-01

    The leaflet galling mite Floracarus perrepae Knihinicki & Boczek was released on Lygodium microphyllum (Cav.) in 63 plots in Florida from 2008 to 2009. Mites transferred onto field plants in 34 plots, but failed to establish populations in the majority of plots. Leaflet galls were observed in only six plots, and in only two plots did mite populations persist for >12 mo. Rates of mite transfer onto field plants were similar for methods using direct transfer of galls versus approaches using passive transfer of mites from infested plants. Often leaflets on some L. microphyllum plants were heavily galled by F. perrepae, whereas leaflets on intertwined stems of other L. microphyllum plants were ungalled but exhibited a characteristic browning and scorching of the leaflet tips. Living mites were consistently present on the undersurface of scorched leaflet tips on ungalled plants, suggesting that this damage might be caused by mite feeding on L. microphyllum genotypes that did not support induction of leaflet galls. Plant nutritional status did not account for differences in galling response, because there were no differences in leaflet nitrogen between galled and ungalled stems. We review those factors known to affect the colonization of biological control agents, and discuss how they may have contributed to the lower than expected rate of F. perrepae establishment.

  19. First detection of chlorfenapyr (Secure) resistance in two-spotted spider mite (Acari: Tetranychidae) from nectarines in an Australian orchard.

    Science.gov (United States)

    Herron, G A; Rophail, J

    2003-01-01

    Chlorfenapyr resistance (2.9- and 19.9-fold respectively at LC50 and LC99 level) was detected in Tetranychus urticae Koch causing control failure following a single application of product to nectarines.

  20. Deformation behavior of curling strips on tearing tubes

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Ji Won; Kwon, Tae Soo; Jung, Hyun Seung; Kim, Jin Sung [Dept. of Robotics and Virtual Engineering, Korea University of Science and Technology, Seoul (Korea, Republic of)

    2015-10-15

    This paper discusses the analysis of the curl deformation behavior when a dynamic force is applied to a tearing tube installed on a flat die to predict the energy absorption capacity and deformation behavior. The deformation of the tips of the curling strips was obtained when the curl tips and tube body are in contact with each other, and a formula describing the energy dissipation rate caused by the deformation of the curl tips is proposed. To improve this formula, we focused on the variation of the curl radius and the reduced thickness of the tube. A formula describing the mean curl radius is proposed and verified using the curl radius measurement data of collision test specimens. These improved formulas are added to the theoretical model previously proposed by Huang et al. and verified from the collision test results of a tearing tube.

  1. Preparation of Curled Micro bers by Electrospinning with Tip Collector

    Institute of Scientific and Technical Information of China (English)

    TANG Cheng-Chun; CHEN Jun-Chi; LONG Yun-Ze; YIN Hong-Xing; SUN Bin; ZHANG Hong-Di

    2011-01-01

    We report on curled polyvinylpyrrolidone (PVP) microfibers fabricated by a modified electrospinning with a small nail as the tip collector. PVP (45 wt%) ethanol solution is electrospun under different working voltages ranging from 10 to 15, 20, 30 and 40kV. It is found that with the increase of working voltage, the proportion of the curled fibers increases and the uniformity of the curled fibers improves, as well as the repeat distance of the curled structures reducing. Particularly, some curled fibers develop into helical structures under relatively high voltages. Further analyses indicate that the formation mechanism for the curled polymer fibers can be ascribed to electrical driven bending instability and/or mechanical jet buckling when hitting the collector surface. This modified electrospinning technique may be a cost-effective approach for the mass production of curled microfibers.%@@ We report on curled polyvinylpyrrolidone(PVP) microfibers fabricated by a modified electrospinning with a small nail as the tip collector.PVP(45 wt%) ethanol solution is electrospun under different working voltages ranging from 10 to 15,20,30 and 40kV.It is found that with the increase of working voltage,the proportion of the curled fibers increases and the uniformity of the curled fibers improves,as well as the repeat distance of the curled structures reducing.Particularly,some curled fibers develop into helical structures under relatively high voltages.Further analyses indicate that the formation mechanism for the curled polymer fibers can be ascribed to electrical driven bending instability and/or mechanical jet buckling when hitting the collector surface.This modified electrospinning technique may be a cost-effective approach for the mass production of curled microfibers.

  2. Age and reproductive status of adult Varroa mites affect grooming success of honey bees.

    Science.gov (United States)

    Kirrane, Maria J; de Guzman, Lilia I; Rinderer, Thomas E; Frake, Amanda M; Wagnitz, Jeremy; Whelan, Pádraig M

    2012-12-01

    This study evaluated for the first time the grooming response of honey bees to Varroa mites of different ages and reproductive statuses in the laboratory. Plastic cages containing a section of dark comb and about 200 bees were inoculated with groups of four classes of mites: gravid, phoretic foundresses, phoretic daughters and a combination of gravid and phoretic foundress mites. Each cage received 20 mites belonging to one of these classes. Our results showed that, 1 day after mite inoculation, phoretic daughter mites were the most prone to grooming by honey bees with an average mite drop of 49.8 ± 2.6 %. The lowest mite drop was recorded for bees inoculated with phoretic foundresses (30.3 ± 3.6 %) but was comparable to bees inoculated with gravid mites (31.8 ± 3.8 %) and the combination of gravid and phoretic foundress mites (34.2 ± 3.2 %). No differences among mite types were detected during the second and third days of observation. Regardless of mite type, the highest mite drop was recorded on the first day (35 ± 2.1 %) compared to the drop for any subsequent day (grooming behaviour may increase our insight into the importance of grooming in mite resistance.

  3. Resistance to tomato yellow leaf curl virus-Thailand isolate (TYLCTHV-[2] and markers loci association in BC2F1 population from a cross between Seedathip 3 and a wild tomato, Solanum habrochaites ‘L06112’ clone no.1

    Directory of Open Access Journals (Sweden)

    Uraiwan Pongpayaklers

    2012-02-01

    Full Text Available The BC2F1 population from a cross between wild tomato, Solanum habrochaites ‘L06112’ and recurrent susceptiblevariety, Seedathip 3 was investigated for a resistance to Tomato yellow leaf curl Thailand virus (TYLCTHV-[2]. Five stemcuttings from each of the 196 lines were inoculated with TYLCTHV-[2] using viruliferous whiteflies as the inoculation vector.Disease response was recorded weekly intervals and scored for three weeks according to the severity of the symptoms. Thepresence of TYLCTHV-[2] was confirmed by enzyme-linked immunosorbent assay (ELISA at three weeks after inoculation.ELISA readings showed a normal distribution for the BC2F1 population ranging from 0.055 (resistant to 0.930 (susceptible.DNA samples from BC2F1 population were analyzed for genes and markers association; Ty-2 on chromosome 11 using AVRDCprimer number 11-090.0 (TG105A, and Ty-3 on chromosome 6 using marker C2_At3g11210. Results showed that Ty-2 waslost during stepwise selection at BC1F1 generation, while Ty-3 showed no relationship to marker C2_At3g11210 and theamount of virus detected from ELISA reading. This indicated that the TYLCTHV-[2] resistant phenotype response in theBC2F1 population neither came from Ty-2 nor linked to the Ty-3 gene.

  4. Genetic analysis and cross-resistance spectrum of a laboratory-selected chlorfenapyr resistant strain of two-spotted spider mite (Acari: Tetranychidae).

    Science.gov (United States)

    Van Leeuwen, Thomas; Stillatus, Vincent; Tirry, Luc

    2004-01-01

    A laboratory susceptible strain of Tetranychus urticae was selected with chlorfenapyr resulting in a resistant strain. After 12 cycles of exposure, the resistance ratio (RR) calculated from the LC50s of susceptible and selected strain was 580. The resistant strain was screened with 16 currently used acaricides for cross-resistance. Cross-resistance was detected with amitraz (RR = 19.1), bifenthrin (RR = 1.3), bromopropylate (RR = 7.5), clofentezine (RR = 29.6) and dimethoate (RR = 17.6). No cross-resistance was detected with the new molecules acequinocyl, bifenazate and spirodiclofen. Mortality caused by chlorfenapyr in the F1 progeny from reciprocal crosses between both strains indicated that the mode of inheritance was incomplete recessive. Mortality in F2 progeny indicated that the resistance was under the control of more than one gene. Synergist experiments with S,S,S-tributylphosphorotrithioate (DEF), piperonylbutoxide (PBO) and diethylmaleate (DEM), which are inhibitors of esterases, monooxygenases and glutathion-S-transferases respectively, suggested a major role of esterases in the resistance to chlorfenapyr.

  5. H(curl) Auxiliary Mesh Preconditioning

    Energy Technology Data Exchange (ETDEWEB)

    Kolev, T V; Pasciak, J E; Vassilevski, P S

    2006-08-31

    This paper analyzes a two-level preconditioning scheme for H(curl) bilinear forms. The scheme utilizes an auxiliary problem on a related mesh that is more amenable for constructing optimal order multigrid methods. More specifically, we analyze the case when the auxiliary mesh only approximately covers the original domain. The latter assumption is important since it allows for easy construction of nested multilevel spaces on regular auxiliary meshes. Numerical experiments in both two and three space dimensions illustrate the optimal performance of the method.

  6. Computed tomography of ball pythons (Python regius) in curled recumbency.

    Science.gov (United States)

    Hedley, Joanna; Eatwell, Kevin; Schwarz, Tobias

    2014-01-01

    Anesthesia and tube restraint methods are often required for computed tomography (CT) of snakes due to their natural tendency to curl up. However, these restraint methods may cause animal stress. The aim of this study was to determine whether the CT appearance of the lungs differs for ball pythons in a curled position vs. tube restraint. Whole body CT was performed on ten clinically healthy ball pythons, first in curled and then in straight positions restrained in a tube. Curved multiplanar reformatted (MPR) lung images from curled position scans were compared with standard MPR lung images from straight position scans. Lung attenuation and thickness were measured at three locations for each scan. Time for positioning and scanning was 12 ± 5 min shorter for curled snakes compared to tube restraint. Lung parenchyma thickness and attenuation declined from cranial to caudal on both straight and curled position images. Mean lung parenchyma thickness was greater in curled images at locations 1 (P = 0.048) and 3 (P = 0.044). Mean lung parenchyma thickness decreased between location 1 and 2 by 86-87% (straight: curled) and between location 1 and 3 by 51-50% (straight: curled). Mean lung attenuation at location 1 was significantly greater on curled position images than tube restraint images (P = 0.043). Findings indicated that CT evaluation of the lungs is feasible for ball pythons positioned in curled recumbency if curved MPR is available. However, lung parenchyma thickness and attenuation in some locations may vary from those acquired using tube restraint.

  7. Influence of Varroa Mite (Varroa destructor) Management Practices on Insecticide Sensitivity in the Honey Bee (Apis mellifera)

    OpenAIRE

    Rinkevich, Frank D.; Danka, Robert G.; Kristen B. Healy

    2017-01-01

    Since Varroa mites may cause devastating losses of honey bees through direct feeding, transmitting diseases, and increasing pathogen susceptibility, chemical and mechanical practices commonly are used to reduce mite infestation. While miticide applications are typically the most consistent and efficacious Varroa mite management method, miticide-induced insecticide synergism in honey bees, and the evolution of resistance in Varroa mites are reasonable concerns. We treated colonies with the mit...

  8. Population growth of Varroa destructor (Acari: Varroidae) in colonies of Russian and unselected honey bee (Hymenoptera: Apidae) stock as related to numbers of foragers with mites

    Science.gov (United States)

    Varroa mites are an external parasite of honey bees and a leading cause of colony losses worldwide. Varroa populations can be controlled with miticides, but mite resistant stocks such as the Russian honey bee (RHB) also are available. RHB and other mite resistant stock limit Varroa population growth...

  9. A specific PCR-assay for resistance to Biotypes 1 and 2 of the rosy leaf curling aphid in apple based on an RFLP marker closely linked to the Sd1 gene

    NARCIS (Netherlands)

    Roche, P.; Arkel, van G.; Heusden, van A.W.

    1997-01-01

    This report describes the conversion of a restriction fragment length polymorphism (RFLP) marker (the 2B12a locus), linked to the Sd1 aphid resistance gene, to a polymerase chain reaction (PCR) based marker. A section of the 2B12 probe was sequenced and two primers were designed to amplify this

  10. A specific PCR-assay for resistance to Biotypes 1 and 2 of the rosy leaf curling aphid in apple based on an RFLP marker closely linked to the Sd1 gene

    NARCIS (Netherlands)

    Roche, P.; Arkel, van G.; Heusden, van A.W.

    1997-01-01

    This report describes the conversion of a restriction fragment length polymorphism (RFLP) marker (the 2B12a locus), linked to the Sd1 aphid resistance gene, to a polymerase chain reaction (PCR) based marker. A section of the 2B12 probe was sequenced and two primers were designed to amplify this sequ

  11. Cotton Leaf Curl Virus: lonic Status of Leaves and Symptom Development

    Institute of Scientific and Technical Information of China (English)

    Naeem Iqbal; Muhammad Yasin Ashraf; Farrukh Javed; Muhammad Ashraf; Sohail Hameed

    2006-01-01

    In the present study, the relationship between the nutritional status of leaves and the development of symptoms of cotton leaf curl virus (CLCuV) in two cotton (Gossypium hirsutum L.) cultivars (i.e. CIM-240 and S-12) was investigated. The incidence of disease attack was found to be 100% in the S-12 cultivar and 16% in the CIM-240 cultivar. Geminivirus particles in infected leaves were confirmed by transmission electron microscope examination of highly specific geminivirus coat protein antisera-treated cell sap. The CLCuV impaired the accumulation of different nutrients in both cultivars. A marked decrease in the accumulation of Ca2+ and K+ was observed in infected leaves. However, the disease had no effect on leaf concentrations of Na+, N, and P. It was observed that the curling of leaf margins in CLCuV-infected plants was associated with the leaf Ca2+ content; leaf curling was severe in plants with a significant reduction in Ca2+ content.Moreover, leaf K+ content was found to be associated with resistance/susceptibility to CLCuV infection.

  12. THE SPORTS SCIENCE OF CURLING: A PRACTICAL REVIEW

    Directory of Open Access Journals (Sweden)

    John L. Bradley

    2009-12-01

    Full Text Available Curling is a sport played on ice in which two teams each deliver 8 granite stones towards a target, or 'house'. It is the only sport in which the trajectory of the projectile can be influenced after it has been released by the athlete. This is achieved by sweeping the ice in front of the stone to change the stone-ice friction and thereby enable to stone to travel further, curl more or stay straight. Hard sweeping is physically demanding. Different techniques of sweeping can also have different effects on the stone. This paper will review the current research behind sweeping a curling stone, outline the physiological demands of sweeping, the associated performance effects and suggest potential strategies of sweeping that can be used by both coaches and curling teams

  13. Purification of tomato yellow leaf curl geminivirus.

    Science.gov (United States)

    Luisoni, E; Milne, R G; Vecchiati, M

    1995-07-01

    Attempts were made to find a good purification procedure for tomato yellow leaf curl virus (TYLCV), a dangerous and continuously spreading whitefly-transmitted germinivirus, up to now only partially purified. Electron microscopy, serology and spectrophotometry were used to evaluate different procedures. The scheme finally adopted was the following: collect leaves and stems from Nicotiana benthamiana graft-infected 45-60 days previously (5-10 g/plant); homogenize with 0.5 M phosphate buffer pH 6 containing 2.5 mM NaEDTA, 10 mM Na2SO3, 0.1% 2-mercaptoethanol, 1% Triton X-100 and 0.1% Driselase (3-4 ml of buffer for each g of material); incubate overnight on ice with gentle agitation; filter; emulsify with 15% cold chloroform; centrifuge at low speed; ultracentrifuge supernatant; resuspend pellets in 0.5 M phosphate buffer pH 7 containing 2.5 mM NaEDTA; centrifuge at low speed; repeat resuspension of the pellets and low-speed centrifugation; ultracentrifuge the pooled supernatant on a Cs2SO4 gradient (e.g. for 5 h at 41,000 rpm); collect the virus band and dialyse or ultracentrifuge the virus. The virus yield was 5-10 mg per kg of tissue.

  14. Pepper leaf curl Lahore virus requires the DNA B component of Tomato leaf curl New Delhi virus to cause leaf curl symptoms

    Directory of Open Access Journals (Sweden)

    Briddon Rob W

    2010-12-01

    Full Text Available Abstract Background Begomoviruses are whitefly-transmitted geminiviruses with genomes that consist of either two components (known as DNA A and DNA B or a single component (homologous to the DNA A component of bipartite begomoviruses. Monopartite begomoviruses are often associated with a symptom-modulating DNA satellite (collectively known as betasatellites. Both bipartite and monopartite begomoviruses with associated satellites have previously been identified in chillies showing leaf curl symptoms in Pakistan. Results A chilli plant (Capsicum annum with chilli leaf curl disease symptoms was found to contain a begomovirus, a betasatellite and the DNA B component of Tomato leaf curl New Delhi virus (ToLCNDV. The begomovirus consisted of 2747 nucleotides and had the highest sequence identity (99% with Pepper leaf curl Lahore virus (PepLCLV-[PK: Lah:04], acc. no. AM404179. Agrobacterium-mediated inoculation of the clone to Nicotiana benthamiana, induced very mild symptoms and low levels of viral DNA, detected in systemically infected leaves by PCR. No symptoms were induced in Nicotiana tabacum or chillies either in the presence or absence of a betasatellite. However, inoculation of PepLCLV with the DNA B component of ToLCNDV induced leaf curl symptoms in N. benthamiana, N. tabacum and chillies and viral DNA accumulated to higher levels in comparison to plants infected with just PepLCLV. Conclusions Based on our previous efforts aimed at understanding of diversity of begomoviruses associated with chillies, we propose that PepLCLV was recently mobilized into chillies upon its interaction with DNA B of ToLCNDV. Interestingly, the putative rep-binding iterons found on PepLCLV (GGGGAC differ at two base positions from those of ToLCNDV (GGTGTC. This is the first experimental demonstration of the infectivity for a bipartite begomovirus causing chilli leaf curl disease in chillies from Pakistan and suggests that component capture is contributing to the

  15. Mapping of QTLs Conferring the Resistance to Tomato Yellow Leaf Curl Virus(TYLCV)in Solanum lycopersicoides%类番茄茄抗番茄黄花曲叶病毒QTL的定位

    Institute of Scientific and Technical Information of China (English)

    宗园园; 刘磊; 李涛; Sayed Rashad Ali Shah; 周龙溪; 孙玉燕; 郑峥; 郑启功; 范淑英; 李君明

    2012-01-01

    An introgression line(IL)population,which was derived from a wild relative Solanum lycopersicoides LA2951,was used to screen the involved loci for resistance to TYLCV by the natural inoculation. In total,7 QTLs conferring the resistance to TYLCV were identified after the analysis of different individuals of IL population,which were respectively located on chromosome 1,3,4,5,6, 7 and 12. Among them,QTL involved in chromosome 1 still need to be addressed further.%采用田间自然接种番茄黄花曲叶病毒(TYLCV)的鉴定方法,对来自番茄野生种类番茄茄Solanum.lycopersicoides LA2951的渐渗系(Introgression Line,IL)群体进行了筛选,发现类番茄茄LA2951对TYLCV的抗性受多个位点控制。通过分析不同IL的抗性,共鉴定出7个QTL,分别位于染色体1、3、4、5、6、7和12上,其中位于染色体1上的QTL有待于进一步确定。

  16. Allergens of mites

    Directory of Open Access Journals (Sweden)

    Emilia Siwak

    2014-04-01

    Full Text Available Mite allergens belong to the group of inhalant allergens and represent antigenic substances which are particutlarly important in the pathogenesis of respiratory system diseases and skin diseases. The most common diseases associated with chronic exposure to these aeroallergens include: allergic rhinitis, bronchial asthma and atopic dermatitis. Mite allergens are simple proteins or glycoproteins with different molecular structures and various biochemical functions. The sensitizing capacity of these proteins is connected from their physicochemical properties. Individual allergens perform, among others, the functions of structural proteins, act as enzymes, transport lipids, bind metal ions, and are capable of glycosylation. In addition, mite allergenic proteases degrade proteins of the skin epithelium-resulting in a weakening of its natural protective barrier-and induce the immune response. The proteases also induce the release of pro-inflammatory cytokines: interleukin-4 (IL-4, interleukin 6 (IL-6, interleukin 8 (IL-8, eotaxin, and granulocyte-macrophage colony-stimulating factor-GM-CSF. The article presents the tertiary structure of major and mid-range mite allergens and their classification. Based on literature reports concerning the chemical structure of allergenic proteins, it was emphasized that the structural differences between homologous proteins with allergenic pozoproperties relate to the distribution of amino acid residues on the surface of the molecule. IgE binding affinity and the similarities and differences in the amino acid sequence of the allergens were also the basis for determining cross-reactivity of allergenic proteins. The paper shows an example of this phenomenon, describing the existence of common allergens for various mite species.

  17. [House dust mite allergy].

    Science.gov (United States)

    Carrard, A; Pichler, C

    2012-04-01

    House dust mites can be found all over the world where human beings live independent from the climate. Proteins from the gastrointestinal tract- almost all known as enzymes - are the allergens which induce chronic allergic diseases. The inhalation of small amounts of allergens on a regular base all night leads to a slow beginning of the disease with chronically stuffed nose and an exercise induced asthma which later on persists. House dust mites grow well in a humid climate - this can be in well isolated dwellings or in the tropical climate - and nourish from human skin dander. Scales are found in mattresses, upholstered furniture and carpets. The clinical picture with slowly aggravating complaints leads quite often to a delayed diagnosis, which is accidently done on the occasion of a wider spectrum of allergy skin testing. The beginning of a medical therapy with topical steroids as nasal spray or inhalation leads to a fast relief of the complaints. Although discussed in extensive controversies in the literature - at least in Switzerland with the cold winter and dry climate - the recommendation of house dust mite avoidance measures is given to patients with good clinical results. The frequent ventilation of the dwelling with cold air in winter time cause a lower indoor humidity. Covering encasings on mattresses, pillow, and duvets reduces the possibility of chronic contact with mite allergens as well as the weekly changing the bed linen. Another option of therapy is the specific immunotherapy with extracts of house dust mites showing good results in children and adults. Using recombinant allergens will show a better quality in diagnostic as well as in therapeutic specific immunotherapy.

  18. A New Cherry Tomato'Jinling Tianyu'with Resistance to Tomato Yellow Leaf Curl Virus%抗番茄黄化曲叶病毒病樱桃番茄新品种‘金陵甜玉’

    Institute of Scientific and Technical Information of China (English)

    赵统敏; 余文贵; 杨玛丽; 赵丽萍

    2011-01-01

    ‘金陵甜玉’樱桃番茄是以TY-07-5为母本,TY-07-4为父本育成的无限生长类型一代杂种,生长势较强,叶色深绿,果实短椭圆形,成熟果红色,果皮厚,耐贮运,单果质量22g左右,抗番茄黄化曲叶病毒病,抗ToMV和枯萎病。%'Jinling Tianyu'is a new cherry tomato hybrid which developed by crossing TY-07-5 as a female parent with TY-07-4 as a male parent.It is indeterminate growth type,which grows vigorously.The leaf is dark green.The fruit is red,and it has oval-round shape.The average weight of single fruit is 22 g.It is resistant to TYLCV,ToMV and wilt.

  19. Increased transcription of Glutathione S-transferases in acaricide exposed scabies mites

    Directory of Open Access Journals (Sweden)

    Currie Bart J

    2010-05-01

    Full Text Available Abstract Background Recent evidence suggests that Sarcoptes scabiei var. hominis mites collected from scabies endemic communities in northern Australia show increasing tolerance to 5% permethrin and oral ivermectin. Previous findings have implicated detoxification pathways in developing resistance to these acaricides. We investigated the contribution of Glutathione S-transferase (GST enzymes to permethrin and ivermectin tolerance in scabies mites using biochemical and molecular approaches. Results Increased in vitro survival following permethrin exposure was observed in S. scabiei var. hominis compared to acaricide naïve mites (p in vitro permethrin susceptibility, confirming GST involvement in permethrin detoxification. Assay of GST enzymatic activity in mites demonstrated that S. scabiei var. hominis mites showed a two-fold increase in activity compared to naïve mites (p S. scabiei var. canis- mu 1 (p S. scabiei var. hominis mites collected from a recurrent crusted scabies patient over the course of ivermectin treatment. Conclusions These findings provide further support for the hypothesis that increased drug metabolism and efflux mediate permethrin and ivermectin resistance in scabies mites and highlight the threat of emerging acaricide resistance to the treatment of scabies worldwide. This is one of the first attempts to define specific genes involved in GST mediated acaricide resistance at the transcriptional level, and the first application of such studies to S. scabiei, a historically challenging ectoparasite.

  20. Control of poultry red mites

    DEFF Research Database (Denmark)

    Kilpinen, Ole; Steenberg, Tove

    2008-01-01

    The poultry red mite (PRM), Dermanyssus gallinae, is the most important ectoparasite in European egg production. The mites hide in cracks and crevices in the near vicinity of the resting places of the birds, coming out to feed mainly during the night. Under favourable conditions the population can...... grow rapidly, leading to serious problems. Large mite populations may cause anaemia or even death to the poultry, but also in lower numbers mites may be a nuisance to the birds causing decreased egg production and egg quality. Furthermore, they may have the potential of acting as reservoir...

  1. Regular dorsal dimples and damaged mites of Varroa destructor in some Iranian honey bees (Apis mellifera).

    Science.gov (United States)

    Ardestani, Masoud M; Ebadi, Rahim; Tahmasbi, Gholamhossein

    2011-07-01

    The frequency of damaged Varroa destructor Anderson and Trueman (Mesostigmata: Varroidae) found on the bottom board of hives of the honey bee, Apis mellifera L. (Hymenoptera: Apidae) has been used as an indicator of the degree of tolerance or resistance of honey bee colonies against mites. However, it is not clear that this measure is adequate. These injuries should be separated from regular dorsal dimples that have a developmental origin. To investigate damage to Varroa mites and regular dorsal dimples, 32 honey bee (A. mellifera) colonies were selected from four Iranian provinces: Isfahan, Markazi, Qazvin, and Tehran. These colonies were part of the National Honey bee Breeding Program that resulted in province-specific races. In April, Varroa mites were collected from heavily infested colonies and used to infest the 32 experimental colonies. In August, 20 of these colonies were selected (five colonies from each province). Adult bees from these colonies were placed in cages and after introducing mites, damaged mites were collected from each cage every day. The average percentage of injured mites ranged from 0.6 to 3.0% in four provinces. The results did not show any statistical differences between the colonies within provinces for injuries to mites, but there were some differences among province-specific lines. Two kinds of injuries to the mites were observed: injuries to legs and pedipalps, and injuries to other parts of the body. There were also some regular dorsal dimples on dorsal idiosoma of the mites that were placed in categories separate from mites damaged by bees. This type of classification helps identifying damage to mites and comparing them with developmental origin symptoms, and may provide criteria for selecting bees tolerant or resistant to this mite.

  2. Parasitic mites of Surinam XXXIII. Feather mites (Analgoidea)

    NARCIS (Netherlands)

    Černý, V.; Lukoschus, F.S.

    1975-01-01

    The mites listed in the present paper have been collected from July to October 1971 by the junior author and Drs. N. J. J. KOK during their stay in Surinam with financial aid of the Netherlands Foundation for the Advancement of Tropical Research (WOTRO). Mites have been collected occasionally mainly

  3. The complete nucleotide sequence of pelargonium leaf curl virus.

    Science.gov (United States)

    McGavin, Wendy J; MacFarlane, Stuart A

    2016-05-01

    Investigation of a tombusvirus isolated from tulip plants in Scotland revealed that it was pelargonium leaf curl virus (PLCV) rather than the originally suggested tomato bushy stunt virus. The complete sequence of the PLCV genome was determined for the first time, revealing it to be 4789 nucleotides in size and to have an organization similar to that of the other, previously described tombusviruses. Primers derived from the sequence were used to construct a full-length infectious clone of PLCV that recapitulates the disease symptoms of leaf curling in systemically infected pelargonium plants.

  4. Acaricidal activity of eugenol based compounds against scabies mites.

    Directory of Open Access Journals (Sweden)

    Cielo Pasay

    Full Text Available BACKGROUND: Human scabies is a debilitating skin disease caused by the "itch mite" Sarcoptes scabiei. Ordinary scabies is commonly treated with topical creams such as permethrin, while crusted scabies is treated with topical creams in combination with oral ivermectin. Recent reports of acaricide tolerance in scabies endemic communities in Northern Australia have prompted efforts to better understand resistance mechanisms and to identify potential new acaricides. In this study, we screened three essential oils and four pure compounds based on eugenol for acaricidal properties. METHODOLOGY/PRINCIPAL FINDINGS: Contact bioassays were performed using live permethrin-sensitive S. scabiei var suis mites harvested from pigs and permethrin-resistant S. scabiei var canis mites harvested from rabbits. Results of bioassays showed that clove oil was highly toxic against scabies mites. Nutmeg oil had moderate toxicity and ylang ylang oil was the least toxic. Eugenol, a major component of clove oil and its analogues--acetyleugenol and isoeugenol, demonstrated levels of toxicity comparable to benzyl benzoate, the positive control acaricide, killing mites within an hour of contact. CONCLUSIONS: The acaricidal properties demonstrated by eugenol and its analogues show promise as leads for future development of alternative topical acaricides to treat scabies.

  5. Influence of cutting conditions on chip side curl

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    2004-01-01

    The paper describes the influence of local variations of contact length, cutting speed and material constraint, showing the effect of lubrication, on the side curl of the chip. The following examples are illustrated by experiments: cutting of a tube vs. cutting of a bar; cutting using a tool...

  6. Influence of cutting conditions on chip side curl

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    2004-01-01

    The paper describes the influence of local variations of contact length, cutting speed and material constraint, showing the effect of lubrication, on the side curl of the chip. The following examples are illustrated by experiments: cutting of a tube vs. cutting of a bar; cutting using a tool with...

  7. Computation of Surface Integrals of Curl Vector Fields

    Science.gov (United States)

    Hu, Chenglie

    2007-01-01

    This article presents a way of computing a surface integral when the vector field of the integrand is a curl field. Presented in some advanced calculus textbooks such as [1], the technique, as the author experienced, is simple and applicable. The computation is based on Stokes' theorem in 3-space calculus, and thus provides not only a means to…

  8. Transmission of Sweet Potato Leaf Curl Virus by Bemisia tabaci

    Science.gov (United States)

    Sweetpotato, Ipomoea batatas (L.) Lam. (Solanales: Convolvulaceae), is an important world food crop, and Asia is the focal production region. Because it is vegetatively propagated, sweetpotato is especially prone to accumulate infections by several viruses. Sweet potato leaf curl virus (SPLCV) (ss...

  9. New developments in insecticide resistance in the glasshouse whitefly (Trialeurodes vaporariorum) and the two-spotted spider mite (Tetranychus urticae) in the UK.

    Science.gov (United States)

    Gorman, Kevin; Hewitt, Fiona; Denholm, Ian; Devine, Gregor J

    2002-02-01

    A recent survey of insecticide resistance in two of the most problematic pests in UK glasshouses revealed some new developments. At least some individuals in all UK samples of Trialeurodes vaporariorum that were tested resisted the insect growth regulator (IGR) buprofezin. The most strongly resistant strains were unaffected by the field application rate of this compound, and even samples from populations that had never been exposed to buprofezin contained individuals that survived the highest concentration applied (10,000 mg litre-1). The field rate of buprofezin was shown to select for resistance through vapour action alone. The benzophenylurea teflubenzuron, an unrelated IGR, was cross-resisted by buprofezin-resistant individuals. There was no evidence of resistance to imidacloprid, but all T vaporariorum strains tested, regardless of origin, exhibited a high innate tolerance to nicotine, when compared with another whitefly species, Bemisia tabaci. Marked resistance to fenbutatin oxide and tebufenpyrad was found in single glasshouse populations of Tetranychus urticae, but these compounds and abamectin appeared to remain highly effective against all other strains collected.

  10. Incidence and inheritance of resistance to METI-acaricides in European strains of the two-spotted spider mite (Tetranychus urticae) (Acari: Tetranychidae).

    Science.gov (United States)

    Devine, G J; Barber, M; Denholm, I

    2001-05-01

    A strain of Tetranychus urticae (Koch; Acari: Tetranychidae), collected from hops (Humulus humuli L; Cannabaceae) in England with a short history of tebufenpyrad use, exhibited resistance to four METI (mitochondrial electron transport inhibitor)-acaricides; tebufenpyrad, pyridaben, fenazaquin and fenpyroximate. Resistance factors for these compounds in a microimmersion assay were 46, 346, 168 and 77 respectively, and corresponded to those exhibited by a Japanese METI-acaricide-resistant reference strain. Levels of resistance remained stable without further selection, and selection with tebufenpyrad did not increase them. The UK strain was also resistant (c 6-fold) to bifenthrin. Crosses of homozygous, diploid females with hemizygous, haploid males showed that, in the UK strain, METI-acaricide resistance was paternally and maternally inherited, and was an incompletely dominant trait. Another tebufenpyrad-resistant strain from the UK, originating from a chrysanthemum nursery (Chrysanthemum foeniculaceum Giseke; Asteraceae) was collected eight months later at a site c 210 km distant from the first. These are the first published incidences of METI-acaricide resistance in Europe and implications for the future use of these compounds are discussed.

  11. The role of volatiles in aggregation and host-seeking of the haematophagous poultry red mite Dermanyssus gallinae (Acari: Dermanyssidae).

    Science.gov (United States)

    Koenraadt, C J M; Dicke, M

    2010-03-01

    Infestations with ectoparasitic poultry red mites (Dermanyssus gallinae) pose an increasing threat to poultry health and welfare. Because of resistance to acaricides and higher scrutiny of poultry products, alternative and environmentally safe management strategies are warranted. Therefore, we investigated how volatile cues shape the behavior of D. gallinae and how this knowledge may be exploited in the development of an attract-and-kill method to control mite populations. A Y-tube olfactometer bio-assay was used to evaluate choices of mites in response to cues related to conspecific mites as well as related to their chicken host. Both recently fed and starved mites showed a strong preference (84 and 85%, respectively) for volatiles from conspecific, fed mites as compared to a control stream of clean air. Mites were also significantly attracted to 'aged feathers' (that had remained in the litter for 3-4 days), but not to 'fresh feathers'. Interestingly, an air stream containing 2.5% CO(2), which mimics the natural concentration in air exhaled by chickens, did attract fed mites, but inhibited the attraction of unfed mites towards volatiles from aged feathers. We conclude that both mite-related cues (aggregation pheromones) and host-related cues (kairomones) mediate the behavior of the poultry mite. We discuss the options to exploit this knowledge as the 'attract' component of attract-and-kill strategies for the control of D. gallinae.

  12. Evaluation under diverse conditions of a differential host reaction scale to Tomato yellow leaf curl virus in tomato

    Directory of Open Access Journals (Sweden)

    Ana PÉREZ-DE-CASTRO

    2017-05-01

    Full Text Available Tomato yellow leaf curl virus (TYLCV is the most widespread virus species causing Tomato yellow leaf curl disease. Accurate methods for assessment of resistance are requisite in breeding programs. Researchers at the Volcani Center (Israel developed a scale of differential TYLCV reactions in seven non-segregating tomato host lines, with virus responses ranging from susceptible to highly resistant. In the present work, this scale has been evaluated with inoculation and assessment methods routinely used by two different research groups, in Spain and Cuba. Different TYLCV isolates, inoculation methods, plant ages, and environmental conditions were compared. Symptom scores of the tomato lines were generally lower in the conditions assayed in both locations than those originally described. Reaction ranking order of the standard tomato lines was more similar to the original description in the assays carried out in Spain. However, response of the lines to TYLCV obtained in both locations did not correspond to scale grades for most of the conditions. A large difference between symptom scores in the susceptible and the resistant lines was observed, with the range in the resistant lines being narrow. These results indicate that the number of standard lines used could be reduced, selecting the most susceptible and the most resistant lines, and one with intermediate resistance. All the factors evaluated affected symptom development. This highlights the importance of establishing a standard inoculation method, experimental conditions, evaluation period and appropriate resistance evaluation criteria, to ensure precise evaluation of genotype responses.

  13. MicroRNA profiling of tomato leaf curl new delhi virus (tolcndv infected tomato leaves indicates that deregulation of mir159/319 and mir172 might be linked with leaf curl disease

    Directory of Open Access Journals (Sweden)

    Haq Qazi MR

    2010-10-01

    Full Text Available Abstract Background Tomato leaf curl virus (ToLCV, a constituent of the genus Begomovirus, infects tomato and other plants with a hallmark disease symptom of upward leaf curling. Since microRNAs (miRs are known to control plants developmental processes, we evaluated the roles of miRNAs in Tomato leaf curl New Delhi virus (ToLCNDV induced leaf curling. Results Microarray analyses of miRNAs, isolated from the leaves of both healthy and ToLCNDV agroinfected tomato cv Pusa Ruby, revealed that ToLCNDV infection significantly deregulated various miRNAs representing ~13 different conserved families (e.g., miR319, miR172, etc.. The precursors of these miRNAs showed similar deregulated patterns, indicating that the transcription regulation of respective miRNA genes was perhaps the cause of deregulation. The expression levels of the miRNA-targeted genes were antagonistic with respect to the amount of corresponding miRNA. Such deregulation was tissue-specific in nature as no analogous misexpression was found in flowers. The accumulation of miR159/319 and miR172 was observed to increase with the days post inoculation (dpi of ToLCNDV agroinfection in tomato cv Pusa Ruby. Similarly, these miRs were also induced in ToLCNDV agroinfected tomato cv JK Asha and chilli plants, both exhibiting leaf curl symptoms. Our results indicate that miR159/319 and miR172 might be associated with leaf curl symptoms. This report raises the possibility of using miRNA(s as potential signature molecules for ToLCNDV infection. Conclusions The expression of several host miRNAs is affected in response to viral infection. The levels of the corresponding pre-miRs and the predicted targets were also deregulated. This change in miRNA expression levels was specific to leaf tissues and observed to be associated with disease progression. Thus, certain host miRs are likely indicator of viral infection and could be potentially employed to develop viral resistance strategies.

  14. on control of the spider mite (Tetranychus urticae Koch.) in peanut

    African Journals Online (AJOL)

    Samson Edoja

    2016-07-27

    Jul 27, 2016 ... spp. are mites that cause damage to several crops and are primarily controlled by synthetic pesticides. Literature showed that ... increase pesticide resistance of insect-pests (Gill and ... way less aggressive to the environment.

  15. Molecular Characterization of Tomato leaf curl Palampur virus and Pepper leaf curl betasatellite Naturally Infecting Pumpkin (Cucurbita moschata) in India.

    Science.gov (United States)

    Namrata, Jaiswal; Saritha, R K; Datta, D; Singh, M; Dubey, R S; Rai, A B; Rai, M

    2010-10-01

    Pumpkin cultivation in India is affected by severe incidence of a yellow vein mosaic disease. Tomato leaf curl New Delhi virus and Squash leaf curl China virus are known to be associated with this disease in India. We were able to identify a third begomovirus-Tomato leaf curl Palampur virus (ToLCPMV), from pumpkin showing typical symptoms of the disease at Varanasi based on the sequence of complete DNA-A genome of the virus. The complete DNA-A sequence of the virus shared more than 99% sequence identity with other ToLCPMV isolates available in the GenBank and clustered with them in the phylogenetic analysis. This betasatellite amplified from the same infected sample has been identified as Pepper leaf curl betasatellite (PepLCB) which also infects chilli in India. There was 92% sequence identity between the two isolates. This is the first report of natural infection of ToLCPMV on pumpkin and association of PepLCB with yellow vein mosaic disease of pumpkin in India.

  16. Control of poultry red mites

    DEFF Research Database (Denmark)

    Kilpinen, Ole; Steenberg, Tove

    2008-01-01

    The poultry red mite (PRM), Dermanyssus gallinae, is the most important ectoparasite in European egg production. The mites hide in cracks and crevices in the near vicinity of the resting places of the birds, coming out to feed mainly during the night. Under favourable conditions the population can...... grow rapidly, leading to serious problems. Large mite populations may cause anaemia or even death to the poultry, but also in lower numbers mites may be a nuisance to the birds causing decreased egg production and egg quality. Furthermore, they may have the potential of acting as reservoir....../carriers for various micro-organisms e.g. Salmonella. In SAFEHOUSE, an EU-project running from 2006-2009, partners from 11 European countries aim at developing new methods for prevention and control of Salmonella in egg production systems with particular focus on the transition to enriched cages in the EU. Enriched...

  17. Flat acoustic lens by acoustic grating with curled slits

    Energy Technology Data Exchange (ETDEWEB)

    Peng, Pai; Xiao, Bingmu; Wu, Ying, E-mail: ying.wu@kaust.edu.sa

    2014-10-03

    We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry–Perot resonance. - Highlights: • Expression of transmission coefficient of an acoustic grating with curled slits. • Non-dispersive and tunable effective medium parameters for the acoustic grating. • A flat acoustic focusing lens with gradient index by using the acoustic grating.

  18. Cosmic Shear of the Microwave Background: The Curl Diagnostic

    CERN Document Server

    Cooray, A R; Caldwell, R R; Cooray, Asantha; Kamionkowski, Marc; Caldwell, Robert R.

    2005-01-01

    Weak-lensing distortions of the cosmic-microwave-background (CMB) temperature and polarization patterns can reveal important clues to the intervening large-scale structure. The effect of lensing is to deflect the primary temperature and polarization signal to slightly different locations on the sky. Deflections due to density fluctuations, gradient-type for the gradient of the projected gravitational potential, give a direct measure of the mass distribution. Curl-type deflections can be induced by, for example, a primordial background of gravitational waves from inflation or by second-order effects related to lensing by density perturbations. Whereas gradient-type deflections are expected to dominate, we show that curl-type deflections can provide a useful test of systematics and serve to indicate the presence of confusing secondary and foreground non-Gaussian signals.

  19. Curling Liquid Crystal Microswimmers: A Cascade of Spontaneous Symmetry Breaking

    Science.gov (United States)

    Krüger, Carsten; Klös, Gunnar; Bahr, Christian; Maass, Corinna C.

    2016-07-01

    We report curling self-propulsion in aqueous emulsions of common mesogenic compounds. Nematic liquid crystal droplets self-propel in a surfactant solution with concentrations above the critical micelle concentration while undergoing micellar solubilization [Herminghaus et al., Soft Matter 10, 7008 (2014)]. We analyzed trajectories both in a Hele-Shaw geometry and in a 3D setup at variable buoyancy. The coupling between the nematic director field and the convective flow inside the droplet leads to a second symmetry breaking which gives rise to curling motion in 2D. This is demonstrated through a reversible transition to nonhelical persistent swimming by heating to the isotropic phase. Furthermore, autochemotaxis can spontaneously break the inversion symmetry, leading to helical trajectories in 3D.

  20. [House dust mites and their allergens].

    Science.gov (United States)

    Bessot, J-C; Pauli, G

    2011-02-01

    The taxonomy, anatomy, life cycle and ecology of Pyroglyphidae mites and storage mites (Acaridae, Glycyphagidae, B. tropicalis) are described. Pyroglyphidae and storage mites have similar morphologies: they are octopods, with characteristic gnathosoma and sensory hairs. Salivary glands and the mid gut produce most of the allergens excreted, which are enzymatic proteins. Biological cycles and development are similar, although fecundity is superior in storage mites compared to the Pyroglyphides. Relative humidity is the main parameter, which regulates mite development, with a higher degree of temperature and humidity required for storage mites. Bedding is the ecological niche of Pyroglyphidae, which feed on human skin. Moulds and food products are the storage mite biotope from which they spread in the dwelling. Initially considered as rural mites, storage mites are also present in urban dwellings. B. tropicalis, in tropical regions is a true domestic mite. Because of this, it is justified to denominate Pyroglyphidae "house dust mites" and storage mites "domestic mites". In addition to the respiratory allergic symptoms, the storage mites can also cause occupational contact dermatoses.

  1. Effect of neck flexion restriction on sternocleidomastoid and abdominal muscle activity during curl-up exercises.

    Science.gov (United States)

    Lee, Dong-Kyu; Moon, Dong-Chul; Hong, Ki-Hoon

    2016-01-01

    [Purpose] The purpose of this study was to investigate the effect of neck flexion restriction on sternocleidomastoid (SCM), rectus abdominis (RA), and external oblique (EO) muscle activity during a traditional curl-up exercise and a curl-up with neck flexion restriction. [Subjects] In total, 13 healthy male subjects volunteered for this study. [Methods] All subjects performed a traditional curl-up exercise and a curl-up exercise in which neck flexion was restricted by the subject's hand. Surface electromyography (EMG) signals were recorded from the SCM, RA, and EO during the curl-up. [Results] There was significantly lower EMG activity of the SCM during the curl-up exercise with neck flexion restriction compared to the traditional curl-up exercise. Conversely, the activity of the RA and EO muscles was significantly higher in the curl-up exercise with neck flexion restriction than in the traditional curl-up exercise. [Conclusion] Neck flexion restriction is recommended to prevent excessive activation of superficial cervical flexors during the curl-up exercise.

  2. Analytical investigation into the resonance frequencies of a curling probe

    Science.gov (United States)

    Arshadi, Ali; Brinkmann, Ralf Peter

    2016-08-01

    The term ‘active plasma resonance spectroscopy’ (APRS) denotes a class of closely related plasma diagnostic methods which utilize the natural ability of plasmas to resonate on or near the electron plasma frequency {ω\\text{pe}} ; an electrical radio frequency signal (in the GHz range) is coupled into the plasma via an antenna or a probe, the spectral response is recorded and a mathematical model is employed to determine plasma parameters such as the plasma density and the electron temperature. The curling probe, recently invented by Liang et al (2011 Appl. Phys. Express 4 066101), is a novel realization of the APRS concept which has many practical advantages. In particular, it can be miniaturized and flatly embedded into the chamber wall, thus allowing the monitoring of plasma processes without contamination nor disturbance. Physically, the curling probe can be understood as a ‘coiled’ form of the hairpin probe (Stenzel 1976 Rev. Sci. Instrum. 47 603). Assuming that the spiralization of the probe has little electrical effect, this paper investigates the characteristcs of a ‘straightened’ curling probe by modeling it as an infinite slot-type resonator that is in direct contact with the plasma. The diffraction of an incident plane wave at the slot is calculated by solving the cold plasma model and Maxwell’s equations simultaneously. The resonance frequencies of the probe are derived and are found to be in good agreement with the numerical results of the probe inventors.

  3. Diversity, Mutation and Recombination Analysis of Cotton Leaf Curl Geminiviruses.

    Directory of Open Access Journals (Sweden)

    Huma Saleem

    Full Text Available The spread of cotton leaf curl disease in China, India and Pakistan is a recent phenomenon. Analysis of available sequence data determined that there is a substantial diversity of cotton-infecting geminiviruses in Pakistan. Phylogenetic analyses indicated that recombination between two major groups of viruses, cotton leaf curl Multan virus (CLCuMuV and cotton leaf curl Kokhran virus (CLCuKoV, led to the emergence of several new viruses. Recombination detection programs and phylogenetic analyses showed that CLCuMuV and CLCuKoV are highly recombinant viruses. Indeed, CLCuKoV appeared to be a major donor virus for the coat protein (CP gene, while CLCuMuV donated the Rep gene in the majority of recombination events. Using recombination free nucleotide datasets the substitution rates for CP and Rep genes were determined. We inferred similar nucleotide substitution rates for the CLCuMuV-Rep gene (4.96X10-4 and CLCuKoV-CP gene (2.706X10-4, whereas relatively higher substitution rates were observed for CLCuMuV-CP and CLCuKoV-Rep genes. The combination of sequences with equal and relatively low substitution rates, seemed to result in the emergence of viral isolates that caused epidemics in Pakistan and India. Our findings also suggest that CLCuMuV is spreading at an alarming rate, which can potentially be a threat to cotton production in the Indian subcontinent.

  4. Hydro-responsive curling of the resurrection plant Selaginella lepidophylla.

    Science.gov (United States)

    Rafsanjani, Ahmad; Brulé, Véronique; Western, Tamara L; Pasini, Damiano

    2015-01-27

    The spirally arranged stems of the spikemoss Selaginella lepidophylla, an ancient resurrection plant, compactly curl into a nest-ball shape upon dehydration. Due to its spiral phyllotaxy, older outer stems on the plant interlace and envelope the younger inner stems forming the plant centre. Stem curling is a morphological mechanism that limits photoinhibitory and thermal damages the plant might experience in arid environments. Here, we investigate the distinct conformational changes of outer and inner stems of S. lepidophylla triggered by dehydration. Outer stems bend into circular rings in a relatively short period of desiccation, whereas inner stems curl slowly into spirals due to hydro-actuated strain gradient along their length. This arrangement eases both the tight packing of the plant during desiccation and its fast opening upon rehydration. The insights gained from this work shed light on the hydro-responsive movements in plants and might contribute to the development of deployable structures with remarkable shape transformations in response to environmental stimuli.

  5. The CURL-CoFoR Collaborative Collection Management Project

    Directory of Open Access Journals (Sweden)

    Gregory Walker

    2005-09-01

    Full Text Available CoFoR originated from an initiative by CURL, the Consortium of Research Libraries in the British Isles. CURL’s Task Force on Resource Management proposed a project, which would develop and test several interrelated aspects of collaborative collection management (CCM, to help in determining the most effective kinds of collaboration between major research collections. The Task Force was concerned that local pressures on libraries were tending to make them take collection management decisions in isolation, and they were looking for a framework within which better informed decisions on libraries’ collections could be taken with greater confidence and a clearer awareness of national provision. CURL was seeking to establish which CCM approaches could be expected to: · offer the most attractive benefits for costs incurred; · be applicable to a wide range of subjects / areas; · and be viable in the longer term. In lat 2002 CURL accepted a proposal from an existing project team to undertake this work.

  6. Infochemical use by predatory mites of the cassava green mite in a multitrophic context

    NARCIS (Netherlands)

    Gnanvossou, D.

    2002-01-01

    This thesis describes research on multitrophic interactions in a system consisting of (1) cassava plants ( Manihot esculenta ), (2) three herbivorous mites, i.e. the cassava green mite Mononychellus tanajoa, the red spider mite Oligonychus gossypii and the two-spotted spider mite Tetranychus urticae

  7. Human Demodex Mite: The Versatile Mite of Dermatological Importance

    Directory of Open Access Journals (Sweden)

    Parvaiz Anwar Rather

    2014-01-01

    Full Text Available Demodex mite is an obligate human ecto-parasite found in or near the pilo-sebaceous units. Demodex folliculorum and Demodex brevis are two species typically found on humans. Demodex infestation usually remains asymptomatic and may have a pathogenic role only when present in high densities and also because of immune imbalance. All cutaneous diseases caused by Demodex mites are clubbed under the term demodicosis or demodicidosis, which can be an etiological factor of or resemble a variety of dermatoses. Therefore, a high index of clinical suspicion about the etiological role of Demodex in various dermatoses can help in early diagnosis and appropriate, timely, and cost effective management.

  8. Human demodex mite: the versatile mite of dermatological importance.

    Science.gov (United States)

    Rather, Parvaiz Anwar; Hassan, Iffat

    2014-01-01

    Demodex mite is an obligate human ecto-parasite found in or near the pilo-sebaceous units. Demodex folliculorum and Demodex brevis are two species typically found on humans. Demodex infestation usually remains asymptomatic and may have a pathogenic role only when present in high densities and also because of immune imbalance. All cutaneous diseases caused by Demodex mites are clubbed under the term demodicosis or demodicidosis, which can be an etiological factor of or resemble a variety of dermatoses. Therefore, a high index of clinical suspicion about the etiological role of Demodex in various dermatoses can help in early diagnosis and appropriate, timely, and cost effective management.

  9. PARALLEL AUXILIARY SPACE AMG FOR H(curl) PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    Tzanio V. Kolev; Panayot S. Vassilevski

    2009-01-01

    In this paper we review a number of auxiliary space based preconditioners for the second order definite and semi-definite Maxwell problems discretized with the lowest order Nedelec finite elements. We discuss the parallel implementation of the most promising of these methods, the ones derived from the recent Hiptmair-Xu (HX) auxiliary space decomposition [Hiptmair and Xu, SIAM J. Numer. Anal., 45 (2007), pp. 2483-2509]. An extensive set of numerical experiments demonstrate the scalability of our implementation on large-scale H(curl) problems.

  10. The role of volatiles in aggregation and host-seeking of the haematophagous poultry red mite Dermanyssus gallinae (Acari: Dermanyssidae)

    NARCIS (Netherlands)

    Koenraadt, C.J.M.; Dicke, M.

    2010-01-01

    Infestations with ectoparasitic poultry red mites (Dermanyssus gallinae) pose an increasing threat to poultry health and welfare. Because of resistance to acaricides and higher scrutiny of poultry products, alternative and environmentally safe management strategies are warranted. Therefore, we inves

  11. Why do Varroa mites prefer nurse bees?

    Science.gov (United States)

    Xie, Xianbing; Huang, Zachary Y.; Zeng, Zhijiang

    2016-01-01

    The Varroa mite, Varroa destructor, is an acarine ecto-parasite on Apis mellifera. It is the worst pest of Apis mellifera, yet its reproductive biology on the host is not well understood. In particular, the significance of the phoretic stage, when mites feed on adult bees for a few days, is not clear. In addition, it is not clear whether the preference of mites for nurses observed in the laboratory also happens inside real colonies. We show that Varroa mites prefer nurses over both newly emerged bees and forgers in a colony setting. We then determined the mechanism behind this preference. We show that this preference maximizes Varroa fitness, although due to the fact that each mite must find a second host (a pupa) to reproduce, the fitness benefit to the mites is not immediate but delayed. Our results suggest that the Varroa mite is a highly adapted parasite for honey bees. PMID:27302644

  12. Suppressors of RNA silencing encoded by tomato leaf curl betasatellites

    Indian Academy of Sciences (India)

    Richa Shukla; Sunita Dalal; V G Malathi

    2013-03-01

    Virus encoded RNA-silencing suppressors (RSSs) are the key components evolved by the viruses to counter RNA-silencing defense of plants. Whitefly-transmitted begomoviruses infecting tomato crop code for five different proteins, ORF AC4, ORF AC2 and ORF AV2 in DNA-A component, ORF BV1 in DNA-B and ORF C1 in satellite DNA which are predicted to function as silencing suppressors. In the present study suppressor function of ORF C1 of three betasatellites Tomato leaf curl Bangalore betasatellite ToLCBB-[IN:Hess:08], Cotton leaf curl Multan betasatellite CLCuMB–[IN:Sri:02] and Luffa leaf distortion betasatellite LuLDB-[IN:Lu:04] were examined. Agroinfiltration of GFP-silenced Nicotiana tabaccum cv. Xanthi with the cells expressing C1 protein resulted in reversal of silenced GFP expression. GFP-siRNA level was more than 50-fold lower compared to silenced plants in plants infiltrated with C1 gene from ToLCBB. However, in the case of 35S-C1 CLCuMB and 35S-C1 LuLDB construct, although GFP was expressed, siRNA level was not reduced, indicating that the step at which C1 interfere in RNA-silencing pathway is different.

  13. Suppressors of RNA silencing encoded by tomato leaf curl betasatellites.

    Science.gov (United States)

    Shukla, Richa; Dalal, Sunita; Malathi, V G

    2013-03-01

    Virus encoded RNA-silencing suppressors (RSSs) are the key components evolved by the viruses to counter RNA-silencing defense of plants. Whitefly-transmitted begomoviruses infecting tomato crop code for five different proteins, ORF AC4, ORF AC2 and ORF AV2 in DNA-A component, ORF BV1 in DNA-B and ORF beta C1 in satellite DNA beta which are predicted to function as silencing suppressors. In the present study suppressor function of ORF beta C1 of three betasatellites Tomato leaf curl Bangalore betasatellite ToLCBB-[IN:Hess:08], Cotton leaf curl Multan betasatellite CLCuMB-[IN:Sri:02] and Luffa leaf distortion betasatellite LuLDB-[IN:Lu:04] were examined. Agroinfiltration of GFP-silenced Nicotiana tabaccum cv. Xanthi with the cells expressing betaC1 protein resulted in reversal of silenced GFP expression. GFP-siRNA level was more than 50-fold lower compared to silenced plants in plants infiltrated with betaC1 gene from ToLCBB. However, in the case of 35S-beta C1 CLCuMB and 35S- beta C1 LuLDB construct, although GFP was expressed, siRNA level was not reduced, indicating that the step at which beta C1 interfere in RNA-silencing pathway is different.

  14. Edge curling that has plagued scrolls for millenniums

    Science.gov (United States)

    Chou, Ming-Han; Shen, Wei-Chao; Wang, Yi-Ping; Hung, Sun-Hsin; Hong, Tzay-Ming; Department of Registration and Conservation, National Palace Museum Collaboration; Department of Physics, National Tsing Hua University Team

    2014-03-01

    Qi-Wa refers to the up curl on the lengths of handscrolls and hanging scrolls, which has troubled Chinese artisans and emperors for as long as the art of painting and calligraphy exists. This warp is unwelcome not only for aesthetic reasons, but its potential damage to the fiber and ink. Although it is generally treated as a part of the cockling and curling due to moisture, consistency of paste, and defects from the mounting procedures, we demonstrate that the spontaneous extrinsic curvature incurred from the storage is in fact more essential to understanding and curing Qi-Wa. In contrast to the former factors whose effects are less predictable, the plastic deformation and strain distribution on a membrane are a well-defined mechanical problem. We study this phenomenon by experiments, theoretical models, and Molecular Dynamics Simulation, and obtain consistent scaling relations for the Qi-Wa height. This knowledge enables us to propose modifications on the traditional mounting techniques, that are tested on real mounted paper to be effective at mitigating Qi-Wa. By experimenting on polymer-based films, we demonstrate possible relevance of our study to the modern development of flexible electronic paper.

  15. Curling Edges: A Problem that Has Plagued Scrolls for Millennia

    Science.gov (United States)

    Chou, Ming-Han; Shen, Wei-Chao; Wang, Yi-Ping; Hung, Sun-Hsin; Hong, Tzay-Ming

    2014-01-01

    Qi-Wa refers to the up curl on the lengths of hand scrolls and hanging scrolls, which has troubled Chinese artisans and emperors for as long as the art of painting and calligraphy has existed. This warp is unwelcome not only for aesthetic reasons, but its potential damage to the fiber and ink. Although it is generally treated as a part of the cockling and curling due to moisture, consistency of paste, and defects from the mounting procedures, we demonstrate that the spontaneous extrinsic curvature incurred from the storage is in fact more essential to understanding and curing Qi-Wa. In contrast to the former factors whose effects are less predictable, the plastic deformation and strain distribution on a membrane are a well-defined mechanical problem. We study this phenomenon by experiments, theoretical models, and molecular dynamics simulation, and obtain consistent scaling relations for the Qi-Wa height. This knowledge enables us to propose modifications on the traditional mounting techniques that are tested on real mounted paper to be effective at mitigating Qi-Wa. By experimenting on polymer-based films, we demonstrate the possible relevance of our study to the modern development of flexible electronic paper.

  16. House Dust Mite Respiratory Allergy

    DEFF Research Database (Denmark)

    Calderón, Moisés A; Kleine-Tebbe, Jörg; Linneberg, Allan

    2015-01-01

    Although house dust mite (HDM) allergy is a major cause of respiratory allergic disease, specific diagnosis and effective treatment both present unresolved challenges. Guidelines for the treatment of allergic rhinitis and asthma are well supported in the literature, but specific evidence on the e...

  17. Honey Bees: Sweetness and Mites

    Science.gov (United States)

    Honey bee colony losses have been in the news lately and the potential reasons for these losses have taken up much space in the news media. In order to clarify what role mites play in the current loss (2006-2007) of bee colonies, called Colony Collapse Disorder, a better understanding of what a mit...

  18. House dust mites, our intimate associates.

    Science.gov (United States)

    Nadchatram, M

    2005-06-01

    House dust mites have lived in human contact from time immemorial. Human dander or dead skin constitutes the major organic component of the house dust ecosystem. Because the mites feed on dander, dust mites and human association will continue to co-exist as part of our environment. Efficient house-keeping practice is the best form of control to reduce infestation. However, special precautions are important when individuals are susceptible or sensitive to dust mites. House dust mites are responsible for causing asthma, rhinitis and contact dermatitis. The respiratory allergies are caused by the inhalation of dead or live mites, their faecal matter or other byproducts. Immune factors are of paramount importance in the development of dust related or mite induced respiratory diseases. House dust mites were found in some 1,000 samples of dust taken from approximately 330 dwellings in Peninsular Malaysia and Singapore. Mattresses, carpets, corners of a bedroom, and floor beneath the bed are favourable dust mite habitats. The incriminating species based on studies here and elsewhere, as well as many other species of dust mites of unknown etiological importance are widely distributed in Malaysian homes. Density of dust mites in Malaysia and Singapore is greater than in temperate countries. Prevention and control measures with reference to subjects sensitive to dust mite allergies, including chemical control described in studies conducted in Europe and America are discussed. However, a cost free and most practical way to remove mites, their faecal matter and other products is to resort to sunning the bedding and carpets to kill the living mites, and then beaten and brushed to remove the dust and other components.

  19. Chromosomal rearrangements between tomato and Solanum chilense hamper mapping and breeding of the TYLCV resistance gene Ty-1

    NARCIS (Netherlands)

    Verlaan, M.G.; Szinay, D.; Hutton, S.F.; Jong, de J.H.; Kormelink, R.J.M.; Visser, R.G.F.; Scott, J.W.; Bai, Y.

    2011-01-01

    Tomato yellow leaf curl disease, a devastating disease of Solanum lycopersicum (tomato), is caused by a complex of begomoviruses generally referred to as Tomato yellow leaf curl virus (TYLCV). Almost all breeding for TYLCV resistance has been based on the introgression of the Ty-1 resistance locus

  20. Population Growth of Varroa destructor (Acari: Varroidae) in Colonies of Russian and Unselected Honey Bee (Hymenoptera: Apidae) Stocks as Related to Numbers of Foragers With Mites.

    Science.gov (United States)

    DeGrandi-Hoffman, Gloria; Ahumada, Fabiana; Danka, Robert; Chambers, Mona; DeJong, Emily Watkins; Hidalgo, Geoff

    2017-06-01

    Varroa (Varroa destructor Anderson and Trueman) is an external parasite of honey bees (Apis mellifera L.) and a leading cause of colony losses worldwide. Varroa populations can be controlled with miticides, but mite-resistant stocks such as the Russian honey bee (RHB) also are available. Russian honey bee and other mite-resistant stocks limit Varroa population growth by affecting factors that contribute to mite reproduction. However, mite population growth is not entirely due to reproduction. Numbers of foragers with mites (FWM) entering and leaving hives also affect the growth of mite populations. If FWM significantly contribute to Varroa population growth, mite numbers in RHB colonies might not differ from unselected lines (USL). Foragers with mites were monitored at the entrances of RHB and USL hives from August to November, 2015, at two apiary sites. At site 1, RHB colonies had fewer FWM than USL and smaller phoretic mite populations. Russian honey bee also had fewer infested brood cells and lower percentages with Varroa offspring than USL. At site 2, FWM did not differ between RHB and USL, and phoretic mite populations were not significantly different. At both sites, there were sharp increases in phoretic mite populations from September to November that corresponded with increasing numbers of FWM. Under conditions where FWM populations are similar between RHB and USL, attributes that contribute to mite resistance in RHB may not keep Varroa population levels below that of USL. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

  1. Flat acoustic lens by acoustic grating with curled slits

    KAUST Repository

    Peng, Pai

    2014-10-01

    We design a flat sub-wavelength lens that can focus acoustic wave. We analytically study the transmission through an acoustic grating with curled slits, which can serve as a material with tunable impedance and refractive index for acoustic waves. The effective parameters rely on the geometry of the slits and are independent of frequency. A flat acoustic focusing lens by such acoustic grating with gradient effective refractive index is designed. The focusing effect is clearly observed in simulations and well predicted by the theory. We demonstrate that despite the large impedance mismatch between the acoustic lens and the matrix, the intensity at the focal point is still high due to Fabry-Perot resonance.

  2. Study of Demodex mites: Challenges and Solutions.

    Science.gov (United States)

    Lacey, N; Russell-Hallinan, A; Powell, F C

    2016-05-01

    Demodex mites are the largest and most complex organisms of the skin microflora. How they interact with the innate and adaptive immune systems is unknown. Their potential to have a pathogenic role in the causation of human skin disorders causes continued speculation. With growing interest in the microflora of human skin and its relevance to cutaneous health, the role of Demodex mites needs to be better understood. The main challenges facing scientists investigating the role of these organisms and possible solutions are reviewed under the following headings: (1) Determining the mite population in skin, (2) Transporting, extracting and imaging live mites, (3) Maintaining mites viable ex vivo and (4) Establishing methods to determine the immune response to Demodex mites and their internal contents.

  3. Transcript mapping of Cotton leaf curl Burewala virus and its cognate betasatellite, Cotton leaf curl Multan betasatellite

    Directory of Open Access Journals (Sweden)

    Akbar Fazal

    2012-10-01

    Full Text Available Abstract Background Whitefly-transmitted geminiviruses (family Geminiviridae, genus Begomovirus are major limiting factors for the production of numerous dicotyledonous crops throughout the warmer regions of the world. In the Old World a small number of begomoviruses have genomes consisting of two components whereas the majority have single-component genomes. Most of the monopartite begomoviruses associate with satellite DNA molecules, the most important of which are the betasatellites. Cotton leaf curl disease (CLCuD is one of the major problems for cotton production on the Indian sub-continent. Across Pakistan, CLCuD is currently associated with a single begomovirus (Cotton leaf curl Burewala virus [CLCuBuV] and the cotton-specific betasatellite Cotton leaf curl Multan betasatellite (CLCuMuB, both of which have recombinant origins. Surprisingly, CLCuBuV lacks C2, one of the genes present in all previously characterized begomoviruses. Virus-specific transcripts have only been mapped for few begomoviruses, including one monopartite begomovirus that does not associate with betasatellites. Similarly, the transcripts of only two betasatellites have been mapped so far. The study described has investigated whether the recombination/mutation events involved in the evolution of CLCuBuV and its associated CLCuMuB have affected their transcription strategies. Results The major transcripts of CLCuBuV and its associated betasatellite (CLCuMuB from infected Nicotiana benthamiana plants have been determined. Two complementary-sense transcripts of ~1.7 and ~0.7 kb were identified for CLCuBuV. The ~1.7 kb transcript appears similar in position and size to that of several begomoviruses and likely directs the translation of C1 and C4 proteins. Both complementary-sense transcripts can potentially direct the translation of C2 and C3 proteins. A single virion-sense transcript of ~1 kb, suitable for translation of the V1 and V2 genes was identified. A predominant

  4. Recombinant house dust mite allergens

    OpenAIRE

    2013-01-01

    House dust mites (HDM) are a globally important source of allergen responsible for the sensitization of more than 50% of allergic patients. Specific immunotherapy with HDM extracts is effective but allergen extracts cannot be fully standardized and severe side-effects can occur during the protracted course of treatment. The introduction of molecular biological techniques into allergy research allowed the indentification of more than 20 groups of HDM allergens. Recombinant HDM allergens can be...

  5. Ecology of Postlarval Stages of Chigger Mites.

    Science.gov (United States)

    1985-12-05

    reason is the large variance inherent in soil arthropod data (Hughes 1962, Nef 1962). Owing to the low numbers of astigmatid mites collected in this study...from positive and negative chigger sites showed that one species of astigmatid mite , "Acaridae sp. II", had significantly higher populations at...AD-A162 524 ECOLOGY OF POSTLRRVAL STAGES OF CHIGGER MITES (U) GEORGIA UNIV ATHENS DEPT OF ENTOMOLOGY CROSSLEY ET AL 85 DEC 85 N88814486-C-0547 UCASFED

  6. Infochemical use by predatory mites of the cassava green mite in a multitrophic context

    NARCIS (Netherlands)

    Gnanvossou, D.

    2002-01-01

    This thesis describes research on multitrophic interactions in a system consisting of (1) cassava plants ( Manihot esculenta ), (2) three herbivorous mites, i.e. the cassava green mite Mononychellus tanajoa, the red spider mite Oligonychus

  7. House dust mite control measures for asthma

    DEFF Research Database (Denmark)

    Gøtzsche, Peter C.; Johansen, Helle Krogh

    2008-01-01

    antigens in the homes of people with mite-sensitive asthma. SEARCH STRATEGY: PubMed and The Cochrane Library (last searches Nov 2007), reference lists. SELECTION CRITERIA: Randomised trials of mite control measures vs placebo or no treatment in people with asthma known to be sensitive to house dust mites.......07), or in medication usage (standardised mean difference -0.06, 95% CI -0.18 to 0.07). AUTHORS' CONCLUSIONS: Chemical and physical methods aimed at reducing exposure to house dust mite allergens cannot be recommended. It is doubtful whether further studies, similar to the ones in our review, are worthwhile. If other...

  8. Wind Stress, METOP ASCAT, 0.25 degrees, Global, Near Real Time, Curl

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes near real time wind stress data in zonal, meridional, modulus, and wind stress curl sets. This data begins with wind velocity...

  9. A Scott bench with ergonomic thorax stabilisation pad improves body posture during preacher arm curl exercise.

    Science.gov (United States)

    Biscarini, Andrea; Benvenuti, Paolo; Busti, Daniele; Zanuso, Silvano

    2016-05-01

    We assessed whether the use of an ergonomic thorax stabilisation pad, during the preacher arm curl exercise, could significantly reduce the excessive shoulder protraction and thoracic kyphosis induced by the standard flat pad built into the existing preacher arm curl equipment. A 3D motion capture system and inclinometers were used to measure shoulder protraction and thoracic kyphosis in 15 subjects performing preacher arm curl with a plate-loaded machine provided with the standard flat pad. The same measures were repeated after replacing the flat pad with a new ergonomic pad, specifically designed to accommodate the thorax profile and improve body posture. Pad replacement significantly (p thorax stabilisation pad for the preacher arm curl exercise. The new ergonomic pad improves the poor posture conditions induced by the standard flat pad and may potentially allow a more effective training, prevent musculoskeletal discomfort, improve the breathing function and reduce the risk of injury.

  10. Wind Stress, QuikSCAT SeaWinds, 0.25 degrees, Global, Science Quality, Curl

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes science quality wind stress data in zonal, meridional, modulus, and wind stress curl sets. This data begins with wind velocity...

  11. Wind Stress, METOP ASCAT, 0.25 degrees, Global, Near Real Time, Curl

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes near real time wind stress data in zonal, meridional, modulus, and wind stress curl sets. This data begins with wind velocity...

  12. Wind Stress, QuikSCAT SeaWinds, 0.25 degrees, Global, Science Quality, Curl

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — NOAA CoastWatch distributes science quality wind stress data in zonal, meridional, modulus, and wind stress curl sets. This data begins with wind velocity...

  13. Senna leaf curl virus: a novel begomovirus identified in Senna occidentalis.

    Science.gov (United States)

    Kumar, Jitesh; Alok, Anshu; Kumar, Jitendra; Tuli, Rakesh

    2016-09-01

    Begomoviruses are whitefly-transmitted, single-stranded DNA viruses that infect a variety of cultivated (crop) and non-cultivated (weed) plants. The present study identified a novel begomovirus and satellites (alpha- and betasatellite) in Senna occidentalis (syn. Cassia occidentalis) showing leaf curl symptoms. The begomovirus shared a maximum sequence identity of 88.6 % with french bean leaf curl virus (JQ866297), whereas the alphasatellite and the betasatellite shared identities of 98 % and 90 % with ageratum yellow vein India alphasatellite (LK054802) and papaya leaf curl betasatellite (HM143906), respectively. No other begomovirus or satellites were detected in the suspected plants. We propose to name the virus "senna leaf curl virus" (SenLCuV).

  14. Molecular Identification and Sequence Analysis of Tobacco Leaf Curl Begomovirus from Jember, East Java, Indonesia

    Directory of Open Access Journals (Sweden)

    SRI HENDRASTUTI HIDAYAT

    2008-03-01

    Full Text Available Begomovirus had been proved as the causal agent of leaf curl disease in tobacco in Indonesia, or commonly in Indonesia called as penyakit krupuk tembakau. Association of Begomovirus with the disease was further confirmed by sequence analysis. Amplification of the virus was conducted following whitefly (Bemisia tabaci Genn. transmission. Fragment of DNA 1.6 kb was amplified by polymerase chain reaction (PCR located within the replication initiator protein gene and coat protein gene (top region. Conserved sequence of stem loop region was found, included nonanucleotide sequence TAATATTAC present in all geminiviruses. Begomovirus associated with leaf curl disease in tobacco showed the closest relationship with Ageratum yellow vein virus - Zimbabwe, a strain of Tobacco leaf curl virus from Southern Africa. It was also known that Begomovirus associated with leaf curl disease in tobacco from Jember, East Java was different from other Indonesian Begomoviruses reported earlier.

  15. Scales of North Atlantic wind stress curl determined from the comprehensive ocean-atmosphere data set

    Science.gov (United States)

    Ehret, Laura L.; O'Brien, James J.

    1989-01-01

    Nineteen years of wind data over the North Atlantic are used to calculate a field of wind stress curl. An empirical orthogonal function (EOF) analysis is performed on this field, resulting in spatial patterns of wind stress curl and associated time series. A Monte Carlo technique is used to establish the statistical significance of each spatial pattern, and the associated time series are spectrally analyzed. The first four statistically significant EOF modes represent more than 50 percent of the curl variance, and the spatial patterns of curl associated with these modes exhibit the major elements of North Atlantic climatology. Most of the time series spectral variance is contained in annual and semiannual frequencies. The features observed include the individual annual variation of the subtropical high and the subpolar low, the annual oscillation of intensity between pressure centers, the influence of localized strong SST gradients and associated cyclogenesis regions, and the constant nature of the trades.

  16. Detection and Host Range Study of Virus Associated with Pepper Yellow Leaf Curl Disease

    Directory of Open Access Journals (Sweden)

    SRI SULANDARI

    2006-03-01

    Full Text Available High incidence of Pepper yellow leaf curl virus (PepYLCV was observed in Indonesia since early 2000. Disease incidence in Yogyakarta, Central and West Java reached 100% on Capsicum frutescens, but only 10-35% on C. annuum. As an exception, the disease incidence on C. annuum cv. TM 999 was in the range of 70-100%. The causal agent of the disease, PepYLCV, was detected by polymerase chain reaction. Viral specific DNA fragment of the size ~1600 bp and ~550 bp was amplified from infected plants using two pairs of geminivirus universal primers pAL1v1978/pAL1c715, and pAv494/pAc1048, respectively. The PepYLCV has an intermediate host range including plants belonging to the family of Solanaceae, Leguminosae, and Compositae. The species belonging to the families of Cucurbitaceae, Malvaceae, Chenopodiaceae, and Amaranthaceae were resistant to the virus. Physalis floridana, is very prospective as a propagation host for the geminivirus infecting pepper. Nicotiana spp., cucumber, watermelon, cotton, and Sida sp. could be used as a differential host. Besides, Capsicum frutescens cv. Cakra, tomato, N. benthamiana, N. glutinosa, and Ageratum conyzoides could be used as indicator plants for the geminivirus infecting pepper.

  17. Domatia reduce larval cannibalism in predatory mites

    NARCIS (Netherlands)

    Ferreira, J.A.M.; Eshuis, B.; Janssen, A.; Sabelis, M.W.

    2008-01-01

    1. Acarodomatia are small structures on the underside of leaves of many plant species, which are mainly inhabited by carnivorous and fungivorous mites. 2. Domatia are thought to protect these mites against adverse environmental conditions and against predation. They are considered as an indirect pla

  18. Behavioural responses to potential dispersal cues in two economically important species of cereal-feeding eriophyid mites.

    Science.gov (United States)

    Kiedrowicz, Agnieszka; Kuczyński, Lechosław; Lewandowski, Mariusz; Proctor, Heather; Skoracka, Anna

    2017-06-20

    Passively dispersing organisms should optimise the time and direction of dispersal by employing behaviours that increase their probability of being successfully transported by dispersal agents. We rigorously tested whether two agriculturally important passively-dispersing eriophyoid species, wheat curl mite (WCM) and cereal rust mite (CRM), display behaviours indicating their readiness to depart from current host plants in the presence of potential dispersal cues: wind, an insect vector and presence of a fresh plant. Contrary to our expectations, we found that both species decreased their general activity in the presence of wind. When exposed to wind, WCM (but not CRM) significantly increased behaviour that has previously been considered to facilitate dispersal (in this case, standing vertically). Our study provides the first sound test of the function of what have been interpreted as dispersal-related behaviours of eriophyid mites. The low proportion of WCM exhibiting dispersal behaviour suggests there may be predisposed dispersers and residents in the population. Moreover, we found that WCM was generally more active than CRM, which is likely a contributing factor to its high invasive potential.

  19. Curling dynamics of naturally curved ribbons from high to low Reynolds numbers

    Science.gov (United States)

    Albarran Arriagada, Octavio; Massiera, Gladys; Abkarian, Manouk

    2012-11-01

    Curling deformation of thin elastic sheets appears in numerous structures in nature, such as membranes of red blood cells, epithelial tissues or green algae colonies to cite just a few examples. However, despite its ubiquity, the dynamics of curling propagation in a naturally curved material remains still poorly investigated. Here, we present a coupled experimental and theoretical study of the dynamical curling deformation of naturally curved ribbons. Using thermoplastic and metallic ribbons molded on cylinders of different radii, we tune separately the natural curvature and the geometry to study curling dynamics in air, water and in viscous oils, thus spanning a wide range of Reynolds numbers. Our theoretical and experimental approaches separate the role of elasticity, gravity and hydrodynamic dissipation from inertia and emphasize the fundamental differences between the curling of a naturally curved ribbon and a rod described by the classical Elastica. Our work shows evidence for the propagation of a single instability front, selected by a local buckling condition. We show that depending on gravity, and both the Reynolds and the Cauchy numbers, the curling speed and shape are modified by the large scale drag and the local lubrication forces. This work was supported by the French Ministry of Research, the CNRS Physics-Chemistry-Biology Interdisciplinary Pro- gram, the University Montpellier 2 Interdisciplinary Program and the Region Languedoc-Roussillon.

  20. Analytical solutions of the electrostatically actuated curled beam problem

    KAUST Repository

    Younis, Mohammad I.

    2014-07-24

    This works presents analytical expressions of the electrostatically actuated initially deformed cantilever beam problem. The formulation is based on the continuous Euler-Bernoulli beam model combined with a single-mode Galerkin approximation. We derive simple analytical expressions for two commonly observed deformed beams configurations: the curled and tilted configurations. The derived analytical formulas are validated by comparing their results to experimental data and numerical results of a multi-mode reduced order model. The derived expressions do not involve any complicated integrals or complex terms and can be conveniently used by designers for quick, yet accurate, estimations. The formulas are found to yield accurate results for most commonly encountered microbeams of initial tip deflections of few microns. For largely deformed beams, we found that these formulas yield less accurate results due to the limitations of the single-mode approximation. In such cases, multi-mode reduced order models are shown to yield accurate results. © 2014 Springer-Verlag Berlin Heidelberg.

  1. Novel Synthetic Promoters from the Cestrum Yellow Leaf Curling Virus.

    Science.gov (United States)

    Sahoo, Dipak Kumar; Sarkar, Shayan; Maiti, Indu B; Dey, Nrisingha

    2016-01-01

    Constitutive promoters direct gene expression uniformly in most tissues and cells at all stages of plant growth and development; they confer steady levels of transgene expression in plant cells and hence their demand is high in plant biology. The gene silencing due to promoter homology can be avoided by either using diverse promoters isolated from different plant and viral genomes or by designing synthetic promoters. The aim of this chapter was to describe the basic protocols needed to develop and analyze novel, synthetic, nearly constitutive promoters from Cestrum yellow leaf curling virus (CmYLCV) through promoter/leader deletion and activating cis-sequence analysis. We also describe the methods to evaluate the strength of the promoters efficiently in various transient expression systems like agroinfiltration assay, gene-gun method, and assay in tobacco protoplasts. Besides, the detailed methods for developing transgenic plants (tobacco and Arabidopsis) for evaluation of the promoter using the GUS reporter gene are also described. The detailed procedure for electrophoretic mobility shift assay (EMSA) coupled with super-shift EMSA analysis are also described for showing the binding of tobacco transcription factor, TGA1a to cis-elements in the CmYLCV distal promoter region.

  2. Evaluating Weeds as Hosts of Tomato yellow leaf curl virus.

    Science.gov (United States)

    Smith, Hugh A; Seijo, Teresa E; Vallad, Gary E; Peres, Natalia A; Druffel, Keri L

    2015-08-01

    Bemisia tabaci (Gennadius) biotype B transmits Tomato yellow leaf curl virus (TYLCV), which affects tomato production globally. Prompt destruction of virus reservoirs is a key component of virus management. Identification of weed hosts of TYLCV will be useful for reducing such reservoirs. The status of weeds as alternate hosts of TYLCV in Florida remains unclear. In greenhouse studies, B. tabaci adults from a colony reared on TYLCV-infected tomato were established in cages containing one of four weeds common to horticultural fields in central and south Florida. Cages containing tomato and cotton were also infested with viruliferous whiteflies as a positive control and negative control, respectively. Whitefly adults and plant tissue were tested periodically over 10 wk for the presence of TYLCV using PCR. After 10 wk, virus-susceptible tomato plants were placed in each cage to determine if whiteflies descended from the original adults were still infective. Results indicate that Bidens alba, Emilia fosbergii, and Raphanus raphanistrum are not hosts of TYLCV, and that Amaranthus retroflexus is a host. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. TaqMan real-time PCR for detection and quantitation of squash leaf curl virus in cucurbits.

    Science.gov (United States)

    Kuan, Cheng-Ping; Huang, Hung-Chang; Chang, Chia-Che; Lu, Yi-Lin

    2012-02-01

    A real-time PCR assay based on the TaqMan chemistry was developed for reliable detection and quantitation of the squash leaf curl virus (SLCV) in melon and squash plants. This method was highly specific to SLCV and it was about one thousand times more sensitive than the conventional PCR method. The protocol of the real-time PCR established in this study enabled detection of as little as 10(2) copies of SLCV DNA with CP gene as the target. This TaqMan real-time PCR assay for detection and quantitation of SLCV would be a useful tool for application in quarantine and certification of SLCV in cucurbits as well as in the research of disease resistance and epidemiology.

  4. The role of mites in insect-fungus associations

    Science.gov (United States)

    R. W. Hofstetter; J. C. Moser

    2014-01-01

    The interactions among insects, mites, and fungi are diverse and complex but poorly understood in most cases. Associations among insects, mites, and fungi span an almost incomprehensible array of ecological interactions and evolutionary histories. Insects and mites often share habitats and resources and thus interact within communities. Many mites and insects rely on...

  5. The economic importance of acaricides in the control of phytophagous mites and an update on recent acaricide mode of action research.

    Science.gov (United States)

    Van Leeuwen, Thomas; Tirry, Luc; Yamamoto, Atsushi; Nauen, Ralf; Dermauw, Wannes

    2015-06-01

    Acaricides are one of the cornerstones of an efficient control program for phytophagous mites. An analysis of the global acaricide market reveals that spider mites such as Tetranychus urticae, Panonychus citri and Panonychus ulmi are by far the most economically important species, representing more than 80% of the market. Other relevant mite groups are false spider mites (mainly Brevipalpus), rust and gall mites and tarsonemid mites. Acaricides are most frequently used in vegetables and fruits (74% of the market), including grape vines and citrus. However, their use is increasing in major crops where spider mites are becoming more important, such as soybean, cotton and corn. As revealed by a detailed case study of the Japanese market, major shifts in acaricide use are partially driven by resistance development and the commercial availability of compounds with novel mode of action. The importance of the latter cannot be underestimated, although some compounds are successfully used for more than 30 years. A review of recent developments in mode of action research is presented, as such knowledge is important for devising resistance management programs. This includes spirocyclic keto-enols as inhibitors of acetyl-CoA carboxylase, the carbazate bifenazate as a mitochondrial complex III inhibitor, a novel class of complex II inhibitors, and the mite growth inhibitors hexythiazox, clofentezine and etoxazole that interact with chitin synthase I.

  6. Differential gene expression associated with honey bee grooming behavior in response to varroa mites

    Science.gov (United States)

    Honey bee (Apis mellifera) grooming behavior is an important mechanism of resistance against the parasitic mite Varroa destructor. This research was conducted to study associations between grooming behavior and the expression of selected immune, neural, detoxification, developmental and health-relat...

  7. Cotton leaf curl disease - an emerging threat to cotton production worldwide.

    Science.gov (United States)

    Sattar, M Naeem; Kvarnheden, Anders; Saeed, Muhammad; Briddon, Rob W

    2013-04-01

    Cotton leaf curl disease (CLCuD) is a serious disease of cotton which has characteristic symptoms, the most unusual of which is the formation of leaf-like enations on the undersides of leaves. The disease is caused by whitefly-transmitted geminiviruses (family Geminiviridae, genus Begomovirus) in association with specific, symptom-modulating satellites (betasatellites) and an evolutionarily distinct group of satellite-like molecules known as alphasatellites. CLCuD occurs across Africa as well as in Pakistan and north-western India. Over the past 25 years, Pakistan and India have experienced two epidemics of the disease, the most recent of which involved a virus and satellite that are resistance breaking. Loss of this conventional host-plant resistance, which saved the cotton growers from ruin in the late 1990s, leaves farmers with only relatively poor host plant tolerance to counter the extensive losses the disease causes. There has always been the fear that CLCuD could spread from the relatively limited geographical range it encompasses at present to other cotton-growing areas of the world where, although the disease is not present, the environmental conditions are suitable for its establishment and the whitefly vector occurs. Unfortunately recent events have shown this fear to be well founded, with CLCuD making its first appearance in China. Here, we outline recent advances made in understanding the molecular biology of the components of the disease complex, their interactions with host plants, as well as efforts being made to control CLCuD.

  8. Haematophagus Mites in Poultry Farms of Iran

    Science.gov (United States)

    Rahbari, S; Nabian, S; Ronaghi, H

    2009-01-01

    Background: Blood sucking mites are important avian ectoparasites which being found on bird species worldwide. Their presence are problematic for the producers either through potential direct effects on weight gain, egg production, sperm production in roosters or as nuisance pests on worker handle hens and eggs. The aim of this study was pointing out of the status of haematophagus mites. Methods: Eight caged layer and four breeder flocks were visited, monitoring for the presence of chicken mites performed by removing and examining debris from poultry house, infested nesting material collected into zip lock plastic bags and at least 20 birds were also randomly selected to examine the presence of chicken mites. Mites obtained from each population were mounted in Hoyer’s medium on microscope slides and identified. All eight caged layer and four breeder flocks were inspected, which were infested with chicken blood feeding mites. Results: Massive infestations of Dermanyssus gallinae were common with huge numbers of parasites on birds, cages and the conveyor belts for egg. Only one farm from Mazandaran Province was infested to Ornithonyssus bursa. Conclusion: Dermanyssus gallinae was the most prevalent blood feeder mite in the breeder and caged layer flocks in Iran, while O. bursa was reported as a first record, which found only in a breeder flock in Mazanderan Province. It seems that its presence is limited into the area which affected by both warm and humid environmental conditions. PMID:22808378

  9. Haematophagus Mites in Poultry Farms of Iran

    Directory of Open Access Journals (Sweden)

    S Rahbari

    2009-12-01

    Full Text Available Background: Blood sucking mites are important avian ectoparasites which being found on bird species worldwide. Their presence are problematic for the producers either through potential direct effects on weight gain, egg produc­tion, sperm production in roosters or as nuisance pests on worker handle hens and eggs. The aim of this study was pointing out of the status of haematophagus mites.Methods: Eight caged layer and four breeder flocks were visited, monitoring for the presence of chicken mites per­formed by removing and examining debris from poultry house, infested nesting material collected into zip lock plas­tic bags and at least 20 birds were also randomly selected to examine the presence of chicken mites. Mites obtained from each population were mounted in Hoyer,s medium on microscope slides and identified. All eight caged layer and four breeder flocks were inspected, which were infested with chicken blood feeding mites.Results: Massive infestations of Dermanyssus gallinae were common with huge numbers of parasites on birds, cages and the conveyor belts for egg. Only one farm from Mazandaran Province was infested to Ornithonyssus bursa.Conclusion: Dermanyssus gallinae was the most prevalent blood feeder mite in the breeder and caged layer flocks in Iran, while O. bursa was reported as a first record, which found only in a breeder flock in Mazanderan Province. It seems that its presence is limited into the area which affected by both warm and humid environmental conditions.

  10. Comparison of thread-cutting behaviour in three specialist predatory mites to cope with complex webs of Tetranychus spider mites

    NARCIS (Netherlands)

    Shimoda, T.; Kishimoto, H.; Takabayashi, J.; Amano, H.; Dicke, M.

    2009-01-01

    Anti-predator defenses provided by complex webs of Tetranychus mites can severely impede the performance of generalist predatory mites, whereas this may not be true for specialist predatory mites. Although some specialist predatory mites have developed morphological protection to reduce the adverse

  11. Allergy to house dust mites and asthma.

    Science.gov (United States)

    Milián, Evelyn; Díaz, Ana María

    2004-03-01

    House dust mites have been shown to be important sources of indoor allergens associated with asthma and other allergic conditions. Asthma is a chronic respiratory disease that affects millions of people worldwide, and numerous scientific studies have shown that the prevalence of asthma is increasing. The most common dust mite species around the world include Dermatophagoides pteronyssinus (Dp), Dermatophagoides farinae (Df), Euroglyphus maynei (Em) and Blomia tropicalis (Bt). Over the past three decades, many important allergens from these species have been identified and characterized at the molecular level. The biological function of several house dust mite allergens has been elucidated, with many of them showing enzymatic activity. However, Bt allergens remain the least studied, even though this mite is very common in tropical and subtropical regions of the world, including Puerto Rico. Therefore, it is very important to include Bt in diagnostic and therapeutic strategies for house dust mite induced allergy and asthma, particularly in areas where Bt exposure and sensitization is high. Recombinant DNA technology, as well as other molecular biology and immunological techniques, have played a fundamental role in advances towards a better understanding of the biology of house dust mites and their role in allergic diseases. This kind of study also contributes to the understanding of the complex immunologic mechanisms involved in allergic reactions. The development of effective diagnostic and therapeutic approaches depends on the continuity of research of house dust mite allergens. The objectives of this review are to describe the most important aspects of house dust mite allergy and to acquaint the scientific community with the latest findings pertaining to house dust mite allergens, particularly those derived from Bt.

  12. EFFECT OF THE SHOULDER POSITION ON THE BICEPS BRACHII EMG IN DIFFERENT DUMBBELL CURLS

    Directory of Open Access Journals (Sweden)

    Taian M.M. Vieira

    2009-03-01

    Full Text Available Incline Dumbbell Curl (IDC and Dumbbell Preacher Curl (DPC are two variations of the standard Dumbbell Biceps Curl (DBC, generally applied to optimize biceps brachii contribution for elbow flexion by fixing shoulder at a specific angle. The aim of this study is to identify changes in the neuromuscular activity of biceps brachii long head for IDC, DPC and DBC exercises, by taking into account the changes in load moment arm and muscle length elicited by each dumbbell curl protocol. A single cycle (concentric-eccentric of DBC, IDC and DPC, was applied to 22 subjects using a submaximal load of 40% estimated from an isometric MVC test. The neuromuscular activity of biceps brachii long head was compared by further partitioning each contraction into three phases, according to individual elbow joint range of motion. Although all protocols elicited a considerable level of activation of the biceps brachii muscle (at least 50% of maximum RMS, the contribution of this muscle for elbow flexion/extension varied among exercises. The submaximal elbow flexion (concentric elicited neuro muscular activity up to 95% of the maximum RMS value during the final phase of IDC and DBC and 80% for DPC at the beginning of the movement. All exercises showed significant less muscle activity for the elbow extension (eccentric. The Incline Dumbbell Curl and the classical Dumbbell Biceps Curl resulted in similar patterns of biceps brachii activation for the whole range of motion, whereas Dumbbell Preacher Curl elicited high muscle activation only for a short range of elbow joint angle

  13. BIO-EFFICACY OF NEWER INSECTICIDES AGAINST TOMATO LEAF CURL VIRUS DISEASE AND ITS VECTOR WHITEFLY (BEMISIA TABACI) IN TOMATO

    National Research Council Canada - National Science Library

    Govindappa, M.R; Bhemanna, M; Arunkumar Hosmani; V.N. Ghante

    2013-01-01

    .... Present investigations on Invitro efficacy of new insecticide molecules on whitefly mortality and leaf curl virus transmission revealed that adult mortality varies with the length of incubation...

  14. Light and scanning electron microscopic investigations on MiteStop-treated poultry red mites.

    Science.gov (United States)

    Locher, Nina; Klimpel, Sven; Abdel-Ghaffar, Fathy; Al Rasheid, Khaled A S; Mehlhorn, Heinz

    2010-07-01

    Recent studies of the neem seed product MiteStop showed that it has a good acaricidal effect against all developmental stages of the poultry red mite, Dermanyssus gallinae. In vitro tests proved an efficacy at direct contact, as well as by fumigant toxicity. Light and scanning electron microscopic (SEM) investigations showed no clear, morphologically visible signs of an effect caused by fumigant toxicity. Direct contact with the neem product, however, seemed to be of great impact. Chicken mites turned dark brown or even black after being treated with the neem product. SEM analysis showed damages along the body surface of the mites.

  15. Giardia cyst wall protein 1 is a lectin that binds to curled fibrils of the GalNAc homopolymer.

    Science.gov (United States)

    Chatterjee, Aparajita; Carpentieri, Andrea; Ratner, Daniel M; Bullitt, Esther; Costello, Catherine E; Robbins, Phillips W; Samuelson, John

    2010-08-19

    The infectious and diagnostic stage of Giardia lamblia (also known as G. intestinalis or G. duodenalis) is the cyst. The Giardia cyst wall contains fibrils of a unique beta-1,3-linked N-acetylgalactosamine (GalNAc) homopolymer and at least three cyst wall proteins (CWPs) composed of Leu-rich repeats (CWP(LRR)) and a C-terminal conserved Cys-rich region (CWP(CRR)). Our goals were to dissect the structure of the cyst wall and determine how it is disrupted during excystation. The intact Giardia cyst wall is thin (approximately 400 nm), easily fractured by sonication, and impermeable to small molecules. Curled fibrils of the GalNAc homopolymer are restricted to a narrow plane and are coated with linear arrays of oval-shaped protein complex. In contrast, cyst walls of Giardia treated with hot alkali to deproteinate fibrils of the GalNAc homopolymer are thick (approximately 1.2 microm), resistant to sonication, and permeable. The deproteinated GalNAc homopolymer, which forms a loose lattice of curled fibrils, is bound by native CWP1 and CWP2, as well as by maltose-binding protein (MBP)-fusions containing the full-length CWP1 or CWP1(LRR). In contrast, neither MBP alone nor MBP fused to CWP1(CRR) bind to the GalNAc homopolymer. Recombinant CWP1 binds to the GalNAc homopolymer within secretory vesicles of Giardia encysting in vitro. Fibrils of the GalNAc homopolymer are exposed during excystation or by treatment of heat-killed cysts with chymotrypsin, while deproteinated fibrils of the GalNAc homopolymer are degraded by extracts of Giardia cysts but not trophozoites. These results show the Leu-rich repeat domain of CWP1 is a lectin that binds to curled fibrils of the GalNAc homopolymer. During excystation, host and Giardia proteases appear to degrade bound CWPs, exposing fibrils of the GalNAc homopolymer that are digested by a stage-specific glycohydrolase.

  16. Giardia cyst wall protein 1 is a lectin that binds to curled fibrils of the GalNAc homopolymer.

    Directory of Open Access Journals (Sweden)

    Aparajita Chatterjee

    2010-08-01

    Full Text Available The infectious and diagnostic stage of Giardia lamblia (also known as G. intestinalis or G. duodenalis is the cyst. The Giardia cyst wall contains fibrils of a unique beta-1,3-linked N-acetylgalactosamine (GalNAc homopolymer and at least three cyst wall proteins (CWPs composed of Leu-rich repeats (CWP(LRR and a C-terminal conserved Cys-rich region (CWP(CRR. Our goals were to dissect the structure of the cyst wall and determine how it is disrupted during excystation. The intact Giardia cyst wall is thin (approximately 400 nm, easily fractured by sonication, and impermeable to small molecules. Curled fibrils of the GalNAc homopolymer are restricted to a narrow plane and are coated with linear arrays of oval-shaped protein complex. In contrast, cyst walls of Giardia treated with hot alkali to deproteinate fibrils of the GalNAc homopolymer are thick (approximately 1.2 microm, resistant to sonication, and permeable. The deproteinated GalNAc homopolymer, which forms a loose lattice of curled fibrils, is bound by native CWP1 and CWP2, as well as by maltose-binding protein (MBP-fusions containing the full-length CWP1 or CWP1(LRR. In contrast, neither MBP alone nor MBP fused to CWP1(CRR bind to the GalNAc homopolymer. Recombinant CWP1 binds to the GalNAc homopolymer within secretory vesicles of Giardia encysting in vitro. Fibrils of the GalNAc homopolymer are exposed during excystation or by treatment of heat-killed cysts with chymotrypsin, while deproteinated fibrils of the GalNAc homopolymer are degraded by extracts of Giardia cysts but not trophozoites. These results show the Leu-rich repeat domain of CWP1 is a lectin that binds to curled fibrils of the GalNAc homopolymer. During excystation, host and Giardia proteases appear to degrade bound CWPs, exposing fibrils of the GalNAc homopolymer that are digested by a stage-specific glycohydrolase.

  17. Varroa destructor mite in Africanized honeybee colonies Apis mellifera L. under royal jelly or honey production

    Directory of Open Access Journals (Sweden)

    Pedro da Rosa Santos

    2015-08-01

    Full Text Available This study evaluated the level of invasion of Varroa mite into worker brood cells, the infestation rate on adult worker honeybees, total and effective reproduction rates of the mite in Africanized honeybee colonies under royal jelly or honey production. Invasion and infestation rates were not statistically different between honeybee colonies producing honey or royal jelly and the averages for these parameters were 5.79 and 8.54%, respectively. Colonies producing honey presented a higher (p < 0.05 total and effective reproduction of Varroa than colonies producing royal jelly. There was a negative correlation between levels of invasion and infestation with minimum external temperature, relative humidity and rainfall. The variables month and season influenced the development of the mite, but rates were low and within the range normally found in Brazil for Africanized honeybee colonies, which confirm the greater resistance of these honeybees to Varroa destructor than European honeybees.

  18. Reliability of Arm Curl and Chair Stand tests for assessing muscular endurance in older people

    Directory of Open Access Journals (Sweden)

    Boneth M

    2012-05-01

    Full Text Available Objective: to assess the test-retest reliability and level of agreement between measures of the 30 second (30-s Arm Curl and 30-s Chair Stand test in a sample of older adults from Bucaramanga. Materials and methods: a study of evaluation of diagnostic technology was done. Both tests were administered by the same evaluator to 111 adults older than 59 year-old (70,4 ± 7,3, on two occasions, with an interval of time between measures of 4 to 8 days. In the analysis, test-retest reliability was determined using the Intraclass Correlation Coefficient ICC= 2,1 with their confidence interval 95% (CI 95% respective. The agreement level was established by the Bland and Altman method. Results: the test-retest reproducibility of the 30-s Arm Curl test was very good ICC= 0,88 and to the Chair Stand test was good ICC= 0,78. The agreement was very good for both tests of muscle endurance. The CI 95% were between -3,8 and 3,2 stands to 30-s Chair Stand test and between -3,1 and 2,8 curls to 30-s Arm Curl test. Conclusion: the 30-s Arm Curl and 30-s Chair Stand test have good reliability and agreement to assess muscle endurance in older adults functionally independent.

  19. Phylogenetic analysis of Melon chlorotic leaf curl virus from Guatemala: Another emergent species in the Squash leaf curl virus clade

    KAUST Repository

    Brown, J.K.

    2011-06-01

    The genome of a new bipartite begomovirus Melon chlorotic leaf curl virus from Guatemala (MCLCuV-GT) was cloned and the genome sequence was determined. The virus causes distinct symptoms on melons that were not previously observed in melon crops in Guatemala or elsewhere. Phylogenetic analysis of MCLCuV-GT and begomoviruses infecting cucurbits and other host plant species indicated that its closest relative was MCLCuV from Costa Rica (MCLCuV-CR). The DNA-A components of two isolates shared 88.8% nucleotide identity, making them strains of the same species. Further, both MCLCuV-GT and MCLCuV-CR grouped with other Western Hemisphere cucurbit-infecting species in the SLCV-clade making them the most southerly cucurbit-infecting members of the clade to date. Although the common region of the cognate components of MCLCuV-GT and MCLCuV-CR, shared similar to 96.3% nucleotide identity. While DNA-A and DNA-B components of MCLCuV-GT were less than 86% nucleotide identity with the respective DNAA and DNA-B common regions of MCLCuV-CR. The late viral genes of the two strains shared the least nt identity (<88%) while their early genes shared the highest nt identity (>90%). The collective evidence suggests that these two strains of MCLCuV are evolutionarily divergent owing in part to recombination, but also due to the accumulation of a substantial number of mutations. In addition they are differentially host-adapted, as has been documented for other cucurbit-infecting, bean-adapted, species in the SLCV clade. (C) 2011 Elsevier B.V. All rights reserved.

  20. Astigmatid mites (Acari: Sarcoptiformes) of forensic interest.

    Science.gov (United States)

    Oconnor, Barry M

    2009-10-01

    This paper reviews the occurrence of mites of the infraorder Astigmata in situations involving the legal system, particularly in the area of medicocriminal entomology. Species in the families Acaridae, Lardoglyphidae and Histiostomatidae are encountered in stored food products and in vertebrate carrion, including human remains. Some of these species are incidentals, whereas others are obligate necrophages. Phoretic associations between these mites and insects allows for rapid dispersal and colonization of such patchy resources.

  1. The role of mites in insect-fungus associations.

    Science.gov (United States)

    Hofstetter, R W; Moser, J C

    2014-01-01

    The interactions among insects, mites, and fungi are diverse and complex but poorly understood in most cases. Associations among insects, mites, and fungi span an almost incomprehensible array of ecological interactions and evolutionary histories. Insects and mites often share habitats and resources and thus interact within communities. Many mites and insects rely on fungi for nutrients, and fungi benefit from them with regard to spore dispersal, habitat provision, or nutrient resources. Mites have important impacts on community dynamics, ecosystem processes, and biodiversity within many insect-fungus systems. Given that mites are understudied but highly abundant, they likely have bigger, more important, and more widespread impacts on communities than previously recognized. We describe mutualistic and antagonistic effects of mites on insect-fungus associations, explore the processes that underpin ecological and evolutionary patterns of these multipartite communities, review well-researched examples of the effects of mites on insect-fungus associations, and discuss approaches for studying mites within insect-fungus communities.

  2. Scent of a mite: origin and chemical characterization of the lemon-like flavor of mite-ripened cheeses.

    Science.gov (United States)

    Brückner, Adrian; Heethoff, Michael

    2016-07-01

    Cheese infested with cheese mites is usually treated as unpalatable. Nevertheless, some traditional cheese manufactories in Germany and France intentionally use mites for fermentation of special varieties (i.e. Milbenkäse and Mimolette). While their production includes different mite species, both are characterized by a "lemon-like" flavor. However, the chemical nature and origin of this flavor-component is unknown. The cheese mites possess a pair of opisthosomal glands producing blends of hydrocarbons, terpenes and aromatics. Here, we describe the chemical profiles of the astigmatid mite species Tyrolichus casei (Milbenkäse) and Acarus siro (Mimolette). Although the chemical profiles differ in several aspects, both mite species produce neral (a volatile flavor component of lemon oil), which was absent from the headspace of both cheeses without mites. We conclude that the lemon-like flavor of mite cheese is not a consequence of fermentation of the cheese itself but a component from secretions of the cheese mites.

  3. Mitochondrial genome evolution and tRNA truncation in Acariformes mites: new evidence from eriophyoid mites.

    Science.gov (United States)

    Xue, Xiao-Feng; Guo, Jing-Feng; Dong, Yan; Hong, Xiao-Yue; Shao, Renfu

    2016-01-06

    The subclass Acari (mites and ticks) comprises two super-orders: Acariformes and Parasitiformes. Most species of the Parasitiformes known retained the ancestral pattern of mitochondrial (mt) gene arrangement of arthropods, and their mt tRNAs have the typical cloverleaf structure. All of the species of the Acariformes known, however, have rearranged mt genomes and truncated mt tRNAs. We sequenced the mt genomes of two species of Eriophyoidea: Phyllocoptes taishanensis and Epitrimerus sabinae. The mt genomes of P. taishanensis and E. sabinae are 13,475 bp and 13,531 bp, respectively, are circular and contain the 37 genes typical of animals; most mt tRNAs are highly truncated in both mites. On the other hand, these two eriophyoid mites have the least rearranged mt genomes seen in the Acariformes. Comparison between eriophyoid mites and other Aacariformes mites showed that: 1) the most recent common ancestor of Acariformes mites retained the ancestral pattern of mt gene arrangement of arthropods with slight modifications; 2) truncation of tRNAs for cysteine, phenylalanine and histidine occurred once in the most recent common ancestor of Acariformes mites whereas truncation of other tRNAs occurred multiple times; and 3) the placement of eriophyoid mites in the order Trombidiformes needs to be reviewed.

  4. Scabies mite peritrophins are potential targets of human host innate immunity.

    Directory of Open Access Journals (Sweden)

    Angela Mika

    2011-09-01

    Full Text Available BACKGROUND: Pruritic scabies lesions caused by Sarcoptes scabiei burrowing in the stratum corneum of human skin facilitate opportunistic bacterial infections. Emerging resistance to current therapeutics emphasizes the need to identify novel targets for protective intervention. We have characterized several protein families located in the mite gut as crucial factors for host-parasite interactions. Among these multiple proteins inhibit human complement, presumably to avoid complement-mediated damage of gut epithelial cells. Peritrophins are major components of the peritrophic matrix often found in the gut of arthropods. We hypothesized that a peritrophin, if abundant in the scabies mite gut, could be an activator of complement. METHODOLOGY/PRINCIPAL FINDINGS: A novel full length scabies mite peritrophin (SsPTP1 was identified in a cDNA library from scabies mites. The amino acid sequence revealed four putative chitin binding domains (CBD. Recombinant expression of one CBD of the highly repetitive SsPTP1 sequence as TSP-hexaHis-fusion protein resulted in soluble protein, which demonstrated chitin binding activity in affinity chromatography assays. Antibodies against a recombinant SsPTP1 fragment were used to immunohistochemically localize native SsPTP1 in the mite gut and in fecal pellets within the upper epidermis, co-localizing with serum components such as host IgG and complement. Enzymatic deglycosylation confirmed strong N- and O-glycosylation of the native peritrophin. Serum incubation followed by immunoblotting with a monoclonal antibody against mannan binding lectin (MBL, the recognition molecule of the lectin pathway of human complement activation, indicated that MBL may specifically bind to glycosylated SsPTP1. CONCLUSIONS/SIGNIFICANCE: This study adds a new aspect to the accumulating evidence that complement plays a major role in scabies mite biology. It identifies a novel peritrophin localized in the mite gut as a potential target of the

  5. Chinese squash leaf curl virus: a new whitefly-transmitted geminivirus

    Institute of Scientific and Technical Information of China (English)

    洪益国; 王小凤; 田波; 蔡健和

    1995-01-01

    Coat protein (CP) gene of the Chinese squash !eaf curl virus (SqLCV-C) was amplified through PC’R, cloned and completely sequenced. Based on the comparisons at the levels of both CP gene nucleotide and CP -deduced amino acid sequences with other geminiviruses, SqLCV-C is confirmed to be distinct from the American squash leaf curl virus (SqLCV-E). It is a new geminivirus transmitted by whitefly Bemisia tabaci, which infects dicotyledonous plants and is more closely related to the Indian cassava mosaic virus (ICMV).

  6. Chinese tomato yelIow Ieaf curl virus- a new species of geminivirus.

    Science.gov (United States)

    Liu, Y; Cai, J; Li, D; Qin, B; Tian, B

    1998-08-01

    Chine tomato yellow leaf curl virus (TYLCV-CHI) and other geminiviruses were analysed with 20 monoclonaI antibodies. It was shown that TYLCV-CHI is serclogicaIly close to Chinese tabacco Ieaf curl virus (TbLCV-CHI). The fragment of TYLCV-CHI DNA including the common region (CR), N-terminal of coat protein gene and AV1 gene was amplified by PCR and cloned, and its DNA sequence was determined. These raults showed that TYLCV-CHI is different from other known geminiviruses in the world, and is a new whitefly-transmitted gerninivirus.

  7. Resistance to Acarapis woodi by honey bees (Hymenoptera: Apidae): divergent selection and evaluation of selection progress.

    Science.gov (United States)

    Nasr, M E; Otis, G W; Scott-Dupree, C D

    2001-04-01

    Two generations of honey bees, Apis mellifera L., selected for resistance to tracheal mites, Acarapis woodi (Rennie), were produced from a foundation stock. The mite resistant lines had significantly low mite abundances and prevalences in each selected generation. The high mite-resistant lines of the first selected generation showed resistance equal to that of bees that had undergone natural selection from tracheal mite infestations for 3 yr in New York. Additionally, the high mite-resistant lines of the second selected generation and Buckfast bees had significantly lower mite abundances and prevalences than honey bees from control colonies which had never been exposed to tracheal mite infestation in Ontario. These results corroborate studies that have shown that honey bees possess genetic components for tracheal mite resistance that can be readily enhanced in a breeding program. The two methods used for evaluating relative resistance of honey bees to tracheal mites, a short-term bioassay and evaluation in field colonies, were positively correlated (rs = 0.64, P < 0.001).

  8. Development and application of triple antibody sandwich enzyme-linked immunosorbent assays for begomovirus detection using monoclonal antibodies against Tomato yellow leaf curl Thailand virus.

    Science.gov (United States)

    Seepiban, Channarong; Charoenvilaisiri, Saengsoon; Warin, Nuchnard; Bhunchoth, Anjana; Phironrit, Namthip; Phuangrat, Bencharong; Chatchawankanphanich, Orawan; Attathom, Supat; Gajanandana, Oraprapai

    2017-05-30

    Tomato yellow leaf curl Thailand virus, TYLCTHV, is a begomovirus that causes severe losses of tomato crops in Thailand as well as several countries in Southeast and East Asia. The development of monoclonal antibodies (MAbs) and serological methods for detecting TYLCTHV is essential for epidemiological studies and screening for virus-resistant cultivars. The recombinant coat protein (CP) of TYLCTHV was expressed in Escherichia coli and used to generate MAbs against TYLCTHV through hybridoma technology. The MAbs were characterized and optimized to develop triple antibody sandwich enzyme-linked immunosorbent assays (TAS-ELISAs) for begomovirus detection. The efficiency of TAS-ELISAs for begomovirus detection was evaluated with tomato, pepper, eggplant, okra and cucurbit plants collected from several provinces in Thailand. Molecular identification of begomoviruses in these samples was also performed through PCR and DNA sequence analysis of the CP gene. Two MAbs (M1 and D2) were generated and used to develop TAS-ELISAs for begomovirus detection. The results of begomovirus detection in 147 field samples indicated that MAb M1 reacted with 2 begomovirus species, TYLCTHV and Tobacco leaf curl Yunnan virus (TbLCYnV), whereas MAb D2 reacted with 4 begomovirus species, TYLCTHV, TbLCYnV, Tomato leaf curl New Delhi virus (ToLCNDV) and Squash leaf curl China virus (SLCCNV). Phylogenetic analyses of CP amino acid sequences from these begomoviruses revealed that the CP sequences of begomoviruses recognized by the narrow-spectrum MAb M1 were highly conserved, sharing 93% identity with each other but only 72-81% identity with MAb M1-negative begomoviruses. The CP sequences of begomoviruses recognized by the broad-spectrum MAb D2 demonstrated a wider range of amino acid sequence identity, sharing 78-96% identity with each other and 72-91% identity with those that were not detected by MAb D2. TAS-ELISAs using the narrow-specificity MAb M1 proved highly efficient for the detection of

  9. Haematophagus Mites in Poultry Farms of Iran

    Directory of Open Access Journals (Sweden)

    S Rahbari

    2009-12-01

    Full Text Available Background: Blood sucking mites are important avian ectoparasites which being found on bird species worldwide. Their presence are problematic for the producers either through potential direct effects on weight gain, egg produc­tion, sperm production in roosters or as nuisance pests on worker handle hens and eggs. The aim of this study was pointing out of the status of haematophagus mites."nMethods: Eight caged layer and four breeder flocks were visited, monitoring for the presence of chicken mites per­formed by removing and examining debris from poultry house, infested nesting material collected into zip lock plas­tic bags and at least 20 birds were also randomly selected to examine the presence of chicken mites. Mites obtained from each population were mounted in Hoyer,s medium on microscope slides and identified. All eight caged layer and four breeder flocks were inspected, which were infested with chicken blood feeding mites."nResults: Massive infestations of Dermanyssus gallinae were common with huge numbers of parasites on birds, cages and the conveyor belts for egg. Only one farm from Mazandaran Province was infested to Ornithonyssus bursa."nConclusion: Dermanyssus gallinae was the most prevalent blood feeder mite in the breeder and caged layer flocks in Iran, while O. bursa was reported as a first record, which found only in a breeder flock in Mazanderan Province. It seems that its presence is limited into the area which affected by both warm and humid environmental conditions.  Keywords: Dermanyssus gallinae, Ornithonyssus bursa, Poultry, Iran

  10. Mite Pests in Plant Crops – Current Issues, Inovative Approaches and Possibilities for Controlling Them (2

    Directory of Open Access Journals (Sweden)

    Radmila Petanović

    2010-01-01

    Full Text Available Part one discusses some principal mite pests in agroecosystems and urban horticulturein European countries, Serbia and its neighbouring countries focusing primarily on issueswith regard to plant production, novel methods and approaches in applied acaralogy. Parttwo displays some major properties of acaricides inhibiting respiration, growth and developmentand other synthetic substances with acaricide action on the market in the last decadeof the 20th century and the first decade of the 21st century. Also some products of naturalorigin (azadirachtin, oils, micoacaricides are said to be gaining in importance. Issues withregard to the fact that mites can readily develop resistance to acardicides are discussed anda survey on the results of biochemical, physiological and genetical causes of resistance areanalyzed. Some basic principles of biological control of phytophagous mites and modernadvances and approaches are discussed as well as current knowledge on host plant resistanceto mites. Eventually, the possibility of using a combination of selective acaricides andbiological control agents is discussed but also the inclusion of other modes of control (agriculturalpractices and physical measures expected to contribute to an integrated managementof pest populations.

  11. Influence of Varroa Mite (Varroa destructor Management Practices on Insecticide Sensitivity in the Honey Bee (Apis mellifera

    Directory of Open Access Journals (Sweden)

    Frank D. Rinkevich

    2017-01-01

    Full Text Available Since Varroa mites may cause devastating losses of honey bees through direct feeding, transmitting diseases, and increasing pathogen susceptibility, chemical and mechanical practices commonly are used to reduce mite infestation. While miticide applications are typically the most consistent and efficacious Varroa mite management method, miticide-induced insecticide synergism in honey bees, and the evolution of resistance in Varroa mites are reasonable concerns. We treated colonies with the miticide amitraz (Apivar®, used IPM practices, or left some colonies untreated, and then measured the effect of different levels of mite infestations on the sensitivity of bees to phenothrin, amitraz, and clothianidin. Sensitivity to all insecticides varied throughout the year among and within treatment groups. Clothianidin sensitivity decreased with increasing mite levels, but no such correlation was seen with phenothrin or amitraz. These results show that insecticide sensitivity is dynamic throughout the 5 months test. In-hive amitraz treatment according to the labeled use did not synergize sensitivity to the pesticides tested and this should alleviate concern over potential synergistic effects. Since IPM practices were largely ineffective at reducing Varroa mite infestation, reliance on chemical methods of Varroa mite management is likely to continue. However, miticides must be used judiciously so the long term effectiveness of these compounds can be maximized. These data demonstrate the complex and dynamic variables that contribute to honey bee colony health. The results underscore the importance of controlling for as many of these variables as possible in order to accurately determine the effects of each of these factors as they act alone or in concert with others.

  12. Influence of Varroa Mite (Varroa destructor) Management Practices on Insecticide Sensitivity in the Honey Bee (Apis mellifera)

    Science.gov (United States)

    Rinkevich, Frank D.; Danka, Robert G.; Healy, Kristen B.

    2017-01-01

    Since Varroa mites may cause devastating losses of honey bees through direct feeding, transmitting diseases, and increasing pathogen susceptibility, chemical and mechanical practices commonly are used to reduce mite infestation. While miticide applications are typically the most consistent and efficacious Varroa mite management method, miticide-induced insecticide synergism in honey bees, and the evolution of resistance in Varroa mites are reasonable concerns. We treated colonies with the miticide amitraz (Apivar®), used IPM practices, or left some colonies untreated, and then measured the effect of different levels of mite infestations on the sensitivity of bees to phenothrin, amitraz, and clothianidin. Sensitivity to all insecticides varied throughout the year among and within treatment groups. Clothianidin sensitivity decreased with increasing mite levels, but no such correlation was seen with phenothrin or amitraz. These results show that insecticide sensitivity is dynamic throughout the 5 months test. In-hive amitraz treatment according to the labeled use did not synergize sensitivity to the pesticides tested and this should alleviate concern over potential synergistic effects. Since IPM practices were largely ineffective at reducing Varroa mite infestation, reliance on chemical methods of Varroa mite management is likely to continue. However, miticides must be used judiciously so the long term effectiveness of these compounds can be maximized. These data demonstrate the complex and dynamic variables that contribute to honey bee colony health. The results underscore the importance of controlling for as many of these variables as possible in order to accurately determine the effects of each of these factors as they act alone or in concert with others. PMID:28085045

  13. Influence of Varroa Mite (Varroa destructor) Management Practices on Insecticide Sensitivity in the Honey Bee (Apis mellifera).

    Science.gov (United States)

    Rinkevich, Frank D; Danka, Robert G; Healy, Kristen B

    2017-01-11

    Since Varroa mites may cause devastating losses of honey bees through direct feeding, transmitting diseases, and increasing pathogen susceptibility, chemical and mechanical practices commonly are used to reduce mite infestation. While miticide applications are typically the most consistent and efficacious Varroa mite management method, miticide-induced insecticide synergism in honey bees, and the evolution of resistance in Varroa mites are reasonable concerns. We treated colonies with the miticide amitraz (Apivar(®)), used IPM practices, or left some colonies untreated, and then measured the effect of different levels of mite infestations on the sensitivity of bees to phenothrin, amitraz, and clothianidin. Sensitivity to all insecticides varied throughout the year among and within treatment groups. Clothianidin sensitivity decreased with increasing mite levels, but no such correlation was seen with phenothrin or amitraz. These results show that insecticide sensitivity is dynamic throughout the 5 months test. In-hive amitraz treatment according to the labeled use did not synergize sensitivity to the pesticides tested and this should alleviate concern over potential synergistic effects. Since IPM practices were largely ineffective at reducing Varroa mite infestation, reliance on chemical methods of Varroa mite management is likely to continue. However, miticides must be used judiciously so the long term effectiveness of these compounds can be maximized. These data demonstrate the complex and dynamic variables that contribute to honey bee colony health. The results underscore the importance of controlling for as many of these variables as possible in order to accurately determine the effects of each of these factors as they act alone or in concert with others.

  14. Development of a cDNA microarray for the measurement of gene expression in the sheep scab mite Psoroptes ovis

    Directory of Open Access Journals (Sweden)

    Burgess Stewart TG

    2012-02-01

    Full Text Available Abstract Background Sheep scab is caused by the ectoparasitic mite Psoroptes ovis which initiates a profound cutaneous inflammatory response, leading to the development of the skin lesions which are characteristic of the disease. Existing control strategies rely upon injectable endectocides and acaricidal dips but concerns over residues, eco-toxicity and the development of acaricide resistance limit the sustainability of this approach. In order to identify alternative means of disease control, a deeper understanding of both the parasite and its interaction with the host are required. Methods Herein we describe the development and utilisation of an annotated P. ovis cDNA microarray containing 3,456 elements for the measurement of gene expression in this economically important ectoparasite. The array consists of 981 P. ovis EST sequences printed in triplicate along with 513 control elements. Array performance was validated through the analysis of gene expression differences between fed and starved P. ovis mites. Results Sequences represented on the array include homologues of major house dust mite allergens and tick salivary proteins, along with factors potentially involved in mite reproduction and xenobiotic metabolism. In order to validate the performance of this unique resource under biological conditions we used the array to analyse gene expression differences between fed and starved P. ovis mites. These analyses identified a number of house dust mite allergen homologues up-regulated in fed mites and P. ovis transcripts involved in stress responses, autophagy and chemosensory perception up-regulated in starved mites. Conclusion The P. ovis cDNA microarray described here has been shown to be both robust and reproducible and will enable future studies to analyse gene expression in this important ectoparasite.

  15. Analysis of resonance frequency and pull-in voltages of curled micro-bimorph cantilevers

    NARCIS (Netherlands)

    Abdulla, S.M.C.; Yagubizade, H.; Krijnen, G.J.M.

    2012-01-01

    A systematic study is presented on the modelling, fabrication and measurements of curled micro-bimorph cantilevers, which are composed of a dielectric beam with a metal electrode layer coated on top. The device, having stress-induced upward curvature in the electrical off-state, functions as a verti

  16. Serological and molecular identification of Tomato yellow leaf curl virus in Khuzestan province of Iran

    Directory of Open Access Journals (Sweden)

    Shahrokh MALEKZADEH

    2011-09-01

    Full Text Available A survey was conducted from 2006 to 2007 to identify the causal agent of leaf curling of tomato in eight major tomato-growing areas of Khuzestan province in southwest of Iran. Tomato leaf samples showing leaf curling, yellowing, and stunting were collected and screened for the presence of Tomato yellow leaf curl virus (TYLCV by TAS-ELISA. Further confi rmation was completed using graft transmission onto healthy tomato plants and PCR. Results confi rmed that TYLCV is a causal agent of tomato yellow leaf curl disease (TYLCD and is widely distributed in all the major tomato growing areas in southwest of Iran. The nucleotide sequences of the coat protein (CP gene of four isolates (Dezfoul, Shoush, Behbahan, and Ramhormoz were determined and deposited in GenBank (EF199814-7. Phylogenetic analysis of the CP gene further showed that all four Iranian isolates have very close relationship and formed a Compact cluster together with previously sequenced Iranian TYLCV isolates.

  17. Molecular characterization and pathogenicity of tomato yellow leaf curl virus in China.

    Science.gov (United States)

    Zhang, Hui; Gong, Huanran; Zhou, Xueping

    2009-10-01

    Several tomato production regions in China were surveyed for tomato yellow leaf curl disease (TYLCD), and 31 tomato leaf samples showing TYLCD-like symptoms were collected. The partial or full-length genomes of these isolates were sequenced and tomato yellow leaf curl virus (TYLCV) was detected in Shanghai, Zhejiang, Jiangsu Shandong and Hebei provinces of China. The TYLCV isolates found in China share high sequence identity ([98%) and have more than 97% sequence identity with TYLCVIL[ IL:Reo] (X15656). Phylogenetic relationship analysis reveals that although with little genetic variability, they can form two groups and all the TYLCV isolates in China belong to the group I. An infectious clone of TYLCV-[CN:SH2] (AM282874) was constructed and agro-inoculated into Nicotiana benthamiana, N. tabacum Samsun, N. glutinosa, Solanum lycopersicum, Petunia hybrida, Cucumis sativus, Gossypium hirsutum, S. melongena, and Capsicum annuum. TYLCV-[CN:SH2] can induce severe leaf curling and stunting symptoms in these plants except C. sativus, G. hirsutum, S. melongena and C. annuum.We verified that TYLCV can trans-replicate tomato yellow leaf curl China virus DNA-b in N. benthamiana and S. lycopersicum and induced more severe symptoms with distortion and yellow vein.

  18. Relationship between Tomato yellow leaf curl viruses and the whitefly vector.

    Science.gov (United States)

    Ssekyewa, Charles; Van Damme, Patrick L J; Hofte, Monica

    2007-01-01

    Tomato Yellow Leaf Curl Virus (TYLCV) and Tomato Leaf Curl Virus (ToLCV) are the currently known begomoviruses in Uganda. The relationship with their whiteflies (Bemisia tabaci) vector and its management were not known in Uganda. A direct relationship was expected between these begomoviruses and whiteflies at Buwama in Mpigi district of Uganda. Farmer practices were expected to have limited efficacy. To investigate this, a completely randomised block design was used for all trials with six treatments replicated three times. Treatments evaluated were farmer whitefly pest management practices. These included both chemical pesticide and non-pesticide applications. Data on whitefly population and tomato yellow leaf curl virus disease incidence was recorded weekly, and analysed using SAS and SPSS statistical programmes for ANOVA, and correlations. Ranked means, coefficients of variation and standard errors were noted. Virus-vector relationship field studies established that virus occurrence varied in space and time, and with management practices, crop development stage, and weather conditions. A negative relationship (R = -0.14, p 0.04) was established between number of plants infected with TYLCV (sensu lato) and percentage marketable tomato yield. Tomato maturity was inversely propotional to whitefly infestation (R = -0.5, p 0.0001). Uprooting and application of dimethoate was most effective of the six treatments. Tomato leaf curl virus diseases and whitefly management options were established in Uganda.

  19. First Report of Tomato yellow leaf curl virus in Tomato in the Netherlands

    NARCIS (Netherlands)

    Botermans, M.; Verhoeven, J.Th.J.; Jansen, C.C.C.; Roenhorst, J.W.; Stijger, C.C.M.M.; Pham, K.T.K.

    2009-01-01

    Tomato yellow leaf curl virus (TYLCV) is an economically important virus with tomato (Solanum lycopersicum L.) as its main host. The virus is widely distributed in subtropical areas and is transmitted by the tobacco whitefly (Bemisia tabaci) in a persistent manner. TYLCV has a quarantine status

  20. Spatial and temporal diversity of begomoviral complexes in papayas with leaf curl disease.

    Science.gov (United States)

    Singh-Pant, P; Pant, P; Mukherjee, S K; Mazumdar-Leighton, S

    2012-07-01

    Old World, monopartite begomoviruses associated with satellite DNA β were observed in papaya showing symptoms of leaf curl disease sampled randomly over five years from within a radius of 250 km in north-central India. Three groups of DNA A sequences were evident. One group resembled chili leaf curl virus infecting tomatoes (ChiLCuV). Another group resembled tomato leaf curl New Delhi virus (ToLCuNDV). The third group was novel (tentatively named papaya leaf crumple virus, PaLCrV), with less than 89% identity to known begomovirus sequences in the GenBank database. At least seven DNA A sequences were putative recombinants. The AC4-encoding regions exhibited highest numbers of non-synonymous substitutions. Most DNA β sequences resembled tomato leaf curl virus-associated DNA βs. A few DNA β sequences were similar to that of croton yellow vein mosaic virus-associated DNA β (CroYVMVβ). One DNA β sequence was novel and showed papayas grown in plantations, kitchen gardens and feral patches in the region are vulnerable to disease outbreak. No geographic or temporal patterns were discernable in the distribution of these viruses.

  1. Is the begomovirus, sweet potato leaf curl virus, really seed transmitted in sweetpotato?

    Science.gov (United States)

    Sweetpotato is one of the major root crops in the world and is also widely grown in the southern United States. Sweet potato leaf curl virus (SPLCV) is a begomovirus posing a serious threat to sweetpotato production worldwide and is primarily transmitted by whitefly (Bemisia tabaci) or through veget...

  2. Effects of thermal treatments with a curling iron on hair fiber.

    Science.gov (United States)

    Ruetsch, S B; Kamath, Y K

    2004-01-01

    The effect of curling hair with a curling iron has been investigated. Possibilities of thermal damage with repeated curling according to, and in violation of, the manufacturer's specifications have been studied. The propensity of hair surface to damage depends on the moisture content of the hair, and these experiments have been conducted in both wet and dry conditions, with and without application of tension, and with short or prolonged times. Scanning electron microscopic (SEM) examination revealed that fibers treated under the dry condition (50% RH) show radial and axial cracking along with scale edge fusion. Similar thermal treatment on wet hair resulted in severe damage of the type described above, as well as bubbling and buckling of the cuticle due to the formation and escaping of steam from the fiber. Fibers subjected to repeated curling in the dry condition show slight increases in tensile mechanical properties, characteristic of a crosslinked fiber. Fibers treated with conditioners show an improvement in characteristic life, especially in the case of low-molecular-weight conditioners, such as CETAB, which can penetrate into the hair fiber (shown by TOF-SIMS analysis).

  3. First Report of Tomato yellow leaf curl virus in Tomato in the Netherlands

    NARCIS (Netherlands)

    Botermans, M.; Verhoeven, J.Th.J.; Jansen, C.C.C.; Roenhorst, J.W.; Stijger, C.C.M.M.; Pham, K.T.K.

    2009-01-01

    Tomato yellow leaf curl virus (TYLCV) is an economically important virus with tomato (Solanum lycopersicum L.) as its main host. The virus is widely distributed in subtropical areas and is transmitted by the tobacco whitefly (Bemisia tabaci) in a persistent manner. TYLCV has a quarantine status (IIA

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

    Science.gov (United States)

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

  5. Sweet Potato Leaf Curl Virus: Virus Reservoir in Species of Wild Morning Glory

    Science.gov (United States)

    Recent increases in populations of the Sweetpotato leaf curl virus (SPLCV) vector, the sweetpotato whitefly, Bemisia tabaci (Gennadius), led to a dramatic increase in the disease in sweetpotato (Ipomoea batatas). Knowledge of crop or weed species that occur in sweetpotato growing areas and can serv...

  6. Whitefly transmission of Sweet potato leaf curl virus in sweetpotato germplasm

    Science.gov (United States)

    Sweetpotato, Ipomoea batatas (L.) Lam., is among an extensive number of plant species attacked by Bemisia tabaci (Gennadius). Because this important world food crop is vegetatively propagated, it can conveniently accumulate infections by several viruses. Sweet potato leaf curl virus (SPLCV) (ssDNA...

  7. Wind stress, curl and vertical velocity in the Bay of Bengal during southwest monsoon, 1984

    Digital Repository Service at National Institute of Oceanography (India)

    Babu, M.T.; Heblekar, A.K.; Murty, C.S.

    Wind distribution observed during southwest monsoon of 1984 has used to derive the mean wind stress for the season at every 1 degree square grid and curl over the Bay of Bengal. Two regions of maximum wind stress are present over the Bay of Bengal...

  8. Enzymatic activity in extracts of allergy-causing astigmatid mites.

    Science.gov (United States)

    Morgan, Marjorie S; Arlian, Larry G

    2006-11-01

    Many of the previously characterized allergens of house dust mites are known to be proteases, and this enzymatic activity is thought to contribute to their allergenicity. Other astigmatid mites, including stored-product mites and the ectoparasitic itch mite, Sarcoptes scabiei De Geer, are also known to be allergenic, but little or nothing is known about their enzymatic activities. The purpose of this study was to characterize the enzymatic activities present in extracts of the parasitic itch mite and from eight other species of free-living astigmatid mites. Extracts were prepared from one parasitic mite (S. scabiei), five stored-product mites (Chortoglyphus arcuatus (Troupeau), Lepidoglyphus destructor (Schrank), Blomia tropicalis Bronswijk, Cock, Oshima, Tyrophagus putrescentiae (Schrank), and Acarus siro L.), and three house dust mites [Dermatophagoidesfarinae Hughes, Dermatophagoides pteronyssinus (Troussart), and Euroglyphus maynei (Cooreman) ]. ApiZym strips were used to screen for the presence of 19 individual enzyme activities. Digestion of nine other substrates was evaluated by spectrophotometric or electrophoretic methods. All mite extracts exhibited some form of phosphatase, esterase, aminopeptidase, and glycosidase activity, although their substrate specificities varied considerably. Itch mite extract did not possess detectable serine peptidase activity nor was it able to hydrolyze gelatin or casein, whereas all other mite extracts exhibited these activities. Storage mite extracts possessed enzymes capable of degrading the widest range of substrates, whereas itch mite extract had the most limited proteolytic capacity. Extracts of nine species of allergy-causing astigmatid mites contain wide and diverse repertoires of enzymatic activities. These catalytic activities may be important contributors to the induction and manifestation of inflammatory and immune responses to mites in patients.

  9. Acaricides and predatory mites against the begonia mite, Polyphagotarsonemus latus (Acari: Tarsonemidae), on Hedera helix.

    Science.gov (United States)

    Audenaert, Joachim; Vissers, Marc; Haleydt, Bart; Verhoeven, Ruth; Goossens, Frans; Gobin, Bruno

    2009-01-01

    In recent years, the begonia mite (Polyphagotarsonemus lotus) has become an important threat to different ornamental cultures in warm greenhouses. At present there are no professional plant protection products registered in Belgium for the control of mites of the Tarsonemidae family. In a screening trial, we evaluated the efficacy of a range of different acaricides: abamectin, milbemectin, pyridaben, spirodiclofen. Based on the results of the screening trial several products were selected for a full efficacy trial following EPPO guidelines. The best control results were obtained with two products from the avermectine group: abamectin and milbemectin. As growers currently have to rely solely on the use of natural enemies there is a strong need for practical evaluation of efficacies of the various predatory mite species (Amblyseius swirskii, A. cucumeris, A. andersoni) used in biological mite control. In a series of experiments, we screened the use of different species of predatory mites. The first efficacy trials on heavily infested plants at different rates of dosage and under different circumstances (temperature, dose rate, application technique) were started in May 2008. In these experiments Amblyseius swirskii showed good efficacy. But temperature was the limiting factor: the predatory mite needed a minimal temperature of 18 degrees C to obtain good results. Further research is necessary to search for predatory mites that can be used in winter conditions (lower temperatures, less light).

  10. House dust mites in Brazil - an annotated bibliography

    Directory of Open Access Journals (Sweden)

    Binotti Raquel S

    2001-01-01

    Full Text Available House dust mites have been reported to be the most important allergen in human dwellings. Several articles had already shown the presence of different mite species at homes in Brazil, being Pyroglyphidae, Glycyphagidae and Cheyletidae the most important families found. This paper is an annotated bibliography that will lead to a better knowledge of house dust mite fauna in Brazil.

  11. Does the removal of mite-infested brood facilitate grooming?

    Science.gov (United States)

    The relationship between the removal of mite-infested brood and mite drop was compared using Russian (RHB, n = 9) and Italian (IHB, n = 9) honey bee colonies. A cloake board was used to isolate test brood frame on the top hive body and the metal sheet served as a varroa trap. Inoculum mites were col...

  12. Mites associated with bark beetles and their hyperphoretic ophiostomatoid fungi

    Science.gov (United States)

    Richard W. Hofstetter; John Moser; Stacy Blomquist

    2014-01-01

    The role that mites play in many ecosystems is often overlooked or ignored. Within bark beetle habitats, more than 100 mite species exist and they have important impacts on community dynamics, ecosystem processes, and biodiversity of bark beetle systems. Mites use bark beetles to access and disperse among beetle-infested trees and the associations may range from...

  13. Limiting factors for growth and development of domestic mites

    NARCIS (Netherlands)

    Lynden, A.M.T. van; Kort, H.S.M.; Koren, L.G.H.; Pernot, C.E.E.; Bronswijk, J.E.M.H. van

    1996-01-01

    A quarter to half of European households are at risk of health damage due to mites in their home. House dust mites (family Pyroglyphidae) and storage mites (families Acaridae and Gly-cyphagidae) are present; both groups being specific for different ecosystems: house-dust ecosystem of textiles (house

  14. A Rapid and Efficient Method for Construction of an Infectious Clone of Tomato yellow leaf curl virus

    Directory of Open Access Journals (Sweden)

    Bongjun Bang

    2014-09-01

    Full Text Available Tomato yellow leaf curl virus (TYLCV, a member of the genus Begomovirus, is responsible for one of the most devastating viral diseases in tomato-growing countries and is becoming a serious problem in many subtropical and tropical countries. The climate in Korea is getting warmer and developing subtropical features in response to global warming. These changes are being accompanied by TYLCV, which is now becoming a large problem in the Korean tomato industry. The most effective way to reduce damage caused by TYLCV is to breed resistant varieties of tomatoes. To accomplish this, it is necessary to establish a simple inoculation technique for the efficient evaluation of resistance to TYLCV. Here, we present the rolling circle amplification (RCA method, which employs a bacteriophage using phi-29 DNA polymerase for construction of infectious TYLCV clones. The RCA method is simple, does not require sequence information for cloning, and is less expensive and time consuming than conventional PCR based-methods. Furthermore, RCA-based construction of an infectious clone can be very useful to other emerging and unknown geminiviruses in Korea.

  15. A Rapid and Efficient Method for Construction of an Infectious Clone of Tomato yellow leaf curl virus.

    Science.gov (United States)

    Bang, Bongjun; Lee, Jongyun; Kim, Sunyoung; Park, Jungwook; Nguyen, Thao Thi; Seo, Young-Su

    2014-09-01

    Tomato yellow leaf curl virus (TYLCV), a member of the genus Begomovirus, is responsible for one of the most devastating viral diseases in tomato-growing countries and is becoming a serious problem in many subtropical and tropical countries. The climate in Korea is getting warmer and developing subtropical features in response to global warming. These changes are being accompanied by TYLCV, which is now becoming a large problem in the Korean tomato industry. The most effective way to reduce damage caused by TYLCV is to breed resistant varieties of tomatoes. To accomplish this, it is necessary to establish a simple inoculation technique for the efficient evaluation of resistance to TYLCV. Here, we present the rolling circle amplification (RCA) method, which employs a bacteriophage using phi-29 DNA polymerase for construction of infectious TYLCV clones. The RCA method is simple, does not require sequence information for cloning, and is less expensive and time consuming than conventional PCR based-methods. Furthermore, RCA-based construction of an infectious clone can be very useful to other emerging and unknown geminiviruses in Korea.

  16. Identificação do limiar de lactato e limiar glicêmico em exercícios resistidos Identificación de los límites de lactato y de glicemia en ejercicio continuo Identification of the lactate threshold and the blood glucose threshold in resistance exercise

    Directory of Open Access Journals (Sweden)

    João Carlos de Oliveira

    2006-12-01

    pausa entre las etapas (YSI 2300 S. El comportamiento de glicemia y lactatemia fueron similares en ambos ejercicios estudiados. No se encontraron diferencias significativas (p > 0,05 entre los percentiles de 1RM en los límites lactatémicos y glicémicos observados respectivamente en LP (36,6 ± 1,4% y 32,9 ± 1,5% y SR (31,2 ± 1,2% y 31,2 ± 1,8%. Se observó alta correlación entre los límites glicémico y lactacidémico identificados tanto en LP (r = 0,80; p The purpose of this study was to verify the possibility of identifying the blood glucose threshold (GT as well as to compare and correlate the GT with the lactate threshold (LT during resistance exercises. Twelve healthy male volunteers aged 24.4 ± 1.2 years and adapted to resistance training were submitted to an incremental resistance exercise with graded intensities according to their maximal workload (kg performed for 1 repetition (1RM on both leg press (LP and bench press (BP. The intensities applied for each 1 min stage were of 10%, 20%, 25%, 30%, 35%, 40%, 50%, 60%, 70%, 80% and 90% of 1RM, respectively, or until volitional exhaustion. Blood lactate and glucose measurements were done each 2 min rest between each stage (YSI 2300 S. The blood lactate and glucose responses were similar for both exercises. No differences were verified for the relative intensity (% 1RM at which the inflection point of blood lactate and glucose curves were observed respectively for LP (36.6 ± 1.4% and 32.9 ± 1.5% and BP (31.2 ± 1.2% and 31.2 ± 1.8% (p > 0.05. Additionally, a high correlation was verified between LT and GT identified both on LP (r = 0.80 and SR (r = 0.73 (p < 0,05. It was concluded that it is possible to identify the LT and GT on resistance exercises. However, additional studies should investigate the meaning of these thresholds and their validity for exercise evaluation and training prescription.

  17. Acaricidal effect and histological damage induced by Bacillus thuringiensis protein extracts on the mite Psoroptes cuniculi.

    Science.gov (United States)

    Dunstand-Guzmán, Emmanuel; Peña-Chora, Guadalupe; Hallal-Calleros, Claudia; Pérez-Martínez, Mario; Hernández-Velazquez, Víctor Manuel; Morales-Montor, Jorge; Flores-Pérez, Fernando Iván

    2015-05-24

    The mite Psoroptes cuniculi is a common worldwide ectoparasite and the most frequently found in rabbit farms. It causes significant economic losses on commercial rabbit breeding associated with poor leather quality, reduced conception rates, weight loss, poor growth and death. Several strategies have been proposed for the treatment of mange caused by this mite, ranging from the use of acaricides, entomopathogenic fungi, essential oils and vaccines. However, therapy and control of both human scabies and animal mange are still based mainly on the use of drugs and chemicals such as ivermectin, which involves disadvantages including genotoxic and cytotoxic effects, resistance and environmental damage. Bacillus thuringiensis is a bacterium, innocuous for human being, domestic animals and plants that produces highly biodegradable proteins, and has been used worldwide for biological control. The aim of this work was to find an alternative treatment based on biological control for scabies caused by Psoroptes cuniculi, using protein extracts from strains of Bacillus thuringiensis. P. cuniculi mites were obtained from naturally infected New Zealand rabbits, and different doses of protein from B. thuringiensis were added to the mites. We measured mortality and obtained the median lethal concentration and median lethal times. For histological analysis, the mites were fixed in 10% formalin, processed according to the paraffin embedded tissue technique. Sections were stained with hematoxylin-eosin to observe the general histological structure. We report here for the first time evidence about the in vitro acaricidal effect caused by the strain GP532 of B. thuringiensis on the mite Psoroptes cuniculi, with an LC50 of 1.3 mg/ml and a LT50 of 68 h. Histological alterations caused by B. thuringiensis on this mite, included the presence of dilated intercellular spaces in the basal membrane, membrane detachment of the peritrophic matrix and morphological alterations in columnar cells

  18. [Mites allergy in children from Tula region].

    Science.gov (United States)

    Zlobina, Zh M; Pron'kina, O V; Khlgatian, S V; Berzhets, A I; Berzhets, V M

    2006-01-01

    Characteristics of allergy to mites in children living in Tula region have been revealed. It was shown that mites from Pyroglyphidae (Dermatophagoides pteronyssinus, Dermatophagoides farinae), Cheyletidae and Glycyphagidae (G. destructor, G. domesticus) families play important role in development of atopic allergy in children from this region. Efficacy of plant-origin acaricide "Milbiol" as part of prophylactic measures was evaluated. Its use in children with mild and intermediate asthma led to decrease of number of wheezing episodes, improvement of respiratory function, lessening of clinical signs of allergic rhinitis, decrease or discontinuation of usage of vasoconstrictive preparations.

  19. Comparative biology and pesticide susceptibility of Amblydromella caudiglans and Galendromus occidentalis as spider mite predators in apple orchards.

    Science.gov (United States)

    Schmidt-Jeffris, Rebecca A; Beers, Elizabeth H

    2015-09-01

    The successful integrated mite management program for Washington apples was based on conservation of the mite predator Galendromus occidentalis (Nesbitt). In the 1960s, this mite was assumed to be the only phytoseiid in Washington commercial apple orchards, due to its preference for the most common mite pest of that period, Tetranychus mcdanieli McGregor, as well as its resistance to organophosphate pesticides. A recent survey of phytoseiids in Washington apple found that another phytoseiid, Amblydromella caudiglans (Schuster) has become common. It is a more generalized predator than G. occidentalis (it is not a Tetranychus spp. specialist) and is not known to be organophosphate-resistant. A series of experiments was conducted to compare the life history, prey consumption, and pesticide tolerance of these two species. Galendromus occidentalis developed more quickly than A. caudiglans, but had slightly lower egg survival. Although A. caudiglans attacked more Tetranychus urticae Koch eggs than G. occidentalis, it could not reproduce on this diet. Both predators performed equally well on a diet of T. urticae protonymphs. Unlike G. occidentalis, A. caudiglans experienced significant mortality when exposed to carbaryl, azinphosmethyl, and bifenazate. Both predators experienced significant mortality due to imidacloprid and spinetoram. These results highlight the key differences between these two predators; the shift away from organophosphate use as well as the change in dominant mite pest to Panonychus ulmi (Koch) may be driving factors for the observed increased abundance of A. caudiglans in Washington apple.

  20. Analyzing the influence of curl speed in fatiguing biceps brachii muscles using sEMG signals and multifractal detrended moving average algorithm.

    Science.gov (United States)

    Marri, Kiran; Swaminathan, Ramakrishnan

    2016-08-01

    In this work, an attempt has been made to analyze surface electromyography (sEMG) signals of fatiguing biceps brachii muscles at different curl speeds using multifractal detrended moving average (MFDMA) algorithm. For this purpose, signals are recorded from fifty eight healthy subjects while performing curl exercise at their comfortable speed until fatigue. The signals of first and last curls are considered as nonfatigue and fatigue conditions, respectively. Further, the number of curls performed by each subject and the endurance time is used for computing the normalized curl speed. The signals are grouped into fast, medium and slow using curl speeds. The curl segments are subjected to MFDMA to derive degree of multifractality (DOM), maximum singularity exponent (MXE) and exponent length multifractality index (EMX). The results show that multifractal features are able to differentiate sEMG signals in fatiguing conditions. The multifractality increased with faster curls as compared with slower curl speed by 12%. High statistical significance is observed using EMX and DOM values between curl speed and fatigue conditions. It appears that this method of analyzing sEMG signals with curl speed can be useful in understanding muscle dynamics in varied neuromuscular conditions and sports medicine.

  1. Dust mites in a routine clinical stool sample

    Institute of Scientific and Technical Information of China (English)

    Bushra Zia; Hassaan Bin Aftab; Mohammad Faizan Zahid; Joveria Farooqi; Feroze Uddin; Mohammad Asim Beg

    2014-01-01

    We report a case of dust mite carriage in a 56-year-old gentleman. Dust mites eggs and larvae were found in a stool sample which was taken for a routine clinical examination. He was completely asymptomatic with no history of rash, airway disease or other allergic manifestations associated with dust mites. We noticed that the oval structure of mite eggs resembled helminth eggs and therefore may be misidentified during routine clinical analysis. As the patient was otherwise healthy, it was concluded that no rigorous antiparasitic therapy was necessary to eliminate dust mites from his system.

  2. Biology and interactions of two distinct monopartite begomoviruses and betasatellites associated with radish leaf curl disease in India

    Directory of Open Access Journals (Sweden)

    Singh AK

    2012-02-01

    Full Text Available Abstract Background Emerging whitefly transmitted begomoviruses are major pathogens of vegetable and fibre crops throughout the world, particularly in tropical and sub-tropical regions. Mutation, pseudorecombination and recombination are driving forces for the emergence and evolution of new crop-infecting begomoviruses. Leaf curl disease of field grown radish plants was noticed in Varanasi and Pataudi region of northern India. We have identified and characterized two distinct monopartite begomoviruses and associated beta satellite DNA causing leaf curl disease of radish (Raphanus sativus in India. Results We demonstrate that RaLCD is caused by a complex of two Old World begomoviruses and their associated betasatellites. Radish leaf curl virus-Varanasi is identified as a new recombinant species, Radish leaf curl virus (RaLCV sharing maximum nucleotide identity of 87.7% with Tomato leaf curl Bangladesh virus-[Bangladesh:2] (Accession number AF188481 while the virus causing radish leaf curl disease-Pataudi is an isolate of Croton yellow vein mosaic virus-[India] (CYVMV-IN (Accession number AJ507777 sharing 95.8% nucleotide identity. Further, RDP analysis revealed that the RaLCV has a hybrid genome, a putative recombinant between Euphorbia leaf curl virus and Papaya leaf curl virus. Cloned DNA of either RaLCV or CYVMV induced mild leaf curl symptoms in radish plants. However, when these clones (RaLCV or CYVMV were individually co-inoculated with their associated cloned DNA betasatellite, symptom severity and viral DNA levels were increased in radish plants and induced typical RaLCD symptoms. To further extend these studies, we carried out an investigation of the interaction of these radish-infecting begomoviruses and their associated satellite, with two tomato infecting begomoviruses (Tomato leaf curl Gujarat virus and Tomato leaf curl New Delhi virus. Both of the tomato-infecting begomoviruses showed a contrasting and differential interaction with

  3. The Feeding Rate of Predatory Mites on Life Stages of Bemisia tabaci Mediterranean Species

    Directory of Open Access Journals (Sweden)

    Andrew G. S. Cuthbertson

    2014-07-01

    Full Text Available The sweetpotato whitefly Bemisia tabaci (Gennadius (Hemiptera: Aleyrodidae continues to be a serious threat to crops worldwide. The UK holds Protected Zone status against this pest and, as a result, B. tabaci entering on plant material is subjected to a policy of eradication. There has recently been a shift from Middle East-Asia Minor 1 to the more chemical resistant Mediterranean species entering the UK. Predatory mites (Amblyseius swirskii, Transeius montdorensis and Typhlodromalus limonicus were screened for their impact upon various lifestages of B. tabaci Mediterranean species. Approximately 30% of eggs were fed upon by A. swirskii following a 5 day period. Feeding rates slightly decreased for all mite species when feeding on first instar life-stages (27%, 24%, 16% respectively and significantly decreased when feeding on second instars (8.5%, 8.5%, 8.7% respectively. Combining the two mite species (A. swirskii and T. montdorensis increased mortality of Bemisia eggs to 36%. The potential of incorporating the mites into existing control strategies for B. tabaci is discussed.

  4. Resistance to Arrenurus spp. Parasitism in Odonates: Patterns Across Species and Comparisons Between a Resistant and Susceptible Host.

    Science.gov (United States)

    Worthen, Wade B; Hart, Thomas M

    2016-01-01

    Some adult odonates resist parasitism by larval water mites (Arrenurus spp.) with melanotic encapsulation, in which the mite's stylestome is clogged and the mite starves. In summer 2014, we counted the engorged and resisted mites on 2,729 adult odonates sampled by aerial net at 11 water bodies in Greenville Co. and Pickens Co., SC, and tested the hypothesis that the frequency and intensity of resistance correlates with parasite prevalence (the percentage of parasitized hosts). Resistance prevalence (the percentage of parasitized hosts that resisted at least one mite) varied significantly among host species, exceeding 60% for Argia fumipennis(Burmeister) and Celithemis fasciata Kirby but less than 20% for other species. However, neither resistance prevalence nor mean resistance intensity (mean percentage of resisted mites on resisting hosts) correlated with parasite prevalence. We described potential effects of parasitism on host development ofA. fumipennis and Pachydiplax longipennis(Burmeister) by comparing the percent asymmetry of forewing lengths between parasitized and unparasitized individuals. There was no significant difference in asymmetry for either males or females of A. fumipennis, or males of Pa. longipennis(females were not sampled). We also evaluated differences in melanotic encapsulation between A. fumipennis, which readily encapsulates mites in nature, and Pa. longipennis We inserted a 2.0-mm piece of sterile monofilament line into the thorax of captured individuals for 24 h and compared mean gray value scores of inserted and emergent ends using Image-J software. There was no difference in melanotic encapsulation between species.

  5. MITE INCIDENCE AND CROP YIELD IN ZIMBABWE

    African Journals Online (AJOL)

    control, as well as damage and yield of tomatoes were investigated in two important tomato production areas of ... Mutoko, while the pruned and trellised plots had 4.6 and 17.3 mites per leaf. ..... therefore, insecticide deposit on the leaves was.

  6. En el límite

    Directory of Open Access Journals (Sweden)

    Reyes González, José Miguel

    1992-02-01

    Full Text Available Glass: technological limits, physical limits, existential limits as well? Inside or outside? Extreme or combined solutions? Glass architectures separating us from the exterior or uniting us with it? Ideal architectures or those adapted to the surroundings? Different energy costs for different solutions. A continually developing terrestrial atmosphere. Different geographies, artificial metropolis. Will we have to face the obligation to choose within the limits? Different architectures answering these questions are presented in this article.

    El vidrio: límite tecnológico, límite físico. ¿También límite existencial? ¿Dentro o fuera? ¿Soluciones extremas o soluciones mixtas? Arquitecturas de vidrio que nos separan o nos unen al exterior. Arquitecturas ideales, o adaptadas al medio circundante. Diferentes gastos de energía para diferentes planteamientos. Una atmósfera terrestre en continua evolución. Diferentes geografías y metrópolis artificiales. ¿Nos veremos obligados a elegir en el límite? Se exponen aquí diferentes arquitecturas que responden a estos distintos planteamientos.

  7. Respiratory allergy caused by house dust mites

    DEFF Research Database (Denmark)

    Calderón, Moisés A; Linneberg, Allan; Kleine-Tebbe, Jörg

    2015-01-01

    The house dust mite (HDM) is a major perennial allergen source and a significant cause of allergic rhinitis and allergic asthma. However, awareness of the condition remains generally low. This review assesses the links between exposure to HDM, development of the allergic response, and pathologic ...

  8. Control of Varroa jacobsoni Oud. resistant to fluvalinate and amitraz using coumaphos

    OpenAIRE

    Elzen, Patti; Baxter, James; Spivak, Marla; Wilson, William

    2000-01-01

    International audience; We conducted laboratory tests investigating the mortality of mites infesting honey bee colonies in Minnesota after exposure to fluvalinate, amitraz, or coumaphos. Results indicated that these mites were not only resistant to fluvalinate, but also to amitraz. Coumaphos was effective against these resistant mites. A separate field trial was conducted with the same hives as those used in the laboratory test. The field trial supported the laboratory results, showing that m...

  9. There is the second virus that causes tobacco leaf curl disease (not TbLCV-CHI) in the field

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Sequence analysis of virus isolation DNA of tobacco leaf curl disease shows that there is the second geminivirus (not Chinese Tobacco Leaf Curl Virus, TbLCV-CHI) that causes tobacco leaf curl disease in the field in the Guangxi Zhuang Autonomous Region, China. This virus DNA-A contains 2 734 nt. Large intergenic region (LIR) contains 269 nt, the virus sense strand contains 2 open reading frames (ORFs): AV1 (115 aa) and AV2 (coat protein gene, CP, 256 aa), and the complementary sense strand contains 4 ORFs: AC1 (replicase gene, 361 aa), AC2 (transactivator, 134 aa), AC3 (134 aa) and AC4 (97 aa). The virus belongs to one kind of subgroup Ⅲ gemini- viruses from old world, and could be the Chinese tomato yellow leaf curl virus (TYLCV-CHI).

  10. Phylogenetic lineage of Tobacco leaf curl virus in Korea and estimation of recombination events implicated in their sequence variation.

    Science.gov (United States)

    Park, Jungan; Lee, Hyejung; Kim, Mi-Kyung; Kwak, Hae-Ryun; Auh, Chung-Kyoon; Lee, Kyeong-Yeoll; Kim, Sunghan; Choi, Hong-Soo; Lee, Sukchan

    2011-08-01

    New strains of Tobacco leaf curl virus (TbLCV) were isolated from tomato plants in four different local communities of Korea, and hence were designated TbLCV-Kr. Phylogenetic analysis of the sequences of the whole genome and of individual ORFs of these viruses indicated that they are closely related to the Tobacco leaf curl Japan virus (TbLCJV) cluster, which includes Honeysuckle yellow vein virus (HYVV), Honeysuckle yellow vein mosaic virus (HYVMV), and TbLCJV isolates. Four putative recombination events were recognized within these virus sequences, suggesting that the sequence variations observed in these viruses may be attributable to intraspecific and interspecific recombination events involving some TbLCV-Kr isolates, Papaya leaf curl virus (PaLCV), and a local isolate of Tomato yellow leaf curl virus (TYLCV).

  11. Student thinking about the divergence and curl in mathematics and physics contexts

    CERN Document Server

    Baily, Charles; Pattie, Andrew; van Kampen, Paul; De Cock, Mieke

    2015-01-01

    Undergraduate physics students are known to have difficulties with understanding mathematical tools, and with applying their knowledge of mathematics to physical contexts. Using survey statements based on student interviews and written responses to open-ended questions, we investigated the prevalence of correct and incorrect conceptions regarding the divergence and curl of vector fields, among both mathematics and physics students. We compare and contrast pre-instruction responses from intermediate-level E&M students at KU Leuven and the University of St Andrews with post-instruction responses from St Andrews students enrolled in a vector calculus course. In comparing pre- and post-instruction responses from E&M students we see that, although their understanding of the divergence and curl improved, relatively few of them were able to provide completely correct survey responses at mid-semester.

  12. A simple and straightforward expression for curling probe electron density diagnosis in reactive plasmas

    Science.gov (United States)

    Arshadi, Ali; Brinkmann, Ralf Peter; Hotta, Masaya; Nakamura, Keiji

    2017-04-01

    Active plasma resonance spectroscopy (APRS) refers to the family of plasma diagnostic methods which utilize the ability of plasmas to resonate at frequencies close to the plasma frequency. APRS operates by exciting the plasma with a weak RF signal by means of a small electric probe. The response of the plasma is recorded by a network analyzer (NA). A mathematical model is applied to derive characteristics like the electron density and the electron temperature. The curling probe is a promising realization of APRS. The curling probe is well-qualified for the local measurement of the electron density in reactive plasmas. This spiral probe resonates in plasma at a larger density dependent frequency than the plasma frequency. This manuscript represents a simple and straightforward expression relating this resonance frequency to the electron density of the plasma. A good agreement is observed between the proposed expression and the results obtained from previous studies and numerical simulations.

  13. Efficient Assembly of H(div) and H(curl) Conforming Finite Elements

    CERN Document Server

    Rognes, Marie; Logg, Anders; 10.1137/08073901X

    2012-01-01

    In this paper, we discuss how to efficiently evaluate and assemble general finite element variational forms on H(div) and H(curl). The proposed strategy relies on a decomposition of the element tensor into a precomputable reference tensor and a mesh-dependent geometry tensor. Two key points must then be considered: the appropriate mapping of basis functions from a reference element, and the orientation of geometrical entities. To address these issues, we extend here a previously presented representation theorem for affinely mapped elements to Piola-mapped elements. We also discuss a simple numbering strategy that removes the need to contend with directions of facet normals and tangents. The result is an automated, efficient, and easy-to-use implementation that allows a user to specify finite element variational forms on H(div) and H(curl) in close to mathematical notation.

  14. Discovery and demonstration of small circular DNA molecules derived from Chinese tomato yellow leaf curl virus

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Tomato yellow leaf curl viruses belong to Begomoviruses of geminiviruses.In this work, we first found and demonstrated that the small circular DNA molecules were derived from Chinese tomato yellow leaf curl viruses (TYLCV-CHI).These small circular DNA molecules are about 1.3 kb, which are half the full-length of TYLCV-CHI DNA A.It was shown by sequence determination and analysis that there was unknown-origin sequence insertion in the middle of the small molecules.These sequences of unknown-origin were neither homologous to DNA A nor to DNA B, and were formed by recombination of virus DNA and plant DNA.Although various defective molecules contained different unknown-origin sequence insertion, all the molecules contained the intergenic region and part of the AC1(Rep) gene.But they did not contain full ORF.

  15. Poultry red mite (Dermanyssus gallinae) infestation: a broad impact parasitological disease that still remains a significant challenge for the egg-laying industry in Europe.

    Science.gov (United States)

    Sigognault Flochlay, Annie; Thomas, Emmanuel; Sparagano, Olivier

    2017-08-01

    The poultry red mite, Dermanyssus gallinae, has been described for decades as a threat to the egg production industry, posing serious animal health and welfare concerns, adversely affecting productivity, and impacting public health. Research activities dedicated to controlling this parasite have increased significantly. Their veterinary and human medical impact, more particularly their role as a disease vector, is better understood. Nevertheless, red mite infestation remains a serious concern, particularly in Europe, where the prevalence of red mites is expected to increase, as a result of recent hen husbandry legislation changes, increased acaricide resistance, climate warming, and the lack of a sustainable approach to control infestations. The main objective of the current work was to review the factors contributing to this growing threat and to discuss their recent development in Europe. We conclude that effective and sustainable treatment approach to control poultry red mite infestation is urgently required, included integrated pest management.

  16. Effect of Performance Speed on Trunk Movement Control During the Curl-Up Exercise

    Directory of Open Access Journals (Sweden)

    Barbado David

    2015-06-01

    Full Text Available Trunk exercise speed has significant effects on neuro-mechanical demands; however, the influence of a variety of exercise speeds on motor control of the trunk displacement remains unknown. The aim of this study was to assess the effect of performance speed on trunk motion control during the curl-up exercise by analyzing the kinematic variance about the sagittal trajectory. Seventeen subjects volunteered to perform curl-ups at different cadences controlled by a metronome. Standard deviation (SD and range (RG of shoulder girdle medial-lateral displacement (SGML and detrended fluctuation analysis (DFA of SGML were calculated to examine linear variability and long range autocorrelation of medial-lateral upper trunk displacements, respectively. In addition, SD, RG and DFA of centre of pressure medial-lateral displacement (COPML were performed to analyze the behavior of the motor system while controlling trunk displacement. Although SD and RG of COPML increased as speed increased, the curl-up cadence did not have significant effects on SD and RG of SGML. These results suggest that although high speed curl-ups challenged participants’ ability to carry out medial-lateral adjustments, an increase of performance speed did not modify the linear variability about the sagittal trajectory. Regarding DFA, the scaling exponent α of SGML and COPML was higher for the fastest movements, mainly in long term fluctuations. Therefore, to maintain the target trajectory, participants used different strategies depending on performance speed. This is to say, there were less trajectory changes when participants performed the fastest exercises.

  17. Natural association of two different betasatellites with Sweet potato leaf curl virus in wild morning glory (Ipomoea purpurea) in India.

    Science.gov (United States)

    Swapna Geetanjali, A; Shilpi, S; Mandal, Bikash

    2013-08-01

    Wild morning glory (Ipomoea purpurea) was observed to be affected by leaf curl and yellow vein diseases during summer-rainy season of 2009 in New Delhi, India. The virus was experimentally transmitted through whitefly, Bemisia tabaci to I. purpurea that reproduced the two distinct symptoms. Sequence analysis of multiple full-length clones obtained through rolling circle amplification from the leaf curl and yellow vein samples showed 91.8-95.3% sequence identity with Sweet potato leaf curl virus (SPLCV) and the isolates were phylogenetically distinct from those reported from Brazil, China, Japan and USA. Interestingly, two different betasatellites, croton yellow vein mosaic betasatellite and papaya leaf curl betasatellite were found with SPLCV in leaf curl and yellow vein diseases of I. purpurea, respectively. This study is the first report of occurrence of SPLCV in wild morning glory in India. SPLCV was known to infect other species of morning glory; our study revealed that I. purpurea, a new species of morning glory was a natural host of SPLCV. To date, betasatellite associated with SPLCV in Ipomoea spp. is not known. Our study provides evidence of natural association of two different betasatellites with SPLCV in leaf curl and yellow vein diseases of I. purpurea.

  18. Qualitative investigation into students' use of divergence and curl in electromagnetism

    Science.gov (United States)

    Bollen, Laurens; van Kampen, Paul; Baily, Charles; De Cock, Mieke

    2016-12-01

    Many students struggle with the use of mathematics in physics courses. Although typically well trained in rote mathematical calculation, they often lack the ability to apply their acquired skills to physical contexts. Such student difficulties are particularly apparent in undergraduate electrodynamics, which relies heavily on the use of vector calculus. To gain insight into student reasoning when solving problems involving divergence and curl, we conducted eight semistructured individual student interviews. During these interviews, students discussed the divergence and curl of electromagnetic fields using graphical representations, mathematical calculations, and the differential form of Maxwell's equations. We observed that while many students attempt to clarify the problem by making a sketch of the electromagnetic field, they struggle to interpret graphical representations of vector fields in terms of divergence and curl. In addition, some students confuse the characteristics of field line diagrams and field vector plots. By interpreting our results within the conceptual blending framework, we show how a lack of conceptual understanding of the vector operators and difficulties with graphical representations can account for an improper understanding of Maxwell's equations in differential form. Consequently, specific learning materials based on a multiple representation approach are required to clarify Maxwell's equations.

  19. Chopping of near- and mid-infrared radiation using a curled electrostatic MEMS actuator

    Science.gov (United States)

    Dausch, David E.; Goodwin, Scott H.; Exarhos, Gregory J.

    2003-09-01

    An electrostatic MEMS actuator known as the "Artificial Eyelid" can be used as a micromechanical chopper for IR detectors. The actuator structure consists of a curled polymer/metal film stack which is microfabricated and released from an IR transparent substrate. The film stack is uncurled by applying an electric field between the curled film and the transparent fixed electrode on the substrate. These flexible film actuators can act as IR choppers, providing transmission of radiation to the sensor elements when open (curled) and reflection when closed (uncurled). Arrays of actuators were fabricated on ITO-coated glass substrates and ranged in size from 4 x 4 mm to 7.5 x 15 mm with individual elements ranging from 250 to 500 μm on a side. Actuation for devices with average radius of curvature of 120 μ was consistently achieved at 150-170 V operation with 98-100% of the elements functioning and long lifetimes. IR chopper characteristics were measured using a blackbody source and pyroelectric detector by applying sine and square wave voltage to the actuators at a frequency of 30 Hz. The capability of the artificial eyelid for chopping near- and mid-IR radiation, including future fabrication of devices using NiCo2O4 or NiRh2O4 films for IR transparent electrodes, will be discussed.

  20. The Acaricidal Activity of Venom from the Jellyfish Nemopilema nomurai against the Carmine Spider Mite Tetranychus cinnabarinus

    Science.gov (United States)

    Yu, Huahua; Yue, Yang; Dong, Xiangli; Li, Rongfeng; Li, Pengcheng

    2016-01-01

    The carmine spider mite Tetranychus cinnabarinus (T. cinnabarinus) is a common polyphagous pest that attacks crops, vegetables, flowers, and so on. It is necessary to find lead compounds for developing novel, powerful, and environmentally-friendly acaricides as an alternative approach to controlling the carmine spider mite because of the serious resistance and residual agrochemicals in the environment. In addition, the study on the acaricidal activities of marine bioactive substances is comparatively deficient. In the present study, the acaricidal activity of venom (NnFV) from the jellyfish Nemopilema nomurai against the carmine spider mite T. cinnabarinus was determined for the first time. The venom had contact toxicity, and the 24-h LC50-value was 29.1 μg/mL. The mite body wall was affected by the venom, with the mite body having no luster and being seriously shrunken after 24 h. T. cinnabarinus was a potential target pest of NnFV, which had potential as a type of natural bioacaricide. The repellent activity and systemic toxicity of the venom against T. cinnabarinus were also studied. However, NnFV had no repellent activity and systemic toxicity against T. cinnabarinus. PMID:27294957

  1. The Acaricidal Activity of Venom from the Jellyfish Nemopilema nomurai against the Carmine Spider Mite Tetranychus cinnabarinus

    Directory of Open Access Journals (Sweden)

    Huahua Yu

    2016-06-01

    Full Text Available The carmine spider mite Tetranychus cinnabarinus (T. cinnabarinus is a common polyphagous pest that attacks crops, vegetables, flowers, and so on. It is necessary to find lead compounds for developing novel, powerful, and environmentally-friendly acaricides as an alternative approach to controlling the carmine spider mite because of the serious resistance and residual agrochemicals in the environment. In addition, the study on the acaricidal activities of marine bioactive substances is comparatively deficient. In the present study, the acaricidal activity of venom (NnFV from the jellyfish Nemopilema nomurai against the carmine spider mite T. cinnabarinus was determined for the first time. The venom had contact toxicity, and the 24-h LC50-value was 29.1 μg/mL. The mite body wall was affected by the venom, with the mite body having no luster and being seriously shrunken after 24 h. T. cinnabarinus was a potential target pest of NnFV, which had potential as a type of natural bioacaricide. The repellent activity and systemic toxicity of the venom against T. cinnabarinus were also studied. However, NnFV had no repellent activity and systemic toxicity against T. cinnabarinus.

  2. Resistencia de cuatro poblaciones del acaro (Tetranychus urticae Koch. a propargite en rosa de corte (Rosa x hybrida en el Estado de México, México Resistance of four population mites (Tetranychus urticae Koch. to propargite in cut rose (Rosa x hybrida in the State of Mexico, Mexico

    Directory of Open Access Journals (Sweden)

    Agustín Robles-Bermúdez

    2012-07-01

    Full Text Available Resumen La araña roja, Tetranychus urticae Koch., es una de las plagas más importantes de la rosa de corte, (Rosa x hybrida, en el Estado de México y su combate se realiza principalmente mediante el uso de acaricidas como el propargite; mismo que los productores usaron inicialmente con resultados satisfactorios y actualmente no controla esta plaga. Con el objetivo de estimar el nivel de resistencia a dicho acaricida, en el año 2007 se evaluó su respuesta a dicho acaricida en poblaciones provenientes de Coatepec Harinas, Tenancingo, Villa Guerrero y Zumpahuacán, Estado de México. De cada localidad se recolectaron al menos 4000 ninfas y 2 000 adultos en el cultivo de rosa de corte bajo invernadero y se reprodujeron hasta F1 para realizar los bioensayos. Se determinó el rango de dosis que eliminaba el 0 al 100% de los individuos tratados (ventana biológica. Posteriormente se incluyeron de cinco a siete concentraciones que cubrieron dicho rango. Se realizaron cinco repeticiones cuatro en días consecutivos diferentes. Las poblaciones de araña roja provenientes de Coatepec Harinas (RR95= 7.9x, Villa Guerrero (RR95=1.3x y Zumpahuacán (RR95= 11 x se consideran susceptibles a propargite; mientras que la población de Tenancingo (RR95 = 90.1 x se considera resistente a dicho acaricida.The spider mite, Tetranychus urticae Koch., is one of the most important pests of cut rose (Rosa x hybrida in the State of México and, its primary control it's through the use of acaricides, such as propargite; the producers initially used it with satisfactory results and currently it does not control this pest anymore. In order to estimate the level of resistance to that acaricide, in 2007, its response to this acaricide was assessed in populations from Coatepec Harinas, Tenancingo, Villa Guerrero and Zumpahuacán, State of México. In each locality at least 4 000 nymphs and 2 000 adults were collected in the cut rose cultivation in greenhouses and were

  3. A house dust mite allergen homologue from poultry red mite Dermanyssus gallinae (De Geer).

    Science.gov (United States)

    Nisbet, A J; Huntley, J F; Mackellar, A; Sparks, N; McDevitt, R

    2006-08-01

    Tropomyosin is an allergenic, actin-binding protein and a proposed vaccine candidate from several species of parasite. Tropomyosin cDNA, obtained by polymerase chain reaction (PCR) amplification from Dermanyssus gallinae RNA, encoded a predicted protein with 89% and 88% identity to tropomyosins from the ticks Boophilus microplus and Haemaphysalis longicornis, respectively, and 85% identity to the house dust mite (HDM) tropomyosin Der p 10. Mouse antibodies raised against HDM tropomyosin reacted with a band of 38 kDa on Western blots of D. gallinae extract, consistent with the molecular masses of acarine tropomyosins and the putative product of the cDNA encoding D. gallinae tropomyosin. When the same preparation of D. gallinae proteins was used in Western blots with serum from infested hens, the IgY component of the serum bound to a number of mite proteins, but not to tropomyosin, indicating that hens are not directly exposed to this allergen during a natural infestation. Immunolocalization of tropomyosin in mites indicated a ubiquitous distribution of the molecule in mite tissues. Immunolocalization and Western blotting also indicated that poultry red mites ingest host IgY.

  4. Salivary proteins of spider mites suppress defenses in Nicotiana benthamiana and promote mite reproduction.

    Science.gov (United States)

    Villarroel, Carlos A; Jonckheere, Wim; Alba, Juan M; Glas, Joris J; Dermauw, Wannes; Haring, Michel A; Van Leeuwen, Thomas; Schuurink, Robert C; Kant, Merijn R

    2016-04-01

    Spider mites (Tetranychidae sp.) are widely occurring arthropod pests on cultivated plants. Feeding by the two-spotted spider mite T. urticae, a generalist herbivore, induces a defense response in plants that mainly depends on the phytohormones jasmonic acid and salicylic acid (SA). On tomato (Solanum lycopersicum), however, certain genotypes of T. urticae and the specialist species T. evansi were found to suppress these defenses. This phenomenon occurs downstream of phytohormone accumulation via an unknown mechanism. We investigated if spider mites possess effector-like proteins in their saliva that can account for this defense suppression. First we performed an in silico prediction of the T. urticae and the T. evansi secretomes, and subsequently generated a short list of candidate effectors based on additional selection criteria such as life stage-specific expression and salivary gland expression via whole mount in situ hybridization. We picked the top five most promising protein families and then expressed representatives in Nicotiana benthamiana using Agrobacterium tumefaciens transient expression assays to assess their effect on plant defenses. Four proteins from two families suppressed defenses downstream of the phytohormone SA. Furthermore, T. urticae performance on N. benthamiana improved in response to transient expression of three of these proteins and this improvement was similar to that of mites feeding on the tomato SA accumulation mutant nahG. Our results suggest that both generalist and specialist plant-eating mite species are sensitive to SA defenses but secrete proteins via their saliva to reduce the negative effects of these defenses.

  5. Real-time PCR protocols for the quantification of the begomovirus tomato yellow leaf curl Sardinia virus in tomato plants and in its insect vector.

    Science.gov (United States)

    Noris, Emanuela; Miozzi, Laura

    2015-01-01

    Tomato yellow leaf curl Sardinia virus (TYLCSV) (Geminiviridae) is an important pathogen, transmitted by the whitefly Bemisia tabaci, that severely affects the tomato production in the Mediterranean basin. Here, we describe real-time PCR protocols suitable for relative and absolute quantification of TYLCSV in tomato plants and in whitefly extracts. Using primers and probe specifically designed for TYLCSV, the protocols for relative quantification allow to compare the amount of TYLCSV present in different plant or whitefly samples, normalized to the amount of DNA present in each sample using endogenous tomato or Bemisia genes as internal references. The absolute quantification protocol allows to calculate the number of genomic units of TYLCSV over the genomic units of the plant host (tomato), with a sensitivity of as few as ten viral genome copies per sample. The described protocols are potentially suitable for several applications, such as plant breeding for resistance, analysis of virus replication, and virus-vector interaction studies.

  6. Intestinal proteases of free-living and parasitic astigmatid mites.

    Science.gov (United States)

    Holt, Deborah C; Burgess, Stewart T G; Reynolds, Simone L; Mahmood, Wajahat; Fischer, Katja

    2013-02-01

    Among arthropod pests, mites are responsible for considerable damage to crops, humans and other animals. However, detailed physiological data on these organisms remain sparse, mainly because of their small size but possibly also because of their extreme diversity. Focusing on intestinal proteases, we draw together information from three distinct mite species that all feed on skin but have separately adapted to a free-living, a strictly ecto-parasitic and a parasitic lifestyle. A wide range of studies involving immunohistology, molecular biology, X-ray crystallography and enzyme biochemistry of mite gut proteases suggests that these creatures have diverged considerably as house dust mites, sheep scab mites and scabies mites. Each species has evolved a particular variation of a presumably ancestral repertoire of digestive enzymes that have become specifically adapted to their individual environmental requirements.

  7. Músicas al límite

    OpenAIRE

    2007-01-01

    Los límite de la música dependen de su propia definición y de su carácter humano. El empleo de sonido animal ha sido una constante a lo largo del tiempo y es una variante del empleo o miméis de sonidos naturales. La ampliación de los sonidos musicales hacia el ruido es otro de los límites desbordados ya sea ruidoo natural ,que nos lleva a la concepción moderna del paisaje sonoro o artificial que va desde los distintos bruitismos al sonido electrónico. También la naturaleza matemát...

  8. Genetics and Genomics of Cotton Leaf Curl Disease, Its Viral Causal Agents and Whitefly Vector: A Way Forward to Sustain Cotton Fiber Security

    Directory of Open Access Journals (Sweden)

    Mehboob-ur- Rahman

    2017-07-01

    Full Text Available Cotton leaf curl disease (CLCuD after its first epidemic in 1912 in Nigeria, has spread to different cotton growing countries including United States, Pakistan, India, and China. The disease is of viral origin—transmitted by the whitefly Bemisia tabaci, which is difficult to control because of the prevalence of multiple virulent viral strains or related species. The problem is further complicated as the CLCuD causing virus complex has a higher recombination rate. The availability of alternate host crops like tomato, okra, etc., and practicing mixed type farming system have further exaggerated the situation by adding synergy to the evolution of new viral strains and vectors. Efforts to control this disease using host plant resistance remained successful using two gene based-resistance that was broken by the evolution of new resistance breaking strain called Burewala virus. Development of transgenic cotton using both pathogen and non-pathogenic derived approaches are in progress. In future, screening for new forms of host resistance, use of DNA markers for the rapid incorporation of resistance into adapted cultivars overlaid with transgenics and using genome editing by CRISPR/Cas system would be instrumental in adding multiple layers of defense to control the disease—thus cotton fiber production will be sustained.

  9. Genetics and Genomics of Cotton Leaf Curl Disease, Its Viral Causal Agents and Whitefly Vector: A Way Forward to Sustain Cotton Fiber Security.

    Science.gov (United States)

    Rahman, Mehboob-Ur-; Khan, Ali Q; Rahmat, Zainab; Iqbal, Muhammad A; Zafar, Yusuf

    2017-01-01

    Cotton leaf curl disease (CLCuD) after its first epidemic in 1912 in Nigeria, has spread to different cotton growing countries including United States, Pakistan, India, and China. The disease is of viral origin-transmitted by the whitefly Bemisia tabaci, which is difficult to control because of the prevalence of multiple virulent viral strains or related species. The problem is further complicated as the CLCuD causing virus complex has a higher recombination rate. The availability of alternate host crops like tomato, okra, etc., and practicing mixed type farming system have further exaggerated the situation by adding synergy to the evolution of new viral strains and vectors. Efforts to control this disease using host plant resistance remained successful using two gene based-resistance that was broken by the evolution of new resistance breaking strain called Burewala virus. Development of transgenic cotton using both pathogen and non-pathogenic derived approaches are in progress. In future, screening for new forms of host resistance, use of DNA markers for the rapid incorporation of resistance into adapted cultivars overlaid with transgenics and using genome editing by CRISPR/Cas system would be instrumental in adding multiple layers of defense to control the disease-thus cotton fiber production will be sustained.

  10. Oribatid mites in a changing world

    OpenAIRE

    2011-01-01

    The main scope of this thesis is to illustrate the validity of oribatid mites as tools for palaeoecological reconstructions. Palaeoecology studies the responses of past organisms to past environmental changes. This can be accomplished through the use of biological proxies, which are indicators of past conditions. The search for additional means of distinguishing climate change has only recently led to the use of other commonly found biological proxies such ...

  11. Predatory mite fauna in Aegean vineyards

    OpenAIRE

    GÖVEN, Mehmet Ali; ÇOBANOĞLU, Sultan; GÜVEN, Bilgin

    2010-01-01

    This study was carried out between 1997-2004 in vineyard areas in Manisa, İzmir, Denizli, Muğla and Çanakkale (Bozcaada) provinces of the Aegean region to determine biological control possibilities against phytophagous mites. Sampling was conducted from May to October. Most of the vineyards were sampled three times during the growing season and 50 leaves were collected randomly in each vineyard. Colomerus vitis (Pagenstecher) and Calepitrimerus vitis (Nalepa)were determined ...

  12. Health effects of predatory beneficial mites and wasps in greenhouses

    DEFF Research Database (Denmark)

    Bælum, Jesper; Enkegaard, Annie; Doekes, Gert

    2007-01-01

    A three-year study of 579 greenhouse workers in 31 firms investigated the effect of four different beneficial arthropods. It was shown that the thrips mite Amblyseeius cucumeris and the spider mite predator Phytoseiulus persimilis may cause allergy measured by blood tests as well as eye and nose...... symptoms. No effect was seen by the predator wasp Aphidius colemani nor the predator mite Hypoaspis miles and no effect on lung diseases were seen....

  13. Health effects of predatory beneficial mites and wasps in greenhouses

    DEFF Research Database (Denmark)

    Bælum, Jesper; Enkegaard, Annie; Doekes, Gert;

    A three-year study of 579 greenhouse workers in 31 firms investigated the effect of four different beneficial arthropods. It was shown that the thrips mite Amblyseeius cucumeris and the spider mite predator Phytoseiulus persimilis may cause allergy measured by blood tests as well as eye and nose...... symptoms. No effect was seen by the predator wasp Aphidius colemani nor the predator mite Hypoaspis miles and no effect on lung diseases were seen....

  14. Evidence for horizontal transfer of Wolbachia by a Drosophila mite.

    Science.gov (United States)

    Brown, Amy N; Lloyd, Vett K

    2015-07-01

    Mites are common ectoparasites of Drosophila and have been implicated in bacterial and mobile element invasion of Drosophila stocks. The obligate endobacterium, Wolbachia, has widespread effects on gene expression in their arthropod hosts and alters host reproduction to enhance its survival and propagation, often with deleterious effects in Drosophila hosts. To determine whether Wolbachia could be transferred between Drosophila melanogaster laboratory stocks by the mite Tyrophagus putrescentiae, mites were introduced to Wolbachia-infected Drosophila vials. These vials were kept adjacent to mite-free and Wolbachia-uninfected Drosophila stock vials. The Wolbachia infection statuses of the infected and uninfected flies were checked from generation 1 to 5. Results indicate that Wolbachia DNA could be amplified from mites infesting Wolbachia-infected fly stocks and infection in the previously uninfected stocks arose within generation 1 or 2, concomitant with invasion of mites from the Wolbachia-infected stock. A possible mechanism for the transfer of Wolbachia from flies to mites and vice versa, can be inferred from time-lapse photography of fly and mite interactions. We demonstrated that mites ingest Drosophila corpses, including Wolbachia-infected corpses, and Drosophila larva ingest mites, providing possible sources of Wolbachia infection and transfer. This research demonstrated that T. putrescentiae white mites can facilitate Wolbachia transfer between Drosophila stocks and that this may occur by ingestion of infected corpses. Mite-vectored Wolbachia transfer allows for rapid establishment of Wolbachia infection within a new population. This mode of Wolbachia introduction may be relevant in nature as well as in the laboratory, and could have a variety of biological consequences.

  15. Relationship between the ability to penetrate complex webs of Tetranychus spider mites and the ability of thread-cutting behavior in phytoseiid predatory mites

    NARCIS (Netherlands)

    Shimoda, T.; Kishimoto, H.; Takabayashi, J.; Amano, H.; Dicke, M.

    2010-01-01

    Predatory mites, that are important natural enemies of Tetranychus spider mites, are less hindered by complex webs of the spider mites than are other predatory mites that are natural enemies of other pest herbivores. This can be partly explained by their chaetotaxy, a morphological protection agains

  16. EFFICACY OF 15% FORMIC ACID ON VARROA MITES IN DIFFERENT FORMS OF APPLICATION

    Directory of Open Access Journals (Sweden)

    M MUŽA

    2002-05-01

    Full Text Available Varroa destructor is a parasitic mite of the honeybee, Apis mellifera, responsible for reduced honey and brood production, higher bee mortality in winter. Because the resistance to the acaricides and they residues to bee products, alternative products and methods have been used against Varroa. One of this methods is treatment with formic acid. Formic acid induce to Varroa mite in brood and do not leave any residues in products. Concentric formic acid (60-85% is very effective, but at higher air temperature, it has influence on bee. In the last few years, except concentric formic acid, 15 % formic acid was recommended as control of varroosis. Diluted formic acid (15% reduced the bee response to treatment. In treatment with 15% formic acid, higher air temperature and different forms of application have positive influence to they function (65 – 95%.

  17. House dust mite control measures for asthma: systematic review

    DEFF Research Database (Denmark)

    Gøtzsche, Peter C.; Johansen, Helle Krogh

    2008-01-01

    The major allergen in house dust comes from mites. We performed a systematic review of the randomized trials that had assessed the effects of reducing exposure to house dust mite antigens in the homes of people with mite-sensitive asthma, and had compared active interventions with placebo...... improved (relative risk 1.01, 95% CI 0.80-1.27), asthma symptom scores (standardized mean difference -0.04, 95% CI -0.15 to 0.07) or in medication usage (standardized mean difference -0.06, 95% CI -0.18 to 0.07). Chemical and physical methods aimed at reducing exposure to house dust mite allergens cannot...

  18. HOUSE DUST MITE ALLERGY IN VIEW OF MOLECULAR ALLERGOLOGY

    Directory of Open Access Journals (Sweden)

    E. S. Korovkina

    2012-01-01

    Full Text Available Abstract. Incidence of allergic diseases is increased over last years. House dust is considered a major risk factor of allergic sensitization which plays an important role in development of allergic rhinitis, bronchial asthma, atopic dermatitis. Dust mites in the home comprise a large part of domestic allergens. Dermatophagoides pteronyssinus, Dermatophagoides farinae, Euroglyphus maynei, Lepidoglyphus destructor, Blomia tropicalis are most important in this respect. Der p 1 and Der p 2 are regarded as major house dust mite allergens. Recent studies concerned induction of IgE responses against mite tropomyosin (Der p 10, an allergen occurring in mites which exhibits high cross-reactivity with tropomyosins from a variety of sea foods (e.g. shrimps, as well as human tropomyosins. Allergen-specific immunotherapy (ASIT represents the only causative approach to allergy treatment in such cases. From this viewpoint, a quantitation of specific IgЕ against major house dust mite allergens would be necessary to predict ASIT efficiency. Treatment by house dust mites allergen extracts is effective in management of allergic rhinitis and mild asthma. A component-resolved diagnostic (CRD with purified house-dust mites allergens allows to discriminate patients who were mostly sensitized to the major house dust mites allergens (e.g. Der p 10, tropomyosin. The component-resolved diagnostics could be performed before starting the allergen-specific immunotherapy by mite allergens, in order to avoid unresponsiveness to this mode of therapy.

  19. Mites associated with stored grain commodities in Benin, West Africa.

    Science.gov (United States)

    Zannou, Ignace D; Adebo, Habib O; Zannou, Elisabeth; Hell, Kerstin

    2013-12-01

    After insects, mites are the major arthropod pests that inhabit stored agricultural products worldwide. To determine the acarofauna that infests cowpea, maize, paddy rice and sorghum in Benin (West Africa), surveys were conducted in some principal markets (Dantokpa, Glazoue and Parakou) of this country. A total of 555 samples of grains and debris were collected in May and September 2011. More than 56 species belonging to 24 mite families were recorded in the four products. These mite species included predators, parasites, fungivorous, phytophagous and other groups whose feeding habits are not well known. The family Cheyletidae was the most prevalent and the most diverse predatory mite family encountered, in which Cheyletus malaccensis Oudemans was the most abundant species. Several families of mite pests and mites responsible for allergies (Acaridae, Glycyphagidae, Pyroglyphidae, Pyemotidae and Saproglyphidae) were also detected. The three most dominant and frequent species were C. malaccensis, Suidasia nesbitti (Hughes) and Suidasia sp. Statistical analysis showed that densities of these three mite species were higher in Parakou than in Glazoue and Dantokpa, on one hand, and higher in debris than in grains, on the other hand. The densities of S. nesbitti and Suidasia sp. decreased significantly during the dry season, whereas C. malaccensis remained stable throughout the two samplings. Of all grains, sorghum was the least infested with mites. This study shows that in Benin mites are present in stored agricultural products to which they cause serious damage, and may cause various allergies to people.

  20. Evidence refuting the contribution of the fungus Aspergillus penicillioides to the allergenicity of the house dust mite Dermatophagoides pteronyssinus.

    Science.gov (United States)

    Hay, D B; Hart, B J; Douglas, A E

    1992-01-01

    This communication demonstrates unequivocally that the fungi associated with house dust mites do not contribute to mite allergenicity. The evidence is twofold: first, larval mites which lack fungi have allergen profiles indistinguishable from fungus-bearing adult mites. Second, the allergen profile of experimentally-derived fungus-free adult mites and mites re-fed the fungus Aspergillus penicillioides are identical.

  1. Tyrophagus putrescentiae mites grown in dog food cultures and the effect mould growth has on mite survival and reproduction.

    Science.gov (United States)

    Canfield, Michael S; Wrenn, William J

    2010-02-01

    The purposes of this study were to determine whether the storage mite, Tyrophagus putrescentiae, could survive and thrive on dog food and if mould growth was important to their survival. All of the chambers (n = 42) were started with 10 female mites and evaluated every other day for mite survival and for the spontaneous development of mould. Ten chambers tested the effect of low moisture on mite survival. Eight chambers were used as positive and negative controls (n = 4 each); positive control mites were fed Fleischmann's((R)) yeast and negative controls had no food source. Three dog foods were evaluated in the same manner. Four chambers had food but mould development was limited by replacing the food kernel every 48 h and four chambers were allowed to grow mould. Mites grown in chambers without moisture died from desiccation within 5 days. The termination point was day 34 when all mites in the negative control group (moisture but no food) died. Although T. putrescentiae survived and grew on all three commercial dog foods, there was no statistically significant difference in mites counts among the dog foods (P dog food. The study demonstrated that the presence of mould positively influences mite viability, while low relative humidity can result in detrimental consequences for T. putrescentiae.

  2. Occupational exposure to allergenic mites in a Polish zoo.

    Science.gov (United States)

    Solarz, Krzysztof; Szilman, Piotr; Szilman, Ewa

    2004-01-01

    The study was carried out from April 2000-March 2001. During this period 49 samples of dust, litter, debris and residues from cages and run-offs of mammals, birds and reptiles in the Silesian Zoo, were examined for the presence of mites, especially the allergenic taxa. Mites were extracted using the Berlese method and preserved in 70 % ethanol. For identification, the mites were mounted in Hoyer's medium on microscope slides. Mites were found in 44 of 49 samples analyzed (89.8 %). A total of 5,097 mites were collected, from which 60.3 % were found in samples collected in spring, whereas only 13 % in summer and 24.1 % in autumn. The remaining 2.6 % of the total mite population was found in winter. Majority of mites (82.7 %) were collected from aviaries of macaws and cockatiels (Ara ararauna and Nymphicus hollandicus). A total of 10 species of astigmatid mites were identified that belong to 4 families--Acaridae, Glycyphagidae, Anoetidae and Pyroglyphidae. Generally, the allergenic mites of the order Astigmata constituted 49.5 % of the total count. Among them Acarus farris was predominant (34 % of the total count), followed by Tyrophagus putrescentiae (4.7 %), Caloglyphus sp. (4.35 %) and Acarus immobilis (4.31 %). Dermatophagoides farinae, the house-dust-mite species, was for the first time found in this environment. D. farinae (0.05 % of the total population) was associated with parrots, canids and artiodactyls. Summarizing, it should be stressed, that cages and run-offs of different mammals, aviaries of parrots and terrariums of snakes are important sources of some allergenic mites, especially A. farris and T. putrescentiae, that might cause allergies in workers.

  3. Infection of Psoroptes mites with the fungus Metarhizium anisopliae.

    Science.gov (United States)

    Brooks, A J; Wall, R

    2001-01-01

    The astigmatid mite, Psoroptes ovis (Hering) (Acari: Psoroptidae), is an obligatory ectoparasite that causes psoroptic mange in a range of domesticated animals, particularly sheep, where the clinical disease is known as sheep scab. A series of laboratory assays were used to assess the use of the fungus, Metarhizium anisopliae (Metchnikoff) (Deuteromycotina: Hyphomycetes) as a biocontrol agent for P. ovis derived from rabbits (syn. P. cuniculi). The immersion of mites in a suspension of conidia of M. anisopliae resulted in the acquisition of fatal infections. The number of mites which developed infections increased significantly with the increasing concentration of the conidial suspension to which they were exposed; 77% of mites developed infections when exposed to the highest concentration used (1 x 10(8) conidia ml(-1)). Controls developed no fungal infections. Mites allowed simply to walk across a surface which had been treated with a suspension of conidia also acquired fungal infections; the number infected was again related to the concentration of conidia present. After contact for 24 h with a surface treated with 1 x 10(8) conidia ml(-1), 73% of the mites became infected. To determine whether dead infected mites could act as sources of infection, infected cadavers were placed in chambers with live uninfected mites. The uninfected mites acquired fatal infections from the cadavers; a higher ratio of infected cadavers to uninfected mites resulted in greater transmission of infection. The time after death of the infected cadaver was also an important factor influencing the number infected, 5-day-old cadavers were the most infective and 18-day-old cadavers the least infective. The results indicate that M. anisopliae is a good candidate control agent for Psoroptes mites.

  4. Effect of ambient storage on the quality characteristics of aerobically packaged fish curls incorporated with different flours.

    Science.gov (United States)

    Raja, Waseem Hussain; Kumar, Sunil; Bhat, Zuhaib Fayaz; Kumar, Pavan

    2014-01-01

    The present study was conducted to evaluate the effect of ambient storage on the quality attributes of aerobically packaged fish curls incorporated with optimum levels of different flours. The curls were developed by extrusion technology using fish meat (Catla catla). The fish curls containing optimum levels of different flours viz. 20 percent corn flour, 10 percent black gram flour and 10 percent peanut flour were compared with the control snacks containing 30 percent rice flour and assessed for storage quality and shelf life at ambient temperature. The curls were aerobically packaged in LDPE (low density polyethylene) pouches and evaluated for various physicochemical, microbiological and sensory parameters. Mean values of pH of all the curls showed significantly (p flour incorporated samples, 6.36 ± 0.01 on day 0 and 6.14 ± 0.01 on day 28 for black gram flour incorporated samples, 6.57 ± 0.007 on day 0 and 6.34 ± 0.01 on day 28 for peanut flour incorporated samples). TBARS (mg malonaldehyde/kg), total plate count (log cfu/g) and yeast and mould count (log cfu/g) for the control as well as treatment samples showed significantly (p flours were acceptable up to 21 days of ambient storage within the LDPE pouches.

  5. Coat protein promoter from cotton leaf curl virus is not a tissue-specifically expressed promoter

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Geminivirus is a kind of single-stranded DNA virus. Experimental results from tomato golden mosaic virus (TGMV) showed that expression pattern of coat protein gene (cp) promoter was phloem specifically expressed. In this note, the studies on cp promoter of cotton leaf curl virus (CLCuV) which is found and identified recently suggest that the promoter is not phloem specifically expressed. The expressing activity of gus gene driven by the promoter exists not only in phloem but also in mesophyll tissues and root tip meristem. Transient expression suggests that cp promoter transactivated by AC2 shows expressing activity in mesophyll and vascular tissue of leaf vein.

  6. Attentional Demands in the Execution Phase of Curling in Novices and Experts

    Directory of Open Access Journals (Sweden)

    Véronique Shank

    2013-03-01

    Full Text Available The purpose of this study was to determine the attentional demands of a curling delivery using a dual-task procedure. Skilled and novice curlers were asked to perform take outs and draws while attentional demands were measured using reaction time (RT in the different phases of the throw. Results showed attentional demands for the draw and take out were highest at the beginning of the delivery. Compared to the draw, a significant rise of RT was shown at the end of the take out shot. Shot success was significantly higher for the take out condition in expert compared to novice curlers.

  7. Curling up two spatial dimensions with SU(1,1)/U(1)

    Energy Technology Data Exchange (ETDEWEB)

    Gell-Mann, M.; Zwiebach, B.

    1984-11-01

    It is seen that a nonlinear sigma model based on the noncompact coset space SU(1,1)/U(1) can curl up two spatial dimensions into a topologically noncompact surface of finite area with a compact U(1) isometry group. This mechanism can be used for several higher-dimensional supergravity theories. In particular, chiral N = 2, D = 10 supergravity would reduce to an N = 1, D = 8 theory in which the masslessness of fermions does not depend only on supersymmetry. Further reduction to four dimensions is possible.

  8. Parallel H1-based auxiliary space AMG solver for H(curl) problems

    Energy Technology Data Exchange (ETDEWEB)

    Kolev, T V; Vassilevski, P S

    2006-06-30

    This report describes a parallel implementation of the auxiliary space methods for definite Maxwell problems proposed in [4]. The solver, named AMS, extends our previous study [7]. AMS uses ParCSR sparse matrix storage and the parallel AMG (algebraic multigrid) solver BoomerAMG [1] from the hypre library. It is designed for general unstructured finite element discretizations of (semi)definite H(curl) problems discretized by Nedelec elements. We document the usage of AMS and illustrate its parallel scalability and overall performance.

  9. Fatal poisoning by Rumex crispus (curled dock): pathological findings and application of scanning electron microscopy.

    Science.gov (United States)

    Reig, R; Sanz, P; Blanche, C; Fontarnau, R; Dominguez, A; Corbella, J

    1990-10-01

    A case of fatal poisoning due to ingestion of the plant Rumex crispus (curled dock) is described. The patient, a 53-year-old male, presented with gastrointestinal symptoms, severe hypocalcemia, metabolic acidosis and acute hepatic insufficiency. Despite therapeutic measures, the patient died 72 h after ingestion of the plant material. Noteworthy among the pathological findings were centrolobular hepatic necrosis and birefringent crystals in the liver and kidneys that were identified by histochemical techniques and scanning electron microscopy. These observations are compared with other reports in the medical literature, with an emphasis on the risk involved in the use of these plants for culinary or medicinal purposes.

  10. Size of predatory mites and refuge entrance determine success of biological control of the coconut mite

    NARCIS (Netherlands)

    da Silva, F.R.; de Moraes, G.J.; Lesna, I.; Sato, Y.; Vasquez, C.; Hanna, R.; Sabelis, M.W.; Janssen, A.

    2016-01-01

    Predators face the challenge of accessing prey that live in sheltered habitats. The coconut mite Aceriaguerreronis Keifer (Acari: Eriophyidae) lives hidden beneath the perianth, which is appressed to the coconut fruit surface, where they feed on the meristematic tissue. Its natural enemy, the predat

  11. Genotype to phenotype, the molecular and physiological dimensions of resistance in arthropods

    NARCIS (Netherlands)

    Feyereisen, R.; Dermauw, W.; Van Leeuwen, T.

    2015-01-01

    The recent accumulation of molecular studies on mutations in insects, ticks and mites conferring resistance to insecticides, acaricides and biopesticides is reviewed. Resistance is traditionally classified by physiological and biochemical criteria, such as target-site insensitivity and metabolic res

  12. 中国男子冰壶队与欧美强队扫冰技术能力对比--以2014男子冰壶世界锦标赛为例%Technical Ability Comparative of Sweeping of Chinese Curling Male Team and Euro-American Curling Strong Teams--An Example of 2014 World Curling Male Championship

    Institute of Scientific and Technical Information of China (English)

    马永俊; 牛晓暹; 臧荣海; 许水生

    2014-01-01

    冰壶运动中扫冰技术是对比赛过程产生影响的重要因素。利用文献资料、现场观察等研究方法,对2014男子冰壶世界锦标赛中国队与欧美强队扫冰技术能力进行对比分析,从中找出中国男子冰壶队与欧美强队在扫冰技术能力上的差别,提高中国男子冰壶队竞赛成绩。结果表明:扫冰技术在冰壶比赛中极为重要,对比赛的过程产生重要的影响;中国队与欧美强队相比扫冰技术能力相对较弱;在队投壶技术的稳定性方面中国队比欧美强要好。建议中国队在扫冰技术方面进行针对性训练,加强对冰壶运动轨迹产生影响因素的综合理解认识;增强扫冰技术团队配合能力;提高扫冰技术专项力量训练。%Sweeping is an important factor to influence a process of a game in curling,with the use the methods of literature,field observation and so on. By comparing analyzing on the sweeping technical ability of Chinese curling male team and Euro-American Curling strong teams,find out the difference of technical ability of Chinese curling male team and Euro-American Curling strong teams,to improve the performance of Chinese curling male team. The results show:sweeping technology is very important in curling competition,and have an important impact on the process of games;The sweeping technical ability of Chinese Team is relatively weak to Europe-American strong teams;The stability of throwing curling technology of Chinese Team is better than Europe-American strong teams. Suggest Chinese to have targeted training in sweeping technology, strengthen the comprehensive understanding of curling motion track;Enhance the cooperated ability of sweeping technology;Improve the special strength training of sweeping technology.

  13. Allergy to mites : relation to lung function and airway hyperresponsiveness

    NARCIS (Netherlands)

    van der Heide, S; Dubois, AEJ; Kauffman, HF; de Monchy, JGR

    1998-01-01

    Exposure to house-dust-mite allergens is an important cause of allergic reactions in sensitized patients. In community-based studies, sensitization to house-duct mites, as ascertained by a positive skin test or by an increased allergen-specific IgE level in serum, is associated with both diminished

  14. Checklist of the Oribatid Mites of the Netherlands (Acari: Oribatida)

    NARCIS (Netherlands)

    Siepel, H.; Zaitsev, A.; Berg, M.

    2009-01-01

    More than fifty years ago Van der Hammen published the last checklist of oribatid mites (or moss mites) for the Netherlands. Since then the species number has almost doubled to 318 species, of which 100 are presented here for the first time. Brief data on occurence and nomenclature are provided for

  15. Ecology, life history and management of tropilaelaps mites

    Science.gov (United States)

    Parasitic mites are the major threat of the Western honey bee, Apis mellifera. For much of the world, Varroa destructor single-handedly inflicts unsurmountable problems to A. mellifera beekeeping. However, A. mellifera in Asia is also faced with another genus of destructive parasitic mite, Tropilae...

  16. Invasion of Varroa mites into honey bee brood cells.

    NARCIS (Netherlands)

    Boot, W.J.

    1995-01-01

    The parasitic mite Varroa-jacobsoni is one of the most serious pests of Western honey bees, Apis mellifera. The mites parasitize adult bees, but reproduction only occurs while parasitizing on honey bee brood. Invasion into a drone or a worker cell is therefore a crucial step in the life of Varroa m

  17. Induction of atopic dermatitis by inhalation of house dust mite

    NARCIS (Netherlands)

    Tupker, RA; DeMonchy, JGR; Coenraads, PJ; vanderMeer, JB

    Background: The pathogenetic role of house dust mite in atopic dermatitis remains controversial. Recent studies have shown that intensive epicutaneous contact of house dust mite allergen with premanipulated skin may induce dematitis. It is, however, uncertain whether such conditions are met during

  18. IPM potentials of microbial pathogens and diseases of mites

    NARCIS (Netherlands)

    van der Geest, L.P.S.; Ciancio, A.; Mukerji, K.G.

    2010-01-01

    An overview is given of diseases in mites, caused by infectious microorganisms. Many pathogens play an important role in the regulation of natural populations of mite populations and are for this reason subject of research on the feasibility to develop such pathogens to biological control agents. Se

  19. Induction of atopic dermatitis by inhalation of house dust mite

    NARCIS (Netherlands)

    Tupker, RA; DeMonchy, JGR; Coenraads, PJ; vanderMeer, JB

    1996-01-01

    Background: The pathogenetic role of house dust mite in atopic dermatitis remains controversial. Recent studies have shown that intensive epicutaneous contact of house dust mite allergen with premanipulated skin may induce dematitis. It is, however, uncertain whether such conditions are met during n

  20. Citrus rootstocks influence the population densities of pest mites

    Directory of Open Access Journals (Sweden)

    Rafael Rocha da Silva

    2016-01-01

    Full Text Available Citrus are attacked by pest mites such as the citrus rust mite Phyllocoptruta oleivora (Ashmead (Acari: Eriophyidae and the spider mite Tetranychus mexicanus (McGregor (Acari: Tetranychidae. However, little is known on citrus rootstocks influencing pest mites. We aimed to evaluate the influence of rootstocks on population densities of pest mites on the sweet oranges 'Pera CNPMF D-6' and 'Valencia Tuxpan' throughout time. Adults of both mite species were monthly counted during 19 months from June 2011 to February 2013. Rootstocks influenced the populations of pest mites, since lower densities of P. oleivora were found on 'Pera CNPMF D-6' sweet orange grafted on the hybrid TSKC × CTTR - 002 and on 'Swingle' citrumelo in comparison with the hybrid LVK × LCR - 010, 'Red' rough lime and 'Santa Cruz' rangpur lime as rootstocks. Similarly, lower densities of T. mexicanus were found on 'Valencia Tuxpan' sweet orange grafted on the hybrid HTR-051 in comparison to 'Indio' citrandarin, 'Sunki Tropical' mandarin and LVK × LCR - 010 as rootstocks. We concluded that densities of the mites P. oleivora and T. mexicanus on the sweet oranges 'Pera CNPMF D-6' and 'Valencia Tuxpan' were affected in some periods of the year by some rootstocks, suggesting influence of some genotypes on these pests.

  1. Health effects of predatory beneficial mites and wasps in greenhouses

    DEFF Research Database (Denmark)

    Bælum, Jesper; Enkegaard, Annie; Doekes, Gert

    2007-01-01

    A three-year study of 579 greenhouse workers in 31 firms investigated the effect of four different beneficial arthropods. It was shown that the thrips mite Amblyseeius cucumeris and the spider mite predator Phytoseiulus persimilis may cause allergy measured by blood tests as well as eye and nose...

  2. IPM potentials of microbial pathogens and diseases of mites

    NARCIS (Netherlands)

    van der Geest, L.P.S.; Ciancio, A.; Mukerji, K.G.

    2010-01-01

    An overview is given of diseases in mites, caused by infectious microorganisms. Many pathogens play an important role in the regulation of natural populations of mite populations and are for this reason subject of research on the feasibility to develop such pathogens to biological control agents.

  3. Epidemiological study of small ruminant mange mites in three agro ...

    African Journals Online (AJOL)

    P=0.79) of the host animals not affected the prevalence of mange mite (There was higher infestation of ... Though, mange mites in small ruminants are prevalent in Southern nation nationalities .... Summery of the coordinated project on development of feed ... In: Gray, G., Vilenberg, G., parasitological research in Africa, Nai-.

  4. Increased tolerance and resistance to virus infections: a possible factor in the survival of Varroa destructor-resistant honey bees (Apis mellifera.

    Directory of Open Access Journals (Sweden)

    Barbara Locke

    Full Text Available The honey bee ectoparasitic mite, Varroa destructor, has a world-wide distribution and inflicts more damage than all other known apicultural diseases. However, Varroa-induced colony mortality is more accurately a result of secondary virus infections vectored by the mite. This means that honey bee resistance to Varroa may include resistance or tolerance to virus infections. The aim of this study was to see if this is the case for a unique population of mite-resistant (MR European honey bees on the island of Gotland, Sweden. This population has survived uncontrolled mite infestation for over a decade, developing specific mite-related resistance traits to do so. Using RT-qPCR techniques, we monitored late season virus infections, Varroa mite infestation and honey bee colony population dynamics in the Gotland MR population and compared this to mite-susceptible (MS colonies in a close by apiary. From summer to autumn the deformed wing virus (DWV titres increased similarly between the MR and MS populations, while the black queen cell virus (BQCV and sacbrood virus (SBV titres decreased substantially in the MR population compared to the MS population by several orders of magnitude. The MR colonies all survived the following winter with high mite infestation, high DWV infection, small colony size and low proportions of autumn brood, while the MS colonies all perished. Possible explanations for these changes in virus titres and their relevance to Varroa resistance and colony winter survival are discussed.

  5. Increased tolerance and resistance to virus infections: a possible factor in the survival of Varroa destructor-resistant honey bees (Apis mellifera).

    Science.gov (United States)

    Locke, Barbara; Forsgren, Eva; de Miranda, Joachim R

    2014-01-01

    The honey bee ectoparasitic mite, Varroa destructor, has a world-wide distribution and inflicts more damage than all other known apicultural diseases. However, Varroa-induced colony mortality is more accurately a result of secondary virus infections vectored by the mite. This means that honey bee resistance to Varroa may include resistance or tolerance to virus infections. The aim of this study was to see if this is the case for a unique population of mite-resistant (MR) European honey bees on the island of Gotland, Sweden. This population has survived uncontrolled mite infestation for over a decade, developing specific mite-related resistance traits to do so. Using RT-qPCR techniques, we monitored late season virus infections, Varroa mite infestation and honey bee colony population dynamics in the Gotland MR population and compared this to mite-susceptible (MS) colonies in a close by apiary. From summer to autumn the deformed wing virus (DWV) titres increased similarly between the MR and MS populations, while the black queen cell virus (BQCV) and sacbrood virus (SBV) titres decreased substantially in the MR population compared to the MS population by several orders of magnitude. The MR colonies all survived the following winter with high mite infestation, high DWV infection, small colony size and low proportions of autumn brood, while the MS colonies all perished. Possible explanations for these changes in virus titres and their relevance to Varroa resistance and colony winter survival are discussed.

  6. The Effect of High-Intensity Interval Cycling Sprints Subsequent to Arm-Curl Exercise on Upper-Body Muscle Strength and Hypertrophy.

    Science.gov (United States)

    Kikuchi, Naoki; Yoshida, Shou; Okuyama, Mizuki; Nakazato, Koichi

    2016-08-01

    Kikuchi, N, Yoshida, S, Okuyama, M, and Nakazato, K. The effect of high-intensity interval cycling sprints subsequent to arm-curl exercise on upper-body muscle strength and hypertrophy. J Strength Cond Res 30(8): 2318-2323, 2016-The purpose of this study was to examine whether lower limb sprint interval training (SIT) after arm resistance training (RT) influences training response of arm muscle strength and hypertrophy. Twenty men participated in this study. We divided subjects into RT group (n = 6) and concurrent training group (CT, n = 6). The RT program was designed to induce muscular hypertrophy (3 sets × 10 repetitions [reps] at 80% 1 repetition maximum [1RM] of arm-curl exercise) and was performed in an 8-week training schedule performed 3 times per week on nonconsecutive days. Subjects assigned to the CT group performed identical protocols as strength training and modified SIT (4 sets of 30-s maximal effort, separated in 4 m 30-s rest intervals) on the same day. Pretest and posttest maximal oxygen consumption (V[Combining Dot Above]O2max), muscle cross-sectional area (CSA), and 1RM were measured. Significant increase in V[Combining Dot Above]O2max from pretest to posttest was observed in the CT group (p = 0.010, effect size [ES] = 1.84) but not in the RT group (p = 0.559, ES = 0.35). Significant increase in CSA from pretest to posttest was observed in the RT group (p = 0.030, ES = 1.49) but not in the CT group (p = 0.110, ES = 1.01). Significant increase in 1RM from pretest to posttest was observed in the RT group (p = 0.021, ES = 1.57) but not in the CT group (p = 0.065, ES = 1.19). In conclusion, our data indicate that concurrent lower limb SIT interferes with arm muscle hypertrophy and strength.

  7. Plant MITEs: Useful Tools for Plant Genetics and Genomics

    Institute of Scientific and Technical Information of China (English)

    Ying Feng

    2003-01-01

    MITEs (Miniature inverted-repeat transposable elements) are reminiscence of non-autonomous DNA (class Ⅱ) elements, which are distinguished from other transpos-able elements by their small size, short terminal inverted repeats (TIRs), high copynumbers, genic preference, and DNA sequence identity among family members. Al-though MITEs were first discovered in plants and still actively reshaping genomes,they have been isolated from a wide range of eukaryotic organisms. MITEs canbe divided into Tourist-like, Stowaway-like, and pogo-like groups, according tosimilarities of their TIRs and TSDs (target site duplications). In despite of sev-eral models to explain the origin and amplification of MITEs, their mechanisms oftransposition and accumulation in eukaryotic genomes remain poorly understoodowing to insufficient experimental data. The unique properties of MITEs have beenexploited as useful genetic tools for plant genome analysis. Utilization of MITEsas effective and informative genomic markers and potential application of MITEsin plants systematic, phylogenetic, and genetic studies are discussed.

  8. Behavior of the Linea Alba During a Curl-up Task in Diastasis Rectus Abdominis: An Observational Study.

    Science.gov (United States)

    Lee, Diane; Hodges, Paul W

    2016-07-01

    Study Design Cross-sectional repeated measures. Background Rehabilitation of diastasis rectus abdominis (DRA) generally aims to reduce the inter-rectus distance (IRD). We tested the hypothesis that activation of the transversus abdominis (TrA) before a curl-up would reduce IRD narrowing, with less linea alba (LA) distortion/deformation, which may allow better force transfer between sides of the abdominal wall. Objectives This study investigated behavior of the LA and IRD during curl-ups performed naturally and with preactivation of the TrA. Methods Curl-ups were performed by 26 women with DRA and 17 healthy control participants using a natural strategy (automatic curl-up) and with TrA preactivation (TrA curl-up). Ultrasound images were recorded at 2 points above the umbilicus (U point and UX point). Ultrasound measures of IRD and a novel measure of LA distortion (distortion index: average deviation of the LA from the shortest path between the recti) were compared between 3 tasks (rest, automatic curl-up, TrA curl-up), between groups, and between measurement points (analysis of variance). Results Automatic curl-up by women with DRA narrowed the IRD from resting values (mean U-point between-task difference, -1.19 cm; 95% confidence interval [CI]: -1.45, -0.93; PUX-point between-task difference, -0.51 cm; 95% CI: -0.69, -0.34; PUX-point between-task difference, 0.025; 95% CI: 0.004, 0.045; P = .02). Although TrA curl-up induced no narrowing or less IRD narrowing than automatic curl-up (mean U-point difference between TrA curl-up versus rest, -0.56 cm; 95% CI: -0.82, -0.31; PUX-point between-task difference, 0.02 cm; 95% CI: -0.22, 0.19; P = .86), LA distortion was less (mean U-point between-task difference, -0.025; 95% CI: -0.037, -0.012; PUX-point between-task difference, -0.021; 95% CI: -0.038, -0.005; P = .01). Inter-rectus distance and the distortion index did not change from rest or differ between tasks for controls (P≥.55). Conclusion Narrowing of the IRD

  9. Curl flux, coherence, and population landscape of molecular systems: Nonequilibrium quantum steady state, energy (charge) transport, and thermodynamics

    CERN Document Server

    Zhang, Zhedong

    2015-01-01

    We established a theoretical framework in terms of the curl flux, population landscape, and coherence for non-equilibrium quantum systems at steady state, through exploring the energy and charge transport in molecular processes. The curl quantum flux plays the key role in determining transport properties and the system reaches equilibrium when flux vanishes. The novel curl quantum flux reflects the degree of non-equilibriumness and the time-irreversibility. We found an analytical expression for the quantum flux and its relationship to the environmental pumping (non-equilibriumness quantified by the voltage away from the equilibrium) and the quantum tunneling. Furthermore, we investigated another quantum signature, the coherence, quantitatively measured by the non-zero off diagonal element of the density matrix. Besides the environment-assistance which can give dramatic enhancement of coherence and quantum flux with high voltage at a fixed tunneling strength, the quantum flux is promoted by the coherence in th...

  10. Nasal mites of Tyrannidae (Aves in Brazil

    Directory of Open Access Journals (Sweden)

    MM. Mendes

    Full Text Available A total of 81 Tyraniidae birds were examined, 80 Pitangus sulphuratus (Linnaeus, 1766 (Great kiscadee, and one Machetornis rixosa (Vieilot, 1819 (Cattle tyrant, for collection of nasal mites, which were identified as Ptilonyssus spinosus (Brooks & Strandtmann, 1960 and Sternostoma longisetosae (Hyland, 1961 (Rhinonyssidae. This finding characterises the first report of P. spinosus and S. longisetosae in P. sulphuratus, and the first record of P. spinosus in M. rixosa, and expands the geographic distribution of these species. It is the first occurrence of S. longisetosae in the Neotropics, and the first citation of P. spinosus in the state of Rio Grande do Sul, Brazil.

  11. Democracia: límites y perspectivas

    OpenAIRE

    Bolívar Espinoza, Gardy Augusto; Castro Herrera, Guillermo; Cuéllar Saavedra, Óscar; Dewey, John; Editorial, Equipo; Fernández Buey, Francisco; Fernández Nadal, Estela; Guevara Avila, Jean Paul; Gumucio, Rafael; Habermas, Jürgen; Hardin, Garrett; Hinkelammert, Franz; Oquendo, Ángel; Pizarro, Roberto; Portales, Felipe

    2005-01-01

    Para quienes hemos vivido largos períodos dictatoriales habiendo tenido previamente la experiencia de conocer los horizontes que abre y a la vez sus límites, la democracia es como el aire que respiramos: mientras lo tenemos no nos damos cuenta de su valor y de su necesidad, si nos falta hay que ver cómo nos duele. Sin embargo la democracia no es ni fácil ni placentera a veces; como lo señalara Estanislao Zuleta, “la democracia implica la aceptación de un cierto grado de angustia”. No es una p...

  12. Morphological and anatomical characters of apple leaves associated with cultivar susceptibility to spider mite infestation

    Directory of Open Access Journals (Sweden)

    Wojciech Warabieda

    2013-12-01

    Full Text Available Morphological and anatomical chaIacters of apple leaves associated with cultivar susceptibility to two-spotted spider mite (Tetranychus urticae (Koch. infestation were investigated. The following six apple cultivars were selected for the research: Close, Lobo ( suceptible and Katja, Piros, Jester, Maivit (more resistant to mites infestation. The cultivars of a relatively lower susceptibility, (except Marvit were provided with a poorer pubescence on abaxial epidermis of foliage leaf than those susceptible. There was no strict correlation between stomata number per unit of the leaf surface and the susceptibility to T.urticae infestation. A tight cell arrangement in the spongy mesophyll was particularly characteristic for cv Marvit, whereas in the leaves of cvs Close and Lobo this tissue was definitely loose. It seems that loose spongy mesophyll structure may facilitate feeding of mites.The results regarding the analysis of the lower (abaxial epidermis of the leaves seem to suggest that the layout and thickness of cuticle, rather than the epidermal thickness itself could be a factor determining the susceptibility of apple cultivars to T.urcitae.

  13. House dust mites and their allergens at selected locations in the homes of house dust mite-allergic patients

    DEFF Research Database (Denmark)

    Sidenius, K E; Hallas, T E; Brygge, T

    2002-01-01

    Knowledge of the occurrence of house dust mites (HDM) and their allergens in domestic locations is important when planning intervention.......Knowledge of the occurrence of house dust mites (HDM) and their allergens in domestic locations is important when planning intervention....

  14. Mattress encasings and mite allergen levels in the Prevention and Incidence of Asthma and Mite Allergy study

    NARCIS (Netherlands)

    van Strien, RT; Koopman, LP; Kerkhof, M; Oldenwening, M; de Jongste, JC; Gerritsen, J; Neijens, HJ; Aalberse, RC; Smit, HA; Brunekreef, B

    2003-01-01

    Background Reduction of allergen exposure from birth may reduce sensitization and subsequent allergic disease. Objective To measure the influence of mite allergen-impermeable mattress encasings and cotton placebo encasings on the amount of dust and mite allergen in beds. Methods A total of 810 child

  15. Laboratory tests for controlling poultry red mites (Dermanyssus gallinae) with predatory mites in small 'laying hen' cages

    NARCIS (Netherlands)

    Lesna, Izabela; Sabelis, Maurice W.; van Niekerk, Thea G. C. M.; Komdeur, Jan

    2012-01-01

    To assess their potential to control poultry red mites (Dermanyssus gallinae), we tested selected predaceous mites (Androlaelaps casalis and Stratiolaelaps scimitus) that occur naturally in wild bird nests or sometimes spontaneously invade poultry houses. This was done under laboratory conditions in

  16. Mattress encasings and mite allergen levels in the Prevention and Incidence of Asthma and Mite Allergy study

    NARCIS (Netherlands)

    van Strien, RT; Koopman, LP; Kerkhof, M; Oldenwening, M; de Jongste, JC; Gerritsen, J; Neijens, HJ; Aalberse, RC; Smit, HA; Brunekreef, B

    2003-01-01

    Background Reduction of allergen exposure from birth may reduce sensitization and subsequent allergic disease. Objective To measure the influence of mite allergen-impermeable mattress encasings and cotton placebo encasings on the amount of dust and mite allergen in beds. Methods A total of 810 child

  17. Laboratory tests for controlling poultry red mites (Dermanyssus gallinae) with predatory mites in small 'laying hen' cages

    NARCIS (Netherlands)

    Lesna, Izabela; Sabelis, Maurice W.; van Niekerk, Thea G. C. M.; Komdeur, Jan

    2012-01-01

    To assess their potential to control poultry red mites (Dermanyssus gallinae), we tested selected predaceous mites (Androlaelaps casalis and Stratiolaelaps scimitus) that occur naturally in wild bird nests or sometimes spontaneously invade poultry houses. This was done under laboratory conditions in

  18. Laboratory tests for controlling poultry red mites (Dermanyssus gallinae) with predatory mites in small ‘laying hen’ cages

    NARCIS (Netherlands)

    Lesna, I.; Sabelis, M.W.; van Niekerk, T.G.C.M.; Komdeur, J.

    2012-01-01

    o assess their potential to control poultry red mites (Dermanyssus gallinae), we tested selected predaceous mites (Androlaelaps casalis and Stratiolaelaps scimitus) that occur naturally in wild bird nests or sometimes spontaneously invade poultry houses. This was done under laboratory conditions in

  19. Laboratory tests for controlling poultry red mites (Dermanyssus gallinae) with predatory mites in small ‘laying hen’ cages

    NARCIS (Netherlands)

    Lesna, I.; Sabelis, M.W.; Niekerk, van T.G.C.M.; Komdeur, J.

    2012-01-01

    To assess their potential to control poultry red mites (Dermanyssus gallinae), we tested selected predaceous mites (Androlaelaps casalis and Stratiolaelaps scimitus) that occur naturally in wild bird nests or sometimes spontaneously invade poultry houses. This was done under laboratory conditions in

  20. Application of Two-spotted Spider Mite Tetranychus urticae for Plant-pest Interaction Studies

    Science.gov (United States)

    Negrave, Tara; Van Leeuwen, Thomas; Grbic, Vojislava; Grbic, Miodrag

    2014-01-01

    The two-spotted spider mite, Tetranychus urticae, is a ubiquitous polyphagous arthropod herbivore that feeds on a remarkably broad array of species, with more than 150 of economic value. It is a major pest of greenhouse crops, especially in Solanaceae and Cucurbitaceae (e.g., tomatoes, eggplants, peppers, cucumbers, zucchini) and greenhouse ornamentals (e.g., roses, chrysanthemum, carnations), annual field crops (such as maize, cotton, soybean, and sugar beet), and in perennial cultures (alfalfa, strawberries, grapes, citruses, and plums)1,2. In addition to the extreme polyphagy that makes it an important agricultural pest, T. urticae has a tendency to develop resistance to a wide array of insecticides and acaricides that are used for its control3-7. T. urticae is an excellent experimental organism, as it has a rapid life cycle (7 days at 27 °C) and can be easily maintained at high density in the laboratory. Methods to assay gene expression (including in situ hybridization and antibody staining) and to inactivate expression of spider mite endogenous genes using RNA interference have been developed8-10. Recently, the whole genome sequence of T. urticae has been reported, creating an opportunity to develop this pest herbivore as a model organism with equivalent genomic resources that already exist in some of its host plants (Arabidopsis thaliana and the tomato Solanum lycopersicum)11. Together, these model organisms could provide insights into molecular bases of plant-pest interactions. Here, an efficient method for quick and easy collection of a large number of adult female mites, their application on an experimental plant host, and the assessment of the plant damage due to spider mite feeding are described. The presented protocol enables fast and efficient collection of hundreds of individuals at any developmental stage (eggs, larvae, nymphs, adult males, and females) that can be used for subsequent experimental application. PMID:25046103

  1. Wave control through soft microstructural curling: bandgap shifting, reconfigurable anisotropy and switchable chirality

    Science.gov (United States)

    Celli, Paolo; Gonella, Stefano; Tajeddini, Vahid; Muliana, Anastasia; Ahmed, Saad; Ounaies, Zoubeida

    2017-03-01

    In this work, we discuss and numerically validate a strategy to attain reversible macroscopic changes in the wave propagation characteristics of cellular metamaterials with soft microstructures. The proposed cellular architecture is characterized by unit cells featuring auxiliary populations of symmetrically-distributed smart cantilevers stemming from the nodal locations. Through an external stimulus (the application of an electric field), we induce extreme, localized, reversible curling deformation of the cantilevers—a shape modification which does not affect the overall shape, stiffness and load bearing capability of the structure. By carefully engineering the spatial pattern of straight (non activated) and curled (activated) cantilevers, we can induce several profound modifications of the phononic characteristics of the structure: generation and/or shifting of total and partial bandgaps, cell symmetry relaxation (which implies reconfigurable wave beaming), and chirality switching. While in this work we discuss the specific case of composite cantilevers with a PDMS core and active layers of electrostrictive terpolymer P(VDF-TrFE-CTFE), the strategy can be extended to other smart materials (such as dielectric elastomers or shape-memory polymers).

  2. Genetic diversity, host range, and distribution of tomato yellow leaf curl virus in Iran.

    Science.gov (United States)

    Shirazi, M; Mozafari, J; Rakhshandehroo, F; Shams-Bakhsh, M

    2014-01-01

    Tomato yellow leaf curl virus (TYLCV) is considered one of the most important tomato pathogens in tropical and subtropical regions including Iran. During the years 2007 to 2009, a total number of 510 symptomatic and asymptomatic vegetable, ornamental and weed samples were collected from fields and greenhouses in ten provinces of Iran. Symptoms included stunting, yellowing, leaf curl and flower senescence. PCR with specific primers showed TYLCV infection in 184 samples (36%) such as cucumber, pepper, tomato and several weeds from seven provinces. Based on the geographical origin, host range and symptoms, twenty three representative isolates were selected for phylogenetic analysis. An amplicon with a size about 608 base pair (bp) comprising partial sequence of the coat (CP) and movement protein (MP) coding regions of the viral genome was sequenced and compared with the corresponding selected sequences available in GenBank for Iran and worldwide. Phylogenetic analyses on the basis of the nucleotide sequences indicated two geographically separated clades. Isolates collected from Hormozgan, Khuzestan and Kerman provinces were grouped together with other Iranian isolates including TYLCV-Ir2, TYLCV-Kahnooj, and an isolate from Oman. It was also revealed that isolates collected from Boushehr, Fars, Tehran, and Isfahan placed close to the Iranian isolate TYLCV-Abadeh and isolates from Israel and Egypt. No correlation was found between the genetic variation and the host species, but selected Iranian isolates were grouped on the basis of the geographical origins. Results of this study indicated a high genetic diversity among Iranian TYLCV isolates.

  3. Laboratory tests for controlling poultry red mites (Dermanyssus gallinae) with predatory mites in small 'laying hen' cages.

    Science.gov (United States)

    Lesna, Izabela; Sabelis, Maurice W; van Niekerk, Thea G C M; Komdeur, Jan

    2012-12-01

    To assess their potential to control poultry red mites (Dermanyssus gallinae), we tested selected predaceous mites (Androlaelaps casalis and Stratiolaelaps scimitus) that occur naturally in wild bird nests or sometimes spontaneously invade poultry houses. This was done under laboratory conditions in cages, each with 2-3 laying hens, initially 300 poultry red mites and later the release of 1,000 predators. These small-scale tests were designed to prevent mite escape from the cages and they were carried out in three replicates at each of three temperature regimes: 26, 30 (constant day and night) and 33-25 °C (day-night cycle). After 6 weeks total population sizes of poultry red mites and predatory mites were assessed. For the temperature regimes of 26 and 33/25 °C S. scimitus reduced the poultry red mite population relative to the control experiments by a factor 3 and 30, respectively, and A. casalis by a factor of 18 and 55, respectively. At 30 °C the predators had less effect on red mites, with a reduction of 1.3-fold for S. scimitus and 5.6-fold for A. casalis. This possibly reflected hen manure condition or an effect of other invertebrates in the hen feed. Poultry red mite control was not negatively affected by temperatures as high as 33 °C and was always better in trials with A. casalis than in those with S. scimitus. In none of the experiments predators managed to eradicate the population of poultry red mites. This may be due to a prey refuge effect since most predatory mites were found in and around the manure tray at the bottom of the cage, whereas most poultry red mites were found higher up in the cage (i.e. on the walls, the cover, the perch, the nest box and the food box). The efficacy of applying predatory mites in the poultry industry may be promoted by reducing this refuge effect, boosting predatory mite populations using alternative prey and prolonged predator release devices. Biocontrol success, however, will strongly depend on how the poultry is

  4. Radiographic inguinal curl may indicate paraspinal misplacement of percutaneously inserted central venous catheters: report of three cases

    Energy Technology Data Exchange (ETDEWEB)

    Chedid, Faris [Al Tawam Hospital, Department of Paediatrics, Al Ain, Abu Dhabi (United Arab Emirates); Abbas, Adil [Royal Children' s Hospital, Department of Clinical Haematology/Oncology, Brisbane (Australia); Morris, Lloyd [Women' s and Children' s Hospital, Department of Medical Imaging, Adelaide (Australia)

    2005-07-01

    Misplacement of percutaneously inserted central venous catheters (PCVCs) into the paraspinal venous plexus can result in devastating outcomes. Several cases have been reported in the literature together with an explanation of the mechanism. To describe three premature babies with their PCVCs inserted through the left saphenous vein that ended up in the lumbar spinal dural venous plexus. Plain radiographs obtained to check positions showed an unusual 360 curl of the PCVC in the left inguinal area. We believe that misplacement of the catheter into the paraspinal venous plexus could be diagnosed with great accuracy if such a curl is seen. (orig.)

  5. Decay of house-dust mite allergen Der f 1 at indoor climatic conditions

    DEFF Research Database (Denmark)

    Sidenius, Kirsten E; Hallas, Thorkil E; Stenderup, Jørgen;

    2002-01-01

    The decay of house-dust mite allergens is important for the outcome of avoidance measures for house-dust mite-allergic patients.......The decay of house-dust mite allergens is important for the outcome of avoidance measures for house-dust mite-allergic patients....

  6. Failure of the mite-pathogenic fungus Neozygites tanajoae and the predatory mite Neoseiulus idaeus to control a population of the cassava green mite, Mononychellus tanajoa.

    Science.gov (United States)

    Elliot, Simon L; de Moraes, Gilberto J; Mumford, John D

    2008-12-01

    Monitoring of a population of the phytophagous cassava green mite, Mononychellus tanajoa (Bondar), and its natural enemies was undertaken in central Bahia, Brazil, in mid-1996. In spite of the presence of extremely high densities of the predatory phytoseiid mite Neoseiulus idaeus Denmark & Muma, the phytophagous mite population reached such high densities itself that there was total overexploitation of the cassava plants, leading to total leaf loss. Meanwhile, the mite-pathogenic fungus Neozygites tanajoae Delalibera, Humber & Hajek did not affect the M. tanajoa population in its growth phase as there was no inoculum present, even though we predict from a simple regression model that there was the potential for epizootics at that time. Soon after the M. tanajoa population crashed due to defoliation, there could have been an epizootic but there were simply no mite hosts to infect. These data demonstrate the ineffectiveness of one natural enemy (the predator) in terms of prey population regulation and demonstrate the importance of timing in the possible effectiveness of the other (the pathogen). For the pathogen, this probably explains its sporadic effect on host populations as previously reported. We conclude that the fungus is likely to be most useful as an adjunct to biological control with predatory mites other than N. idaeus.

  7. Tomato yellow leaf curl viruses: ménage à trois between the virus complex, the plant and the whitefly vector.

    Science.gov (United States)

    Díaz-Pendón, Juan Antonio; Cañizares, M Carmen; Moriones, Enrique; Bejarano, Eduardo R; Czosnek, Henryk; Navas-Castillo, Jesús

    2010-07-01

    Tomato yellow leaf curl disease (TYLCD) is one of the most devastating viral diseases affecting tomato crops in tropical, subtropical and temperate regions of the world. Here, we focus on the interactions through recombination between the different begomovirus species causing TYLCD, provide an overview of the interactions with the cellular genes involved in viral replication, and highlight recent progress on the relationships between these viruses and their vector, the whitefly Bemisia tabaci. The tomato yellow leaf curl virus-like viruses (TYLCVs) are a complex of begomoviruses (family Geminiviridae, genus Begomovirus) including 10 accepted species: Tomato yellow leaf curl Axarquia virus (TYLCAxV), Tomato yellow leaf curl China virus (TYLCCNV), Tomato yellow leaf curl Guangdong virus (TYLCGuV), Tomato yellow leaf curl Indonesia virus (TYLCIDV), Tomato yellow leaf curl Kanchanaburi virus (TYLVKaV), Tomato yellow leaf curl Malaga virus (TYLCMalV), Tomato yellow leaf curl Mali virus (TYLCMLV), Tomato yellow leaf curl Sardinia virus (TYLCSV), Tomato yellow leaf curl Thailand virus (TYLCTHV), Tomato yellow leaf curl Vietnam virus (TYLCVNV) and Tomato yellow leaf curl virus(TYLCV). We follow the species demarcation criteria of the International Committee on Taxonomy of Viruses (ICTV), the most important of which is an 89% nucleotide identity threshold between full-length DNA-A component nucleotide sequences for begomovirus species. Strains of a species are defined by a 93% nucleotide identity threshold. The primary host of TYLCVs is tomato (Solanum lycopersicum), but they can also naturally infect other crops [common bean (Phaseolus vulgaris), sweet pepper (Capsicum annuum), chilli pepper (C. chinense) and tobacco (Nicotiana tabacum)], a number of ornamentals [petunia (Petuniaxhybrida) and lisianthus (Eustoma grandiflora)], as well as common weeds (Solanum nigrum and Datura stramonium). TYLCVs also infect the experimental host Nicotiana benthamiana. Infected tomato

  8. Bartonella-like bacteria carried by domestic mite species.

    Science.gov (United States)

    Kopecký, Jan; Nesvorná, Marta; Hubert, Jan

    2014-01-01

    Bacteria of the genus Bartonella are carried by haematophagous mites, ticks, fleas and flies, and attack the erythrocytes of mammals. Here we describe a Bartonella-like clade, a distinct group related to Bartonellaceae, in stored-product mites (Acari: Astigmata) and a predatory mite Cheyletus eruditus (Acari: Prostigmata) based on the analysis of cloned 16S rRNA gene sequences. By using the clade-specific primers, closely related Bartonella-like 16S rRNA sequences were amplified from both laboratory colonies and field strains of three synanthropic mite species (Acarus siro, Lepidoglyphus destructor and Tyrophagus putrescentiae) and a predatory mite. Altogether, sequences of Bartonella-like bacteria were found in 11 strains, but were not detected in Dermatophagoides farinae and D. pteronyssinus and two strains of L. destructor. All obtained sequences formed a separate cluster branching as a sister group to Bartonellaceae and related to other separate clusters comprising uncultured bacterial clones from human skin and hemipteran insects (Nysius plebeius and Nysius sp.). The classification of sequences into operational taxonomic units (OTUs) showed a difference between A. siro and T. putrescentiae suggesting that the Bartonella-like bacteria are different in these two mite species. However, species specific sequences in separate OTUs were observed also for C. eruditus. Possible symbiotic interactions between Bartonella-like bacteria and their mite hosts are discussed.

  9. Plant MITEs: useful tools for plant genetics and genomics.

    Science.gov (United States)

    Feng, Ying

    2003-05-01

    MITEs (Miniature inverted-repeat transposable elements) are reminiscence of non-autonomous DNA (class II) elements, which are distinguished from other transposable elements by their small size, short terminal inverted repeats (TIRs), high copy numbers, genic preference, and DNA sequence identity among family members. Although MITEs were first discovered in plants and still actively reshaping genomes, they have been isolated from a wide range of eukaryotic organisms. MITEs can be divided into Tourist-like, Stowaway-like, and pogo-like groups, according to similarities of their TIRs and TSDs (target site duplications). In despite of several models to explain the origin and amplification of MITEs, their mechanisms of transposition and accumulation in eukaryotic genomes remain poorly understood owing to insufficient experimental data. The unique properties of MITEs have been exploited as useful genetic tools for plant genome analysis. Utilization of MITEs as effective and informative genomic markers and potential application of MITEs in plants systematic, phylogenetic, and genetic studies are discussed.

  10. Pheromonal Communication in the European House Dust Mite, Dermatophagoides pteronyssinus

    Directory of Open Access Journals (Sweden)

    Johannes L.M. Steidle

    2014-08-01

    Full Text Available Despite the sanitary importance of the European house dust mite Dermatophagoides pteronyssinus (Trouessart, 1897, the pheromonal communication in this species has not been sufficiently studied. Headspace analysis using solid phase micro extraction (SPME revealed that nerol, neryl formate, pentadecane, (6Z,9Z-6,9-heptadecadiene, and (Z-8-heptadecene are released by both sexes whereas neryl propionate was released by males only. Tritonymphs did not produce any detectable volatiles. In olfactometer experiments, pentadecane and neryl propionate were attractive to both sexes as well as to tritonymphs. (Z-8-heptadecene was only attractive to male mites. Therefore it is discussed that pentadecane and neryl propionate are aggregation pheromones and (Z-8-heptadecene is a sexual pheromone of the European house dust mite D. pteronyssinus. To study the potential use of pheromones in dust mite control, long-range olfactometer experiments were conducted showing that mites can be attracted to neryl propionate over distances of at least 50 cm. This indicates that mite pheromones might be useable to monitor the presence or absence of mites in the context of control strategies.

  11. Coincidental intraguild predation by caterpillars on spider mites.

    Science.gov (United States)

    Shirotsuka, Kanako; Yano, Shuichi

    2012-01-29

    Intraguild predation (IGP) is defined as the killing and eating of prey species by a predator that also can utilize the resources of the prey. It is mainly reported among carnivores that share common herbivorous prey. However, a large chewing herbivore could prey upon sedentary and/or micro herbivores in addition to utilizing a host plant. To investigate such coincidental IGP, we observed the behavioral responses of the polyphagous mite Tetranychus kanzawai Kishida (Acari: Tetranychidae) when its host plant Cayratia japonica (Thunb.) Gagnep. (Vitaceae) was attacked by hornworms, Theretra japonica Boisduval (Sphingidae) and T. oldenlandiae Fabricius (Sphingidae). We also examined an interaction between the oligophagous mite Panonychus citri McGregor (Acari: Tetranychidae) and caterpillars of the swallowtail Papilio xuthus L. (Papilionidae) that share citrus plants as their main food source. Although all T. kanzawai and some active stage P. citri tried to escape from the coincidental IGP, some were consumed together with eggs, quiescent mites, and host plant leaves, suggesting that coincidental IGP occurs on spider mites in the wild. Moreover, neither hornworms nor swallowtail caterpillars distinguished between spider mite-infested and uninfested leaves, suggesting that the mite-infested leaves do not discourage caterpillar feeding. The reasons that the mites have no effective defense against coincidental IGP other than escaping are discussed.

  12. The use of soil mites in ecotoxicology: a review.

    Science.gov (United States)

    Huguier, Pierre; Manier, Nicolas; Owojori, Olugbenga John; Bauda, Pascale; Pandard, Pascal; Römbke, Jörg

    2015-01-01

    Mites, and especially soil-inhabiting ones, have been less studied than the other invertebrates used in bio-assays for the assessment of soil quality and the hazards of chemicals, although these organisms are included in the regulatory assessment scheme of pesticides. The recent advances in the development of test methods for soil mites groups have provided more information on their sensitivities towards chemicals, which needs to be presented for a more robust assessment of the current trends in soil mite ecotoxicology. Moreover, interestingly mite is the only taxa for which test methods were developed and standardized on predatory organisms. This review summarizes the different protocols for the assessment of chemicals using soil-inhabiting mites, including laboratory, semi-field and field studies. Among the data found in the literature, most of the chemicals assessed with mites were pesticides, while a few environmental samples were assessed with these organisms. Their sensitivities towards chemicals were then compared and discussed regarding other soil invertebrates. Finally, we conclude on the usefulness of soil mites in ecotoxicology, and provide future research trail in this area.

  13. Do Demodex mites play a role in pterygium development?

    Science.gov (United States)

    Tarkowski, Witold; Moneta-Wielgoś, Joanna; Młocicki, Daniel

    2017-01-01

    Numerous reports point to Demodex mites as the aetiology of certain eye and skin conditions, hence it is highly probable that infestation with these mites may also play a role in the aetiology and pathogenesis of pterygium. Therefore here we present a hypothesis: whether the presence of Demodex mites in eyelash hair follicles significantly correlates with the presence of pterygia, which could point to a potential role of these mites in the development of such lesions. We present preliminary data for supporting this hypothesis. These results were collected from a group of 69 subjects, including 39 with pterygium. Subjects were studied for the presence of Demodex folliculorum and/or D. brevis within eyelash follicles. The sample was defined as positive if at least one parasite, larva or egg were present. Preliminary statistical analyses were performed, and indicated a significant relationship between Demodex mite infestation and the presence of pterygium (pDemodex infestation formed a dominant group. The proportion of subjects with both pterygia and Demodex presence is high at 93.33%, while the proportion of subjects without pterygia who have mites is low at 20.51%. Aforementioned results support our working hypothesis that infestation with Demodex mites may result in pterygium development and therefore patients diagnosed with pterygium should be assessed for the presence of Demodex to verify our preliminary results. In the present paper, we discuss potential influence of Demodex on conjunctiva and propose a hypothetical pathological mechanism linking the development of pterygia with demodicosis.

  14. The Effect of Antibiotics on Associated Bacterial Community of Stored Product Mites

    OpenAIRE

    2014-01-01

    Background Bacteria are associated with the gut, fat bodies and reproductive organs of stored product mites (Acari: Astigmata). The mites are pests due to the production of allergens. Addition of antibiotics to diets can help to characterize the association between mites and bacteria. Methodology and Principal Findings Ampicillin, neomycin and streptomycin were added to the diets of mites and the effects on mite population growth (Acarus siro, Lepidoglyphus destructor and Tyrophagus putrescen...

  15. Significance and control of the poultry red mite, Dermanyssus gallinae.

    Science.gov (United States)

    Sparagano, O A E; George, D R; Harrington, D W J; Giangaspero, A

    2014-01-01

    The poultry red mite, Dermanyssus gallinae, poses a significant threat to poultry production and hen health in many parts of the world. With D. gallinae increasingly suspected of being a disease vector, and reports indicating that attacks on alternative hosts, including humans, are becoming more common, the economic importance of this pest has increased greatly. As poultry production moves away from conventional cage systems in many parts of the world, D. gallinae is likely to become more abundant and difficult to control. Control remains dominated by the use of synthetic acaricides, although resistance and treatment failure are widely reported. Alternative control measures are emerging from research devoted to D. gallinae and its management. These alternative control measures are beginning to penetrate the market, although many remain at the precommercial stage. This review compiles the expanding body of research on D. gallinae and assesses options for its current and future control. We conclude that significant advances in D. gallinae control are most likely to come through an integrated approach adopting recent research into existing and novel control strategies; this is being combined with improved monitoring and modeling to better inform treatment interventions.

  16. New mite species associated with certain plant species from Guam

    Directory of Open Access Journals (Sweden)

    Gadi V.P. Reddy

    2011-04-01

    Full Text Available Several new mite species have been reported from certain plants from Guam. Most remarkably, the spider mite, Tetranychus marianae (Prostigmata: Tetranychidae and the predatory mite Phytoseius horridus (Mesostigmata: Phytoseiidae (Solanum melongena have been found on eggplant. The noneconomically important species of Brevipalpus californicus(Banks Prostigmata: Tenuipalpidae,Eupodes sp. (Acarina: Eupodidae and predator Cunaxa sp. (Prostigmata: Cunaxidae have been reported on guava (Psidium guajava L.. Also, the non-economically important species Brevipalpus californicus Prostigmata: Tenuipalpidae, Lepidoglyphus destructor (Astigmata: Glycyphagidae and a predator Amblyseius obtusus, species group Amblyseius near lentiginosus (Mesostigmata: Phytoseiidae, have been recorded on cycad (Cycas micronesica.

  17. Core Muscle Activation During Unstable Bicep Curl Using a Water-Filled Instability Training Tube.

    Science.gov (United States)

    Glass, Stephen C; Blanchette, Taylor W; Karwan, Lauren A; Pearson, Spencer S; OʼNeil, Allison P; Karlik, Dustin A

    2016-11-01

    Glass, SC, Blanchette, TW, Karwan, LA, Pearson, SS, O'Neil, AP, and Karlik, DA. Core muscle activation during unstable bicep curl using a water-filled instability training tube. J Strength Cond Res 30(11): 3212-3219, 2016-The purpose of this study was to assess compensatory muscle activation created during a bicep curl using a water-filled, unstable lifting tube. Ten men (age = 21 ± 1.6 years, height = 180.0 ± 3.3 cm, mass = 87.4 ± 15.0 kg) and 10 women (age = 19.6 ± 1.3 years, height = 161.4 ± 12.0 cm, mass = 61.2 ± 7.4 kg) completed bicep curls using an 11.4-kg tube partially filled with water during a 50% open-valve, 100% open, and control setting. Subjects completed 8 repetitions within each condition with integrated electromyographic signal (converted to percent maximal voluntary contraction) of the bicep, deltoid, rectus abdominus, and paraspinal muscles measured. Compensatory activation was determined using the natural log of coefficient of variation across concentric (CON) and eccentric (ECC) contractions. There were no differences between gender for any condition. Significant variability was seen across treatments for paraspinal muscles for CON and ECC at 50% (CON LnCV = 3.13 ± 0.56%, ECC LnCV = 3.34 ± 0.58%) and 100% (CON = 3.24 ± 0.34%, ECC = 3.46 ± 0.35%) compared with control (CON = 2.59 ± 0.47%, ECC = 2.80 ± 0.61%). Deltoid variability was greater at the 100% open setting (CON = 3.51 ± 0.53%, ECC = 3.56 ± 0.36%) compared with control (CON = 2.98 ± 0.35%, ECC = 2.97 ± 0.45%). The abdominal CON 100% showed variability (3.02 ± 0.47%) compared with control (2.65 ± 0.43%). Bicep activation remained unvaried. Compensatory activation of postural muscles contribute to postural stability. This device may be a useful tool for neuromuscular training leading to improved stability and control.

  18. Nod factor-induced root hair curling: continuous polar growth towards the point of nod factor application

    NARCIS (Netherlands)

    Esseling, J.J.; Lhuissier, F.G.P.; Emons, A.M.C.

    2003-01-01

    A critical step in establishing a successful nitrogen-fixing symbiosis between rhizobia and legume plants is the entrapment of the bacteria between root hair cell walls, usually in characteristic 180degrees to 360degrees curls, shepherd's crooks, which are formed by the host's root hairs. Purified b

  19. Tomato yellow leaf curl virus can be acquired and transmitted by Bemisia tabaci (Gennadius) from tomato fruits

    NARCIS (Netherlands)

    Delatte, H.; Dalmon, A.; Rist, D.; Soustrade, I.; Wuster, G.; Lett, J.M.; Goldbach, R.W.; Peterschmitt, M.; Reynaud, B.

    2003-01-01

    The whitefly Bemisia tabaci is an insect pest causing worldwide economic losses, especially as a vector of geminiviruses such as Tomato yellow leaf curl virus (TYLCV). Currently, imported and exported tomato fruit are not monitored for TYLCV infection because they are not considered to represent a

  20. Harm mechanism and method of prevention and cure of yellow leaf curl virus(TYLCV) in tomato%番茄黄化曲叶病毒的危害机理及防治方法

    Institute of Scientific and Technical Information of China (English)

    马妙芳

    2015-01-01

    通过对野生番茄的对比研究,发现并找到了番茄抗黄化曲叶病毒6个抗TYLCV的基因。分别是TY-1、TY-2、TY-3,TY-3a、TY-4、TY-5,这些抗TY病毒的基因都是从国外的材料中发现的。目前我国已经育成的抗TY病毒的番茄品种有1000多个。防治番茄黄化曲叶病毒主要措施;一是严把抗性鉴定关,主推抗性强的优良品种;二是加强田间管理,控制病毒传播;三是加强对中心病株的防治。%Through comparative study of wild tom ato, the six resistance gene of tomato yellow leaf curl virus (TYLCV)were found and they were TY-1、TY-2、TY-3,TY-3a、TY-4 and TY-5. These resistant genes were found in the material from abroad. At present our country had bred more than 1 000 tomato varieties with TY virus resistance.The main measures of prevention of tomato yellow leaf curl virus (TYLCV) were strengthening resistance identification, popularizing varieties of strong resistance, strengthening field management, controling the spread of the virus and strengthening the treatment of center infected plant.

  1. El programa del límite

    Directory of Open Access Journals (Sweden)

    Carlos Walker

    2011-07-01

    Full Text Available En el terreno estético, se afirma desde un comienzo, no hay revés del extremo. La experiencia del límite, su radicalidad, sólo se alcanza en contados lugares. Si bien se accede a dicha experiencia a través de los medios de la representación, no se trata aquí de una representación del extremo. El silencio, cercano, convoca a desplazar sus bordes, y exhibe así un movimiento que es concebido como estandarte de la producción estética. Las narraciones de lo extremo se inscriben en la estela del ar...

  2. Identification of a bi-directional promoter from Tomato yellow leaf curl China virus

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    A bi-directional promoter of Tomato yellow leaf curl China virus (TYLCCNV) was obtained with the total DNA from TYLCCNV isolate Y10 infected tobacco leaves as a template. Plant expression vectors were constructed by fusing the amplified DNA fragment with the gus gene and nopaline terminator in different orientations. The vectors containing promoter fragments were transferred into leaf cells and plant stems of Nicotiana benthamiana by Agrobacterium-mediated method. Transient expression results showed that both the complementary and virion-sense promoters could drive the gus gene to express, and the GUS activity of the complementary-sense promoter was stronger than that of the virion-sense. Co-expression of the vector containing βC1 gene of TYLCCNV DNAβ with the vector containing a bi-directional promoter revealed that the βC1 protein has no impact on expression of either the virion- or the complementarysense promoter.

  3. Parallel eigensolver for H(curl) problems using H1-auxiliary space AMG preconditioning

    Energy Technology Data Exchange (ETDEWEB)

    Kolev, T V; Vassilevski, P S

    2006-11-15

    This report describes an application of the recently developed H{sup 1}-auxiliary space preconditioner for H(curl) problems to the Maxwell eigenvalue problem. The auxiliary space method based on the new (HX) finite element space decomposition introduced in [7], was implemented in the hypre library, [10, 11] under the name AMS. The eigensolver considered in the present paper, referred to as the AME, is an extension of the AMS. It is based on the locally optimal block eigensolver LOBPCG [9] and the parallel AMG (algebraic multigrid) solver BoomerAMG [2] from the hypre library. AME is designed to compute a block of few minimal nonzero eigenvalues and eigenvectors, for general unstructured finite element discretizations utilizing the lowest order Nedelec elements. The main goal of the current report is to document the usage of AME and to illustrate its parallel scalability.

  4. Effect of Deformation Condition on Axial CompressivePrecision Forming Process of Tube with Curling Die

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The effect of the deformation condition on the axial compressive precision forming process of tube with curling die was investigated by using a rigid-plastic FEM. The results show that the forming accuracy depends mainly on geometric condition rρ/d0, little on tube material properties and friction condition; the relative gap Δ/2rρ of double-walled tubes obtained decreases with increasing rρ/d0, and there is a parameter k for a given t0/d0 or rρ/t0, when rρ,/d0>k, Δ/2rρ<1,otherwise Δ/2rρ>1.

  5. Seed Transmission of Tomato yellow leaf curl virus in White Soybean (Glycine max).

    Science.gov (United States)

    Kil, Eui-Joon; Park, Jungho; Choi, Hong-Soo; Kim, Chang-Seok; Lee, Sukchan

    2017-08-01

    Tomato yellow leaf curl virus (TYLCV) infection of the common bean (Phaseolus vulgaris) has been reported, but soybean (Glycine max) has not previously been identified as a TYLCV host. Five cultivars of white soybean were agro-inoculated using an infectious TYLCV clone. At 30 days post-inoculation, they showed infection rates of 25% to 100%. Typical TYLCV symptoms were not observed in any inoculated plants. To examine whether TYLCV was transmitted in soybean seeds, DNA was isolated from bundles of five randomly selected seeds from TYLCV-inoculated soybean plants and amplified with a TYLCV-specific primer set. With the exception of one bundle, all bundles of seeds were verified to be TYLCV-infected. Virus dissemination was also confirmed in three of the 14 bunches. Viral replication was also identified in seeds and seedlings. This is the first report demonstrating that soybean is a TYLCV host, and that TYLCV is a seed-transmissible virus in white soybean.

  6. Detection and molecular characterization of tomato yellow leaf curl virus naturally infecting Lycopersicon esculentum in Egypt.

    Science.gov (United States)

    Rabie, M; Ratti, C; Abdel Aleem, E; Fattouh, F

    2017-01-01

    Tomato yellow leaf curl virus (TYLCV) infections of tomato crops in Egypt were widely spread in 2014. Infected symptomatic tomato plants from different governorates were sampled. TYLCV strains Israel and Mild (TYLCV-IL, TYLCV-Mild) were identified by multiplex and real-time PCR. In addition, nucleotide sequence analysis of the V1 and V2 protein genes, revealed ten TYLCV Egyptian isolates (TYLCV from TY1 to 10). Phylogenetic analysis showed their high degree of relatedness with TYLCV-IL Jordan isolate (98%). Here we have showed the complete nucleotide sequence of the TYLCV Egyptian isolate TY10, sampled from El Beheira. A high degree of similarity to other previously reported Egyptian isolates and isolates from Jordan and Japan reflect the importance of phylogenetic analysis in monitoring virus genetic diversity and possibilities for divergence of more virulent strains or genotypes.

  7. A Novel Strain of Tomato Leaf Curl New Delhi Virus Has Spread to the Mediterranean Basin

    Directory of Open Access Journals (Sweden)

    Isabel M. Fortes

    2016-11-01

    Full Text Available Tomato leaf curl New Delhi virus (ToLCNDV is a whitefly-transmitted bipartite begomovirus (genus Begomovirus, family Geminiviridae that causes damage to multiple cultivated plant species mainly belonging to the Solanaceae and Cucurbitaceae families. ToLCNDV was limited to Asian countries until 2012, when it was first reported in Spain, causing severe epidemics in cucurbit crops. Here, we show that a genetically-uniform ToLCNDV population is present in Spain, compatible with a recent introduction. Analyses of ToLCNDV isolates reported from other parts of the world indicated that this virus has a highly heterogeneous population genetically with no evident geographical, plant host or year-based phylogenetic groups observed. Isolates emerging in Spain belong to a strain that seems to have evolved by recombination. Isolates of this strain seem adapted to infecting cucurbits, but poorly infect tomatoes.

  8. Simple and Accurate Analytical Solutions of the Electrostatically Actuated Curled Beam Problem

    KAUST Repository

    Younis, Mohammad I.

    2014-08-17

    We present analytical solutions of the electrostatically actuated initially deformed cantilever beam problem. We use a continuous Euler-Bernoulli beam model combined with a single-mode Galerkin approximation. We derive simple analytical expressions for two commonly observed deformed beams configurations: the curled and tilted configurations. The derived analytical formulas are validated by comparing their results to experimental data in the literature and numerical results of a multi-mode reduced order model. The derived expressions do not involve any complicated integrals or complex terms and can be conveniently used by designers for quick, yet accurate, estimations. The formulas are found to yield accurate results for most commonly encountered microbeams of initial tip deflections of few microns. For largely deformed beams, we found that these formulas yield less accurate results due to the limitations of the single-mode approximations they are based on. In such cases, multi-mode reduced order models need to be utilized.

  9. Arrhenotoky and oedipal mating in the northern fowl mite (Ornithonyssus sylviarum (Acari: Gamasida: Macronyssidae

    Directory of Open Access Journals (Sweden)

    McCulloch John B

    2012-12-01

    Full Text Available Abstract Background The northern fowl mite (NFM; Ornithonyssus sylviarum is a blood-feeding ectoparasite of birds and a major pest of poultry in the United States. Mite populations spread rapidly in commercial flocks, reach peak burdens of >70,000 mites per bird and have developed resistance to many pesticides. Despite decades as a pest in the United States, the reproductive biology of NFM remains unclear. Based on karyotypes, the NFM has haplodiploid sex determination, which suggests unmated females could produce male offspring (arrhenotoky. Thus, unmated females could disseminate to a new host and initiate an infestation by producing and mating with sons (oedipal mating. Methods We used small capsules to isolate and recover NFM on host chickens. Mites in capsules could blood feed, develop and reproduce, but could not contact other mites. Individual larvae were matured in isolation to produce known, unmated females. We evaluated reproduction of (I previously mated females (i in isolation, or (ii paired with a male, and (II unmated (virgin females in isolation. In each treatment we recorded the number and sexes of offspring produced over time. Results Mated NFM produced female and male offspring in isolation, or when paired with a male. When paired with a male, females produced a female-biased sex ratio of the offspring (F:M ratio ~5:1. Unmated, female NFM produced exclusively male offspring when in isolation. When paired with their sons that had developed to maturity, the "virgin" females were able to mate and subsequently produce female offspring. Conclusions This study found that females with immediate access to sperm produced mostly female offspring. Virgin female NFM initially produced only male offspring and subsequently used oedipal mating to produce female offspring. Using this reproductive system NFM could successfully colonize new hosts as immature, or unmated females. The strong female-biased sex ratio of NFM populations suggests a

  10. High resolution genetic mapping uncovers chitin synthase-1 as the target-site of the structurally diverse mite growth inhibitors clofentezine, hexythiazox and etoxazole in Tetranychus urticae

    Science.gov (United States)

    Demaeght, Peter; Osborne, Edward J.; Odman-Naresh, Jothini; Grbić, Miodrag; Nauen, Ralf; Merzendorfer, Hans

    2014-01-01

    The acaricides clofentezine, hexythiazox and etoxazole are commonly referred to as ‘mite growth inhibitors’, and clofentezine and hexythiazox have been used successfully for the integrated control of plant mite pests for decades. Although they are still important today, their mode of action has remained elusive. Recently, a mutation in chitin synthase 1 (CHS1) was linked to etoxazole resistance. In this study, we identified and investigated a T. urticae strain (HexR) harboring recessive, monogenic resistance to each of hexythiazox, clofentezine, and etoxazole. To elucidate if there is a common genetic basis for the observed cross-resistance, we adapted a previously developed bulk segregant analysis method to map with high resolution a single, shared resistance locus for all three compounds. This finding indicates that the underlying molecular basis for resistance to all three compounds is identical. This locus is centered on the CHS1 gene, and as supported by additional genetic and biochemical studies, a non-synonymous variant (I1017F) in CHS1 associates with resistance to each of the tested acaricides in HexR. Our findings thus demonstrate a shared molecular mode of action for the chemically diverse mite growth inhibitors clofentezine, hexythiazox and etoxazole as inhibitors of an essential, non-catalytic activity of CHS1. Given the previously documented cross-resistance between clofentezine, hexythiazox and the benzyolphenylurea compounds flufenoxuron and cycloxuron, CHS1 should be also considered as a potential target-site of insecticidal BPUs. PMID:24859419

  11. Natural Occurrence of Tomato leaf curl New Delhi virus in Iranian Cucurbit Crops

    Directory of Open Access Journals (Sweden)

    Sara Yazdani-Khameneh

    2016-06-01

    Full Text Available The main areas for field-grown vegetable production in Iran were surveyed during the years of 2012–2014 to determine the occurrence of begomoviruses infecting these crops. A total of 787 leaf samples were collected from vegetables and some other host plants showing virus-like symptoms and tested by an enzyme-linked immunosorbent assay (ELISA using polyclonal antibodies produced against Tomato yellow leaf curl virus (TYLCV. According to the ELISA results, 81 samples (10.3% positively reacted with the virus antibodies. Begomovirus infections were confirmed by polymerase chain reaction (PCR using previously described TYLCV-specific primer pair TYLCV-Sar/TYLCV-Isr or universal primer pair Begomo-F/Begomo-R. The PCR tests using the primer pair TYLCV-Sar/TYLCV-Isr resulted in the amplification of the expected fragments of ca. 0.67-kb in size for ELISA-positive samples tested from alfalfa, pepper, spinach and tomato plants, confirming the presence of TYLCV. For one melon sample, having a week reaction in ELISA and no reaction in PCR using TYLCV-specific primers, the PCR reaction using the primer pair Begomo-F/Begomo-R resulted in the amplification fragments of the expected size of ca. 2.8 kb. The nucleotide sequences of the DNA amplicons derived from the isolate, Kz-Me198, were determined and compared with other sequences available in GenBank. BLASTN analysis confirmed the begomovirus infection of the sample and showed 99% identities with Tomato leaf curl New Delhi virus (ToLCNDV; phylogenetic analysis supported the results of the database searches. This study reports the natural occurrence of TYLCV in different hosts in Iran. Our results also reveal the emergence of ToLCNDV in Iranian cucurbit crops.

  12. Enhancement of lesion classification using divergence, curl and curvature of skin pattern.

    Science.gov (United States)

    She, Zhishun; Duller, A W G; Fish, P J

    2004-11-01

    The observation that skin pattern tends to be disrupted by malignant but not by benign skin lesions suggests that measurements of skin pattern disruption on simply captured white light optical clinical (WLC) skin images could be a useful contribution to a diagnostic feature set. Previous work which generated a flow field of skin pattern using a measurement of local line direction and variation determined by the minimum eigenvalue and its corresponding eigenvector of the local tensor matrix to measure skin pattern disruption was computationally low cost and encouraging. This paper explores the possibility of extracting new features from the first and second differentiations of this flow field to enhance classification performance. The skin pattern was extracted from WLC skin images by high-pass filtering. The skin line direction was estimated using a local image gradient matrix to produce a flow field of skin pattern. Divergence, curl, mean and Gaussian curvatures of this flow field were computed from the first and second differentiations of this flow field. The difference of these measures combined with skin line direction across the lesion image boundary was used as a lesion classifier. A set of images of malignant melanoma and benign naevi were analysed as above and the scatter plot in a two-dimensional dominant feature space using principal component analysis showed excellent separation of benign and malignant lesions. A receiver operating characteristic plot enclosed an area of 0.96. The experimental results show that the divergence, curl, mean and Gaussian curvatures of the flow field can increase lesion classifier accuracy. Combined with skin line direction they are promising features for distinguishing malignant melanoma from benign lesions and the methods used are computationally efficient which is important if their use is to be considered in clinical practice.

  13. Squash leaf curl virus (SLCV): a serious disease threatening cucurbits production in Palestine.

    Science.gov (United States)

    Ali-Shtayeh, M S; Jamous, R M; Hussein, E Y; Mallah, O B; Abu-Zeitoun, S Y

    2014-04-01

    The incidence of squash leaf curl disease and molecular characterization of the Palestinian isolate of Squash leaf curl virus [SLCV-(PAL)] are described in this study. Symptomatic leaf samples obtained from squash (Cucurbita pepo), watermelon [Citrullus lanatus (Thunb.)], and cucumber (Cucumis sativus L.) plants were tested for SLCV-[PAL] infection by PCR and RCA. SLCV was also found to occur naturally in Chenopodium murale, Convolvulus sp, and Prosporis farcta which showed yellowing. The disease incidence was 85 % in samples collected from Nablus in summer season, while it was 98 % in samples collected from Qalqilia in autumn. On the other hand, SLCV incidence did not exceed 25 % in winter season. The full-length DNA-A and DNA-B genomes of SLCV-[PAL] were amplified and sequenced, and the sequences were deposited in the GenBank. Sequence analysis reveals that SLCV-[PAL] is closely related to other isolates from Lebanon (SLCV-LB2), Jordan (SLCV-JO), Israel (SLCV-IL), and Egypt (SLCV-EG). DNA-A of SLCV-[PAL] showed the highest nucleotide identity (99.4 %) with SLCV-JO, and SLCV-LB2, while DNA-B had the highest nucleotide identity (99.3 %) with SLCV-IL. However, following genome sequencing, it was found that due to two separate point mutations, two viral open reading frames (ORF) were altered in some SLCV Palestinian isolates. The AC2 ORF was extended by 141 nucleotides, while the AC4 ORF was extended by 36 nucleotides.

  14. Characterization, mode of action, and efficacy of twelve silica-based acaricides against poultry red mite (Dermanyssus gallinae) in vitro.

    Science.gov (United States)

    Schulz, Johanna; Berk, Jutta; Suhl, Johanna; Schrader, Lars; Kaufhold, Stefan; Mewis, Inga; Hafez, Hafez Mohammed; Ulrichs, Christian

    2014-09-01

    Poultry red mite infestation still is an unsolved problem in poultry farms. Legal regulations, residue risks, and resistances limit chemical control of mites. Alternatives to chemical acaricides for control of poultry red mite are silica-based products, which have as a main constituent silicon dioxide. The acaricidal effect is attributed to sorptive properties of the particles, which result in the mite's death by desiccation. In the present study, the acaricidal efficacy of 12 products containing natural or synthetic silica, 9 in powder form, and 3 for liquid application was tested under laboratory conditions. Mite mortality was measured at several intervals and the mean lethal time (LT₅₀) determined by Probit analysis after Abbott's correction. The LT₅₀ values of the products significantly differed (Tukey's HSD p < 0.05). LT₅₀ values of powdery formulations ranged from 5.1 to 18.7 h and overlapped with those of the fluid ones which ranged from 5.5 to 12.7 h. In order to explain the differences in efficacy of the tested silica products, further characterizations were carried out. X-ray fluorescence, specific surface, cation exchange capacity (CEC), and water absorption capacity (WAC) were measured. Furthermore, electron microscopy was conducted and different products compared. Silicon dioxide content (ranging from 65 to 89% for powders and 57 to 80% for fluids) had no significant impact on efficacy, while specific surface and CEC (2.4-23.2 mEq 100(-1) g(-1) for powders and 18-30.8 mEq 100(-1) g(-1)) were positively and WAC (1.3-4.4 wt% for powders and 3.3-4.8 wt% for fluids) negatively related to the acaricidal efficacy. Influence of these parameters on acaricidal efficacy was significant according to the results of a stepwise regression analysis (p < 0.01).

  15. The ectoparasite mite Varroa destructor Anderson and Trueman in southeastern Brazil apiaries: effects of the hygienic behavior of Africanized honey bees on infestation rates

    Directory of Open Access Journals (Sweden)

    F.A. Pinto

    2012-10-01

    Full Text Available In Brazil, the ectoparasitic mite of bees Varroa destructor Anderson and Trueman (Acari: Varroidae remains at low levels of infestation causing no major damage. However, with the introduction and possible dominance of a new haplotype (K of the mite, usually found in areas with high infestation rates (IR, it is necessary to monitor and select beehives that are resistant to the pest in order to avoid future problems. Several factors are listed as potentially being responsible for the dynamics of mite infestation, among which hygienic behavior (HB stands out. In this context we sought to evaluate the HB of Africanized honey bees Apis mellifera L. (Hymenoptera: Apidae compared with the mite IR in apiaries of two municipalities of southeastern Brazil (Taubaté and Viçosa. For the municipality of Taubaté, the average IR was 4.9% (3.4 to 5.8%, while the HB averaged 98.6% (96 to 100%. In Viçosa, the average mite IR was found to be 10.0% (5.4 to 21.0% with an average value for HB of 57.7% (0 to 79.0%. Results from this research show that IR and HB were negatively correlated (R = -0.9627, P<0.01, suggesting that hives with higher HB have lower IR.

  16. Dermanyssus gallinae (chicken mite): an underdiagnosed environmental infestation.

    Science.gov (United States)

    Collgros, H; Iglesias-Sancho, M; Aldunce, M J; Expósito-Serrano, V; Fischer, C; Lamas, N; Umbert-Millet, P

    2013-06-01

    Dermanyssus gallinae is a mite that normally parasitizes small birds but may occasionally bite humans. We report an unusual case of an 82-year-old woman who presented with pruritus and bite-like lesions over her trunk. Other members of the household were also affected. On physical examination, mites gallinae, the small size of the mites and the fact that they leave the host after feeding means that they may not be seen at presentation, thus such infestations are likely to be underdiagnosed. Physicians should be aware that infection with this mite is possible even in patients from urban areas, and it should be included in the differential diagnosis of conditions causing recurrent pruritus unresponsive to standard treatments.

  17. Impeding movement of the poultry red mite, Dermanyssus gallinae.

    Science.gov (United States)

    Pritchard, James; Küster, Tatiana; George, David; Sparagano, Olivier; Tomley, Fiona

    2016-07-30

    The poultry red mite, Dermanyssus gallinae, is an economically important hematophagous parasite of commercial egg laying hens, also affecting domesticated birds and companion animals. Conventional control of D. gallinae through acaricidal spraying is often ineffective, creating an urgent need to identify alternative management strategies for commercial and domestic infestations. Whilst integrated pest management is being considered for D. gallinae, the potential of impeding mite 'migration' routes, to either prevent initial infestation or manage established populations, has not been researched. Here we demonstrate that barriers of insecticidal glue, double sided sticky tape and thyme oil can contain D. gallinae within a specified area of a petri dish (78-88% of total mite population) and this level of containment was significantly greater than for negative controls (p values <0.05). Further studies in poultry houses are recommended to investigate the efficacy of these barriers in real world application and identity potential for barriers as a strategy for mite control.

  18. Microbiota of Demodex mites from rosacea patients and controls.

    Science.gov (United States)

    Murillo, Nathalia; Aubert, Jérome; Raoult, Didier

    2014-01-01

    Proliferation of Demodex mites is associated with rosacea. Furthermore, Demodex-associated bacteria were suggested to play a role in the pathogenesis of rosacea. We decided to analyze Demodex microbiota. Mites were collected by standardized skin surface biopsies from patients with erythematotelangiectatic, papulopustular rosacea or from control subjects. The microbiota from each mite was characterized by 16S rRNA clone library approach. The 16S rRNA clone library consisted of 367 clones obtained from 73 extracts originating from 5 samples per study group (ETR, PPR or healthy subjects). A total of 86 species were identified with 36 as Demodex-specific microbiota. In the papulopustular group, proportions of Proteobacteria and Firmicutes increased whereas proportion of Actinobacteria decreased. Here, we report preliminary results on the microbiota of Demodex mites based on a molecular approach showing an unexpected diversity. Differences according to the host status need to be confirmed but open new perspectives for diagnostic of rosacea.

  19. Risk factors and prevalence of Demodex mites in young adults.

    Science.gov (United States)

    Horváth, Andrea; Neubrandt, Dóra Maja; Ghidán, Á; Nagy, K

    2011-06-01

    Demodex mites are ectoparasites often found in follicles of facial skin. Their role in human diseases is under investigation, and a growing number of studies indicated that they contribute to chronic inflammatory conditions of the skin, such as rosacea, blepharitis, otitis externa, alopecia and folliculitis. In our study we tested 96 healthy adults for the presence of Demodex mites. Risk factors influencing presence of mites and skin types of the tested individuals were evaluated. We found Demodex folliculorum or Demodex brevis in 17.7% of the samples, more frequently in males (21.9%) and in older adults (20%). Use of make-up seems to reduce the likelihood of Demodex carriage, while pet ownership, use of shared items and living in close contact with older adults had no significant influence of presence of mites. Demodex positive individuals described their skin to be drier, more prone to erythema, but less for folliculitis compared to Demodex negative subjects.

  20. FDA Approves New Treatment for Dust Mite Allergies

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_163882.html FDA Approves New Treatment for Dust Mite Allergies Odactra ... life," said Dr. Peter Marks, director of the FDA's Center for Biologics Evaluation and Research. "The approval ...

  1. The impact of pesticides on apple mite communities

    OpenAIRE

    Ahmad, Shakeel

    2013-01-01

    Laboratory, field and semi-field experiments have been carried out on the predatory mites Kampimodromus aberrans, Amblyseius andersoni, Typhlodromus pyri and Phytoseius finitimus in order to optimize biological control strategies against phytophagous mites in apple orchards. The first experiment concerned the augmentative releases of K. aberrans in organic and conventional apple orchards. The most frequent insecticides used in organic orchards were pyrethrins and spinosad, whereas neonicotino...

  2. Genome-wide analysis of bHLH transcription factor and involvement in the infection by yellow leaf curl virus in tomato (Solanum lycopersicum).

    Science.gov (United States)

    Wang, Jinyan; Hu, Zhongze; Zhao, Tongmin; Yang, Yuwen; Chen, Tianzi; Yang, Mali; Yu, Wengui; Zhang, Baolong

    2015-02-05

    The basic helix-loop-helix (bHLH) proteins are a superfamily of transcription factors that can bind to specific DNA target sites. They have been well characterized in model plants such as Arabidopsis and rice and have been shown to be important regulatory components in many different biological processes. However, no systemic analysis of the bHLH transcription factor family has yet been reported in tomatoes. Tomato yellow leaf curl virus (TYLCV) threatens tomato production worldwide by causing leaf yellowing, leaf curling, plant stunting and flower abscission. A total of 152 bHLH transcription factors were identified from the entire tomato genome. Phylogenetic analysis of bHLH domain sequences from Arabidopsis and tomato facilitated classification of these genes into 26 subfamilies. The evolutionary and possible functional relationships revealed during this analysis are supported by other criteria, including the chromosomal distribution of these genes, the conservation of motifs and exon/intron structural patterns, and the predicted DNA binding activities within subfamilies. Distribution mapping results showed bHLH genes were localized on the 12 tomato chromosomes. Among the 152 bHLH genes from the tomato genome, 96 bHLH genes were detected in the TYLCV-susceptible and resistant tomato breeding line before (0 dpi) and after TYLCV (357 dpi) infection. As anticipated, gene ontology (GO) analysis indicated that most bHLH genes are related to the regulation of macromolecule metabolic processes and gene expression. Only four bHLH genes were differentially expressed between 0 and 357 dpi. Virus-induced gene silencing (VIGS) of one bHLH genes SlybHLH131 in resistant lines can lead to the cell death. In the present study, 152 bHLH transcription factor genes were identified. One of which bHLH genes, SlybHLH131, was found to be involved in the TYLCV infection through qRT-PCR expression analysis and VIGS validation. The isolation and identification of these bHLH transcription

  3. PCR analysis for Wolbachia in human and canine Demodex mites.

    Science.gov (United States)

    Borgo, Sibylle N; Sattler, Elke C; Hogardt, Michael; Adler, Kristin; Plewig, Gerd

    2009-10-01

    In many skin diseases such as Demodex folliculitis, rosacea- or steroid-induced rosacea Demodex mites are present in abundance and are at least partially held responsible for causing these disorders. Although it is known that these diseases respond well to tetracyclines, it is unclear if this is due to the antiinflammatory effects of the antibiotics or to an antibacterial effect on so far unknown bacteria within the Demodex mites. As in filariasis, where the response to doxycycline can be explained by the presence of Wolbachia within the filarial nematodes, this study was performed to see whether Wolbachia also use Demodex mites as their hosts. Human and canine Demodex mite samples were taken by skin scrapings and tested by PCR for the presence of Wolbachia DNA. Wolbachia pipientis DNA was used as positive control. In none of the DNA extracts, Wolbachia were detected showing no evidence for the presence of these bacteria in Demodex mites. The response of Demodex aggravated or Demodex caused diseases to tetracyclines seems not to be due to the presence of Wolbachia in Demodex mites in contrast to the results seen in filariasis.

  4. Evolution of host range in the follicle mite Demodex kutzeri.

    Science.gov (United States)

    Palopoli, Michael F; Tra, VAN; Matoin, Kassey; Mac, Phuong D

    2016-11-29

    The sequences of four mitochondrial genes were determined for Demodex mites isolated from two distantly related species within the family Cervidae, and identified morphologically as belonging to the species Demodex kutzeri. The sequences were used to test the hypothesis that Demodex are strictly host-specific, and hence cospeciate with their hosts: (1) The estimated divergence time between mites found on elk vs humans agreed closely with a previous estimate of the time that these host species last shared a common ancestor, suggesting cospeciation of mites and hosts, at least over long evolutionary timescales. (2) The extremely low levels of sequence divergence between the mites found on elk vs mule deer hosts indicated that these mites belong to the same species, which suggests that Demodex are able to move across host species boundaries over shorter timescales. Together, the results are consistent with the model that Demodex mites are not strict host-specialists, but instead lose the ability to move between host lineages gradually.

  5. New Wolbachia supergroups detected in quill mites (Acari: Syringophilidae).

    Science.gov (United States)

    Glowska, Eliza; Dragun-Damian, Anna; Dabert, Miroslawa; Gerth, Michael

    2015-03-01

    Wolbachia is the most abundant intracellular bacterial genus infecting a wide range of arthropods and filarial nematodes. Wolbachia have evolved parasitic, mutualistic and commensal relationships with their hosts but in arthropods generally act as reproductive parasites, inducing a wide range of phenotypic effects such as cytoplasmic incompatibility, parthenogenesis, feminization and male-killing. Up to now, the genus has been divided into 14 supergroups successively named A-O. Here, we describe two new Wolbachia supergroups from syringophilid mites (Acari: Cheyletoidea). These obligatory ectoparasites of birds inhabit the quills of feathers in many avian groups. The species of this family reproduce in a haplodiploid mode sensu arrhenotoky and are usually strongly female-biased. Based on the sequences of four protein-coding genes (ftsZ, gltA and groEL and coxA) and the 16S rRNA we identified strains of three Wolbachia supergroups (F and two distinct, yet undescribed ones) in five quill mite species. Our results suggest that in some cases the distribution of the bacteria can be better correlated with the mite's bird host rather than with mite taxonomy as such. The discovery of two new Wolbachia supergroups not only broadens the knowledge of the diversity of this bacterium but also raises questions about potential effects induced in quill mites and transmission mechanisms of the endosymbionts in this peculiar bacteria-quill mite-bird system.

  6. Comparing terpenes from plant essential oils as pesticides for the poultry red mite (Dermanyssus gallinae).

    Science.gov (United States)

    Sparagano, O; Khallaayoune, K; Duvallet, G; Nayak, S; George, D

    2013-11-01

    Resistance to conventional synthetic pesticides has been widely reported in ticks, parasitic mites and other pests of veterinary and medical significance. New and novel approaches to manage these pests are therefore needed to ensure efficient control programmes that can be implemented now and in the future. Recent research in this area has focused on the pesticidal potential of plant essential oils. These products are attractive as pesticide candidates on the grounds of low mammalian toxicity, short environmental persistence and complex chemistries (limiting the development of pest resistance against them). Although issues may exist concerning reliability in efficacy of essential oils, these may be overcome by identifying and developing bioactive oil components for use in pest management. In the current work, three such components (terpenes) found in essential oils (eugenol, geraniol and citral) were tested against the poultry red mite Dermanyssus gallinae. All provided 100% mortality in toxicity tests when undiluted. Even at 1% of this dose, eugenol was 20% effective against experimental pest populations, although the remaining terpenes were largely ineffective at this concentration.

  7. Baseline susceptibility of persea mite (Acari: Tetranychidae) to abamectin and milbemectin in avocado groves in Southern California.

    Science.gov (United States)

    Humeres, Eduardo C; Morse, Joseph G

    2005-01-01

    Persea mite, Oligonychus perseae Tuttle, Baker, and Abatiello, susceptibility to abamectin and milbemectin was evaluated in 2003 to determine baseline susceptibility levels in avocado groves in San Diego and Ventura Counties (California, USA) where more than 70% of the state's avocado production is concentrated. Milbemectin has yet to be used in avocado production in California and abamectin has been available for use since 1999. Baseline susceptibility ratios (in relation to the most susceptible population) of five persea mite field strains to milbemectin varied 2.1- to 2.8-fold at the LC50 and LC90, respectively. The susceptibility of seven field strains to abamectin varied slightly more (2.1- to 3.5-fold) with one strain subjected to seven sprays over the past 4 years showing slight but significant separation of LC50 and LC90's from the most susceptible strain, which is suggestive of the early stages of resistance to this product. Based on these data, baseline susceptibility levels are proposed that might be used to monitor for future persea mite resistance to these chemicals as their use in California avocado production continues.

  8. 小麦MITE扩增体系的建立%Establishment of MITE Amplification System in the Wheat Study

    Institute of Scientific and Technical Information of China (English)

    谢欢; 杨文香; 彭巧慧; 赵丽娟; 刘力伟; 张娜; 刘大群

    2014-01-01

    Thatcher and 23 of wheat leaf rust resistance near isogenic lines in Thatcher background were chosen as materials in this experiment. Research on the establishment of MITE amplification system was carried out. 27 of the 56 primer pairs were amplified stably,reaction system and different annealing temperature of primers were con-firmed for amplification of MITE ( Miniature inverted repeat transposable elements) .%以Thatcher及23个以Thatcher为遗传背景的小麦抗叶锈病近等基因系为材料,开展了MITE扩增体系的建立研究,获得了适合小麦MITE分子标记的扩增体系及不同引物的退火温度,所用56对引物有27对获得稳定扩增。

  9. Volatile compounds from leaves of the African spider plant (Gynandropsis gynandra) with bioactivity against spider mite (Tetranychus urticae)

    DEFF Research Database (Denmark)

    Nyalala, Samuel Odeyo; Petersen, Mikael Agerlin; Grout, Brian William Wilson

    2013-01-01

    Previous studies have demonstrated that Gynandropsis gynandra emits acetonitrile as a foliar volatile from intact plants and isolated leaves, and that this compound is an effective spider mite repellent. This study has used gas chromatography–mass spectrometry to investigate volatile compounds...... emitted from homogenised G. gynandra leaves to evaluate their tissue acetonitrile content and to look for other compounds that might be exploited for the management of spider mites. Acetonitrile was absent from the homogenised tissues of five lines of G. gynandra, studied over two seasons. Thirteen......, and a high constitutive content of them in roses may be of value in targeted plant breeding for enhanced insect resistance. The range of isothiocyanates found in G. gynandra accounts for the bitter taste of the leaves when used as a traditional vegetable in Eastern Africa and provides a target...

  10. Effectiveness of Ectiban, egg oil, Rabon, or Sevin for control of northern fowl mites on laying hens.

    Science.gov (United States)

    McKeen, W D; Loomis, E C; Dunning, L L

    1983-12-01

    Two field trials were conducted on different ranches to compare acaricides for control of northern fowl mite (NFM) on White Leghorn hens. In Trial 1 Ectiban spray and dust treatments were compared to Rabon and Sevin spray-treatments; egg oil, Rabon, and Sevin sprays were tested in Trial 2. Concentration and rates of application followed label recommendations for the registered compounds. In Trial 1 Ectiban spray gave excellent NFM control; Ectiban dust, Rabon, and Sevin spray treatments resulted in poor NFM control. Egg oil and Rabon sprays gave effective NFM control in Trial 2. Sevin, as in Trial 1, gave poor NFM control. The failure of Sevin to control mites both times suggests the possibility of NFM resistance to this chemical.

  11. A scabies mite serpin interferes with complement-mediated neutrophil functions and promotes staphylococcal growth.

    Directory of Open Access Journals (Sweden)

    Pearl M Swe

    2014-06-01

    Full Text Available BACKGROUND: Scabies is a contagious skin disease caused by the parasitic mite Sarcoptes scabiei. The disease is highly prevalent worldwide and known to predispose to secondary bacterial infections, in particular by Streptococcus pyogenes and Staphylococcus aureus. Reports of scabies patients co-infected with methicillin resistant S. aureus (MRSA pose a major concern for serious down-stream complications. We previously reported that a range of complement inhibitors secreted by the mites promoted the growth of S. pyogenes. Here, we show that a recently characterized mite serine protease inhibitor (SMSB4 inhibits the complement-mediated blood killing of S. aureus. METHODOLOGY/PRINCIPAL FINDINGS: Blood killing of S. aureus was measured in whole blood bactericidal assays, counting viable bacteria recovered after treatment in fresh blood containing active complement and phagocytes, treated with recombinant SMSB4. SMSB4 inhibited the blood killing of various strains of S. aureus including methicillin-resistant and methicillin-sensitive isolates. Staphylococcal growth was promoted in a dose-dependent manner. We investigated the effect of SMSB4 on the complement-mediated neutrophil functions, namely phagocytosis, opsonization and anaphylatoxin release, by flow cytometry and in enzyme linked immuno sorbent assays (ELISA. SMSB4 reduced phagocytosis of S. aureus by neutrophils. It inhibited the deposition of C3b, C4b and properdin on the bacteria surface, but did not affect the depositions of C1q and MBL. SMSB4 also inhibited C5 cleavage as indicated by a reduced C5b-9 deposition. CONCLUSIONS/SIGNIFICANCE: We postulate that SMSB4 interferes with the activation of all three complement pathways by reducing the amount of C3 convertase formed. We conclude that SMSB4 interferes with the complement-dependent killing function of neutrophils, thereby reducing opsonization, phagocytosis and further recruitment of neutrophils to the site of infection. As a

  12. Resistance in Cucumis sativus L. to tetranychus urticae Koch

    NARCIS (Netherlands)

    Ponti, de O.M.B.

    1980-01-01

    Chapter 1The role of plant breeding and particularly of host plant resistance in integrated control is discussed. Host plant resistance to insects and mites, especially to Tetranychus urticae is reviewed. A standard terminology for disease and pest resistance is recommended.Chapter 2The relationship

  13. Mite species inhabiting commercial bumblebee (Bombus terrestris) nests in Polish greenhouses.

    Science.gov (United States)

    Rożej, Elżbieta; Witaliński, Wojciech; Szentgyörgyi, Hajnalka; Wantuch, Marta; Moroń, Dawid; Woyciechowski, Michal

    2012-03-01

    Nests of social insects are usually inhabited by various mite species that feed on pollen, other micro-arthropods or are parasitic. Well-known negative effects of worldwide economic importance are caused by mites parasitizing honeybee colonies. Lately, attention has focused on the endoparasitic mite Locustacarus buchneri that has been found in commercial bumblebees. However, little is known of other mites associated with commercial bumblebee nests. Transportation of commercial bumblebee colonies with unwanted residents may introduce foreign mite species to new localities. In this study, we assessed the prevalence and species composition of mites associated with commercial bumblebee nests and determined if the mites are foreign species for Poland and for Europe. The study was conducted on 37 commercial bumblebee nests from two companies (Dutch and Israeli), originating from two greenhouses in southern Poland, and on 20 commercial bumblebee colonies obtained directly from suppliers. The species composition and abundance of mites inhabiting commercial bumblebee nests were determined. Seven mite species from three families were found in nests after greenhouse exploitation. The predominant mite species was Tyrophagus putrescentiae (Acaridae) that was a 100-fold more numerous than representatives of the family Laelapidae (Hypoaspis marginepilosa, H. hyatti, H. bombicolens). Representatives of Parasitidae (Parasitellus fucorum, P. crinitus, P. ignotus) were least numerous. All identified mite species are common throughout Europe, foreign species were not found. Mites were not detected in nests obtained directly from suppliers. We conclude that probably bumblebee nests are invaded by local mite species during greenhouse exploitation.

  14. Immunotherapy with the storage mite lepidoglyphus destructor.

    Science.gov (United States)

    Armentia-Medina, A; Tapias, J A; Martín, J F; Ventas, P; Fernández, A

    1995-01-01

    We carried out a double-blind clinical trial of immunotherapy on 35 patients sensitized to the storage mite Lepidoglyphus destructor (Ld). Before and after 12 months of specific hyposensitization (Abelló Lab., Spain) we performed in vivo (skin tests with Ld, methacholine and challenge tests), and in vitro tests (specific IgE, IgG, IgG1 and IgG4 to Ld and specific IgE, IgG, IgG1 and IgG4 to their major allergen Lep dI). We also monitored the efficacy and safety of the immunotherapy with clinical and analytical controls (symptoms and medication score, detection of immune complexes). After therapy we found a significant decrease in specific skin reactivity, dose of positive challenge tests, and hyperresponsiveness to methacholine. Sputum eosinophilia decreased. Specific IgE to Ld was increased and we also observed an increase in specific IgG1 and IgG4 to Ld and Lep DI. The placebo group showed no changes in these variables. There were no severe secondary reactions after treatment with the extract. Patients-self-evaluation was favourable and their labour absence decreased. No development of circulating immune complexes was associated with this immunotherapy.

  15. Replication of Tomato Yellow Leaf Curl Virus in Its Whitefly Vector, Bemisia tabaci.

    Science.gov (United States)

    Pakkianathan, Britto Cathrin; Kontsedalov, Svetlana; Lebedev, Galina; Mahadav, Assaf; Zeidan, Muhammad; Czosnek, Henryk; Ghanim, Murad

    2015-10-01

    Tomato yellow leaf curl virus (TYLCV) is a begomovirus transmitted exclusively by the whitefly Bemisia tabaci in a persistent, circulative manner. Replication of TYLCV in its vector remains controversial, and thus far, the virus has been considered to be nonpropagative. Following 8 h of acquisition on TYLCV-infected tomato plants or purified virions and then transfer to non-TYLCV-host cotton plants, the amounts of virus inside whitefly adults significantly increased (>2-fold) during the first few days and then continuously decreased, as measured by the amounts of genes on both virus DNA strands. Reported alterations in insect immune and defense responses upon virus retention led us to hypothesize a role for the immune response in suppressing virus replication. After virus acquisition, stress conditions were imposed on whiteflies, and the levels of three viral gene sequences were measured over time. When whiteflies were exposed to TYLCV and treatment with two different pesticides, the virus levels continuously increased. Upon exposure to heat stress, the virus levels gradually decreased, without any initial accumulation. Switching of whiteflies between pesticide, heat stress, and control treatments caused fluctuating increases and decreases in virus levels. Fluorescence in situ hybridization analysis confirmed these results and showed virus signals inside midgut epithelial cell nuclei. Combining the pesticide and heat treatments with virus acquisition had significant effects on fecundity. Altogether, our results demonstrate for the first time that a single-stranded DNA plant virus can replicate in its hemipteran vector. Plant viruses in agricultural crops are of great concern worldwide. Many of them are transmitted from infected to healthy plants by insects. Persistently transmitted viruses often have a complex association with their vectors; however, most are believed not to replicate within these vectors. Such replication is important, as it contributes to the

  16. Numerical study on the curling and warping of hardened rigid pavement slabs

    Science.gov (United States)

    Qin, Yinghong

    In-service hardened concrete pavement suffers from environmental loadings caused by curling and warping of the slab. Traditionally, these loadings are computed on the basis of treating the slab as an elastic material, and of evaluating separately the curling and warping components. This dissertation simulates temperature distribution and moisture distribution through the slabs by use of a developed numerical model that couples the heat transfer and moisture transport. The computation of environmental loadings treats the slab as an elastic-viscous material, which considers the relaxation behavior and Pickett effect of the concrete. The heat transfer model considers the impacts of solar radiation, wind speed, air temperature, pavement slab albedo, etc. on the pavement temperature distribution. This dissertation assesses the difference between documented models that aim to predict pavement temperature, highlighting their pros and cons. The moisture transport model is unique for the documented models; it mimics the wetting and drying events occurring at the slab surface. These events are estimated by a proposed statistical algorithm, which is verified by field rainfall data. Analysis of the predicted results examines on the roles of the local air RH (relative humidity), wind speed, rainy pattern in the moisture distribution through the slab. The findings reveal that seasonal air RH plays a decisive role on the slab's moisture distribution; but wind speed and its daily variation, daily RH variation, and seasonal rainfall pattern plays only a secondary role. This dissertation sheds light on the computation of environmental loadings that in-service pavement slabs suffer from. Analysis of the computed stresses centers on the stress relaxation near the surface, stress evolution after the curing ends, and the impact of construction season on the stress's magnitude. An unexpected finding is that the total environmental loadings at the cyclically-stable state divert from the

  17. Neonicotinoid Insecticides Alter Induced Defenses and Increase Susceptibility to Spider Mites in Distantly Related Crop Plants

    Science.gov (United States)

    Szczepaniec, Adrianna; Raupp, Michael J.; Parker, Roy D.; Kerns, David; Eubanks, Micky D.

    2013-01-01

    Background Chemical suppression of arthropod herbivores is the most common approach to plant protection. Insecticides, however, can cause unintended, adverse consequences for non-target organisms. Previous studies focused on the effects of pesticides on target and non-target pests, predatory arthropods, and concomitant ecological disruptions. Little research, however, has focused on the direct effects of insecticides on plants. Here we demonstrate that applications of neonicotinoid insecticides, one of the most important insecticide classes worldwide, suppress expression of important plant defense genes, alter levels of phytohormones involved in plant defense, and decrease plant resistance to unsusceptible herbivores, spider mites Tetranychus urticae (Acari: Tetranychidae), in multiple, distantly related crop plants. Methodology/Principal Findings Using cotton (Gossypium hirsutum), corn (Zea mays) and tomato (Solanum lycopersicum) plants, we show that transcription of phenylalanine amonia lyase, coenzyme A ligase, trypsin protease inhibitor and chitinase are suppressed and concentrations of the phytohormone OPDA and salicylic acid were altered by neonicotinoid insecticides. Consequently, the population growth of spider mites increased from 30% to over 100% on neonicotinoid-treated plants in the greenhouse and by nearly 200% in the field experiment. Conclusions/Significance Our findings are important because applications of neonicotinoid insecticides have been associated with outbreaks of spider mites in several unrelated plant species. More importantly, this is the first study to document insecticide-mediated disruption of plant defenses and link it to increased population growth of a non-target herbivore. This study adds to growing evidence that bioactive agrochemicals can have unanticipated ecological effects and suggests that the direct effects of insecticides on plant defenses should be considered when the ecological costs of insecticides are evaluated. PMID

  18. Acaricide residues in laying hens naturally infested by red mite Dermanyssus gallinae.

    Directory of Open Access Journals (Sweden)

    Marianna Marangi

    Full Text Available In the poultry industry, control of the red mite D. gallinae primarily relies worldwide on acaricides registered for use in agriculture or for livestock, and those most widely used are carbamates, followed by amidines, pyrethroids and organophosphates. Due to the repeated use of acaricides--sometimes in high concentrations--to control infestation, red mites may become resistant, and acaricides may accumulate in chicken organs and tissues, and also in eggs. To highlight some situations of misuse/abuse of chemicals and of risk to human health, we investigated laying hens, destined to the slaughterhouse, for the presence of acaricide residues in their organs and tissues. We used 45 hens from which we collected a total of 225 samples from the following tissues and organs: skin, fat, liver, muscle, hearth, and kidney. In these samples we analyzed the residual contents of carbaryl and permethrin by LC-MS/MS.Ninety-one (40.4% samples were positive to carbaryl and four samples (1.7% were positive to permethrin. Concentrations of carbaryl exceeding the detection limit (0.005 ppm were registered in the skin and fat of birds from two farms (p<0.01, although these concentrations remained below the maximum residue limit (MRLs (0.05 ppm (p<0.01. All organs/tissues of hens from a third farm were significantly more contaminated, with skin and muscle samples exceeding the MRL (0.05 ppm (p<0.01 of carbaryl in force before its use was banned. Out of 45 chickens tested, 37 (82.2% were found to be contaminated by carbaryl, and 4 (8.8% by permethrin. The present study is the first report on the presence of pesticides banned by the EU (carbaryl or not licensed for use (permethrin in the organs and tissues of laying hens, which have been treated against red mites, and then slaughtered for human consumption at the end of their life cycle.

  19. Acaricide residues in laying hens naturally infested by red mite Dermanyssus gallinae.

    Science.gov (United States)

    Marangi, Marianna; Morelli, Vincenzo; Pati, Sandra; Camarda, Antonio; Cafiero, Maria Assunta; Giangaspero, Annunziata

    2012-01-01

    In the poultry industry, control of the red mite D. gallinae primarily relies worldwide on acaricides registered for use in agriculture or for livestock, and those most widely used are carbamates, followed by amidines, pyrethroids and organophosphates. Due to the repeated use of acaricides--sometimes in high concentrations--to control infestation, red mites may become resistant, and acaricides may accumulate in chicken organs and tissues, and also in eggs. To highlight some situations of misuse/abuse of chemicals and of risk to human health, we investigated laying hens, destined to the slaughterhouse, for the presence of acaricide residues in their organs and tissues. We used 45 hens from which we collected a total of 225 samples from the following tissues and organs: skin, fat, liver, muscle, hearth, and kidney. In these samples we analyzed the residual contents of carbaryl and permethrin by LC-MS/MS.Ninety-one (40.4%) samples were positive to carbaryl and four samples (1.7%) were positive to permethrin. Concentrations of carbaryl exceeding the detection limit (0.005 ppm) were registered in the skin and fat of birds from two farms (p<0.01), although these concentrations remained below the maximum residue limit (MRLs) (0.05 ppm) (p<0.01). All organs/tissues of hens from a third farm were significantly more contaminated, with skin and muscle samples exceeding the MRL (0.05 ppm) (p<0.01) of carbaryl in force before its use was banned. Out of 45 chickens tested, 37 (82.2%) were found to be contaminated by carbaryl, and 4 (8.8%) by permethrin. The present study is the first report on the presence of pesticides banned by the EU (carbaryl) or not licensed for use (permethrin) in the organs and tissues of laying hens, which have been treated against red mites, and then slaughtered for human consumption at the end of their life cycle.

  20. High order gradient, curl and divergence conforming spaces, with an application to NURBS-based IsoGeometric Analysis

    CERN Document Server

    Hiemstra, R R; Gerritsma, M I

    2012-01-01

    Conservation laws, in for example, electromagnetism, solid and fluid mechanics, allow an exact discrete representation in terms of line, surface and volume integrals. We develop high order interpolants, from any basis that is a partition of unity, that satisfy these integral relations exactly, at cell level. The resulting gradient, curl and divergence conforming spaces have the property that the conservation laws become completely independent of the basis functions. This means that the conservation laws are exactly satisfied even on curved meshes. As an example, we develop high order gradient, curl and divergence conforming spaces from NURBS - non uniform rational B-splines - and thereby generalize the compatible spaces of B-splines developed by Buffa et al.[1]. We give several examples of 2D Stokes flow calculations which result, amongst others, in a point wise divergence free velocity field.

  1. Nucleotide sequence and intergeminiviral homologies of the DNA-A of papaya leaf curl geminivirus from India.

    Science.gov (United States)

    Saxena, S; Hallan, V; Singh, B P; Sane, P V

    1998-06-01

    Coat protein gene, rep protein gene and intergenic region of the genome of a whitefly transmitted geminivirus (WTG) causing severe leaf curl in papaya plants were PCR amplified, cloned and sequenced. Comparison of the amino acid sequence of the putative coat protein product of papaya leaf curl virus (PLCV) with some other mono and bipartite WTGs revealed a maximum of 89.8% homology with Indian cassava mosaic virus. The genomic organization of PLCV-India is similar to other WTGs with bipartite genomes. Comparison of the coat protein N-terminal 70 amino acid sequence (and other biological features) of PLCV with other geminiviruses shows that PLCV is a distinct geminivirus from India and is related to WTGs from the old world.

  2. Molecular and biological characterization of a new Tomato mild yellow leaf curl Aragua virus strain producing severe symptoms in tomato.

    Science.gov (United States)

    Romay, Gustavo; Chirinos, Dorys T; Geraud-Pouey, Francis; Gillis, Annika; Mahillon, Jacques; Desbiez, Cécile; Bragard, Claude

    2017-06-20

    Tomato mild yellow leaf curl Aragua virus (ToMYLCV) is a begomovirus first reported infecting tomato (Solanum lycopersicum) and milkweed (Euphorbia heterophylla) in Venezuela. In this study, a ToMYLCV isolate (Zulia-219) was completely sequenced and its host range was evaluated. The DNA-A and DNA-B components of isolate Zulia-219 showed 93 and 85% nucleotide sequence identity with the respective counterparts of the ToMYLCV type strain. According to current demarcation criteria for begomovirus species, Zulia-219 is a new strain of ToMYLCV. Interestingly, tomato plants inoculated with ToMYLCV Zulia-219 displayed severe symptoms, including severe chlorotic leaf curling, in contrast to mild symptoms associated with the type strain of this begomovirus. These results indicate potential risks associated with this new ToMYLCV strain for tomato production in Venezuela.

  3. Effectiveness of Cyantraniliprole for Managing Bemisia tabaci (Hemiptera: Aleyrodidae) and Interfering with Transmission of Tomato Yellow Leaf Curl Virus on Tomato.

    Science.gov (United States)

    Caballero, Rafael; Schuster, David J; Peres, Natalia A; Mangandi, Jozer; Hasing, Tomas; Trexler, Fred; Kalb, Steve; Portillo, Héctor E; Marçon, Paula C; Annan, I B

    2015-06-01

    Cyantraniliprole is the second xylem-systemic active ingredient in the new anthranilic diamide class. Greenhouse (2006), growth chamber (2007), and field studies (2009-2010) were conducted to determine the efficacy of cyantraniliprole for managing Bemisia tabaci (Gennadius) biotype B and in interfering with transmission of tomato yellow leaf curl virus (TYLCV) by this whitefly. Cyantraniliprole applied as soil treatments (200 SC) or foliar sprays (100 OD) provided excellent adult whitefly control, TYLCV suppression, and reduced oviposition and nymph survival, comparable to current standards. The positive results observed in these greenhouse experiments with a high level of insect pressure (10× the field threshold of one adult per plant) and disease pressure (five adults per plant, with a high level of confidence that TYLCV virulent adults were used), indicate a great potential for cyantraniliprole to be used in a whitefly management program. Field evaluations of soil drench treatments confirmed the suppression of TYLCV transmission demonstrated in the greenhouse studies. Field studies in 2009 and 2010 showed that cyantraniliprole (200 SC) provided TYLCV suppression for 2 wk after a drench application, when using a susceptible (2009) or imidacloprid-tolerant (2010) whitefly population. Cyantraniliprole was demonstrated to be a promising tool for management of TYLCV in tomato production, which is very difficult and expensive, and which has limited options. The integration of cyantraniliprole into a resistance management program will help to ensure the continued sustainability of this and current insecticides used for the management of insect vectors, including whiteflies and the TYLCV they spreads.

  4. Acaricide resistance and resistance mechanisms in Tetranychus urticae populations from rose greenhouses in the Netherlands

    NARCIS (Netherlands)

    Khajehali, J.; Van Nieuwenhuyse, P.; Demaeght, P.; Tirry, L.; Van Leeuwen, T.

    2011-01-01

    BACKGROUND: Spider mites are important crop pests that rapidly develop resistance to acaricides. To investigate whether acaricide resistance is a threat to greenhouse rose culture in the Netherlands, the susceptibility of 15 strains of Tetranychus urticae was tested to several currently used acarici

  5. Acaricide resistance and resistance mechanisms in Tetranychus urticae populations from rose greenhouses in the Netherlands

    NARCIS (Netherlands)

    Khajehali, J.; Van Nieuwenhuyse, P.; Demaeght, P.; Tirry, L.; Van Leeuwen, T.

    2011-01-01

    BACKGROUND: Spider mites are important crop pests that rapidly develop resistance to acaricides. To investigate whether acaricide resistance is a threat to greenhouse rose culture in the Netherlands, the susceptibility of 15 strains of Tetranychus urticae was tested to several currently used

  6. The predatory mite Typhlodromalus aripo prefers green-mite induced plant odours from pubescent cassava varieties.

    Science.gov (United States)

    Onzo, Alexis; Hanna, Rachid; Sabelis, Maurice W

    2012-12-01

    It is well known that plant-inhabiting predators use herbivore-induced plant volatiles to locate herbivores being their prey. Much less known, however, is the phenomenon that genotypes of the same host plant species vary in the attractiveness of these induced chemical signals, whereas they also differ in characteristics that affect the predator's foraging success, such as leaf pubescence. In a series of two-choice experiments (using a Y-tube olfactometer) we determined the preference of Typhlodromalus aripo for pubescent versus glabrous cassava cultivars infested with the cassava green mite Mononychellus tanajoa and also the preference for cultivars within each of the two groups. We found that when offered a choice between pubescent and glabrous cassava cultivars (either apex or leaves), T. aripo was significantly more attracted to pubescent cultivars. For each cultivar, M. tanajoa infested leaves and apices were equally attractive to T. aripo. There was however some variation in the response of T. aripo to M. tanajoa-infested plant parts within the group of pubescent cultivars, as well as within the group of glabrous cultivars. Our study confirms not only that T. aripo uses herbivore-induced plant volatiles to search for prey in cassava fields, but it also shows that it can discriminate between glabrous and pubescent cultivars and prefers the latter. This knowledge can be useful in selecting cultivars that are attractive and suitable to T. aripo, which, in turn, may promote biological control of the cassava green mite.

  7. Irradiation as a phytosanitary treatment for mites of the specie Tyrophagus putrescentiae (Acari: Acaridae)

    Energy Technology Data Exchange (ETDEWEB)

    Arthur, Valter, E-mail: varthur@cena.usp.b [Centro de Energia Nuclear na Agricultura (CENA/USP), Piracicaba, SP (Brazil). Lab. de Radiobiologia e Ambiente; Mineiro, Jeferson L.C. [Instituto Biologico de Sao Paulo/APTA, Sao Paulo, SP (Brazil). Lab. de Entomologia Economico

    2009-07-01

    In great populations mites of the specie Tyrophagus putrescentiae can cause damages in stored products. The work had as objective to evaluate the effects of the gamma radiation of the Cobalt-60 to control the mites of the specie T. putrescentiae. The mites were irradiated with doses of 0 (control), 300, 400, 500, 600, 700, 800 Gy, in a source of Cobalt-60 type Gammacell-220, with a dose rate of 0.718 kGy/hour. Each treatment consisted of four repetitions containing 10 mites each, in a total of approximately 40 mites for treatment. The evaluations were daily, being counted the number of mites died, put eggs and emerged larvae. Based on the obtained results it was concluded that the dose sterilizing for the mites of this specie was of 300 Gy. Already the dose of 600 Gy induced the total mortality of the mites after 11 days of the irradiation process. (author)

  8. Mite (Arthropoda, Acari associates of palms (Arecaceae in Brazil I: present status and new records

    Directory of Open Access Journals (Sweden)

    Dalva L. Q. Santana

    1998-12-01

    Full Text Available This paper presents 72 new records and 10 records from literature on the distribuition of nine species of phytophagous mites and nine species of predatory mites from 13 species of palms in 13 Brazilian States.

  9. Deformed wing virus: replication and viral load in mites (Varroa destructor).

    Science.gov (United States)

    Gisder, Sebastian; Aumeier, Pia; Genersch, Elke

    2009-02-01

    Deformed wing virus (DWV) normally causes covert infections but can have devastating effects on bees by inducing morphological deformity or even death when transmitted by the ectoparasitic mite Varroa destructor. In order to determine the role of V. destructor in the development of crippled wings, we analysed individual mites for the presence and replication of DWV. The results supported the correlation between viral replication in mites and morphologically deformed bees. Quantification of viral genome equivalents revealed that mites capable of inducing an overt DWV infection contained 10(10)-10(12) genome equivalents per mite. In contrast, mites which could not induce crippled wings contained a maximum of only 10(8) viral genome equivalents per mite. We conclude that the development of crippled wings not only depends on DWV transmission by V. destructor but also on viral replication in V. destructor and on the DWV titre in the parasitizing mites.

  10. Ocular symptoms reported by patients infested with Demodex mites.

    Science.gov (United States)

    Sędzikowska, Aleksandra; Osęka, Maciej; Grytner-Zięcina, Barbara

    2016-12-01

    The purpose of this study was to determine subjective ocular symptoms occurring in patients infested with Demodex. The number of Demodex mites in the obtained material that correlated with the appearance of ocular symptoms was estimated. The study material were eyelashes collected from 1499 patients. The material were observed under a light microscope. T-test, the logistic regression method, and Pearson correlation coefficient were used for the analysis. Demodex mites were detected in 47% patients. The mean ages of infected women and men were 64 and 59 years, respectively. 64% infected patients complained of one or more ophthalmological symptoms. The most commonly reported symptoms included itching (28%), redness of eyelids (21%), and watery eyes (15%). Positive correlation was found between itching, redness, pain, purulence or eyelash loss and the presence of Demodex. The mentioned symptoms increase the probability of Demodex infestation in a statistically significant manner (pDemodex was revealed by the study. The threshold average number of seven Demodex mites per eight collected eyelashes with which the risk of the occurrence of an ocular symptom increases significantly was defined. In patients with a low number of Demodex mites, symptoms may be absent. The risk of the occurrence of ocular symptom in patients with demodicosis increases with the increase in the average number of Demodex mites.

  11. Disentangling mite predator-prey relationships by multiplex PCR.

    Science.gov (United States)

    Pérez-Sayas, Consuelo; Pina, Tatiana; Gómez-Martínez, María A; Camañes, Gemma; Ibáñez-Gual, María V; Jaques, Josep A; Hurtado, Mónica A

    2015-11-01

    Gut content analysis using molecular techniques can help elucidate predator-prey relationships in situations in which other methodologies are not feasible, such as in the case of trophic interactions between minute species such as mites. We designed species-specific primers for a mite community occurring in Spanish citrus orchards comprising two herbivores, the Tetranychidae Tetranychus urticae and Panonychus citri, and six predatory mites belonging to the Phytoseiidae family; these predatory mites are considered to be these herbivores' main biological control agents. These primers were successfully multiplexed in a single PCR to test the range of predators feeding on each of the two prey species. We estimated prey DNA detectability success over time (DS50), which depended on the predator-prey combination and ranged from 0.2 to 18 h. These values were further used to weight prey detection in field samples to disentangle the predatory role played by the most abundant predators (i.e. Euseius stipulatus and Phytoseiulus persimilis). The corrected predation value for E. stipulatus was significantly higher than for P. persimilis. However, because this 1.5-fold difference was less than that observed regarding their sevenfold difference in abundance, we conclude that P. persimilis is the most effective predator in the system; it preyed on tetranychids almost five times more frequently than E. stipulatus did. The present results demonstrate that molecular tools are appropriate to unravel predator-prey interactions in tiny species such as mites, which include important agricultural pests and their predators.

  12. Repeatability of feather mite prevalence and intensity in passerine birds.

    Directory of Open Access Journals (Sweden)

    Javier Diaz-Real

    Full Text Available Understanding why host species differ so much in symbiont loads and how this depends on ecological host and symbiont traits is a major issue in the ecology of symbiosis. A first step in this inquiry is to know whether observed differences among host species are species-specific traits or more related with host-symbiont environmental conditions. Here we analysed the repeatability (R of the intensity and the prevalence of feather mites to partition within- and among-host species variance components. We compiled the largest dataset so far available: 119 Paleartic passerine bird species, 75,944 individual birds, ca. 1.8 million mites, seven countries, 23 study years. Several analyses and approaches were made to estimate R and adjusted repeatability (R(adj after controlling for potential confounding factors (breeding period, weather, habitat, spatial autocorrelation and researcher identity. The prevalence of feather mites was moderately repeatable (R = 0.26-0.53; R(adj = 0.32-0.57; smaller values were found for intensity (R = 0.19-0.30; R(adj = 0.18-0.30. These moderate repeatabilities show that prevalence and intensity of feather mites differ among species, but also that the high variation within species leads to considerable overlap among bird species. Differences in the prevalence and intensity of feather mites within bird species were small among habitats, suggesting that local factors are playing a secondary role. However, effects of local climatic conditions were partially observed for intensity.

  13. A rice Stowaway MITE for gene transfer in yeast.

    Directory of Open Access Journals (Sweden)

    Isam Fattash

    Full Text Available Miniature inverted repeat transposable elements (MITEs lack protein coding capacity and often share very limited sequence similarity with potential autonomous elements. Their capability of efficient transposition and dramatic amplification led to the proposition that MITEs are an untapped rich source of materials for transposable element (TE based genetic tools. To test the concept of using MITE sequence in gene transfer, a rice Stowaway MITE previously shown to excise efficiently in yeast was engineered to carry cargo genes (neo and gfp for delivery into the budding yeast genome. Efficient excision of the cargo gene cassettes was observed even though the excision frequency generally decreases with the increase of the cargo sizes. Excised elements insert into new genomic loci efficiently, with about 65% of the obtained insertion sites located in genes. Elements at the primary insertion sites can be remobilized, frequently resulting in copy number increase of the element. Surprisingly, the orientation of a cargo gene (neo on a construct bearing dual reporter genes (gfp and neo was found to have a dramatic effect on transposition frequency. These results demonstrated the concept that MITE sequences can be useful in engineering genetic tools to deliver cargo genes into eukaryotic genomes.

  14. Large-Deformation Curling Actuators Based on Carbon Nanotube Composite: Advanced-Structure Design and Biomimetic Application.

    Science.gov (United States)

    Chen, Luzhuo; Weng, Mingcen; Zhou, Zhiwei; Zhou, Yi; Zhang, Lingling; Li, Jiaxin; Huang, Zhigao; Zhang, Wei; Liu, Changhong; Fan, Shoushan

    2015-12-22

    In recent years, electroactive polymers have been developed as actuator materials. As an important branch of electroactive polymers, electrothermal actuators (ETAs) demonstrate potential applications in the fields of artificial muscles, biomimetic devices, robotics, and so on. Large-shape deformation, low-voltage-driven actuation, and ultrafast fabrication are critical to the development of ETA. However, a simultaneous optimization of all of these advantages has not been realized yet. Practical biomimetic applications are also rare. In this work, we introduce an ultrafast approach to fabricate a curling actuator based on a newly designed carbon nanotube and polymer composite, which completely realizes all of the above required advantages. The actuator shows an ultralarge curling actuation with a curvature greater than 1.0 cm(-1) and bending angle larger than 360°, even curling into a tubular structure. The driving voltage is down to a low voltage of 5 V. The remarkable actuation is attributed not only to the mismatch in the coefficients of thermal expansion but also to the mechanical property changes of materials during temperature change. We also construct an S-shape actuator to show the possibility of building advanced-structure actuators. A weightlifting walking robot is further designed that exhibits a fast-moving motion while lifting a sample heavier than itself, demonstrating promising biomimetic applications.

  15. Detection and quantitation of the new world Squash leaf curl virus by TaqMan real-time PCR.

    Science.gov (United States)

    Abrahamian, Peter E; Abou-Jawdah, Yusuf

    2013-07-01

    Squash leaf curl diseases are caused by distinct virus species that are separated into two major phylogenetic groups, western and eastern hemisphere groups. The western group includes the new world Squash leaf curl virus (SLCV) which causes major losses to cucurbit production and induces severe stunting and leaf curl in squash plants. A TaqMan-based real time polymerase chain reaction (qPCR) assay has been developed for detection and quantitation of SLCV. Designed primers and probe targeted the AV1 (coat protein) gene and in silico analysis showed that they detect a large number of SLCV isolates. The developed assay could detect the virus in 18fg of total nucleic acid and 30 genomic units. The qPCR assay was about 1000 times more sensitive than PCR and amplified successfully SLCV from a wide range of cucurbit hosts and from viruliferous whiteflies. The developed qPCR assay should be suitable for detection and quantitation purposes for all reported SLCV isolates of the western hemisphere.

  16. Deletional analysis of functional regions of complementary sense promoter from cotton leaf curl virus

    Institute of Scientific and Technical Information of China (English)

    谢迎秋; 刘玉乐; 朱祯

    2000-01-01

    Complementary sense promoter from cotton leaf curl virus (CLCuV) is a novel plant promoter for genetic engineering that could drive high-level foreign gene expression in plant. To determine the optimal promoter sequence for gene expression, CLCuV promoter was deleted from its 5’ end to form promoter fragments with five different lengths, and chimeric gus genes were constructed using the promoterdeletion. These vectors were delivered into Agrobacterium and tobacco (Nicotiana tabacum L cv. Xanthi) plants which were transformed by leaf discs method. GUS activity of transgenic plants was measured. The results showed that GUS activities with the promoter deleted to -287 and -271 from the translation initiation site were respectively about five and three times that of full-length promoter. There exists a c/s-element which is important for the expressing activity in phloem from -271 to -176. Deletion from -176 to -141 resulted in a 20-30-fold reduction in GUS activity in leaves with weak activity in leaves and

  17. Curling probe measurement of large-volume pulsed plasma confined by surface magnetic field

    Science.gov (United States)

    Pandey, Anil; Sakakibara, Wataru; Matsuoka, Hiroyuki; Nakamura, Keiji; Sugai, Hideo; Chubu University Team; DOWA Thermotech Collaboration

    2015-09-01

    Curling probe (CP) has recently been developed which enables the local electron density measurement even in plasma for non-conducting film CVD. The electron density is obtained from a shift of resonance frequency of spiral antenna in discharge ON and OFF monitored by a network analyzer (NWA). In case of a pulsed glow discharge, synchronization of discharge pulse with frequency sweep of NWA must be established. In this paper, we report time and space-resolved CP measurement of electron density in a large volume plasma (80 cm diameter, 110 cm length) confined by surface magnetic field (multipole cusp field ~0.03 T). For plasma-aided modification of metal surface, the plasma is produced by 1 kV glow discharge at pulse frequency of 0.3 - 25 kHz with various duty ratio in gas (Ar, N2, C2H2) at pressure ~ 1 Pa. A radially movable CP revealed a remarkable effect of surface magnetic confinement: detach of plasma from the vessel wall and a fairly uniform plasma in the central region. In afterglow phase, the electron density was observed to decrease much faster in C2H2 discharge than in Ar discharge.

  18. Curling probe measurement of a large-volume pulsed plasma with surface magnetic confinement

    Science.gov (United States)

    Pandey, A.; Tashiro, H.; Sakakibara, W.; Nakamura, K.; Sugai, H.

    2016-12-01

    A curling probe (CP) based on microwave resonance is applied to the measurement of electron density in a pulsed DC glow discharge under surface magnetic confinement (SMC) provided by a number of permanent magnets on a chamber wall. Owing to the SMC effects, a 1 m scale large-volume plasma is generated by a relatively low voltage (~1 kV) at low pressure (~1 Pa) in various gases (Ar, CH4, and C2H2). Temporal variation of the electron density is measured for pulse frequency f  =  0.5-25 kHz for various discharge-on times (T ON) with a high resolution time (~0.2 µs), using the on-point mode. In general, the electron density starts to increase at time t  =  0 after turn-on of the discharge voltage, reaches peak density at t  =  T ON, and then decreases after turn-off. The peak electron density is observed to increase with the pulse frequency f for constant T ON owing to the residual plasma. This dependence is successfully formulated using a semi-empirical model. The spatio-temporal evolution of the cathode sheath in the pulsed discharge is revealed by a 1 m long movable CP. The measured thickness of the high-voltage cathode fall in a steady state coincides with the value of the so-called Child-Langmuir sheath.

  19. Characterization of Cestrum yellow leaf curling virus: a new member of the family Caulimoviridae.

    Science.gov (United States)

    Stavolone, Livia; Ragozzino, Antonio; Hohn, Thomas

    2003-12-01

    Cestrum yellow leaf curling virus (CmYLCV) has been characterized as the aetiological agent of the Cestrum parqui mosaic disease. The virus genome was cloned and the clone was proven to be infectious to C. parqui. The presence of typical viroplasms in virus-infected plant tissue and the information obtained from the complete genomic sequence confirmed CmYLCV as a member of the Caulimoviridae family. All characteristic domains conserved in plant pararetroviruses were found in CmYLCV. Its genome is 8253 bp long and contains seven open reading frames (ORFs). Phylogenetic analysis of the relationships with other members of the Caulimoviridae revealed that CmYLCV is closely related to the Soybean chlorotic mottle virus (SbCMV)-like genus and particularly to SbCMV. However, in contrast to the other members of this genus, the primer-binding site is located in the intercistronic region following ORF Ib rather than within this ORF, and an ORF corresponding to ORF VII is missing.

  20. Detection of tomato yellow leaf curl Thailand virus by PCR without DNA extraction.

    Science.gov (United States)

    Ieamkhang, Supaporn; Riangwong, Lumpueng; Chatchawankanphanich, Orawan

    2005-11-01

    We report the simple and rapid method for detection of tomato yellow leaf curl Thailand virus (TYLCTHV) based on the direct capture of virus particles to the surface of a polymerase chain reaction (PCR) tube. This method allowed PCR without the time-consuming procedures of DNA extraction from infected plant tissue. A small amount of tomato tissue (approximately 10 mg) was ground in extraction buffer to release viruses from plant tissues. The constituents of the plant extract that might inhibit PCR activity were discarded by washing the tube with PBST buffer before adding the PCR mixture to the tube. This method was used for detection of TYLCTHV with plant sap solution diluted up to 1:20,000 and was more sensitive than an enzyme-linked immunosorbent assay (ELISA) method. In addition, this method can be used for detection of TYLCTHV in viruliferous whiteflies. The PCR tubes with captured TYLCTHV could be used for PCR, after storage at 4 degrees C for 4 wk. The method presented here was used for detection of begomoviruses in cucurbit and pepper. In addition, this method was effectively used to detect papaya ringspot virus in papaya and zucchini yellow mosaic virus in cucumber by reverse transcriptase (RT)-PCR.

  1. Curl flux induced drift in stochastic differential equations in the zero-mass limit

    Science.gov (United States)

    Wang, Jinhua; Yuan, Bo

    2016-11-01

    We consider the nonlinear stochastic dynamics of dissipative Hamiltonian systems with state-dependent friction and diffusion connected by the fluctuation-dissipation relation in high dimensions. The system under study has a close connection to Ao's framework in constructing a dynamical potential for non-equilibrium processes without detailed balance. We study the limiting case where the mass approaches zero and give a new and complete derivation of effective stochastic differential equations. Using the Ito stochastic integral convention, we show that the limiting effective Langevin equations have a new drift term. This extra term happens to be identical to the corresponding anti-Ito (or isothermal) integral (requiring constant temperature) in one dimension. We, however, cannot obtain this additional drift term using conventional stochastic integrals in high dimension. It is interesting to note that in a high-dimensional system, a curl flux induced drift may appear even if the diffusion matrix is constant. Our findings are supported by numerical simulations. We further analyze and discuss the role of this new drift term in calculating the classic escape time. For the first time, to our knowledge, the relation between the escape rate and the anti-Ito integral is presented. We also demonstrate that the derived diffusion equations give a new sampling algorithm which can increase convergence speed in a simple two-dimensional example.

  2. The Involvement of Heat Shock Proteins in the Establishment of Tomato Yellow Leaf Curl Virus Infection

    Science.gov (United States)

    Gorovits, Rena; Czosnek, Henryk

    2017-01-01

    Tomato yellow leaf curl virus (TYLCV), a begomovirus, induces protein aggregation in infected tomatoes and in its whitefly vector Bemisia tabaci. The interactions between TYLCV and HSP70 and HSP90 in plants and vectors are necessity for virus infection to proceed. In infected host cells, HSP70 and HSP90 are redistributed from a soluble to an aggregated state. These aggregates contain, together with viral DNA/proteins and virions, HSPs and components of the protein quality control system such as ubiquitin, 26S proteasome subunits, and the autophagy protein ATG8. TYLCV CP can form complexes with HSPs in tomato and whitefly. Nonetheless, HSP70 and HSP90 play different roles in the viral cell cycle in the plant host. In the infected host cell, HSP70, but not HSP90, participates in the translocation of CP from the cytoplasm into the nucleus. Viral amounts decrease when HSP70 is inhibited, but increase when HSP90 is downregulated. In the whitefly vector, HSP70 impairs the circulative transmission of TYLCV; its inhibition increases transmission. Hence, the efficiency of virus acquisition by whiteflies depends on the functionality of both plant chaperones and their cross-talk with other protein mechanisms controlling virus-induced aggregation.

  3. Tomato Leaf Curl New Delhi Virus: An Emerging Virus Complex Threatening Vegetable and Fiber Crops

    Directory of Open Access Journals (Sweden)

    Enrique Moriones

    2017-09-01

    Full Text Available The tomato leaf curl New Delhi virus (ToLCNDV (genus Begomovirus, family Geminiviridae represents an important constraint to tomato production, as it causes the most predominant and economically important disease affecting tomato in the Indian sub-continent. However, in recent years, ToLCNDV has been fast extending its host range and spreading to new geographical regions, including the Middle East and the western Mediterranean Basin. Extensive research on the genome structure, protein functions, molecular biology, and plant–virus interactions of ToLCNDV has been conducted in the last decade. Special emphasis has been given to gene silencing suppression ability in order to counteract host plant defense responses. The importance of the interaction with DNA alphasatellites and betasatellites in the biology of the virus has been demonstrated. ToLCNDV genetic variability has been analyzed, providing new insights into the taxonomy, host adaptation, and evolution of this virus. Recombination and pseudorecombination have been shown as motors of diversification and adaptive evolution. Important progress has also been made in control strategies to reduce disease damage. This review highlights these various achievements in the context of the previous knowledge of begomoviruses and their interactions with plants.

  4. Tomato Leaf Curl New Delhi Virus: An Emerging Virus Complex Threatening Vegetable and Fiber Crops.

    Science.gov (United States)

    Moriones, Enrique; Praveen, Shelly; Chakraborty, Supriya

    2017-09-21

    The tomato leaf curl New Delhi virus (ToLCNDV) (genus Begomovirus, family Geminiviridae) represents an important constraint to tomato production, as it causes the most predominant and economically important disease affecting tomato in the Indian sub-continent. However, in recent years, ToLCNDV has been fast extending its host range and spreading to new geographical regions, including the Middle East and the western Mediterranean Basin. Extensive research on the genome structure, protein functions, molecular biology, and plant-virus interactions of ToLCNDV has been conducted in the last decade. Special emphasis has been given to gene silencing suppression ability in order to counteract host plant defense responses. The importance of the interaction with DNA alphasatellites and betasatellites in the biology of the virus has been demonstrated. ToLCNDV genetic variability has been analyzed, providing new insights into the taxonomy, host adaptation, and evolution of this virus. Recombination and pseudorecombination have been shown as motors of diversification and adaptive evolution. Important progress has also been made in control strategies to reduce disease damage. This review highlights these various achievements in the context of the previous knowledge of begomoviruses and their interactions with plants.

  5. Inhibition of Tomato Yellow Leaf Curl Virus (TYLCV using whey proteins

    Directory of Open Access Journals (Sweden)

    Dawood Abdelgawad

    2010-02-01

    Full Text Available Abstract The antiviral activity of native and esterified whey proteins fractions (α-lactalbumin, β-lactoglobulin, and lactoferrin was studied to inhibit tomato yellow leaf curl virus (TYLCV on infected tomato plants. Whey proteins fractions and their esterified derivatives were sprayed into TYLCV-infected plants. Samples were collected from infected leaves before treatment, 7 and 15 days after treatment for DNA and molecular hybridization analysis. The most evident inhibition of virus replication was observed after 7 and 15 days using α-lactoferrin and α-lactalbumin, respectively. Native and esterified lactoferrin showed complete inhibition after 7 days. On the other hand, native β-lactoglobulin showed inhibition after 7 and 15 days whereas esterified β-lactoglobulin was comparatively more effective after 7 days. The relative amount of viral DNA was less affected by the esterified α-lactalbumin whereas native α-lactalbumin inhibited virus replication completely after 15 days. These results indicate that native or modified whey proteins fractions can be used for controlling the TYLCV-infected plants.

  6. Rapid detection of squash leaf curl virus by loop-mediated isothermal amplification.

    Science.gov (United States)

    Kuan, Cheng-Ping; Wu, Min-Tze; Lu, Yi-Lin; Huang, Hung-Chang

    2010-10-01

    A loop-mediated isothermal amplification (LAMP) assay was employed to develop a simple and efficient system for the detection of squash leaf curl virus (SLCV) in diseased plants of squash (Cucurbita pepo) and melon (Cucumis melo). Completion of LAMP assay required 30-60 min under isothermal conditions at 65 degrees C by employing a set of four primers targeting SLCV. Although the sensitivity of the LAMP assay and the polymerase chain reaction (PCR) assay was comparable at high virus concentrations, the LAMP assay was by a 10-fold dilution factor more sensitive than the PCR assay for the detection of SLCV in diseased plants. No reaction was detected in the tissues of healthy plants by either the LAMP or the PCR. The LAMP products can be visualized by staining directly in the tube with SYBR Safe DNA gel stain dye. The sensitivity of the SYBR Safe DNA gel stain is similar to analysis by gel electrophoresis. Although both the LAMP and the PCR methods were capable of detecting SLCV in infected tissues of squash and melon, the LAMP method would be more useful than the PCR method for detection of SLCV infection in cucurbitaceous plants because it is more rapid, simple, accurate and sensitive.

  7. FUNCTIONAL AND NEUROMUSCULAR CHANGES IN THE HAMSTRINGS AFTER DROP JUMPS AND LEG CURLS

    Directory of Open Access Journals (Sweden)

    Nejc Sarabon

    2013-09-01

    Full Text Available The purpose of this study was to use a holistic approach to investigate changes in jumping performance, kinaesthesia, static balance, isometric strength and fast stepping on spot during a 5-day recovery period, following an acute bout of damaging exercise consisted of drop jumps and leg curls, where specific emphasis was given on the hamstring muscles. Eleven young healthy subjects completed a series of highly intensive damaging exercises for their hamstring muscles. Prior to the exercise, and during the 5-day recovery period, the subjects were tested for biochemical markers (creatine kinase, aspartate aminotransferase, and lactate dehydrogenase, perceived pain sensation, physical performance (squat jump, counter movement jump, maximal frequency leg stamping, maximal isometric torque production and maximally explosive isometric torque production, kinaesthesia (active torque tracking and static balance. We observed significant decreases in maximal isometric knee flexion torque production, the rate of torque production, and majority of the parameters for vertical jump performance. No alterations were found in kinaesthesia, static balance and fast stepping on spot. The highest drop in performance and increase in perceived pain sensation generally occurred 24 or 48 hours after the exercise. Damaging exercise substantially alters the neuromuscular functions of the hamstring muscles, which is specifically relevant for sports and rehabilitation experts, as the hamstrings are often stretched to significant lengths, in particular when the knee is extended and hip flexed. These findings are practically important for recovery after high-intensity trainings for hamstring muscles

  8. Overproduction of superoxide dismutase and catalase confers cassava resistance to Tetranychus cinnabarinus.

    Science.gov (United States)

    Lu, Fuping; Liang, Xiao; Lu, Hui; Li, Qian; Chen, Qing; Zhang, Peng; Li, Kaimian; Liu, Guanghua; Yan, Wei; Song, Jiming; Duan, Chunfang; Zhang, Linhui

    2017-01-05

    To explore the role of protective enzymes in cassava (Manihot esculenta Crantz) resistance to mites, transgenic cassava lines overproducing copper/zinc superoxide dismutase (MeCu/ZnSOD) and catalase (MeCAT1) were used to evaluate and molecularly confirm cassava resistance to Tetranychus cinnabarinus. Laboratory evaluation demonstrated that, compared with the control cultivar TMS60444 (wild type, WT), the survival, reproduction, development and activities of SOD and CAT in T. cinnabarinus feeding on transgenic cassava lines SC2, SC4, and SC11 significantly inhibited. Furthermore, the activities of SOD and CAT in transgenic cassava lines SC2, SC4, and SC11 damaged by T. cinnabarinus significantly increased. These findings were similar to the results in the mite-resistant cassava cultivars. Besides, field evaluation indicated that the transgenic cassava lines SC2, SC4, and SC11 were slightly damaged as the highly mite-resistant control C1115, while the highly mite-susceptible WT was severely damaged by T. cinnabarinus. Laboratory and field evaluation demonstrated that transgenic cassava lines were resistant to T. cinnabarinus, which directly confirmed that the increase in SOD and CAT activities was positively related to cassava resistance to T. cinnabarinus. These results will help in understanding the antioxidant defense responses in the cassava-mite interaction and molecular breeding of mite-resistant cassava for effective pest control.

  9. Dry Dog Food Integrity and Mite Strain Influence the Density-Dependent Growth of the Stored-Product Mite Tyrophagus putrescentiae (Acari: Acaridida).

    Science.gov (United States)

    Rybanska, Dagmar; Hubert, Jan; Markovic, Martin; Erban, Tomas

    2016-02-01

    The infestation of foodstuffs by mites is connected to health risks and economic losses. The cosmopolitan stored-product mite Tyrophagus putrescentiae (Schrank, 1781) is an emerging and predominant pest of dry dog food. In this study, the influences on mite population growth of 1) the different dry dog food kernels present in the package; 2) the integrity of the dry dog food kernel, whether intact or crushed; 3) the initial population density of 10 or 100 specimens; and 4) the four mite strains used were investigated under laboratory conditions. The population growth tests were performed for 28 d at 85% relative humidity and 25°C. The intrinsic growth rates of the mites were compared. The population growth was higher on the brown and green kernels than on the red and white kernels. The kernel integrity affected the population growth, and the integrity effect was highly influenced by the initial mite population density. The mites showed density-dependent growth in three of the four mite strains tested. The initial population density changed the population growth ranking among the mite strains, thereby indicating strain-specific density-dependent growth. The results of this study have important implications for predictive models of stored-product mite populations in dry dog food. One practical recommendation is that the growth of mites should be considered with regard to the mite strains and according to the strain-specific density dependent growth. Next, the integrity of the kernels should be maintained because disrupted or crushed kernels promote increases in mite populations.

  10. Candidate predators for biological control of the poultry red mite Dermanyssus gallinae

    NARCIS (Netherlands)

    Lesna, Izabela; Wolfs, Peter; Faraji, Farid; Roy, Lise; Komdeur, Jan; Sabelis, Maurice W.

    2009-01-01

    The poultry red mite, Dermanyssus gallinae, is currently a significant pest in the poultry industry in Europe. Biological control by the introduction of predatory mites is one of the various options for controlling poultry red mites. Here, we present the first results of an attempt to identify poten

  11. Laboratory evaluation of the effect of inert dust formulations on the poultry red mite, Dermanyssus gallinae

    DEFF Research Database (Denmark)

    Kilpinen, Ole; Steenberg, Tove

    In the EU-project SAFEHOUSE one objective is to develop alternative control methods against poultry red mites based on a combination of inert dusts and mite-pathogenic fungal isolates. Both components have some pathogenicity to the mites. However, the question is whether a combination of the two ...

  12. Heritability of defence and life-history traits in the two-spotted spider mite

    NARCIS (Netherlands)

    Tien, N.S.H.; Sabelis, M.W.; Egas, M.

    2009-01-01

    Background: Two-spotted spider mites hide against predatory mites in a web of self-produced sticky silk. The proteins invested in this shelter may reduce investment in reproduction. Questions: Do spider mite populations harbor genetic variation for web production, thereby enabling a response to

  13. Are Demodex mites principal, conspirator, accomplice, witness or bystander in the cause of rosacea?

    Science.gov (United States)

    Chen, WenChieh; Plewig, Gerd

    2015-04-01

    As the only permanent human ectoparasite, the role of human Demodex mites in health and diseases remains largely unclarified. In view of the ecological interaction between organisms of two different species, a type of commensalism between Demodex mites and humans (the former benefit, the latter unaffected) is most likely, while parasitism occurs temporarily and spatially in the diseased state (the former benefit, the latter harmed). As part of normal skin microbiota, the causal role of Demodex mites in the initiation of rosacea can neither fulfill the classical Henle-Koch's principal nor the advanced criteria proposed by Fredericks and Relman for molecular detection of non-cultivatable microorganisms. Epidemiological analysis using Hill's criteria fails to support the causative role of Demodex mites in rosacea regarding the strength of association, specificity and temporality of association, biological gradient and plausibility as well as clinical coherence, therapeutic experimentation and medical analogy. In application of Rothman's sufficient cause model to evaluate the contribution of Demodex mites to rosacea on a population basis, Demodex mites can be regarded as a non-necessary, non-sufficient causal factor for certain forms of rosacea. Further strategies to dissect the association between Demodex mites and rosacea may include studying the possible existence of more virulent forms of mites with a higher pathogenicity, the endosymbiotic bacteria in certain life periods of mites, the interactions between mites and human hosts or between mites and environment, and to set up ex vivo culture models for Demodex mites.

  14. [Ecological data on house dust mites in the city of Semipalatinsk].

    Science.gov (United States)

    Iagofarov, F F; Galikeev, Kh L

    1987-01-01

    Distribution of mites of the genus Dermatophagoides in flats of allergic patients depending on the type of the building structure, relative air humidity and season of the year was studied. The mites are most frequently encountered in houses of wood or adobe with high air humidity. Autumn is an optimum season for reproduction of mites.

  15. Heritability of defence and life-history traits in the two-spotted spider mite

    NARCIS (Netherlands)

    Tien, N.S.H.; Sabelis, M.W.; Egas, M.

    2009-01-01

    Background: Two-spotted spider mites hide against predatory mites in a web of self-produced sticky silk. The proteins invested in this shelter may reduce investment in reproduction. Questions: Do spider mite populations harbor genetic variation for web production, thereby enabling a response to sele

  16. Ligand selectivity in tachykinin and natalisin neuropeptidergic systems of the honey bee parasitic mite Varroa destructor

    Science.gov (United States)

    The varroa mite, Varroa destructor, is a devastating ectoparasite of the honey bees Apis mellifera and A. cerana. Control of these mites in beehives is a challenge in part due to the lack of toxic agents that are specific to mites and not to the host honey bee. In searching for a specific toxic targ...

  17. A review of the water mite fauna from the Australasian and Pacific region (Acari: Hydrachnidia)

    NARCIS (Netherlands)

    Smit, H.

    2005-01-01

    A review is given of the water mite fauna of the Australasian and Pacific region. Within the Australasian region, New Zealand has the highest percentage of endemism. It is concluded that the water mite fauna of the islands in the South Pacific is of Australasian origin, while the water mite fauna of

  18. Morphology of the olfactory system in the predatory mite Phytoseiulus persimilis

    NARCIS (Netherlands)

    M. van Wijk; W.J. Wadman; M.W. Sabelis

    2006-01-01

    The predatory mite Phytoseiulus persimilis locates its prey, the two-spotted spider mite, by means of herbivore-induced plant volatiles. The olfactory response to this quantitatively and qualitatively variable source of information is particularly well documented. The mites perform this task with a

  19. Dermatitis due to Mixed Demodex and Sarcoptes Mites in Dogs

    Directory of Open Access Journals (Sweden)

    B. Sudhakara Reddy

    2014-01-01

    Full Text Available In dogs, dermatitis due to mixed mite infestation is rare. During the five-year period of study, two dogs were identified suffering from dermatitis due to mixed Demodex and Sarcoptes mites. Upon clinical examination dogs had primary and secondary skin lesions on face, around the ears, chin, neck, fore limbs and lateral abdomen. Microscopic examination of skin scrapings revealed Demodex and Sarcoptes mites. Both dogs were treated with daily oral ivermectin at 100 to 400 μg/kg body weight as incremental doses, external application of amitraz and supportive treatments with topical antimicrobial shampoo. After completion of forty-two days of therapy, dogs were recovered from the dermatitis.

  20. Quill mites in Brazilian psittacine birds (Aves: Psittaciformes).

    Science.gov (United States)

    Jardim, Cassius Catão Gomes; Cunha, Lucas Maciel; Rezende, Leandro do Carmo; Teixeira, Cristina Mara; Martins, Nelson Rodrigo da Silva; de Oliveira, Paulo Roberto; Leite, Romário Cerqueira; Faccini, João Luiz Horácio; Leite, Rômulo Cerqueira

    2012-09-01

    The primary and secondary feathers of 170 Brazilian psittacine birds (Aves: Psittaciformes) were examined in order to identify feather quill mite fauna. Birds were held captive in two locations in the state of Minas Gerais (MG), and two in the state of Espirito Santo (ES). The quills were cut longitudinally and were examined under optical microscopy. The genus of quill mites most frequently found was Paralgopsis (Astigmata: Pyrogliphidae), followed by Cystoidosoma (Astigmata: Syringobiidae). Astigmata: Syringophilidae mites were sporadically observed. After analyzing the data using logistic regression models, it was determined that there was higher infestation risk for psittacines in ES state, as compared with those in MG, and a significant increase in risk depending on the psittacine host species. However, the location of captivity did not have a significant effect. Lesions were observed in infested feathers. Cystoidosoma sp. and Paralgopsis sp. were always observed together, with parts of Paralgopsis found inside Cystoidosoma sp., suggesting thanatochresis or predation.

  1. mites y control constitucional en México

    Directory of Open Access Journals (Sweden)

    Arminda Balbuena Cisneros

    2007-01-01

    Full Text Available Los límites a la reforma constitucional es un tema siempre vigente en el derecho constitucional, ello es así por las posibles arbitrariedades que pueden cometer los órganos detentadores del poder mediante las modificaciones a la constitución. En México, hoy en día este tema cobra particular relevancia por el profundo proceso de reforma que se vive, y por la controvertida posición que la corte mexicana ha adoptado en relación con los límites a la reforma. El presente artículo trata de dar una visión general de los límites al poder de reforma y, en particular, de la posición que la suprema corte de justicia de la nación ha adoptado respecto a los mismos.

  2. Global divergence of the human follicle mite Demodex folliculorum

    DEFF Research Database (Denmark)

    Palopoli, Michael F.; Fergus, Daniel J.; Minot, Samuel

    2015-01-01

    Microscopic mites of the genus Demodex live within the hair follicles of mammals and are ubiquitous symbionts of humans, but little molecular work has been done to understand their genetic diversity or transmission. Here we sampled mite DNA from 70 human hosts of diverse geographic ancestries...... American ancestry. To a great extent, the ancestral geography of hosts predicted the lineages of mites found on them; 27% of the total molecular variance segregated according to the regional ancestries of hosts. We found that D. folliculorum populations are stable on an individual over the course of years......, indicating that transmission requires close contact. Dating analyses indicated that D. folliculorum origins may predate modern humans. Overall, D. folliculorum evolution reflects ancient human population divergences, is consistent with an out-of-Africa dispersal hypothesis, and presents an excellent model...

  3. Environmental Engineering Approaches toward Sustainable Management of Spider Mites.

    Science.gov (United States)

    Suzuki, Takeshi

    2012-10-26

    Integrated pest management (IPM), which combines physical, biological, and chemical control measures to complementary effect, is one of the most important approaches to environmentally friendly sustainable agriculture. To expand IPM, we need to develop new pest control measures, reinforce existing measures, and investigate interactions between measures. Continued progress in the development of environmental control technologies and consequent price drops have facilitated their integration into plant production and pest control. Here I describe environmental control technologies for the IPM of spider mites through: (1) the disturbance of photoperiod-dependent diapause by artificial light, which may lead to death in seasonal environments; (2) the use of ultraviolet radiation to kill or repel mites; and (3) the use of water vapor control for the long-term cold storage of commercially available natural enemies. Such environmental control technologies have great potential for the efficient control of spider mites through direct physical effects and indirect effects via natural enemies.

  4. Environmental Engineering Approaches toward Sustainable Management of Spider Mites

    Directory of Open Access Journals (Sweden)

    Takeshi Suzuki

    2012-10-01

    Full Text Available Integrated pest management (IPM, which combines physical, biological, and chemical control measures to complementary effect, is one of the most important approaches to environmentally friendly sustainable agriculture. To expand IPM, we need to develop new pest control measures, reinforce existing measures, and investigate interactions between measures. Continued progress in the development of environmental control technologies and consequent price drops have facilitated their integration into plant production and pest control. Here I describe environmental control technologies for the IPM of spider mites through: (1 the disturbance of photoperiod-dependent diapause by artificial light, which may lead to death in seasonal environments; (2 the use of ultraviolet radiation to kill or repel mites; and (3 the use of water vapor control for the long-term cold storage of commercially available natural enemies. Such environmental control technologies have great potential for the efficient control of spider mites through direct physical effects and indirect effects via natural enemies.

  5. Curl flux, coherence, and population landscape of molecular systems: Nonequilibrium quantum steady state, energy (charge) transport, and thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z. D. [Department of Physics and Astronomy, SUNY Stony Brook, New York 11794 (United States); Wang, J. [Department of Physics and Astronomy, SUNY Stony Brook, New York 11794 (United States); Department of Chemistry, SUNY Stony Brook, New York 11794 (United States); State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022 (China)

    2014-06-28

    We established a theoretical framework in terms of the curl flux, population landscape, and coherence for non-equilibrium quantum systems at steady state, through exploring the energy and charge transport in molecular processes. The curl quantum flux plays the key role in determining transport properties and the system reaches equilibrium when flux vanishes. The novel curl quantum flux reflects the degree of non-equilibriumness and the time-irreversibility. We found an analytical expression for the quantum flux and its relationship to the environmental pumping (non-equilibriumness quantified by the voltage away from the equilibrium) and the quantum tunneling. Furthermore, we investigated another quantum signature, the coherence, quantitatively measured by the non-zero off diagonal element of the density matrix. Populations of states give the probabilities of individual states and therefore quantify the population landscape. Both curl flux and coherence depend on steady state population landscape. Besides the environment-assistance which can give dramatic enhancement of coherence and quantum flux with high voltage at a fixed tunneling strength, the quantum flux is promoted by the coherence in the regime of small tunneling while reduced by the coherence in the regime of large tunneling, due to the non-monotonic relationship between the coherence and tunneling. This is in contrast to the previously found linear relationship. For the systems coupled to bosonic (photonic and phononic) reservoirs the flux is significantly promoted at large voltage while for fermionic (electronic) reservoirs the flux reaches a saturation after a significant enhancement at large voltage due to the Pauli exclusion principle. In view of the system as a quantum heat engine, we studied the non-equilibrium thermodynamics and established the analytical connections of curl quantum flux to the transport quantities such as energy (charge) transfer efficiency, chemical reaction efficiency, energy

  6. Investigations on the Effects of Five Different Plant Extracts on the Two-Spotted Mite Tetranychus urticae Koch (Arachnida: Tetranychidae

    Directory of Open Access Journals (Sweden)

    Pervin Erdogan

    2012-01-01

    Full Text Available Two-spotted mite, Tetranychus urticae Koch (Arac.: Tetranychidae, is an economic pest worldwide including Turkey, causing serious damage to vegetables, flowers, and fruit crops. In recent years, broad-spectrum insecticides/miticides have been used to control this pest in Turkey. Control is difficult mainly due to resistance to conventional pesticides. This study was conducted to determine efficacy of pesticides extracted from five different plants [i.e., Allium sativum L. (Amaryllidaceae, Rhododendron luteum S. (Ericaceae, Helichrysum arenarium L. (Asteraceae, Veratrum album L. (Liliaceae, and Tanacetum parthenium L. (Asteraceae] against this mite. Bioassays were tested by two different methods to determine the effects of varying concentrations. Experiments were performed using 3 cm diameter leaf disk from unsprayed bean plants (Phaseolus vulgaris L.. In addition, the effects of the extracts on reproduction and oviposition were investigated. The extract yielded high mortality. In the lowest-concentration bioassays, the adult mites laid lower numbers of eggs compared to the untreated control. No ovicidal effect was observed.

  7. Effects of Nitrogen Fertilization on Potato Leafhopper (Hemiptera: Cicadellidae) and Maple Spider Mite (Acari: Tetranychidae) on Nursery-Grown Maples.

    Science.gov (United States)

    Prado, Julia; Quesada, Carlos; Gosney, Michael; Mickelbart, Michael V; Sadof, Clifford

    2015-06-01

    Although leaf nitrogen (N) has been shown to increase the suitability of hosts to herbivorous arthropods, the responses of these pests to N fertilization on susceptible and resistant host plants are not well characterized. This study determined how different rates of N fertilization affected injury caused by the potato leafhopper (Empoasca fabae Harris) and the abundance of maple spider mite (Oligonychus aceris (Shimer)) on 'Red Sunset' red maple (Acer rubrum) and 'Autumn Blaze' Freeman maple (Acer×freemanii) during two years in Indiana. N fertilization increased leaf N concentration in both maple cultivars, albeit to a lesser extent during the second year of the study. Overall, Red Sunset maples were more susceptible to E. fabae injury than Autumn Blaze, whereas Autumn Blaze maples supported higher populations of O. aceris. Differences in populations of O. aceris were attributed to differences between communities of stigmaeid and phytoseiid mites on each cultivar. Injury caused by E. fabae increased with N fertilization in a dose-dependent manner in both cultivars. Although N fertilization increased the abundance of O. aceris on both maple cultivars, there was no difference between the 20 and 40 g rates. We suggest the capacity of N fertilization to increase O. aceris on maples could be limited at higher trophic levels by the community of predatory mites.

  8. Host finding behaviour of the coconut mite Aceria guerreronis.

    Science.gov (United States)

    Melo, J W S; Lima, D B; Sabelis, M W; Pallini, A; Gondim, M G C

    2014-12-01

    For the coconut mite, Aceria guerreronis Keifer, its host plant, the coconut palm, is not merely a source of food, but more generally a habitat to live in for several generations. For these minute organisms, finding a new plant is difficult and risky, especially because their main mode of dispersal is passive drifting with the wind and because they are highly specialized on their host plant. Consequently, the probability of landing on a suitable host is very low, let alone to land in their specific microhabitat within the host. How coconut mites manage to find their microhabitat within a host plant is still underexplored. We tested the hypothesis that they use volatile chemical information emanating from the plant to find a specific site within their host plants and/or use non-volatile plant chemicals to stay at a profitable site on the plant. This was investigated in a Y-tube olfactometer (i.e. under conditions of a directed wind flow) and on cross-shaped arenas (i.e. under conditions of turbulent air) that either allowed contact with odour sources or not. The mites had to choose between odours from specific parts (leaflet, spikelet or fruit) of a non-infested coconut plant and clean air as the alternative. In the olfactometer experiments, no mites were found to reach the upwind end of the Y-tube: coconut mites was found only when the arm of the arena contained discs of fruit epidermis and contact with these discs was allowed. The results suggest that coconut mites on palm trees are not attracted to specific sites on the plant by volatile plant chemicals, but that they arrested once they contact the substrate of specific sites. Possibly, they perceive non-volatile chemicals, but these remain to be identified.

  9. Under the lash: Demodex mites in human diseases.

    Science.gov (United States)

    Lacey, Noreen; Kavanagh, Kevin; Tseng, Scheffer C G

    2009-08-01

    Demodex mites, class Arachnida and subclass Acarina, are elongated mites with clear cephalothorax and abdomens, the former with four pairs of legs. There are more than 100 species of Demodex mite, many of which are obligatory commensals of the pilosebaceous unit of mammals including cats, dogs, sheep, cattle, pigs, goats, deer, bats, hamsters, rats and mice. Among them, Demodex canis, which is found ubiquitously in dogs, is the most documented and investigated. In excessive numbers D. canis causes the inflammatory disease termed demodicosis (demodectic mange, follicular mange or red mange), which is more common in purebred dogs and has a hereditary predisposition in breeding kennels1. Two distinct Demodex species have been confirmed as the most common ectoparasite in man. The larger Demodex folliculorum, about 0.3-0.4 mm long, is primarily found as a cluster in the hair follicle (Figure 1a), while the smaller Demodex brevis, about 0.2-0.3 mm long with a spindle shape and stubby legs, resides solitarily in the sebaceous gland (Figure 1b). These two species are also ubiquitously found in all human races without gender preference. The pathogenic role of Demodex mites in veterinary medicine is not as greatly disputed as in human diseases. In this article, we review the key literature and our joint research experience regarding the pathogenic potential of these two mites in causing inflammatory diseases of human skin and eye. We hope that the evidence summarized herein will invite readers to take a different look at the life of Demodex mites in several common human diseases.

  10. Transcriptional responses in eastern honeybees (Apis cerana) infected with mites, Varroa destructor.

    Science.gov (United States)

    Ji, T; Yin, L; Liu, Z; Liang, Q; Luo, Y; Shen, J; Shen, F

    2014-10-31

    The Varroa destructor mite has become the greatest threat to Apis mellifera health worldwide, but rarely causes serious damage to its native host Apis cerana. Understanding the resistance mechanisms of eastern bees against Varroa mites will help researchers determine how to protect other species from this organism. The A. cerana genome has not been previously sequenced; hence, here we sequenced the A. cerana nurse workers transcriptome and monitored the differential gene expression of A. cerana bees challenged by V. destructor. Using de novo transcriptome assembly, we obtained 91,172 unigenes (transcripts) for A. cerana. Differences in gene expression levels between the unchallenged (Con) and challenged (Con2) samples were estimated, and a total of 36,691 transcripts showed a 2-fold difference (at least) between the 2 libraries. A total of 272 differentially expressed genes showed differences greater than 15-fold, and 265 unigenes were present at higher levels in Con2 than in Con. Among the upregulated unigenes in the Con2 colony, genes related to skeletal muscle movement (troponin and calcium-transporting ATPase), olfactory sensitivity (odorant binding proteins, and Down syndrome cell adhesion molecule gene) and transcription factors (cyclic adenosine monophosphate-responsive element-binding protein and transcription factor mblk-1) appeared to be involved in Varroa resistance. Real-time polymerase chain reaction was performed to validate these differentially expressed genes screened by the sequencing approach, and sufficient consistency was observed between the two methods. These findings strongly support that hygienic and grooming behaviors play important roles in Varroa resistance.

  11. Mite antigen and allergen contents of house dust samples.

    Directory of Open Access Journals (Sweden)

    Ishii,Akira

    1988-02-01

    Full Text Available The house dust mite (Dermatophagoides pteronyssinus antigen and allergen contents were measured by enzyme-linked immunosorbent assay (ELISA with enzyme-labelled anti-human IgE and anti-mite rabbit IgG antibodies. Antigen content was high in dust samples from homes of patients with allergy but not in samples from homes of patients with Kawasaki disease or of normal control subjects. Allergen content was high in dust samples from homes of Kawasaki disease patients. However, the values overlapped, and we considered these differences to be of little ecological significance, although the assay method itself is useful.

  12. Ciclos límites en minirobots neurocontrolados

    OpenAIRE

    Jesús Alberto Delgado

    2011-01-01

    Este artículo presenta el análisis de estabilidad de un pequeño robot controlado con una red neuronal multicapa; por simplicidad, el robot contiene un sensor de posición y un motor. La función descriptiva de la red neuronal se utiliza para determinar los límites para los pesos de la red, con el fin de predecir ciclos límite y evitar oscilaciones del minirobot cuando se aproxima a obstáculos.

  13. OZONE: ALTERNATIVE METHOD FOR MITE CONTROL ON SPECK

    Directory of Open Access Journals (Sweden)

    C. Cantoni

    2013-02-01

    Full Text Available This study is aimed at the development of a method for integrated mite control in the industrial production of speck. The investigation were carried out on the premises of five factories in the north-east of Italy. Tyrophagus putrescentiae and T. longior were predominant. The gaseous ozone treatment at low level (0.4 ppm was able to kill mites in a period within 15 days and 1 month. The characteristic layer of mould on the product surface reappears within 1 month from the end of treatment with ozone.

  14. Asynchronous development of honey bee host and Varroa destructor (Mesostigmata: Varroidae) influences reproductive potential of mites.

    Science.gov (United States)

    Kirrane, Maria J; De Guzman, Lilia I; Rinderer, Thomas E; Frake, Amanda M; Wagnitz, Jeremy; Whelan, Pádraig M

    2011-08-01

    A high proportion of nonreproductive (NR) Varroa destructor Anderson & Trueman (Mesostigmata: Varroidae), is commonly observed in honey bee colonies displaying the varroa sensitive hygienic trait (VSH). This study was conducted to determine the influence of brood removal and subsequent host reinvasion of varroa mites on mite reproduction. We collected foundress mites from stages of brood (newly sealed larvae, prepupae, white-eyed pupae, and pink-eyed pupae) and phoretic mites from adult bees. We then inoculated these mites into cells containing newly sealed larvae. Successful reproduction (foundress laid both a mature male and female) was low (13%) but most common in mites coming from sealed larvae. Unsuccessful reproductive attempts (foundress failed to produce both a mature male and female) were most common in mites from sealed larvae (22%) and prepupae (61%). Lack of any progeny was most common for mites from white-eyed (83%) and pink-eyed pupae (92%). We also collected foundress mites from sealed larvae and transferred them to cells containing newly sealed larvae, prepupae, white-eyed pupae, or pink-eyed pupae. Successful reproduction only occurred in the transfers to sealed larvae (26%). Unsuccessful reproductive attempts were most common in transfers to newly sealed larvae (40%) and to prepupae (25%). Unsuccessful attempts involved the production of immature progeny (60%), the production of only mature daughters (26%) or the production of only a mature male (14%). Generally, lack of progeny was not associated with mites having a lack of stored sperm. Our results suggest that mites exposed to the removal of prepupae or older brood due to hygiene are unlikely to produce viable mites if they invade new hosts soon after brood removal. Asynchrony between the reproductive status of reinvading mites and the developmental stage of their reinvasion hosts may be a primary cause of NR mites in hygienic colonies. Even if reinvading mites use hosts having the proper age

  15. Improvement of shrimp allergy after sublingual immunotherapy for house dust mites: a case report.

    Science.gov (United States)

    Cortellini, G; Spadolini, I; Santucci, A; Cova, V; Conti, C; Corvetta, A; Passalacqua, G

    2011-10-01

    The appropriateness of house dust mite specific immunotherapy in patients allergic to shrimps still remains unclear We present a clinical case as an immunological model for the strong sensitization to tropomyosin with symptoms of anaphylaxis due to shrimps and coexisting asthma due to house dust mite. The improvement in respiratory symptoms for house dust mite and in the food challenge for shrimps during mite immunotherapy with a known and high dosage of tropomyosin suggests the hypothesis that efficacy of mite immunotherapy in food allergy to tropomyosin may be dose dependent.

  16. Deletional analysis of functional regions of complementary sense promoter from cotton leaf curl virus

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Complementary sense promoter from cotton leaf curl virus (CLCuV) is a novel plant promoter for genetic engineering that could drive high-level foreign gene expression in plant. To determine the optimal promoter sequence for gene expression, CLCuV promoter was deleted from its 5' end to form promoter fragments with five different lengths, and chimeric gus genes were constructed using the promoter deletion. These vectors were delivered into Agrobacterium and tobacco (Nicotiana tabacum L. cv. Xanthi) plants which were transformed by leaf discs method. GUS activity of transgenic plants was measured. The results showed that GUS activities with the promoter deleted to -287 and -271 from the translation initiation site were respectively about five and three times that of full-length promoter. There exists a cis-element which is important for the expressing activity in phloem from -271 to -176. Deletion from -176 to -141 resulted in a 20-30-fold reduction in GUS activity in leaves with weak activity in leaves and stems and losing GUS activity in roots. The functional domains of complementary sense gene promoter of CLCuV were firstly analyzed and compared. It was found that the promoter activity with the deletion of negative cis-elements was much stronger than that of full-length promoter and was about twelve times on average that of CaMV 35S promoter, suggesting that the promoter has great application potential. Results also provide novel clues for understanding the mechanisms of geminivirus gene regulation and interaction between virus and plant.

  17. CRISPR/CAS9: A TOOL TO CIRCUMSCRIBE COTTON LEAF CURL DISEASE

    Directory of Open Access Journals (Sweden)

    Zafar eIqbal

    2016-04-01

    Full Text Available The begomoviruses (family Geminiviridae associated with cotton leaf curl disease (CLCuD pose a major threat to cotton productivity in South-East Asia including Pakistan and India. These viruses have single-stranded, circular DNA genome, of ~2800 nt in size, encapsidated in twinned icosa-hedera, transmitted by ubiquitous whitefly and are associated with satellite molecules referred to as alpha- and betasatellite. To circumvent the proliferation of these viruses numerous techniques, ranging from conventional breeding to molecular approaches have been applied. Such devised strategies worked perfectly well for a short time period and then viruses relapse due to various reasons including multiple infections, where related viruses synergistically interact with each other, virus proliferation and evolution. Another shortcoming is, until now, that all molecular biology approaches are devised to control only helper begomoviruses but not to control associated satellites. Despite the fact that satellites could add various functions to helper begomoviruses, they remain ignored. Such conditions necessitate a very comprehensive technique that can offer best controlling strategy not only against helper begomoviruses but also their associated DNA-satellites. In the current scenario clustered regulatory interspaced short palindromic repeats (CRISPR/CRISPR associated nuclease 9 (Cas9 has proved to be versatile technique that has very recently been deployed successfully to control different geminiviruses. The CRISPR/Cas9 system has been proved to be a comprehensive technique to control different geminiviruses however, like previously used techniques, only a single virus is targeted and hitherto it has not been deployed to control begomovirus complexes associated with DNA-satellites. Here in this article, we proposed an inimitable, unique and broad spectrum controlling method based on multiplexed CRISPR/Cas9 system where a cassette of sgRNA is designed to target

  18. Feather mites (Acari, Astigmata from Azorean passerines (Aves, Passeriformes: lower species richness compared to European mainland

    Directory of Open Access Journals (Sweden)

    Rodrigues Pedro

    2015-01-01

    Full Text Available Ten passerine species were examined on three islands of the Azores (North Atlantic during 2013 and 2014 in order to identify their feather mite assemblages. We recorded 19 feather mite species belonging to four families of the superfamily Analgoidea (Analgidae, Proctophyllodidae, Psoroptoididae and Trouessartiidae. A high prevalence of feather mite species was recorded on the majority of the examined host species. Only three passerine species (Sylvia atricapilla, Regulus regulus and Serinus canaria presented the same full complex of mite species as commonly occurs in the plumage of their closest relatives in continental Europe. Passer domesticus presented the same limited fauna of feather mites living in the plumage as do its co-specifics in continental Europe. Carduelis carduelis bears the same feather mite species as do most of its continental populations in Europe, but it lacks one mite species occurring on this host in Egypt. Turdus merula, Pyrrhula murina and Fringilla coelebs are missing several mite species common to their continental relatives. This diminution could be explained by the founder effect, whereby a limited number of colonizing individuals did not transport the full set of feather mite species, or by the extinction of some mite species after initially having reached the Azores. The only individual of Motacilla cinerea sampled in this study presented a new host record for the mite species Trouessartia jedliczkai.

  19. Weed management practices affect the diversity and relative abundance of physic nut mites.

    Science.gov (United States)

    Saraiva, Althiéris de Sousa; Sarmento, Renato A; Erasmo, Eduardo A L; Pedro-Neto, Marçal; de Souza, Danival José; Teodoro, Adenir V; Silva, Daniella G

    2015-03-01

    Crop management practices determine weed community, which in turn may influence patterns of diversity and abundance of associated arthropods. This study aimed to evaluate whether local weed management practices influence the diversity and relative abundance of phytophagous and predatory mites, as well as mites with undefined feeding habits--of the families Oribatidae and Acaridae--in a physic nut (Jatropha curcas L.) plantation subjected to (1) within-row herbicide spraying and between-row mowing; (2) within-row herbicide spraying and no between-row mowing; (3) within-row weeding and between-row mowing; (4) within-row weeding and no between-row mowing; and (5) unmanaged (control). The herbicide used was glyphosate. Herbicide treatments resulted in higher diversity and relative abundance of predatory mites and mites with undefined feeding habit on physic nut shrubs. This was probably due to the toxic effects of the herbicide on mites or to removal of weeds. Within-row herbicide spraying combined with between-row mowing was the treatment that most contributed to this effect. Our results show that within-row weeds harbor important species of predatory mites and mites with undefined feeding habit. However, the dynamics of such mites in the system can be changed according to the weed management practice applied. Among the predatory mites of the family Phytoseiidae Amblydromalus sp. was the most abundant, whereas Brevipalpus phoenicis was the most frequent phytophagous mite and an unidentified oribatid species was the most frequent mite with undefined feeding habit.

  20. Diversity of House Dust Mite Species in Xishuangbanna Dai, a Tropical Rainforest Region in Southwest China

    Directory of Open Access Journals (Sweden)

    Jing-Miao Yu

    2015-01-01

    Full Text Available Purpose. To survey the species diversity of home dust mites (HDM in Xishuangbanna, a tropical rainforest region in Southwest China. Methods. From August 2010 to January 2011, mite-allergic patients and healthy controls were invited to participate. Dust samples from the patients’ homes were collected, and mites in the samples were isolated. Permanent slides were prepared for morphologically based species determination. Results. In total, 6316 mite specimens of morphologically identifiable species were found in 233 dust samples taken from 41 homes. The result shows that the mite family of Pyroglyphidae occupied the highest percentage of the total amount of mites collected, followed by Cheyletidae family. The most common adult Pyroglyphidae mites were Dermatophagoides (D. farinae, D. pteronyssinus, and D. siboney. The most common mites found from other families were Blomia tropicalis, Tyrophagus putrescentiae, and Aleuroglyphus ovatus. Four main allergenic dust mite species D. farinae, D. pteronyssinus, D. siboney, and Blomia tropicalis were found to be coinhabiting in 6/41 homes. Conclusion. The HDM population in homes in Xishuangbanna, a tropical rainforest region in Southwest China, has its own characteristics. It has rich dust mite species and the dust mite densities do not show significant variation across seasons.

  1. International consensus (ICON) on: clinical consequences of mite hypersensitivity, a global problem.

    Science.gov (United States)

    Sánchez-Borges, Mario; Fernandez-Caldas, Enrique; Thomas, Wayne R; Chapman, Martin D; Lee, Bee Wah; Caraballo, Luis; Acevedo, Nathalie; Chew, Fook Tim; Ansotegui, Ignacio J; Behrooz, Leili; Phipatanakul, Wanda; Gerth van Wijk, Roy; Pascal, Demoly; Rosario, Nelson; Ebisawa, Motohiro; Geller, Mario; Quirce, Santiago; Vrtala, Susanne; Valenta, Rudolf; Ollert, Markus; Canonica, Giorgio Walter; Calderón, Moises A; Barnes, Charles S; Custovic, Adnan; Benjaponpitak, Suwat; Capriles-Hulett, Arnaldo

    2017-01-01

    Since mite allergens are the most relevant inducers of allergic diseases worldwide, resulting in significant morbidity and increased burden on health services, the International Collaboration in Asthma, Allergy and Immunology (iCAALL), formed by the American Academy of Allergy, Asthma and Immunology (AAAAI), the American College of Allergy, Asthma and Immunology (ACAAI), the European Academy of Allergy and Clinical Immunology (EAACI), and the World Allergy Organization (WAO), has proposed to issue an International Consensus (ICON) on the clinical consequences of mite hypersensitivity. The objectives of this document are to highlight aspects of mite biology that are clinically relevant, to update the current knowledge on mite allergens, routes of sensitization, the genetics of IgE responses to mites, the epidemiologic aspects of mite hypersensitivity, the clinical pictures induced by mites, the diagnosis, specific immunotherapeutic approaches, and prevention.

  2. Validation of an automated mite counter for Dermanyssus gallinae in experimental laying hen cages.

    Science.gov (United States)

    Mul, Monique F; van Riel, Johan W; Meerburg, Bastiaan G; Dicke, Marcel; George, David R; Groot Koerkamp, Peter W G

    2015-08-01

    For integrated pest management (IPM) programs to be maximally effective, monitoring of the growth and decline of the pest populations is essential. Here, we present the validation results of a new automated monitoring device for the poultry red mite (Dermanyssus gallinae), a serious pest in laying hen facilities world-wide. This monitoring device (called an "automated mite counter") was validated in experimental laying hen cages with live birds and a growing population of D. gallinae. This validation study resulted in 17 data points of 'number of mites counted' by the automated mite counter and the 'number of mites present' in the experimental laying hen cages. The study demonstrated that the automated mite counter was able to track the D. gallinae population effectively. A wider evaluation showed that this automated mite counter can become a useful tool in IPM of D. gallinae in laying hen facilities.

  3. A method for both mass and individual rearing of fungivorous astigmatid mites (Acari).

    Science.gov (United States)

    Okabe, K; Oconnor, B M

    2001-01-01

    Several species of common fungi were assessed as food for fungivorous astigmatid mites. Hypocrea nigricans, Botrytis cinerea and Flammulina velutipes were generally good food sources for most mites examined. Fungal mycelia growing on PDA (potato dextrose agar) medium were not only nutritionally adequate but the system also maintained high humidity through the water-based agar medium. Among acarid mites, most species of Rhizoglyphinae could be reared easily with the method. Although filter-feeding histiostomatid mites do not feed directly on hyphae, some species were successfully maintained with the same method through multiple generations. Presumably, these mites obtained sufficient nutrition from the agar medium and fungal metabolites leaching into it. Most species ultimately produced dispersing heteromorphic deutonymphs on these media. Individual mites were also maintained in isolation within glass rings on fungal colonies. Using this technique, we were able to compare developmental periods, fecundity and survival periods of mites reared under different conditions.

  4. Beyond Focal Pests: Impact of a Neonicotinoid Seed Treatment and Resistant Soybean Lines on a Non-Target Arthropod

    Science.gov (United States)

    Özsisli, Tülin; Prischmann-Voldseth, Deirdre A.

    2016-01-01

    Integrated pest management (IPM) tactics may effectively control focal pests, but it is also important to test the compatibility of different tactics, and consider non-target organisms. We investigated the effects of a neonicotinoid seed treatment and Rag resistance genes used for soybean aphid (Aphis glycines Matsumura) control on reproduction of a non-target herbivore (twospotted spider mite, Tetranychus urticae Koch) in short-term greenhouse experiments. We also examined interactions between spider mites and a specialist phytoseiid mite [Ambylseius fallacis (Garman)] and assessed the effects of a co-occurring opportunistic omnivore [Frankliniella occidentalis (Pergande)] by including thrips density as a covariate. There were no interactive or main effects of the presence of Rag genes on the densities of any of the arthropods. Overall, effects of the seed treatment on spider mite densities varied, with no difference when mites were confined in clip cages, and higher populations on seed-treated plants when on whole plants. Predatory mites had a consistent negative impact on spider mites, and densities of A. fallacis immatures were similar between seed treated and non-seed treated plants. However, the relationship between spider mite and thrips densities was different between these two plant types, but only in the clip cage experiment lacking predatory mites. This research highlights the importance of considering how IPM tactics might affect non-target organisms. PMID:27845714

  5. Three eriophyoid mite species (Acari: Eriophyoidea: Eriophyidae) from Iran.

    Science.gov (United States)

    Xue, Xiao-Feng; Sadeghi, Hussein; Honarmand, Arash

    2016-01-01

    Three mite species of the family Eriophyidae from Iran are described and illustrated. They are: Tegolophus marrubiumer sp. nov. on Marrubium vulgare L. (Lamiaceae); Phyllocoptes sp. cf. balasi Farkas, 1962 on Sanguisorba minor Scop. subsp. minor (Rosaceae) and Aceria fasciculifolis sp. nov. on Astragalus fasciculifolius Boiss. (Fabaceae). Both new species described herein are vagrants on their respective host plants.

  6. Role of Predatory Mites in Persistent Nonoccupational Allergic Rhinitis

    Directory of Open Access Journals (Sweden)

    Paloma Poza Guedes

    2016-01-01

    Full Text Available Mites can sensitize and induce atopic disease in predisposed individuals and are an important deteriorating factor in patients with allergic rhinitis, asthma, and atopic dermatitis. Although Pyroglyphidae mites have been extensively studied, very scarce reports are available on Cheyletidae spp. especially regarding human respiratory pathology. The main objective of the present study is to investigate the clinical role of this predator mite (Cheyletus eruditus as a respiratory antigen in a selected sensitized human population. Fifty-two adult patients were recruited from the outpatient allergy clinic to assess their eligibility for the study. The thirty-seven subjects with persistent allergic rhinitis (PAR who fulfilled the ARIA criteria had a positive IgE response confirmed by skin prick test (SPT to C. eruditus. Only those individuals (37/47 with a positive SPT to C. eruditus showed a positive nasal provocation test (NPT, while 10 patients with nonallergic mild-to-moderate persistent rhinitis, control group, had a negative NPT with C. eruditus. The present paper describes a new role for the predator mite Cheyletus eruditus as a respiratory allergen in a selected subset of patients in a subtropical environment afflicted with persistent nonoccupational allergic rhinitis.

  7. Incidense of spider mites in South Texas cotton fields

    Science.gov (United States)

    The incidence of spider mites was evaluated· in four locations of south Texas between Progreso (Hidalgo Co.) to Bishop (Nueces Co.). This is an area with a south to north transect of 125 miles from south Progreso to north Bishop (respectively).The other two intermediate sampled locations were Harlin...

  8. Host Finding Behaviour of the Coconut Mite Aceria Guerreronis

    NARCIS (Netherlands)

    Melo, J.W.S.; Lima, D.B.; Sabelis, M.W.; Pallini, A.; Gondim Jr., M.G.C.

    2014-01-01

    For the coconut mite, Aceria guerreronis Keifer, its host plant, the coconut palm, is not merely a source of food, but more generally a habitat to live in for several generations. For these minute organisms, finding a new plant is difficult and risky, especially because their main mode of dispersal

  9. Ubiquity and diversity of human-associated Demodex mites.

    Directory of Open Access Journals (Sweden)

    Megan S Thoemmes

    Full Text Available Demodex mites are a group of hair follicle and sebaceous gland-dwelling species. The species of these mites found on humans are arguably the animals with which we have the most intimate interactions. Yet, their prevalence and diversity have been poorly explored. Here we use a new molecular method to assess the occurrence of Demodex mites on humans. In addition, we use the 18S rRNA gene (18S rDNA to assess the genetic diversity and evolutionary history of Demodex lineages. Within our samples, 100% of people over 18 years of age appear to host at least one Demodex species, suggesting that Demodex mites may be universal associates of adult humans. A phylogenetic analysis of 18S rDNA reveals intraspecific structure within one of the two named human-associated Demodex species, D. brevis. The D. brevis clade is geographically structured, suggesting that new lineages are likely to be discovered as humans from additional geographic regions are sampled.

  10. Identification of astigmatid mites using ITS2 and COI regions.

    Science.gov (United States)

    Yang, Bin; Cai, Junlong; Cheng, Xunjia

    2011-02-01

    Identification of astigmatid mites based on their morphological characteristics is difficult because of the similarity of their organs, especially in immature mites. The ribosomal second internal transcribed spacer (ITS2) and the mitochondrial cytochrome oxidase subunit I (COI) regions are highly conserved in the eukaryotes and are usually used as barcodes. The ITS2 and COI regions of six species of astigmatid mites (Aleuroglyphus ovatus, Blomia tropicalis, Dermatophagoides farinae, Dermatophagoides pteronyssinus, Euroglyphus maynei, Tyrophagus putrescentiae) were obtained by polymerase chain reaction and sequenced. The lengths of the ITS2 sequences varied from 316 to 488 bp, while the COI regions were 377 or 378 bp long. Considering the ITS2 genes, the intraspecific genetic distance was in the range of 0.00-0.077844, whereas the interspecific genetic distance was 0.202426-0.912959. The values were 0.000-0.029748 and 0.138403-0.279304 for intra- and interspecific genetic distances when COI genes were used. The phylogenetic trees inferred from the ITS2 and the COI regions, by using maximum parsimony and neighbor-joining methods, were identical to those based on their morphological classification. Thus, the ITS2 and COI regions can be applied as barcodes to identify different species of astigmatid mites.

  11. Molecular sabotage of host plant defenses by spider mites

    NARCIS (Netherlands)

    Villarroel Figueroa, C.A.

    2016-01-01

    Plants constitute an ample source of nutrients for a diversity of organisms that include viruses, microbes, nematodes, insects, and mites. To protect their resources, plants possess a robust immune system that establishes structural and biochemical defenses to fight invaders. Some of these defenses

  12. Ubiquity and diversity of human-associated Demodex mites.

    Science.gov (United States)

    Thoemmes, Megan S; Fergus, Daniel J; Urban, Julie; Trautwein, Michelle; Dunn, Robert R

    2014-01-01

    Demodex mites are a group of hair follicle and sebaceous gland-dwelling species. The species of these mites found on humans are arguably the animals with which we have the most intimate interactions. Yet, their prevalence and diversity have been poorly explored. Here we use a new molecular method to assess the occurrence of Demodex mites on humans. In addition, we use the 18S rRNA gene (18S rDNA) to assess the genetic diversity and evolutionary history of Demodex lineages. Within our samples, 100% of people over 18 years of age appear to host at least one Demodex species, suggesting that Demodex mites may be universal associates of adult humans. A phylogenetic analysis of 18S rDNA reveals intraspecific structure within one of the two named human-associated Demodex species, D. brevis. The D. brevis clade is geographically structured, suggesting that new lineages are likely to be discovered as humans from additional geographic regions are sampled.

  13. Plant feeding by a predatory mite inhabiting cassava.

    Science.gov (United States)

    Magalhães, S; Bakker, F M

    2002-01-01

    Plant feeding by arthropod predators may strongly affect the dynamics of bi-and tri-trophic interactions. We tested whether a predatory mite, Typhlodromalus aripo, feeds upon its host plant, cassava. This predator species is an effective biological control agent of Monoychellus tanajoa (the cassava green mite or CGM) a herbivorous mite specific to cassava. We developed a technique to detect plant feeding, based on the use of a systemic insecticide. We found that T. aripo feeds upon plant-borne material, while other predatory mite species, Neoseiulus idaeus and Phytoseiulus persimilis, do not. Subsequently, we measured survival of juveniles and adult females of T. aripo and N. idaeus, both cassava-inhabiting predator species, on cassava leaf discs. Survival of T. aripo was higher than that of N. idaeus. Thus, T. aripo was able to withstand longer periods of prey scarcity. Because CGM populations fluctuate yearly and are heterogeneously distributed within plants, plant feeding may facilitate the persistence of populations of T. aripo in cassava fields and its control of CGM outbreaks.

  14. Role of Predatory Mites in Persistent Nonoccupational Allergic Rhinitis

    Science.gov (United States)

    Poza Guedes, Paloma; Sánchez Machín, Inmaculada; Matheu, Víctor; Iraola, Víctor

    2016-01-01

    Mites can sensitize and induce atopic disease in predisposed individuals and are an important deteriorating factor in patients with allergic rhinitis, asthma, and atopic dermatitis. Although Pyroglyphidae mites have been extensively studied, very scarce reports are available on Cheyletidae spp. especially regarding human respiratory pathology. The main objective of the present study is to investigate the clinical role of this predator mite (Cheyletus eruditus) as a respiratory antigen in a selected sensitized human population. Fifty-two adult patients were recruited from the outpatient allergy clinic to assess their eligibility for the study. The thirty-seven subjects with persistent allergic rhinitis (PAR) who fulfilled the ARIA criteria had a positive IgE response confirmed by skin prick test (SPT) to C. eruditus. Only those individuals (37/47) with a positive SPT to C. eruditus showed a positive nasal provocation test (NPT), while 10 patients with nonallergic mild-to-moderate persistent rhinitis, control group, had a negative NPT with C. eruditus. The present paper describes a new role for the predator mite Cheyletus eruditus as a respiratory allergen in a selected subset of patients in a subtropical environment afflicted with persistent nonoccupational allergic rhinitis. PMID:27445552

  15. Stability evaluation of house dust mite vaccines for sublingual immunotherapy

    Directory of Open Access Journals (Sweden)

    MARIJA GAVROVIĆ-JANKULOVIĆ

    2010-01-01

    Full Text Available Allergen-specific immunotherapy with house dust mite (HDM allergen extracts can effectively alleviate the symptoms of allergic rhinitis and asthma. The efficacy of the immunotherapeutic treatment is highly dependent on the quality of house dust mite vaccines. This study was performed to assess the stability of house dust mite allergen vaccines prepared for sublingual immunotherapy. Lyophilized Dermatophagoides pteronyssinus (Dpt mite bodies were the starting material for the production of sublingual vaccines in four therapeutic concentrations. The stability of the extract for vaccine production, which was stored below 4 °C for one month, showed consistence in the protein profile in SDS PAGE. ELISA-inhibition showed that the potencies of Dpt vaccines during a 12 month period were to 65–80 % preserved at all analyzed therapeutic concentrations. This study showed that glycerinated Dpt vaccines stored at 4 °C preserved their IgE-binding potential during a 12 month period, implying their suitability for sublingual immunotherapeutic treatment of HDM allergy.

  16. [Varroa mites in the apiaries of Campania region].

    Science.gov (United States)

    Mazzone, P; Caprio, E; Cringoli, G

    2004-06-01

    Mites in the genus Varroa are obligate ectoparasites of honey bee populations worldwide. Recent evidence from morphological, geographical, and especially genetic variation has spurred an important revision of Varroa taxonomy. Specifically, mitochondrial DNA (mtDNA) evidence suggests that the main mite pest on western honey bees (Apis mellifera) is not Varroa jacobsoni, as first described, but a distinct species now named Varroa destructor. Genetic markers also have been used to support a taxonomic basis for regional differences in how Varroa mites impact honey bees. Recent morphometric and molecular studies confirmed the presence of the species V. destructor also in the apiaries of the Campania region of southern Italy. In the three-year period 2001-2003 a survey was conducted in 118 municipalities of the five provinces of the Campania region in order to add data to the limited epidemiological information available regarding Varroa destructor in this zone. The level of infestation by the mite was assessed on a total of 521 apiaries (241 apiaries were inspected on 2001, 154 on 2002, and 126 on 2003). In each apiary, 100 comb cells were examined and in each province the level of infestation was calculated using the following formula: (number of Varroa specimens/number of open comb cells) x 100. In order to display the level of infestation, Geographical Information Systems were used in order to draw parasitological maps.

  17. Sampling plans for pest mites on physic nut.

    Science.gov (United States)

    Rosado, Jander F; Sarmento, Renato A; Pedro-Neto, Marçal; Galdino, Tarcísio V S; Marques, Renata V; Erasmo, Eduardo A L; Picanço, Marcelo C

    2014-08-01

    The starting point for generating a pest control decision-making system is a conventional sampling plan. Because the mites Polyphagotarsonemus latus and Tetranychus bastosi are among the most important pests of the physic nut (Jatropha curcas), in the present study, we aimed to establish sampling plans for these mite species on physic nut. Mite densities were monitored in 12 physic nut crops. Based on the obtained results, sampling of P. latus and T. bastosi should be performed by assessing the number of mites per cm(2) in 160 samples using a handheld 20× magnifying glass. The optimal sampling region for T. bastosi is the abaxial surface of the 4th most apical leaf on the branch of the middle third of the canopy. On the abaxial surface, T. bastosi should then be observed on the side parts of the middle portion of the leaf, near its edge. As for P. latus, the optimal sampling region is the abaxial surface of the 4th most apical leaf on the branch of the apical third of the canopy on the abaxial surface. Polyphagotarsonemus latus should then be assessed on the side parts of the leaf's petiole insertion. Each sampling procedure requires 4 h and costs US$ 7.31.

  18. Verified and potential pathogens of predatory mites (Acari: Phytoseiidae)

    NARCIS (Netherlands)

    Schütte, C.; Dicke, M.

    2008-01-01

    Several species of phytoseiid mites (Acari: Phytoseiidae), including species of the genera Amblyseius, Galendromus, Metaseiulus, Neoseiulus, Phytoseiulus and Typhlodromus, are currently reared for biological control of various crop pests and/or as model organisms for the study of predator¿prey inter

  19. 冰壶运动员致胜心理因素探析%Analysis on Winning Psychological Factors of Curling Athletes

    Institute of Scientific and Technical Information of China (English)

    史孟玉; 姜淼淼

    2014-01-01

    针对我国冰壶运动发展的优势和存在的问题,抓住冰壶运动独具的项目特征,分析冰壶运动员致胜心理因素,加快提升我国冰壶运动整体竞技能力,力争在索契冬奥会上取得佳绩,是我国冰壶运动教练员、运动员亟待解决的重要课题。良好的心理状态是冰壶运动员最佳竞技状态形成的重要因素。从团队精神、动机、心理准备、自信心、注意力和焦虑控制等方面探究冰壶运动员致胜心理因素,旨在寻求提高冰壶运动训练水平、提升冰壶运动员整体竞技能力和冰壶运动员在比赛中取得优异成绩的突破口。%Aiming at the advantages and problems of Chinese curling development,stressing the unique characteristics of curling,analyzing the winning psychological factors of curling athletes, improving the overall competitive ability of Chinese curling and striving for good performance in Olympics in Sochi is the important task which should be solved quickly by Chinese curling coaches and athletes. A good mental state is the important factor of curling athletes being at their best competitive form. Analyze the winning psychological factors of curling athletes from team spirit, motivation,psychological preparation, self-confidence,attention and anxious control,in order to seek a breach which improves training level of curling,improve the overall competitive ability of curling athletes and get good performance in competitions.

  20. Structural Mechanisms of Inactivation in Scabies Mite Serine Protease Paralogues

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Katja; Langendorf, Christopher G.; Irving, James A.; Reynolds, Simone; Willis, Charlene; Beckham, Simone; Law, Ruby H.P.; Yang, Sundy; Bashtannyk-Puhalovich, Tanya A.; McGowan, Sheena; Whisstock, James C.; Pike, Robert N.; Kemp, David J.; Buckle, Ashley M.; (Monash); (Queensland Inst. of Med. Rsrch.)

    2009-08-07

    The scabies mite (Sarcoptes scabiei) is a parasite responsible for major morbidity in disadvantaged communities and immuno-compromised patients worldwide. In addition to the physical discomfort caused by the disease, scabies infestations facilitate infection by Streptococcal species via skin lesions, resulting in a high prevalence of rheumatic fever/heart disease in affected communities. The scabies mite produces 33 proteins that are closely related to those in the dust mite group 3 allergen and belong to the S1-like protease family (chymotrypsin-like). However, all but one of these molecules contain mutations in the conserved active-site catalytic triad that are predicted to render them catalytically inactive. These molecules are thus termed scabies mite inactivated protease paralogues (SMIPPs). The precise function of SMIPPs is unclear; however, it has been suggested that these proteins might function by binding and protecting target substrates from cleavage by host immune proteases, thus preventing the host from mounting an effective immune challenge. In order to begin to understand the structural basis for SMIPP function, we solved the crystal structures of SMIPP-S-I1 and SMIPP-S-D1 at 1.85 {angstrom} and 2.0 {angstrom} resolution, respectively. Both structures adopt the characteristic serine protease fold, albeit with large structural variations over much of the molecule. In both structures, mutations in the catalytic triad together with occlusion of the S1 subsite by a conserved Tyr200 residue is predicted to block substrate ingress. Accordingly, we show that both proteases lack catalytic function. Attempts to restore function (via site-directed mutagenesis of catalytic residues as well as Tyr200) were unsuccessful. Taken together, these data suggest that SMIPPs have lost the ability to bind substrates in a classical 'canonical' fashion, and instead have evolved alternative functions in the lifecycle of the scabies mite.

  1. Food stress causes sex-specific maternal effects in mites.

    Science.gov (United States)

    Walzer, Andreas; Schausberger, Peter

    2015-08-01

    Life history theory predicts that females should produce few large eggs under food stress and many small eggs when food is abundant. We tested this prediction in three female-biased size-dimorphic predatory mites feeding on herbivorous spider mite prey: Phytoseiulus persimilis, a specialized spider mite predator; Neoseiulus californicus, a generalist preferring spider mites; Amblyseius andersoni, a broad diet generalist. Irrespective of predator species and offspring sex, most females laid only one small egg under severe food stress. Irrespective of predator species, the number of female but not male eggs decreased with increasing maternal food stress. This sex-specific effect was probably due to the higher production costs of large female than small male eggs. The complexity of the response to the varying availability of spider mite prey correlated with the predators' degree of adaptation to this prey. Most A. andersoni females did not oviposit under severe food stress, whereas N. californicus and P. persimilis did oviposit. Under moderate food stress, only P. persimilis increased its investment per offspring, at the expense of egg number, and produced few large female eggs. When prey was abundant, P. persimilis decreased the female egg sizes at the expense of increased egg numbers, resulting in a sex-specific egg size/number trade-off. Maternal effects manifested only in N. californicus and P. persimilis. Small egg size correlated with the body size of daughters but not sons. Overall, our study provides a key example of sex-specific maternal effects, i.e. food stress during egg production more strongly affects the sex of the large than the small offspring.

  2. Clinical effectiveness of a mite allergen-impermeable bed-covering system in asthmatic mite-sensitive patients.

    NARCIS (Netherlands)

    Bemt, E.A.J.M. van den; Knapen, L. van; Vries, M.P. de; Jansen, M.; Cloosterman, S.G.M.; Schayck, C.P. van

    2004-01-01

    BACKGROUND: Exposure to allergens plays a role in the development of bronchial hyperresponsiveness and in the chronic inflammatory response seen in asthmatic patients. House dust mites (HDMs) are an important source of allergen. Reduction of these allergens might lead to better lung function and red

  3. Global divergence of the human follicle mite Demodex folliculorum: Persistent associations between host ancestry and mite lineages.

    Science.gov (United States)

    Palopoli, Michael F; Fergus, Daniel J; Minot, Samuel; Pei, Dorothy T; Simison, W Brian; Fernandez-Silva, Iria; Thoemmes, Megan S; Dunn, Robert R; Trautwein, Michelle

    2015-12-29

    Microscopic mites of the genus Demodex live within the hair follicles of mammals and are ubiquitous symbionts of humans, but little molecular work has been done to understand their genetic diversity or transmission. Here we sampled mite DNA from 70 human hosts of diverse geographic ancestries and analyzed 241 sequences from the mitochondrial genome of the species Demodex folliculorum. Phylogenetic analyses recovered multiple deep lineages including a globally distributed lineage common among hosts of European ancestry and three lineages that primarily include hosts of Asian, African, and Latin American ancestry. To a great extent, the ancestral geography of hosts predicted the lineages of mites found on them; 27% of the total molecular variance segregated according to the regional ancestries of hosts. We found that D. folliculorum populations are stable on an individual over the course of years and that some Asian and African American hosts maintain specific mite lineages over the course of years or generations outside their geographic region of birth or ancestry. D. folliculorum haplotypes were much more likely to be shared within families and between spouses than between unrelated individuals, indicating that transmission requires close contact. Dating analyses indicated that D. folliculorum origins may predate modern humans. Overall, D. folliculorum evolution reflects ancient human population divergences, is consistent with an out-of-Africa dispersal hypothesis, and presents an excellent model system for further understanding the history of human movement.

  4. Management of apple orchards to conserve generalist phytoseiid mites suppresses two-spotted spider mite, Tetranychus urticae (Acari: Tetranychidae).

    Science.gov (United States)

    Funayama, Ken; Komatus, Michiyo; Sonoda, Shoji; Takahashi, Isao; Hara, Kazuko

    2015-01-01

    To improve the success of integrated pest management (IPM) in apple orchards, we investigated whether generalist phytoseiid mites have suppressed the occurrence of Tetranychus urticae. In Akita Prefecture, northern Japan, in 2012 and 2013, two types of experimental plot were compared. Conservation plots had been managed for the conservation of generalist phytoseiid mites by selective chemical spraying without mowing since 2009. Conventional plots were managed by non-selective chemical spraying with regular mowing. The conservation plots had significantly fewer T. urticae adult females per tree in both years. Two species of generalist phytoseiid mites-Typhlodromus vulgaris and Amblyseius tsugawai-were continuously present in the conservation plots, with only a few T. urticae. The conservation plots had significantly more A. tsugawai adult females in the undergrowth in both years, and significantly more T. vulgaris adult females on apple leaves in 2012. Typhlodromus vulgaris was continuously present in the conservation plots but was scarce from late May to early August in the conventional plots. In the presence of T. vulgaris, low numbers of T. urticae did not increase on apple leaves. These results indicate that the generalist phytoseiid mites serve as important biological control agents in IPM in apple orchards.

  5. Predation of Neozygites tanajoae-infected cassava green mites by the predatory mite, Typhlodromalus aripo (Acari: Phytoseiidae

    Directory of Open Access Journals (Sweden)

    Serge L. Ariori

    2007-06-01

    Full Text Available Typhlodromalus aripo is the most successful of the Neotropical predatory mites released for the classical biological control of the cassava green mite, Mononychellus tanajoa, in Africa. A few isolates of the entomopthoralean fungus, Neozygites tanajoae, which causes epizootics in M. tanajoa populations in Brazil, were imported to be released in Africa for the control of M. tanajoa. The present study evaluated the feeding preference of T. aripo for M. tanajoa infected by N. tanajoae in a preliminary attempt to determine the interaction between the two biological control agents. The feeding preferences of normal and starved, for 24 and 48 h, T. aripo for the healthy M. tanajoa and for those exposed to N. tanajoe were compared in choice and no choice tests. In general, T. aripo consumed significant quantities of infected M. tanajoa along with the healthy ones. Although, they appeared to have a slight preference for healthy M. tanajoa, significant difference (P < 0.05 was seen only in a no choice test when the predators that were starved for 24 h were used. The consumption of pathogen-infected pest mites by the predatory mites can reduce the effectiveness of the microbial control agent.

  6. Advances of research on Cotton leaf curl virus%棉花曲叶病毒研究进展

    Institute of Scientific and Technical Information of China (English)

    丁小兰; 赵竹; 李明福

    2013-01-01

    The Cotton leaf curl virus as a quarantine virus in China is severely harmful to the production of the cotton. It caused destructive damage on cotton production in Pakistan and India. The virus could be transimitted by the whitefly and had a wide host range. In 2006, the Cotton leaf curl virus was found to infect Hibiscus rosa -sinensis in Guangdong. Moreover, in 2010, CLCuV was reported to be associated with cotton leaf curl disease in a experimental field of Nanning, Guangxi province in China. Cotton is an important crop in China, once the virus is spread to the main cotton producing areas, the consequences would be disastrous. In this paper, the variants of the virus, distribution and popular trend, disease epidemiology, the influence of CLCuV on cotton production and quality traits and disease control are analysed. In addition, the interesting issues and effective management measures for CLCuV were discussed also.%棉花曲叶病毒(Cotton leaf curl virus,CLCuV)是我国的进境检疫性有害生物,严重危害棉花生长,在巴基斯坦和印度的棉花产区已造成毁灭性灾害.该病毒主要由烟粉虱传播,寄主范围广泛.2006年在广东首次发现棉花曲叶病毒(CLCuV)入侵我国危害朱槿,2010年有报道证实CLCuV已侵染广西南宁试验田的棉花.我国是棉花生产大国,该病毒一旦扩散传播到棉花主产区,后果将不堪设想.本文对CLCuV的变异、国内外分布和流行趋势、影响棉花曲叶病流行的因素、病毒对棉花的品质和产量的影响及病害治理等方面进行综述,并探讨了棉花曲叶病毒研究存在的问题及有效防止该病毒传播和扩散的措施.

  7. Vector wind, horizontal divergence, wind stress and wind stress curl from SEASAT-SASS at one degree resolution

    Science.gov (United States)

    Pierson, W. J., Jr.; Sylvester, W. B.; Salfi, R. E.

    1984-01-01

    Conventional data obtained in 1983 are contrasted with SEASAT-A scatterometer and scanning multichannel microwave radiometer (SMMR) data to show how observations at a single station can be extended to an area of about 150,000 square km by means of remotely sensed data obtained in nine minutes. Superobservations at a one degree resolution for the vector winds were estimated along with their standard deviations. From these superobservations, the horizontal divergence, vector wind stress, and the curl of the wind stress can be found. Weather forecasting theory is discussed and meteorological charts of the North Pacific Ocean are presented. Synoptic meteorology as a technique is examined.

  8. [Morphological adaptations of acariform mites (Acari: Acariformes) to permanent parasitism on mammals].

    Science.gov (United States)

    Bochkov, A V

    2007-01-01

    The external morphological adaptations to parasitism in acariform mites (Acari: Acariformes), permanently parasiting mammals, are briefly summated and analyzed. According to several external morphological criteria (structures of gnathosoma, idiosoma, setation, legs and life cycle), the following six morphoecotypes were established: skin mites (i)-- Cheyletidae, Chirorhynchobiidae, Lobalgidae, Myobiidae, Myocoptidae (the most part), Rhyncoptidae, Psoroptidae; fur mites (ii)--Atopomelidae, Clirodiscidae, Listrophoridae, Myocoptidae (Trichoecius only); skin burrowing mites (iii)--Sarcoptidae; intradermal mites (iv) - sorergatidae and Demodicidae; interstitial mites (v) - pimyodicidae; respiratory mites (vi) - reynetidae, Gastronyssidae, Lemurnyssidae, Pneumocoptidae. In the case of prostigmatic mites, the detailed reconstruction of the origin and evolution of "parasitic" morphoecotypes is possible due to the tentative phylogenetic hypotheses, which were proposed for the infraorder Eleutherengon, a, including the most part of the permanent mammalian parasites among prostigmatic mites (Kethley in Norton, 1993; Bochkov, 2002). The parasitism of Speleognathinae (Ereynetidae) in the mammalian respiratory tract arose independently of the other prostigmats. It is quite possible that these mites switched on mammals from birds, because they are more widely represented on these hosts than on mammals. The prostigmatic parasitism on mammalian skin seems to be originated independently in myobiids, in the five cheyletid tribes, Cheyletiellini, Niheliini, and Teinocheylini, Chelonotini, Cheyletini, and, probably, in a cheyletoid ansector of the sister families Psorergatidae-Demodicidae (Bochkov, Fain, 2001; Bochkov, 2002). Demodicids and psorergatids developed adaptations to parasitism in the skin gland ducts and directly in the epithelial level, respectively in the process of the subsequent specialization. Mites of the family Epimyodicidae belong to the phylogenetic line

  9. Prediction and characterization of Tomato leaf curl New Delhi virus (ToLCNDV) responsive novel microRNAs in Solanum lycopersicum.

    Science.gov (United States)

    Pradhan, Bhubaneswar; Naqvi, Afsar Raza; Saraf, Shradha; Mukherjee, Sunil Kumar; Dey, Nrisingha

    2015-01-02

    Tomato leaf curl New Delhi virus (ToLCNDV) infects tomato (Solanum lycopersicum) plants and causes severe crop losses. As the microRNAs (miRNAs) are deregulated during stressful events, such as biotic stress, we wanted to study the effect of ToLCNDV infection on tomato miRNAs. We constructed two libraries, isolating small RNAs (sRNAs) from healthy (HT) and ToLCNDV infected (IT) tomato leaves, and sequenced the library-specific sRNAs using the next generation sequencing (NGS) approach. These data helped predict 112 mature miRNA sequences employing the miRDeep-P program. A substantial number (58) of the sequences were 24-mer in size, which was a bit surprising. Based on the calculation of precision values, 53 novel miRNAs were screened from the predicted sequences. Nineteen of these were chosen for expression analysis; a northern blot analysis showed 15 to be positive. Many of the predicted miRNAs were up-regulated following viral infection. The target genes of the miRNAs were also predicted and the expression analysis of selected transcripts showed a typical inverse relation between the accumulation of target transcripts and the abundance of corresponding miRNAs. Furthermore, the cleavage sites of the target transcripts for three novel miRNAs were mapped, confirming the correct annotation of the miRNA-targets. The sRNA deep sequencing clearly revealed that the virus modulated global miRNA expression in the host. The validated miRNAs (Tom_4; Tom_14; Tom_17; Tom_21; Tom_29; Tom_43) could be valuable tools for understanding the ToLCNDV-tomato interaction, ultimately leading to the development of a virus-resistant tomato plant. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. High resolution genetic mapping uncovers chitin synthase-1 as the target-site of the structurally diverse mite growth inhibitors clofentezine, hexythiazox and etoxazole in Tetranychus urticae.

    Science.gov (United States)

    Demaeght, Peter; Osborne, Edward J; Odman-Naresh, Jothini; Grbić, Miodrag; Nauen, Ralf; Merzendorfer, Hans; Clark, Richard M; Van Leeuwen, Thomas

    2014-08-01

    The acaricides clofentezine, hexythiazox and etoxazole are commonly referred to as 'mite growth inhibitors', and clofentezine and hexythiazox have been used successfully for the integrated control of plant mite pests for decades. Although they are still important today, their mode of action has remained elusive. Recently, a mutation in chitin synthase 1 (CHS1) was linked to etoxazole resistance. In this study, we identified and investigated a Tetranychus urticae strain (HexR) harboring recessive, monogenic resistance to each of hexythiazox, clofentezine, and etoxazole. To elucidate if there is a common genetic basis for the observed cross-resistance, we adapted a previously developed bulk segregant analysis method to map with high resolution a single, shared resistance locus for all three compounds. This finding indicates that the underlying molecular basis for resistance to all three compounds is identical. This locus is centered on the CHS1 gene, and as supported by additional genetic and biochemical studies, a non-synonymous variant (I1017F) in CHS1 associates with resistance to each of the tested acaricides in HexR. Our findings thus demonstrate a shared molecular mode of action for the chemically diverse mite growth inhibitors clofentezine, hexythiazox and etoxazole as inhibitors of an essential, non-catalytic activity of CHS1. Given the previously documented cross-resistance between clofentezine, hexythiazox and the benzyolphenylurea (BPU) compounds flufenoxuron and cycloxuron, CHS1 should be also considered as a potential target-site of insecticidal BPUs.

  11. [Co-adaptation between mites (Arachnida: Klinckowstroemiidae) and Passalidae beetles (Insecta: Coleoptera)].

    Science.gov (United States)

    Villegas-Guzmán, Gabriel A; Francke, Oscar F; Pérez, Tila M; Reyes-Castillo, Pedro

    2012-06-01

    Mites of the family Klinckowstroemiidae establish an association with beetles of the family Passalidae known as phoresy. In order to obtain information about this association, we analyzed the relationship between mites of the family Klinckowstroemiidae and beetles of the family Passalidae, as adult mites have been exclusively collected from host beetles. We examined 1 150 beetles collected in seven states of the Mexican Republic, and found 19 species of klinckowstroemiid mites associated with 168 passalids, that belong to 28 different species in 15 genera. Host specificity between species of both groups does not exist, as one species of passalid beetle can have several different symbionts; conversely, a given mite species can associate with passalid beetles of different species and even of different genera. This way, Odontotaenius zodiacus has been found associated with mites of seven species of the genus Klinckowstroemia. Besides, Klinckowstroemia valdezi is associated with five species of passalids. Furthermore, two and even three different species of mites have been found on one host beetle (synhospitality). The lack of congruence between the phylogenies of the mites and that of the beetles indicates that a process of co-adaptation by colonization is going on, because the association is due to the resources that passalid beetles can offer to the mites, like transportation, food and refuge. Since these resources are not host-specific, the klinckowstroemiid mites can climb onto virtually any species of passalid beetles occurring on the same habitat.

  12. Host-parasite interaction and impact of mite infection on mosquito population

    Directory of Open Access Journals (Sweden)

    Atwa A. Atwa

    Full Text Available ABSTRACT During the present study, the host-parasite relationship between mosquitoes and parasitic mites was investigated. The 8954 individuals of male and female mosquitoes belonging to 26 genera: seven each of Aedes and Culex, six of Anopheles and one each of Toxorhynchites, Coquillettidia and Uranotaenia were collected from 200 sites. The male and female mosquitoes were collected from the State of Uttar Pradesh, located at 26.8500° N, 80.9100° E in North India by deploying Carbon dioxide-baited and gravid traps. The intensity of mite's infection, type and number of mites attached to mosquitoes, mite's preference for body parts and host sexes were the parameters used to determine host-parasite relationship. Eight species of mites: Arrenurus acuminatus, Ar. gibberifrons, Ar. danbyensis, Ar. madaraszi, Ar. kenki, Parathyas barbigera, Leptus sp., and Anystis sp., parasitized mosquitoes. Parasitic mites preferred host's thorax for attachment as compared to the head, pre-abdomen or appendages. The present study suggests phoretic relationship between parasitic mites and mosquitoes. Wide occurrence, intensity of infection, parasitic load, and attachment preferences of the mites suggested their positive role in biological control of adult mosquitoes. The present study will set the path of future studies on host-parasite relationships of mites and mosquitoes and define the role of parasitic mites in the biological control of mosquitoes.

  13. Child car seats – a habitat for house dust mites and reservoir for harmful allergens

    Directory of Open Access Journals (Sweden)

    David Clarke

    2015-02-01

    Full Text Available [b]Introduction and objective[/b]. House dust mites produce allergens which can cause or aggravate diseases such as asthma, eczema and rhinitis. The objectives of this study are to quantify typical house dust mite and Der p 1 allergen levels in child car seats, and to determine external variables that may influence mite populations in cars. [b]Materials and Methods[/b]. Dust samples were collected from the child car seats and driver seats of 106 cars using a portable vacuum sampling pump over a two minute sampling period. Mites were counted and identified and results were expressed as mites per gram (mites/g of dust, while Der p 1 content of samples were measured by enzyme-linked immunosorbent assay (ELISA. Questionnaires were completed by participants to identify environmental and behavioural effects on mite populations. Results were analysed using General Linear Model (GLM procedures. [b]Results[/b]. Twelve species of mites, of which nine are known to produce harmful allergens, were recorded from 212 dust samples. Over 80% of drivers’ seats and over 77% of child car seats harboured dust mites with a significant correlation (p = 0.001 between the mites/g of dust and Der p 1 content recovered from each seat. A mean of 53 mites/g of dust per seat was recovered, with a mean Der p 1 level of 1.1µg/g. Over 12% of driver seats and 15% of child car seats contained house dust mite levels sufficient to be risk factors for sensitisation and allergic reactions. [b]Conclusions[/b]. Child car seats and driver seats are habitats to a range of mite species which can be present in sufficient concentrations to cause or aggravate allergen related illnesses in individuals who are genetically predisposed.

  14. Morphological, molecular and cross-breeding analysis of geographic populations of coconut-mite associated predatory mites identified as Neoseiulus baraki: evidence for cryptic species?

    NARCIS (Netherlands)

    N.F. Sourassou; R. Hanna; I. Zannou; J.A.J. Breeuwer; G. de Moraes; M.W. Sabelis

    2012-01-01

    Surveys were conducted in Brazil, Benin and Tanzania to collect predatory mites as candidates for control of the coconut mite Aceria guerreronis Keifer, a serious pest of coconut fruits. At all locations surveyed, one of the most dominant predators on infested coconut fruits was identified as Neosei

  15. Mites (Acari: Trombidiformes) parasitizing mosquitoes (Diptera: Culicidae) in an Atlantic Forest area in southern Brazil with a new mite genus country record.

    Science.gov (United States)

    Dos Santos, Emili Bortolon; Favretto, Mario Arthur; Dos Santos Costa, Samuel Geremias; Navarro-Silva, Mario Antonio

    2016-07-01

    In this study, a total of 4146 culicids collected in an Atlantic Forest area in Paraná state, southern Brazil were examined for the presence of mites. Forty larval Parasitengone mites (Arrenurus spp., Arrenuridae; Durenia spp., Trombellidae; Microtrombidium spp., Microtrombidiidae) parasitized 25 specimens of mosquitoes, with the intensity varying from one to nine mites attached. Most mites were found on Aedes serratus/nubilus, Culex vomerifer, Cx. pedroi and Cx. sacchettae. The overall percentage of parasitized mosquitoes was 0.6 %. The highest intensity of mites encountered was in an individual of Cx. pedroi with nine attached mites. Regarding the attachment site, most mite specimens were attached to the abdomen (n = 25), whereas 15 were located on the thorax. Specimens of Arrenurus spp. were only found on the abdomen of mosquitoes, and the same was observed for Microtrombidium spp., while Durenia spp. attached to both the thorax (n = 15) and abdomen (n = 4). This is the first record for the genus Durenia in Brazil. Additionally, some species of mosquitoes were, for the first time, reported as being parasitized by mites.

  16. Induction of direct and indirect plant responses by jasmonic acid, low spider mite densities, or a combination of jasmonic acid treatment and spider mite infestation

    NARCIS (Netherlands)

    Gols, G.J.Z.; Roosjen, M.; Dijkman, H.; Dicke, M.

    2003-01-01

    Jasmonic acid (JA) and the octadecanoid pathway are involved in both induced direct and induced indirect plant responses. In this study, the herbivorous mite, Tetranychus urticae, and its predator, Phytoseiulus persimilis, were given a choice between Lima bean plants induced by JA or spider mites

  17. Screening low fire blight susceptible Crataegus species for host suitability to hawthorn leaf-curling aphids (Dysaphis spp.).

    Science.gov (United States)

    Bribosia, E; Bylemans, D; Van Impe, G; Migon, M

    2002-01-01

    The group of hawthorn leaf-curling aphids (Dysaphis spp.) hosted by the common hawthorn Crataegus monogyna Jacq. may play an important role in the biological control of the rosy apple aphid, Dysaphis plantaginea (Passerini), by increasing reproduction opportunities for the indigenous hymenopteran parasitoid Ephedrus persicae Froggatt. Unfortunately, most fruitgrowers hesitate to introduce the common hawthorn in their orchards because they fear fire blight infections which may be transmitted by this highly susceptible hawthron species. This potential hazard led us to investigate the suitability to leaf-curling aphids of alternative Crataegus species. As representative for these closely-related aphids, the species Dysaphis apiifolia petroselini (Börner) was used in the trials. Ten Crataegus species characterized by their very low susceptibility to fire blight were examined from two angles. Firstly, aphid sexuals were introduced in autumn onto the different species to verify whether egg laying could take place. Secondly, the development of fundatrices and gall formation were followed the next spring. Although eggs and mature fundatrices could be obtained on almost all species, no fundatrice-hosting galls were recorded in spring. The possible causes of these negative results with respect to the geographical origin of the particular Crataegus species involved in this work are discussed.

  18. ENSO-correlated fluctuations in ocean bottom pressure and wind-stress curl in the North Pacific

    Directory of Open Access Journals (Sweden)

    D. P. Chambers

    2011-07-01

    Full Text Available We examine the magnitude of ENSO-correlated variations in wind-stress curl and ocean bottom pressure in the North Pacific between 1992 until 2010, using satellite observations and model output. Our analysis indicates that while there are significant fluctuations correlated with some El Niño and La Niña events, the correlation is still relatively low. Moreover, the ENSO-correlated variability explains only 50 % of the non-seasonal, low-frequency variance. There are significant residual fluctuations in both wind-stress curl and ocean bottom pressure in the region with periods of 4-years and longer. One such fluctuation began in late 2002 and has been observed by the Gravity Recovery and Climate Experiment (GRACE. Even after accounting for ENSO variations, there is a significant trend in ocean bottom pressure in the region, equivalent to 0.7 ± 0.3 cm yr−1 of sea level from January 2003 until December 2008, which is confirmed with steric-corrected altimetry. Although this low-frequency fluctuation does not appear in an ocean model, we show that the winds used to force the model have a significantly reduced trend that is inconsistent with satellite observations over the same time period.

  19. Genome organization of Tobacco leaf curl Zimbabwe virus, a new, distinct monopartite begomovirus associated with subgenomic defective DNA molecules.

    Science.gov (United States)

    Paximadis, M; Rey, M E

    2001-12-01

    The complete DNA A of the begomovirus Tobacco leaf curl Zimbabwe virus (TbLCZWV) was sequenced: it comprises 2767 nucleotides with six major open reading frames encoding proteins with molecular masses greater than 9 kDa. Full-length TbLCZWV DNA A tandem dimers, cloned in binary vectors (pBin19 and pBI121) and transformed into Agrobacterium tumefaciens, were systemically infectious upon agroinoculation of tobacco and tomato. Efforts to identify a DNA B component were unsuccessful. These findings suggest that TbLCZWV is a new member of the monopartite group of begomoviruses. Phylogenetic analysis identified TbLCZWV as a distinct begomovirus with its closest relative being Chayote mosaic virus. Abutting primer PCR amplified ca. 1300 bp molecules, and cloning and sequencing of two of these molecules revealed them to be subgenomic defective DNA molecules originating from TbLCZWV DNA A. Variable symptom severity associated with tobacco leaf curl disease and TbLCZWV is discussed.

  20. Whitefly-mediated transmission of cotton leaf curl Multan betasatellite: evidence for betasatellite encapsidation in coat protein of helper begomoviruses.

    Science.gov (United States)

    Tabein, S; Behjatnia, S A Akbar; Anabestani, A; Izadpanah, K

    2013-01-01

    Cotton leaf curl Multan betasatellite (CLCuMB) is responsible for symptom expression of a devastating disease of cotton in the Indian subcontinent. CLCuMB depends on helper virus replication-associated protein for its replication and on viral coat protein (CP) for its encapsidation. However, no direct evidence of encapsidation of CLCuMB in viral CP has been available. In the present study, non-viruliferous whiteflies were placed on tomato plants that had been agroinoculated with infectious clones of an Iranian isolate of tomato yellow leaf curl virus (TYLCV-[Ab]) and CLCuMB for an acquisition access period of 72 h and then transferred to healthy tomato seedlings at the 3- to 4-leaf stage. Typical symptoms of TYLCV-[Ab] appeared on inoculated seedlings 30-45 days post-inoculation. The presence of TYLCV-[Ab] and CLCuMB DNAs in symptomatic test plants and viruliferous whiteflies was confirmed by PCR analysis using specific primers and DIG Southern blotting. Furthermore, the possibility of CLCuMB DNA encapsidation in TYLCV-[Ab] CP within infected plants was examined by immunocapture PCR. The results showed that CLCuMB DNA was encapsidated in TYLCV-[Ab] CP. Whitefly-mediated transmission of CLCuMB in the presence of helper virus is additional evidence for encapsidation of CLCuMB by TYLCV-[Ab] CP.

  1. Effect of Activated Charcoal Fibers on the Survival of the House Dust Mite, Dermatophagoides pteronyssinus: A Pilot Study.

    Science.gov (United States)

    Nam, Hae-Seon; Lee, Sun-Hwa; Choi, Young-Jin; Park, Joon-Soo; Cho, Moon-Kyun; Lee, Sang-Han; Crane, Julian; Siebers, Robert

    2012-01-01

    House dust mites produce potent allergens that exacerbate asthma in sensitized patients, whom are recommended to practice allergen avoidance within their home environment. We tested the effect of activated charcoal impregnated fibers on house dust mite survival. One hundred live adult house dust mites (Dermatophagoides pteronyssinus) were added to eight culture dishes preequilibrated at room temperature (n = 4) and 70% humidity (n = 4) containing house dust mite food and active charcoal fibers. At 10 minute intervals, live and dead house dust mites were counted. All house dust mites instantly attached to the activated charcoal fibers and started to shrink almost immediately. There were no live house dust mites present as early as 40 minutes in some dishes while after 190 minutes all house dust mites were dead. In conclusion, activated charcoal fibers, if incorporated into bedding items, have the potential to control house dust mites in the indoor environment.

  2. Explosive resistance training increases rate of force development in ankle dorsiflexors and gait function in adults with cerebral palsy

    DEFF Research Database (Denmark)

    Kirk, Henrik; Geertsen, Svend Sparre; Lorentzen, Jakob

    2016-01-01

    Alterations in passive elastic properties of muscles and reduced ability to quickly generate muscle force contribute to impaired gait function in adults with cerebral palsy (CP). Here, we investigated if 12 weeks of progressive and explosive resistance training (PRT) increases rate of force...... dorsiflexion, plantarflexion, leg press, hamstring curls, abdominal curls and back extension 3 days/week for 12 weeks, with 3 sets per exercise and progressing during the training period from 12-6 RM. RFDdf, 3-D gait analysis, functional performance and ankle joint passive- and reflex-mediated muscle stiffness...

  3. The First Report of Eustigmaeus johnstoni (Acari: Stigmaeidae Parasitic Mite of Phlebotominae Sand Flies from Iran.

    Directory of Open Access Journals (Sweden)

    Mehdi Badakhshan

    2013-06-01

    Full Text Available Stigmaeids mites have been recorded only on Phlebotominae sand flies up to now. Five species of Eustigmaeus, and three of Stigmaeus were reported on infested sandflies in different country up to the present.Sand flies collection was done using CDC light trap and sticky paper. The mites were isolated from infested specimens, mounted in Puri's medium and identified using reliable keys.A mite infested Phlebotomus papatasi was observed during a study on sandflies of one of the southern provinces of Iran, near to the Persian Gulf. Several scars resulting from mite attachment were found on abdominal tergites of this female sand fly. The mites were identified as Eustigmaeus johnstoni.This parasitic mite is one of the eyeless species, which has a great distribution over the world, reported from Tunisia, Saudi Arabia, Pakistan, Yemen, Cyprus and Palestine. But, this is the first record of this species from Iran.

  4. The First Report of Eustigmaeus Johnstoni (Acari: Stigmaeidae Parasitic Mite of Phlebotominae Sand Flies from Iran

    Directory of Open Access Journals (Sweden)

    Mehdi Badakhshan

    2013-03-01

    Full Text Available Background: Stigmaeids mites have been recorded only on Phlebotominae sand flies up to now. Five species of Eustigmaeus, and three of Stigmaeus were reported on infested sandflies in different country up to the present.Methods: Sand flies collection was done using CDC light trap and sticky paper. The mites were isolated from in­fested specimens, mounted in Puri’s medium and identified using reliable keys.Results: A mite infested Phlebotomus papatasi was observed during a study on sandflies of one of the southern provinces of Iran, near to the Persian Gulf. Several scars resulting from mite attachment were found on abdominal tergites of this female sand fly. The mites were identified as Eustigmaeus johnstoni.Conclusion: This parasitic mite is one of the eyeless species, which has a great distribution over the world, reported from Tunisia, Saudi Arabia, Pakistan, Yemen, Cyprus and Palestine. But, this is the first record of this species from Iran.

  5. Natural biological control of pest mites in Brazilian sun coffee agroecosystems.

    Science.gov (United States)

    Teodoro, Adenir V; Sarmento, Renato A; Rêgo, Adriano S; da Graça S Maciel, Anilde

    2010-06-01

    Coffee is one of the leading commodities in tropical America. Although plantations are usually established under a canopy of trees in most producing countries in the region, Brazilian coffee is mostly produced under full sun conditions. Such simple, single-crop agroecosystems with intensive agrochemical inputs often suffer with pests like mites. Predatory mites of the family Phytoseiidae are the main natural enemies associated with pest mites in the field. However, these beneficial arthropods struggle to survive in intensive agroecosystems such as coffee monocultures due to unfavorable microclimatic conditions, widespread pesticide use, and lack of alternative food (pollen, nectar). Conservation biological control uses a range of management strategies to sustain and enhance populations of indigenous natural enemies such as predatory mites. We discuss here conservation biological control as a strategy to improve biological control of pest mites by native predatory mites in Brazilian coffee monocultures as well as some related patents.

  6. Activated charcoal suppresses breeding of the house dust mite, Dermatophagoides pteronyssinus, in culture.

    Science.gov (United States)

    Nam, Hae-Seon; Siebers, Robert; Lee, Sun-Hwa; Kim, Sung-Ho; Lee, Sang-Han; Crane, Julian

    2007-04-01

    House dust mite sensitized asthmatics are advised to practice allergen avoidance. Charcoal pillows are used in Korea with unsubstantiated claims regarding their efficacy in alleviating asthma symptoms. We tested the effects of activated charcoal on breeding of house dust mites in culture. Twenty live adult house dust mites (Dermatophagoides pteronyssinus) were inoculated, 10 replicates, on culture media containing 0%, 1%, 3%, 5%, 10%, and 20% activated charcoal and incubated at 25 degrees C and a relative humidity of 75%. After four weeks, the mean numbers of live house dust mites were 286, 176, 46, 16, 7, and 0 for the 0%, 1%, 3%, 5%, 10%, and 20% charcoal-containing culture media, respectively. Thus, activated charcoal suppresses breeding of house dust mites and offers a new promising method for house dust mite control.

  7. Catalogue of snout mites (Acariformes: Bdellidae) of the world.

    Science.gov (United States)

    Hernandes, Fabio A; Skvarla, Michael J; Fisher, J Ray; Dowling, Ashley P G; Ochoa, Ronald; Ueckermann, Edward A; Bauchan, Gary R

    2016-08-17

    Bdellidae (Trombidiformes: Prostigmata) are moderate to large sized predatory mites that inhabit soil, leaves, leaf litter, and intertidal rocks. They are readily recognized by an elongated, snout-like gnathosoma and by elbowed pedipalps bearing two (one in Monotrichobdella Baker & Balock) long terminal setae. Despite being among the first mites ever described, with species described by Carl Linnaeus, the knowledge about bdellids has never been compiled into a taxonomic catalogue. Here we present a catalogue listing 278 valid species; for each species we include distribution information, taxonomic literature, and type depository institutions. The genus Rigibdella Tseng, 1978 is considered a junior synonym of Cyta von Heyden, 1826, and Bdellodes Oudemans, 1937 is considered a junior synonym of Odontoscirus Tohr, 1913. Illustrated keys to subfamilies and genera are presented, as well as keys to species of each genus.

  8. Identification and Characterization of Seven Glutathione S-Transferase Genes from Citrus Red Mite, Panonychus citri (McGregor

    Directory of Open Access Journals (Sweden)

    Chong-Yu Liao

    2013-12-01

    Full Text Available The citrus red mite, Panonychus citri (McGregor, is a global citrus pest, and has developed severe resistance to several types of acaricides. However, the molecular mechanisms of resistance in this mite remain unknown. In this study, seven full-length cDNAs encoding glutathione S-transferases (GSTs genes were identified and characterized in P. citri. The effects of pyridaben and fenpropathrin exposure on the expression of these genes were also investigated. Phylogenetic analysis revealed that the seven GSTs genes in P. citri cloned in this study belong to three different cytosolic classes, including four in mu, two in delta and one in zeta. Among these seven GSTs genes, the relative expression level of PcGSTm1 was significantly higher in adult than in the other life stages (egg, larvae and nymph. Compared with the control, the mRNA levels of the seven GST genes did not change significantly following exposure to pyridaben at LC10. However, RT-qPCR results showed that, when exposed to LC10 of fenpropathrin, six GSTs gene (PcGSTm1, PcGSTm3, PcGSTm4, PcGSTd1, PcGSTd2 and PcGSTz1 transcripts increased in a time-dependent manner. This is the first insight into the molecular characteristics of GSTs gene cDNAs in P. citri. The elevated GSTs gene transcripts following exposure to fenpropathrin might be one of the mechanisms involved in detoxification of this acaricide.

  9. Silicas for control of the poultry red mite Dermanyssus gallinae

    OpenAIRE

    Maurer, Veronika; Perler, Erika

    2006-01-01

    Control of the poultry red mite Dermanyssus gallinae is a challenge for organic as well as conventional egg producers. In organic agriculture, control should be attempted by mechanically acting substances (e.g. oils or diatomaceous earth), before acaricides are applied. Diatomaceous earth (DE) without acaricides was at least as effective as DE supplemented with pyrethrum or essential oils and a liquid formulation of silica in vitro. In on farm experiments, DE was effective during a limited pe...

  10. Cita sin límites con Emilio Prados

    OpenAIRE

    2012-01-01

    Con motivo del 50 aniversario de la muerte en el exilio del poeta Emilio Prados, nacido en Málaga y miembro de la Generación del 27, hacemos una valoración y un recorrido por su obra poética desde la atalaya de su último libro inconcluso, Cita sin límites. Este libro se constituye en un diario de sus últimos días y es recapitulativo de toda su obra

  11. Hormonal-Pheromonal Interrelationships in Ticks and Parasitic Mites.

    Science.gov (United States)

    1986-12-01

    on development and reproduc- tion were also studied. In addition, pheromones in the poultry mite (Dermanyssus gallinae) and background studies dealing...and nymphal responses. IBID 20: Silverstein, R.M., J.R. West, G.M. Khalil, and D.E. Sonenshine. Occurrence of 2,6-dichlorophenol in the hard ticks...cells growing in suspension were pelleted by gentle centrifugation, fixed, osmi- cated, and dehydrated as described aDove. The cells’were infiltrated

  12. Reproductive biology of varroa mites in colonies of Africanized honey bees

    OpenAIRE

    Calderon Fallas, R.A.

    2009-01-01

    We investigated the reproductive biology of V. destructor in Africanized honeybees (AHB) in Central American conditions, specifically in Costa Rica. Attention was paid to mite fertility and production of viable female mites in worker and drone brood cells. Other reproduction parameters, like fecundity, production of only immature offspring, production of only female or only male offspring and no reproduction at all are discussed. Furthermore, results on mite population dynamics and its influe...

  13. First report of the citrus Hindu mite, Schizotetranychus hindustanicus (Hirst) (Prostigmata: Tetranychidae), in Brazil.

    Science.gov (United States)

    Navia, Denise; Marsaro, Alberto L

    2010-01-01

    The citrus Hindu mite, Schizotetranychus hindustanicus (Hirst), is reported for the first time in Brazil and for the second time in South America. Mite specimens were collected from citrus in the municipality of Boa Vista, State of Roraima, northern Brazil. Symptoms associated with S.hindustanicus infestations on citrus are described. The importance of avoiding dissemination of this mite to the main citrus production areas in Brazil is discussed.

  14. Comparative morphological analysis of apple blister mite, Eriophyes mali Nal., a new pest in Serbia

    OpenAIRE

    2014-01-01

    The apple blister mite, Eriophyes mali Nalepa, 1926 (Acari: Prostigmata: Eriophyoidea), has been recently found in Serbia as a new pest of apple. The history of its research, the results of a morphological analysis and degree of infestation are presented. A comparison of the main morphological features of mites from different populations of remote geographical origin has shown that the apple blister mite from Serbia is most similar to another European popul...

  15. Niche Partitioning of Feather Mites within a Seabird Host, Calonectris borealis.

    Directory of Open Access Journals (Sweden)

    Laura M Stefan

    Full Text Available According to classic niche theory, species can coexist in heterogeneous environments by reducing interspecific competition via niche partitioning, e.g. trophic or spatial partitioning. However, support for the role of competition on niche partitioning remains controversial. Here, we tested for spatial and trophic partitioning in feather mites, a diverse and abundant group of arthropods. We focused on the two dominant mite species, Microspalax brevipes and Zachvatkinia ovata, inhabiting flight feathers of the Cory's shearwater, Calonectris borealis. We performed mite counts across and within primary and tail feathers on free-living shearwaters breeding on an oceanic island (Gran Canaria, Canary Islands. We then investigated trophic relationships between the two mite species and the host using stable isotope analyses of carbon and nitrogen on mite tissues and potential host food sources. The distribution of the two mite species showed clear spatial segregation among feathers; M. brevipes showed high preference for the central wing primary feathers, whereas Z. ovata was restricted to the two outermost primaries. Morphological differences between M. brevipes and Z. ovata support an adaptive basis for the spatial segregation of the two mite species. However, the two mites overlap in some central primaries and statistical modeling showed that Z. ovata tends to outcompete M. brevipes. Isotopic analyses indicated similar isotopic values for the two mite species and a strong correlation in carbon signatures between mites inhabiting the same individual host suggesting that diet is mainly based on shared host-associated resources. Among the four candidate tissues examined (blood, feather remains, skin remains and preen gland oil, we conclude that the diet is most likely dominated by preen gland oil, while the contribution of exogenous material to mite diets is less marked. Our results indicate that ongoing competition for space and resources plays a

  16. Niche Partitioning of Feather Mites within a Seabird Host, Calonectris borealis

    Science.gov (United States)

    Stefan, Laura M.; Gómez-Díaz, Elena; Elguero, Eric; Proctor, Heather C.; McCoy, Karen D.; González-Solís, Jacob

    2015-01-01

    According to classic niche theory, species can coexist in heterogeneous environments by reducing interspecific competition via niche partitioning, e.g. trophic or spatial partitioning. However, support for the role of competition on niche partitioning remains controversial. Here, we tested for spatial and trophic partitioning in feather mites, a diverse and abundant group of arthropods. We focused on the two dominant mite species, Microspalax brevipes and Zachvatkinia ovata, inhabiting flight feathers of the Cory’s shearwater, Calonectris borealis. We performed mite counts across and within primary and tail feathers on free-living shearwaters breeding on an oceanic island (Gran Canaria, Canary Islands). We then investigated trophic relationships between the two mite species and the host using stable isotope analyses of carbon and nitrogen on mite tissues and potential host food sources. The distribution of the two mite species showed clear spatial segregation among feathers; M. brevipes showed high preference for the central wing primary feathers, whereas Z. ovata was restricted to the two outermost primaries. Morphological differences between M. brevipes and Z. ovata support an adaptive basis for the spatial segregation of the two mite species. However, the two mites overlap in some central primaries and statistical modeling showed that Z. ovata tends to outcompete M. brevipes. Isotopic analyses indicated similar isotopic values for the two mite species and a strong correlation in carbon signatures between mites inhabiting the same individual host suggesting that diet is mainly based on shared host-associated resources. Among the four candidate tissues examined (blood, feather remains, skin remains and preen gland oil), we conclude that the diet is most likely dominated by preen gland oil, while the contribution of exogenous material to mite diets is less marked. Our results indicate that ongoing competition for space and resources plays a central role in

  17. The repellent and persistent toxic effects of essential oils against the poultry red mite, Dermanyssus gallinae.

    Science.gov (United States)

    Nechita, I S; Poirel, M T; Cozma, V; Zenner, L

    2015-12-15

    The economic impact of the poultry red mite, Dermanyssus gallinae, the lack of new acaricides, the occurrence of resistance and tighter legislation have all led to the need to find new ways to control this pest. One promising alternative method of control focuses on employing repellent and/or toxic effects of selected plant essential oils against D. gallinae. Ten essential oils (basil, thyme, coriander, eucalyptus, lavender, lemon, fir tree, oregano, mint, and juniper) were tested for the persistence of toxic and repellent effects. In filter-paper toxicity bioassays against D. gallinae, the best results were observed for lavender (more than 97% mortality after 48 and 72 h) and thyme (84% at 72 h) at a dose of 0.12 mg/cm(2). In addition, two oils showed significant persistent toxic effects 15 and 30 days post application to filter papers. Thyme was the most effective (100% mortality at 72 h), followed by lavender (nearly 80% mortality after 72 h). Out of the ten oils tested for their repellent effect, thyme was the strongest, with nearly 80% of the tested area avoided by mites; oregano caused a 60% avoidance and lavender exhibited an effect close to 40%. All other oils exhibited a repellent effect of less than 30%. None of the experiments showed a repellent effect for HM (commercial alimentary oil) or negative controls. We found that the thyme and lavender essential oils exhibited promising results when tested in vitro for toxic and repellent effects against D. gallinae; thus, we suggest that future experiments focus on in vivo tests using these oils in farm units.

  18. Mite-control activities of active constituents isolated from Pelargonium graveolens against house dust mites.

    Science.gov (United States)

    Jeon, Ju-Hyun; Kim, Hyung-Wook; Kim, Min-Gi; Lee, Hoi-Seon

    2008-10-01

    The mite-control activities of materials obtained from Pelargonium graveolens oil against Dermatophagoides farinae and D. pteronyssinus were examined using an impregnated fabric disk bioassay and were compared with those shown by commercial benzyl benzoate and N,N-diethylm- toluamide (DEET). Purification of the biologically active constituents from P. graveolens oil was done by silica gel chromatography and high performance liquid chromatography. The structures of the active components were analyzed by EI/MS, (1)H-NMR, (13)C-NMR, (1)H-(13)C COSYNMR, and DEPT-NMR spectra, and were identified as geraniol (C(10)H(18)O, MW 154.25, trans-3,7-dimethyl-2,6- octadien-1-ol) and beta-citronellol (C(10)H(20)O, MW 156.27, 3,7-dimethyl-6-octen-1-ol). Based on the LD50 values, the most toxic compound was geraniol (0.26 microg/cm(2)), followed by beta-citronellol (0.28 microg/cm(2)), benzyl benzoate (10.03 microg/ cm(2)), and DEET (37.12 microg/cm(2)) against D. farinae. In the case of D. pteronyssinus, geraniol (0.28 microg/cm(2)) was the most toxic, followed by beta-citronellol (0.29 microg/cm(2)), benzyl benzoate (9.58 microg/cm(2)), and DEET (18.23 microg/cm(2)). These results suggest that D. farinae and D. pteronyssinus may be controlled more effectively by the application of geraniol and beta-citronellol than benzyl benzoate and DEET. Furthermore, geraniol and beta-citronellol isolated from P. graveolens could be useful for managing populations of D. farinae and D. pteronyssinus.

  19. [Sensitization to house dust and storage mites in allergic adults from the South of Mexico city].

    Science.gov (United States)

    Ramírez-Heredia, Jennifer; Oífarrill-Romanillos, Patricia María; Guidos-Fogelbach, Guillermo; Miyagui-Nakamura, Roberto Ken; Segura-Méndez, Nora Hilda

    2013-01-01

    Mites are the most common cause of respiratory allergy. Sensitization to house dust mites is estimated at 30%. Families Euroglyphus and Dermatophagoides, are the most important. Recently, storage mites, from the families Acaridae and Glyciphagidae, have become more important as a cause of allergic respiratory diseases. The aim of this study was to identify sensitization to house dust and storage mites by skin tests in adult patients with allergic respiratory diseases. This is a descriptive study in patients with asthma and/or allergic rhinitis, with the approval of the local research committee 2009-3601-46. Patients underwent skin prick tests, with seven standardized extracts of mites (IPI ASACR). The results were analyzed with descriptive statistics. A total of 150 patients, 109 women and 41 men, with an average age 31 years (±11) were studied. The more common allergic diseases in this group of patients were: asthma and rhinitis 72 and 26%, respectively, and asthma plus rhinitis 3.2%. Positive skin tests for Dermatophagoides pteronyssinus and Dermatophagoides farinae were 82.1% 71.5%, respectively, and for storage mites: A. siro 51.7%, Tyrophagus 47.4%, Glycyphagus 47.7%, B. tropicalis 39.7% and Lepidoglyphus 39.1%. Storage mites produced greater sensitization than house dust mites, 32% vs 10%. The results show that adult patients with respiratory allergy, in southern Mexico City, have a higher rate of sensitization to storage mites than the one reported in the literature.

  20. House-dust mites in our homes are a contamination from outdoor sources

    DEFF Research Database (Denmark)

    Hallas, Thorkil E.

    2010-01-01

    Avoidance advices for house-dust mite sensitized persons are currently based upon the idea, that the mites (Dermatophagoides spp.) are part of the indoor fauna. A closer look at development stages in the house-dust samples shows, however, that only the mites' active stages are present there and t...... no effect of avoidance measures. The verification of the entire hypothesis or part of it may have great impact on the management of the disease house-dust mite allergy.......Avoidance advices for house-dust mite sensitized persons are currently based upon the idea, that the mites (Dermatophagoides spp.) are part of the indoor fauna. A closer look at development stages in the house-dust samples shows, however, that only the mites' active stages are present...... there and that the stages between them, the inactive moulting stages, are absent. Therefore the mites probably do not carry out their life cycles in our dwellings, but are more likely contaminations from the open. Findings of low level concentrations can be explained by mites coming from outdoors and sedimented...

  1. [The relationship between the skin allergy test and house dust mites].

    Science.gov (United States)

    Atambay, Metin; Aycan, Ozlem M; Yoloğlu, Saim; Karaman, Ulkü; Daldal, Nilgün

    2006-01-01

    Since 1960 it has been known that house dust mites are related to allergy and that they cause pulmonary tract diseases. There are various house dust mites and among these Dermatophagoides pteronyssinus (Trouessart, 1897) and Dermatophagoides farinae (Hughes, 1961) are best known with regard to their medical importance and morphological characteristics. Skin tests are used to determine the role of mites in allergic diseases. The tests are performed by using D. pteronyssinus and D. farinae antigens. In order to study, the concordance between the skin test results and the presence of house dust mites, dust samples from the houses of 49 patients diagnosed with allergic diseases who underwent skin tests were taken to investigate the presence of mites in dust. House dust mites were determined in 23 (46.3%) of the houses. Mites were found in the houses of 15 (50.0%) of 30 patients with positive skin test results and 8 (42.0%) of 19 patients with negative skin test results. There was no significant difference between the skin test positivity and negativity in the presence of house dust mites (P>0,005). In conclusion, we thought that it was necessary to evaluate the presence of mites in the houses of people who have allergic symptoms even if they had negative skin test results.

  2. Mange mites of sheep and goats in selected sites of Eastern Amhara region, Ethiopia.

    Science.gov (United States)

    Seid, Kibeb; Amare, Sisay; Tolossa, Yacob Hailu

    2016-03-01

    A cross sectional study of small ruminant mange mites was conducted from November 2011 to April 2012 on a total of 324 sheep and 680 goats, to determine the prevalence of mange mites in sheep and goats, identifying the major species of mite and to determine the potential risk factors significantly predicting the disease. The result showed an overall mange mite prevalence of 7.5 % (95 % CI 5.5-9.5) in goats and 1.2 % (95 % CI 0.5-1.9) in sheep. The mites identified were Sarcoptes and Demodex in goats and Sarcoptes and Psoroptes in sheep. The prevalence of mange mites was significantly higher in goats than in sheep (χ(2) = 16.636, P = 0.000). There was higher prevalence of mange mites in poor body condition than good body condition sheep and goats and the difference was statistically significant (χ(2) = 5.513, P = 0.019 in sheep and χ(2) = 141.85, P = 0.000 in goats). But age and sex of the host animals and agro climates were not statistically significant predictors of prevalence of mange mite. This study demonstrated that mange mites are among the major parasitic health problems of shoats in Eastern Amhara region that require urgent control intervention.

  3. Contrasting diversity dynamics of phoretic mites and beetles associated with vertebrate carrion.

    Science.gov (United States)

    Barton, Philip S; Weaver, Haylee J; Manning, Adrian D

    2014-05-01

    Carrion is an ephemeral and nutrient-rich resource that attracts a diverse array of arthropods as it decomposes. Carrion-associated mites often disperse between animal carcasses using phoresy, the transport of one species by another. Yet few studies have contrasted the dynamics of mite assemblages with other insect taxa present at carrion. We examined and compared the changes in abundance, species richness and composition of mite and beetle assemblages sampled at kangaroo carcasses in a grassy eucalypt woodland at four different times over a 6-month period. We found that the majority of mites were phoretic, with the mesostigmatid genera Uroseius (Uropodidae), Macrocheles (Macrochelidae) and Parasitus (Parasitidae) the most abundant taxa (excluding astigmatid mites). Abundance and richness patterns of mites and beetles were very different, with mites reaching peak abundance and richness at weeks 6 and 12, and beetles at weeks 1 and 6. Both mites and beetles showed clear successional patterns via changes in species presence and relative abundance. Our study shows that mesostigmatid mite assemblages have a delay in peak abundance and richness relative to beetle assemblages. This suggests that differences in dispersal and reproductive traits of arthropods may contribute to the contrasting diversity dynamics of carrion arthropod communities, and further highlights the role of carrion as a driver of diversity and heterogeneity in ecosystems.

  4. Control of the northern fowl mite on inanimate objects by fumigation: laboratory studies.

    Science.gov (United States)

    Beerwinkle, K R; Devaney, J A

    1983-01-01

    Laboratory studies were conducted to determine the efficacies of phosphine, methyl bromide, and sulfur dioxide as fumigants for the northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), on inanimate objects. We were able to demonstrate that either methyl bromide or sulfur dioxide could kill all physiological forms of mites within 24 hr, which would be desirable for field use. Prosphine gas, released from Phostoxin pellets, had an LD95 of 18 hr for motile forms of the mites; however, it took 30 hr to kill the mite eggs. Therefore, it would be an unsuitable fumigant for practical field usage.

  5. Myrmecophilous pygmephoroid mites (Acari: Pygmephoroidea) associated with Lasius flavus (Hymenoptera: Formicidae) in Russia.

    Science.gov (United States)

    Khaustov, Alexander A

    2015-11-19

    Twenty four species of pygmephoroid mites (Acari: Pygmephoroidea: Neopygmephoridae, Scutacaridae, Microdispidae) are recorded from the ant Lasius flavus (Fabricius) or from its nests from Western Siberia and Crimea. Four of them of the genus Scutacarus Gros, 1845 (Acari: Scutacaridae), S. insolitus sp. nov., S. heterotrichus sp. nov., S. moseri sp. nov. and S. sibiriensis sp. nov. are described as new for science. Four species of scutacarid mites are recorded for the first time in Russia. The comparison of pygmephoroid mite communities associated with Lasius flavus from Crimean and West Siberian populations and notes on phoresy of pygmephoroid mites on ants are provided.

  6. Geostatistics as a tool to study mite dispersion in physic nut plantations.

    Science.gov (United States)

    Rosado, J F; Picanço, M C; Sarmento, R A; Pereira, R M; Pedro-Neto, M; Galdino, T V S; de Sousa Saraiva, A; Erasmo, E A L

    2015-08-01

    Spatial distribution studies in pest management identify the locations where pest attacks on crops are most severe, enabling us to understand and predict the movement of such pests. Studies on the spatial distribution of two mite species, however, are rather scarce. The mites Polyphagotarsonemus latus and Tetranychus bastosi are the major pests affecting physic nut plantations (Jatropha curcas). Therefore, the objective of this study was to measure the spatial distributions of P. latus and T. bastosi in the physic nut plantations. Mite densities were monitored over 2 years in two different plantations. Sample locations were georeferenced. The experimental data were analyzed using geostatistical analyses. The total mite density was found to be higher when only one species was present (T. bastosi). When both the mite species were found in the same plantation, their peak densities occurred at different times. These mites, however, exhibited uniform spatial distribution when found at extreme densities (low or high). However, the mites showed an aggregated distribution in intermediate densities. Mite spatial distribution models were isotropic. Mite colonization commenced at the periphery of the areas under study, whereas the high-density patches extended until they reached 30 m in diameter. This has not been reported for J. curcas plants before.

  7. [Mites associated to the Coleopteran Passalus cognatus (Coleoptera:Passalidae) from Los Tuxtlas, Veracruz, Mexico].

    Science.gov (United States)

    Villegas-Guzmán, Gabriel A; Pérez, Tila M; Reyes-Castillo, Pedro

    2008-09-01

    There are few records of mites associated with the tropical coleopterans of Mexico. We examined 35 passalid beetles (bessbugs) Passalus cognatus from Los Tuxtlas region in Veracruz State, Mexico. Twenty of them had a total of 245 mites (representing eight species, eight genera, eight families and three suborders). The most abundant species were Uroobovella californiana Wisniewski & Hirschmann (35%), Euzercon hyatti Hunter & Rosario (20%), and Uropoda sp. (17.5%). The preferred attachment areas were the coxae; followed by the mesosternum and the humeri. Each beetle had 1 to 40 mites (average: 12); and we found 1-4 mite species per beetle.

  8. Diversity and significance of eriophyoid mites (Acari: Eriophyoidea associated with coniferous trees in Poland: a review

    Directory of Open Access Journals (Sweden)

    Kiedrowicz Agnieszka

    2016-06-01

    Full Text Available Among the approximately 200 eriophyoid mite species associated with coniferous trees worldwide, 33 species (of the families Eriophyidae and Phytoptidae infest conifers in Poland, and 24 of them can cause visible feeding symptoms. In this paper we discuss the importance of eriophyoid mites to coniferous plants in Poland and their potential impact on the decorative value of ornamental plants. We emphasize the general lack of knowledge about the diversity of eriophyoid mites associated with coniferous trees and its role in the management and control of this economically important mite group.

  9. Mites (Acari Associated with the Desert Seed Harvester Ant, Messor pergandei (Mayr

    Directory of Open Access Journals (Sweden)

    Kaitlin A. Uppstrom

    2011-01-01

    Full Text Available Mites (Acari associated with the seed harvester ant Messor pergandei were investigated in the Sonoran desert of Arizona. At least seven representatives of the mite genera Armacarus, Lemanniella, Petalomium, Forcellinia, Histiostoma, Unguidispus, and Cosmoglyphus are phoretically associated with M. pergandei. Most of these morphospecies show preference for specific phoretic attachment sites and primarily use female alates rather than male alates for dispersal. Five mite morphospecies were found in low numbers inhabiting the chaff piles: Tydeidae sp., Procaeculus sp., Anystidae sp., Bakerdania sp., and Tetranychidae sp. The phoretic Petalomium sp. was observed consuming fungus growing on a dead queen, but the roles of the other mite species remain mostly unresolved.

  10. [Evolution of parasitism in mammal-associated mites of the group Psoroptidia (Acari:Astigmata)].

    Science.gov (United States)

    Bochkov, A V

    2011-01-01

    Host-parasite relationships of mammals and astigmatan mites (Acariformes: Astigmata) belonging to the parvorder Psoroptidia are analyzed. The absolute majority of mammal-associated psoroptidians belongs to the paraphyletic superfamily Sarcoptoidea. Mites of the family complex Psoroptidae (Lobalgidae, Psoroptidae, and Paracoroptinae) shifted from birds to placental mammals independently from each other. Mites of the family complex Sarcoptidae, including all other sarcoptoid families, derived from the common stalk of Psoroptidia independently from the Psoroptid complex. Mites of the sarcoptid complex shifted from nidicoly in mammalian nests to the permanent parasitism on these hosts. They are widely represented on both marsupial and placental mammals and are absent on Monotremata.

  11. Immunoinformatics and Similarity Analysis of House Dust Mite Tropomyosin

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Ranjbar

    2015-10-01

    Full Text Available Background: Dermatophagoides farinae and Dermatophagoides pteronyssinus are house dust mites (HDM that they cause severe asthma and allergic symptoms. Tropomyosin protein plays an important role in mentioned immune and allergic reactions to HDMs. Here, tropomyosin protein from Dermatophagoides spp. was comprehensively screened in silico for its allergenicity, antigenicity and similarity/conservation.Materials and Methods: The amino acid sequences of D. farinae tropomyosin, D. pteronyssinus and other mites were retrieved. We included alignments and evaluated conserved/ variable regions along sequences, constructed their phylogenetic tree and estimated overall mean distances. Then, followed by with prediction of linear B-cell epitope based on different approaches, and besides in-silico evaluation of IgE epitopes allergenicity (by SVMc, IgE epitope, ARPs BLAST, MAST and hybrid method. Finally, comparative analysis of results by different approaches was made.Results: Alignment results revealed near complete identity between D. farina and D. pteronyssinus members, and also there was close similarity among Dermatophagoides spp. Most of the variations among mites' tropomyosin were approximately located at amino acids 23 to 80, 108 to 120, 142 to 153 and 220 to 230. Topology of tree showed close relationships among mites in tropomyosin protein sequence, although their sequences in D. farina, D. pteronyssinus and Psoroptes ovis are more similar to each other and clustered. Dermanyssus gallinae (AC: Q2WBI0 has less relationship to other mites, being located in a separate branch. Hydrophilicity and flexibility plots revealed that many parts of this protein have potential to be hydrophilic and flexible. Surface accessibility represented 7 different epitopes. Beta-turns in this protein are with high probability in the middle part and its two terminals. Kolaskar and Tongaonkar method analysis represented 11 immunogenic epitopes between amino acids 7-16. From

  12. Population growth of Varroa destructor (Acari: Varroidae) in honey bee colonies is affected by the number of foragers with mites.

    Science.gov (United States)

    DeGrandi-Hoffman, Gloria; Ahumada, Fabiana; Zazueta, Victor; Chambers, Mona; Hidalgo, Geoffrey; deJong, Emily Watkins

    2016-05-01

    Varroa mites are a serious pest of honey bees and the leading cause of colony losses. Varroa have relatively low reproductive rates, so populations should not increase rapidly, but often they do. Other factors might contribute to the growth of varroa populations including mite migration into colonies on foragers from other hives. We measured the proportion of foragers carrying mites on their bodies while entering and leaving hives, and determined its relationship to the growth of varroa populations in those hives at two apiary sites. We also compared the estimates of mite population growth with predictions from a varroa population dynamics model that generates estimates of mite population growth based on mite reproduction. Samples of capped brood and adult bees indicated that the proportion of brood cells infested with mites and adult bees with phoretic mites was low through the summer but increased sharply in the fall especially at site 1. The frequency of capturing foragers with mites on their bodies while entering or leaving hives also increased in the fall. The growth of varroa populations at both sites was not significantly related to our colony estimates of successful mite reproduction, but instead to the total number of foragers with mites (entering and leaving the colony). There were more foragers with mites at site 1 than site 2, and mite populations at site 1 were larger especially in the fall. The model accurately estimated phoretic mite populations and infested brood cells until November when predictions were much lower than those measured in colonies. The rapid growth of mite populations particularly in the fall being a product of mite migration rather than mite reproduction only is discussed.

  13. House-dust mite and mite-and pet-allergens in indoor environment; Dani oyobi dani-allergen, pet-allergen no jittai

    Energy Technology Data Exchange (ETDEWEB)

    Irie, T. [Shinshu Univ., Matsumoto, Nagano (Japan)

    1998-05-31

    In this paper, the actual state of mite and mite-allergen, and the actual state of pet-allergen that the researches thereof proceed gradually in recent years are described. The following findings are obtained as the results of the actual state investigations. In respect to the mite-allergen, airborne mite, particularly I with high allergen activity shows high concentration from fall to winter. The reasons thereof are considered from two aspects, I.e., the fragmentation and suspension of mite-allergen, and the decrease of ventilation frequency, while it can also be explained from a fact that the fit of infantile asthma is most frequent during a period from October to November. Mite-allergen contained in futon dust is about 10 times more than that contained in floor dust. In respect to pet-allergen, although the indoor accumulative amount and airborne concentration of main pet-allergen such as cat-, and dog-allergen varies greatly depending on whether pet is kept indoor or outdoor, the quantities of dog- and cat-allergen are almost of the same order, but 2 to 3-order higher than the quantity of mite-allergen. 9 refs., 9 figs.

  14. Predation on the lizard Polychrus acutirostris (Squamata, Polychrotidae) by the curl-crested jay Cyanocorax cristatellus (Aves, Corvidae) in the Cerrado of Central Brazil

    OpenAIRE

    Frederico Gustavo Rodrigues França; Vívian da Silva Braz

    2009-01-01

    Predation on lizards is difficult to observe in nature. Here, we report for the first time an act of predation on the lizard Polychrus acutirostris by the Curl-crested Jay Cyanocorax cristatellus in a Cerrado area of the Chapada dos Veadeiros National Park, central Brazil, thus increasing knowledge of the diet of this bird species.

  15. Predation on the lizard Polychrus acutirostris (Squamata, Polychrotidae by the curl-crested jay Cyanocorax cristatellus (Aves, Corvidae in the Cerrado of Central Brazil

    Directory of Open Access Journals (Sweden)

    Frederico Gustavo Rodrigues França

    2009-09-01

    Full Text Available Predation on lizards is difficult to observe in nature. Here, we report for the first time an act of predation on the lizard Polychrus acutirostris by the Curl-crested Jay Cyanocorax cristatellus in a Cerrado area of the Chapada dos Veadeiros National Park, central Brazil, thus increasing knowledge of the diet of this bird species.

  16. Field evaluation of yield effects on the U.S.A. heirloom sweet potato cultivars infected by sweet potato leaf curl virus

    Science.gov (United States)

    The incidence of Sweet potato leaf curl virus (SPLCV), a Begomovirus, infection of sweetpotato Ipomoea batatas (L.) Lam. (Convolvulaceae) in South Carolina, USA has increased rapidly in recent years. This is likely due to the use of infected propagating materials and the increasing population of it...

  17. Efficient Regeneration and Selection of Virus-free Sweetpotato Plants from Sweet Potato Leaf Curl Virus Infected Materials and Their Effects on Yields in Field Trials

    Science.gov (United States)

    Sweet potato leaf curl virus (SPLCV) is an emerging virus disease in sweetpotato (Ipomoea batata) in the U.S. The incidence of SPLCV infection on sweetpotato increased dramatically in recent years due to the explosion of whitefly, Bemisia tabaci (Gennadius) populations. Among several sweetpotato v...

  18. Field efficacy of phoxim 50% (ByeMite) against the poultry red mite Dermanyssus gallinae in battery cages stocked with laying hens.

    Science.gov (United States)

    Meyer-Kühling, Borris; Pfister, Kurt; Müller-Lindloff, Jürgen; Heine, Josef

    2007-07-20

    Infestations with the poultry red mite Dermanyssus gallinae represent a major ectoparasite problem in poultry and can affect egg layers worldwide. There is presently a lack of an ectoparasiticide in Europe for poultry which can assure a 0-day withholding period for eggs. In this study, ByeMite (phoxim 50%, Bayer HealthCare, Animal Health Division) was administered to treat a D. gallinae infestation in a poultry house stocked with egg-laying hens kept in a cage system. A layer house was sprayed twice within a 7-day interval using a solution containing 2000 ppm phoxim and a similar layer house was used as an untreated control unit. Specially developed D. gallinae traps made of cardboard were used to assess the mite density in both layer houses during a 49-day period after the treatment. In order to collect mites, the traps were placed on days--1, 2, 6, 9, 13, 20, 34 and 48 and always removed after 24 h. The collected mites were counted and differentiated according to their developmental stage (mite eggs, larvae, nymphs, adults). Three days after the first spray treatment, the efficacy against all mite stages (larvae, nymphs, adults) was 96.1%, and from day 7 post-treatment until the end of the trial (day 49) the efficacy exceeded 99%. In contrast, in the untreated layer house (negative control group) the mite population showed a 400% increase. No treatment-related side effects in chickens were detectable. It is concluded that two administrations of ByeMite within a 7-day interval are highly effective against D. gallinae infestations in a stocked poultry house.

  19. Field study on the efficacy of an extract of neem seed (Mite -Stop) against the red mite Dermanyssus gallinae naturally infecting poultry in Egypt.

    Science.gov (United States)

    Abdel-Ghaffar, Fathy; Sobhy, Hassan M; Al-Quraishy, Saleh; Semmler, Margit

    2008-08-01

    Infestations with the poultry red mite Dermanyssus gallinae represent a major ectoparasite problem in poultry and affects egg and meat production worldwide. The effects of the neem seed product Mite-Stop against the red poultry mite were investigated. Five primitive poultry farms in two small villages in the Nile Delta and Giza district were selected for the study. The neem extract was diluted 1:40 and 1:50 with tap water just prior to use. Application of the two dilutions of the provided product was performed to soil, cracks and crevices of the examined area as well as to mite-infested birds on day 0 and day 7. Two hours after treatment soil dust was collected from sprayed regions of the stable and from unsprayed control regions of the same stable. The treated chickens were also checked for mites 2 h after each treatment. The examination of the chickens 2 h after spraying showed that they were free of mites. The examination of treated soil with the Tullgren funnel apparatus 2 h after the first spraying on day 0 already showed a considerable reduction of living mites compared to controls. Seven days after the first treatment of the soil the number of living mites was reduced for 80% in the treated soil and decreased even more after the second spraying, since those larvae that had hatched from eggs in the meantime were killed. The 1:40 dilution of the neem seed extract with tap water was superior to the 1:50 dilution. These results clearly show a very high killing rate of the extract, if the mites come in direct contact with the compound. However, in order to obtain extinction also of hidden and freshly hatched stages repeated spraying should be done three times within 8-10 days.

  20. Highly virulent Beauveria bassiana strains against the two-spotted spider mite, Tetranychus urticae, show no pathogenicity against five phytoseiid mite species.

    Science.gov (United States)

    Wu, Shengyong; Xie, Haicui; Li, Maoye; Xu, Xuenong; Lei, Zhongren

    2016-12-01

    Entomopathogenic fungi and predatory mites can independently contribute to suppressing the two-spotted spider mite, Tetranychus urticae Koch. It is important to assess the risk of possible fungal infections in predators when a combination of them are being considered as a tandem control strategy for suppressing T. urticae. The first part of this study tested 12 Beauveria bassiana isolates for virulence in T. urticae. Strains SCWJ-2, SDDZ-9, LNSZ-26, GZGY-1-3 and WLMQ-32 were found to be the most potent, causing 37.6-49.5% adult corrected mortality at a concentration of 1 × 10(7) m/L conidia 4 days post-treatment. The second part evaluated the pathogenicity of these five strains in five species of predatory phytoseiid mites. The bioassay results indicated that all adult predatory mite mortalities ranged from 7.5 to 9.1% 4 days post-treatment. No viable fungal hyphae were found on predator cadavers. Observations with scanning electron microscopy revealed that conidia were attached to the cuticle of predatory mites within 2-12 h after spraying with strain LNSZ-26, and had germinated within 24-36 h. After 48 h, conidia had gradually been shed from the mites, after none of the conidia had penetrated the cuticular surfaces. In contrast, the germinated conidia successfully penetrated the cuticle of T. urticae, and within 60 h the fungus colonized the mite's body. Our study demonstrated that although several B. bassiana strains displayed a high virulence in T. urticae there was no evident pathogenicity to phytoseiid mites. These findings support the potential use of entomopathogenic fungus in combination with predatory mites in T. urticae control programs.