Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
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| a recessive allele (tgr-1) conditioning tomato resistance to geminivirus infection is associated with impaired viral movement. | abstract begomoviruses (the family geminiviridae) are transmitted by the whitefly bemisia tabaci and contain monopartite or bipartite circular single-stranded (ss)dna genomes. they have emerged as severe problems in the production of agricultural and horticultural crops worldwide. here, we report the identification of a tomato breeding line, fla653, that confers a high level of resistance to tomato leaf curl virus (tlcv, monopartite). genetic analysis indicated that the resistance is controlled ... | 2007 | 18943632 |
| nucleotide sequencing, whitefly transmission, and screening tomato for resistance against two newly described begomoviruses in bangladesh. | abstract the molecular diversity of tomato leaf curl viruses (tolcvs), from the two main tomato growing areas of jessore and joydebpur, bangladesh, was investigated. the viral dna was amplified from tomato plants exhibiting mild and severe symptoms by polymerase chain reaction, and the complete genomes of the tolcvs were sequenced. an isolate of the bipartite tomato leaf curl new delhi virus-severe (tolcndv-svr) was associated with the severe symptom phenotype from jessore (tolcndv-svr[jes]). a ... | 2005 | 18943559 |
| genetic and phenotypic variation of the pepper golden mosaic virus complex. | abstract three isolates of the bipartite begomovirus pepper golden mosaic virus (pepgmv) were characterized for genomic and biological properties. the complete nucleotide sequences of the dna-a and dna-b components were determined from infectious clones of pepgmv-serrano (pepgmv-ser), pepgmv-mosaic (pepgmv-mo), and pepgmv-distortion (pepgmv-d). nucleotide sequence identity among pepgmv components ranged from 91 to 96% for dna-a and from 84 to 99% for dna-b, with each pepgmv component most closel ... | 2005 | 18943475 |
| pepper (capsicum annuum) is a dead-end host for tomato yellow leaf curl virus. | abstract tomato yellow leaf curl (tylc) is one of the most devastating pathogens affecting tomato (lycopersicon esculentum) worldwide. the disease is caused by a complex of begomovirus species, two of which, tomato yellow leaf curl sardinia virus (tylcsv) and tomato yellow leaf curl virus (tylcv), are responsible for epidemics in southern spain. tylcv also has been reported to cause severe damage to common bean (phaseolus vulgaris) crops. pepper (capsicum annuum) plants collected from commercial ... | 2005 | 18943307 |
| emergence of a new cucurbit-infecting begomovirus species capable of forming viable reassortants with related viruses in the squash leaf curl virus cluster. | abstract cucurbit leaf curl virus (culcv), a whitefly-transmitted geminivirus previously partially characterized from the southwestern united states and northern mexico, was identified as a distinct bipartite begomovirus species. this virus has near sequence identity with the previously partially characterized cucurbit leaf crumple virus from california. experimental and natural host range studies indicated that culcv has a relatively broad host range within the family cucurbitaceae and also inf ... | 2002 | 18943269 |
| phenotypic expression, stability, and inheritance of a recessive resistance to monopartite begomoviruses associated with tomato yellow leaf curl disease in tomato. | tomato-infecting begomoviruses comprise a complex of monopartite and bipartite virus species that cause severe yield and quality losses worldwide. therefore, the availability of wide spectrum resistance for begomovirus control is desirable. however, limited sources of resistance are available. in this study, three tomato inbred lines with resistance to bipartite begomoviruses of brazil were tested for resistance to monopartite begomoviruses associated with the tomato yellow leaf curl disease (ty ... | 2008 | 18943231 |
| the transcript and metabolite networks affected by the two clades of arabidopsis glucosinolate biosynthesis regulators. | in this study, transcriptomics and metabolomics data were integrated in order to examine the regulation of glucosinolate (gs) biosynthesis in arabidopsis (arabidopsis thaliana) and its interface with pathways of primary metabolism. our genetic material for analyses were transgenic plants overexpressing members of two clades of genes (altered tryptophan regulation1 [atr1]-like and myb28-like) that regulate the aliphatic and indole gs biosynthetic pathways (ags and igs, respectively). we show that ... | 2008 | 18829985 |
| bioassay evaluation of the entomopathogenic fungi, beauveria bassaina vuellemin against eggs and nymphs of bemisia tabaci gennadius (homoptera: aleyrodidae). | this study was carried out to determine the lethal effect of the entomopathogenic fungi, beauveria bassaina vuell. on eggs, young and old nymphs of the whitefly, bemisia tabaci genn. mortality percentage was significantly differed based on stage of b. tabaci and conidial concentrations of b. bassina. average of the infection level to insect was very low particularly in eggs with only 4.49%, even with higher conidial concentrations (6 x 10(6) conidia ml(-1)). whereas, it was higher with 1st and 2 ... | 2008 | 18819641 |
| functional and numerical responses of eretmocerus mundus mercet (hymenoptera: aphelinidae) parasitizing cotton whitefly, bemisia tabaci gennadius (homoptera: aleyrodidae). | laboratory experiments were conducted to measure the functional and numerical responses of eretmocerus mundus mercet parasitizing cotton whitefly, bemisia tabaci gennadius. parasitoids were isolated singly for 24 h in 5 cm petri dishes with either 5, 10, 20, 40, 60 or 100 second nymphal stages of b. tabaci. results showed a typical type ii functional response, with up to 43.2 hosts attacked when 100 hosts were provided. the rate of attack and handling time were 0.0465 and 0.3341 days, respective ... | 2008 | 18810971 |
| age-specific expression of resistance to a neonicotinoid insecticide in the whitefly bemisia tabaci. | neonicotinoid insecticides retain a crucial role within many chemical and integrated control strategies for the tobacco whitefly, bemisia tabaci gennadius, in spite of the establishment of potent and widespread resistance in many areas. metabolic resistance mechanisms mediated by overexpression of p450-dependent monooxygenases have been implicated in neonicotinoid resistance in the two most prevalent b. tabaci biotypes. further characterisation of resistance to the neonicotinoid imidacloprid in ... | 2008 | 18798168 |
| toxicity of spiromesifen to the developmental stages of bemisia tabaci biotype b. | spiromesifen is a novel insecticidal/acaricidal compound derived from spirocyclic tetronic acids that acts effectively against whiteflies and mites via inhibition of acetyl-coa-carboxylase, a lipid metabolism enzyme. the effects of spiromesifen on the developmental stages of the whitefly bemisia tabaci (gennadius) were studied under laboratory conditions to generate baseline action thresholds for field evaluations of the compound. | 2009 | 18785225 |
| organophosphates' resistance in the b-biotype of bemisia tabaci (hemiptera: aleyrodidae) is associated with a point mutation in an ace1-type acetylcholinesterase and overexpression of carboxylesterase. | organophosphate (op) insecticides are inhibitors of the enzyme acetylcholinesterase (ache), which terminates nerve impulses by catalyzing the hydrolysis of the neurotransmitter acetylcholine. previous biochemical studies in bemisia tabaci (hemiptera: aleyrodidae) proposed the existence of two molecular mechanisms for ops' resistance: carboxylesterase- (coe) mediated hydrolysis or sequestration and decreased sensitivity of ache. here, two acetylcholinesterase genes, ace1 and ace2, have been fully ... | 2008 | 18721883 |
| [development and reproduction of b-biotype bemisia tabaci on four cucurbitaceous host plants]. | the study on the development and reproduction of b-biotype bemisia tabaci on four cucurbitaceous host plants, i. e., cucumber, hairy gourd, bitter cucumber, and sponge gourd, showed that the one generation development duration of b. tabaci was the shortest (19.3 d) on hairy gourd and the longest (29.0 d) on bitter cucumber, the survival rate from egg to adult was the highest (92.85%) on cucumber and the lowest (53.08%) on bitter cucumber, the laid eggs were the most (187.4 eggs per female) on cu ... | 2008 | 18655599 |
| parasitization by the wasp eretmocerus mundus induces transcription of genes related to immune response and symbiotic bacteria proliferation in the whitefly bemisia tabaci. | the whitefly bemisia tabaci (gennadius) (hemiptera: aleyrodidae), and the viruses it transmits, are a major constraint to growing vegetable crops worldwide. although the whitefly is often controlled using chemical pesticides, biological control agents constitute an important component in integrated pest management programs, especially in protected agriculture. one of these agents is the wasp eretmocerus mundus (mercet) (hymenoptera: aphelinidae). e. mundus lays its egg on the leaf underneath the ... | 2008 | 18638407 |
| inheritance of resistance to pyriproxyfen in bemisia tabaci (hemiptera: aleyrodidae) males and females (b biotype). | we evaluated effects of the insect growth regulator pyriproxyfen on bemisia tabaci (gennadius) (b biotype) (hemiptera: aleyrodidae) males and females in laboratory bioassays. insects were treated with pyriproxyfen as either eggs or nymphs. in all tests, the lc50 for a laboratory-selected resistant strain was at least 620 times greater than for an unselected susceptible strain. when insects were treated as eggs, survival did not differ between males and females of either strain. when insects were ... | 2008 | 18613596 |
| field efficacy of azadirachtin-a, tetrahydroazadirachtin-a, neemazal and endosulfan against key pests of okra (abelmoschus esculentus). | background unlike synthetic pesticides, azadirachtin-based neem pesticides are environmentally friendly and are well known for their diverse pest control properties. their use is, however, limited by the instability of azadirachtin, necessitating application at short intervals. the efficacy of relatively stable tetrahydroazadirachtin-a, therefore, needed to be established under field conditions. results: azadirachtin-a (aza-a), its stable derivative tetrahydroazadirachtin-a (tha) and other neem ... | 2008 | 18537118 |
| over-expression of cytochrome p450 cyp6cm1 is associated with high resistance to imidacloprid in the b and q biotypes of bemisia tabaci (hemiptera: aleyrodidae). | the two most damaging biotypes of bemisia tabaci, b and q, have both evolved strong resistance to the neonicotinoid insecticide imidacloprid. the major mechanism in all samples investigated so far appeared to be enhanced detoxification by cytochrome p450s monooxygenases (p450s). in this study, a polymerase chain reaction (pcr) technology using degenerate primers based on conserved p450 helix i and heme-binding regions was employed to identify p450 cdna sequences in b. tabaci that might be involv ... | 2008 | 18510975 |
| [biological aspects of bemisia tabaci (genn.) b biotype (hemiptera: aleyrodidae) on six bean genotypes]. | the silverleaf whitefly is one of the most harmful pests that attack bean crops, mainly for extracting large quantities of phloem sap and transmitting the bean golden mosaic virus. resistant germoplasm plants can be an important method for controlling this pest. the biological aspects of bemisia tabaci b biotype on bean (phaseolus vulgaris) genotypes were evaluated. the tests were conducted under laboratory conditions, with the following genotypes: arc 1, arc 3s, arc 5s, g13028, g11056 and porri ... | 2008 | 18506300 |
| [factors affecting oviposition of bemisia tabaci (genn.) biotype b in sweet pepper]. | bemisia tabaci (gen.) biotype b is considered a pest of economical importance for several vegetables. the oviposition behaviour of the whilefly was evaluated in sweet pepper plants. the trials were carried out under greenhouse condition and in the laboratory of entomology of defers/unesp, campus of ilha solteira-sp, with the sweet pepper magali-r genotype. the effect of plant age on the whitefly oviposition was evaluated in free-choice tests, in plants, 25, 30, 35, 40 and 45-day-old, as egg dist ... | 2008 | 18506298 |
| the presence of rickettsia is associated with increased susceptibility of bemisia tabaci (homoptera: aleyrodidae) to insecticides. | the presence of certain symbiotic microorganisms may be associated with insecticide resistance in insects. the authors compared the susceptibility of two isofemale lines, rickettsia-plus and rickettsia-free, of the sweet potato whitefly bemisia tabaci (gennadius) (homoptera: aleyrodidae) to major insecticides from different chemical groups, including imidacloprid, acetamiprid, thiamethoxam, pyriproxyfen, spiromesifen and diafenthiuron. | 2008 | 18432613 |
| yellow sticky trap catches of parasitoids of bemisia tabaci (hemiptera: aleyrodidae) in vegetable crops and their relationship to in-field populations. | we examined the relationship of yellow sticky trap captures of bemisia tabaci (gennadius) biotype b parasitoids to the local population of parasitoids as measured by leaf samples of parasitized whiteflies and mass release of parasitoids. traps were placed in experimental collard and cowpea field plots in charleston, sc, and in commercial organic fields of spring cantaloupe and watermelon in the imperial valley, ca. the exotic parasitoid eretmocerus emiratus zolnerowich and rose was released in i ... | 2008 | 18419911 |
| comparative transcriptome analysis of arabidopsis thaliana infested by diamond back moth (plutella xylostella) larvae reveals signatures of stress response, secondary metabolism, and signalling. | plants are exposed to attack from a large variety of herbivores. feeding insects can induce substantial changes of the host plant transcriptome. arabidopsis thaliana has been established as a relevant system for the discovery of genes associated with response to herbivory, including genes for specialized (i.e. secondary) metabolism as well as genes involved in plant-insect defence signalling. | 2008 | 18400103 |
| an approach for ipm program to control sucking pests infesting garden bean plants (phaseolus vulgaris l.) in egypt. | an approach to eatablish ipm program for some sucking pests infesting garden beans plants was carried out in two successive seasons of 2004 and 2005 under field conditions in alexandria, egypt. the sucking pests included the aphid, aphis craccivora koch (homoptera: aphididae), the white fly, bemisia tabaci genn. (homoptera: aleyroidae) and the spider mite, tetranychus urticae koch pymetrozine, thiamethoxam, carbosulfan, abamectin, azadirachtin and the detergent (masrol 410) were tested for their ... | 2007 | 18399490 |
| relationship between tomato yellow leaf curl viruses and the whitefly vector. | 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 treat ... | 2007 | 18396846 |
| three years survey of tomato yellow leaf curl sardinia virus reservoir weed hosts in southern italy. | during the period from august 2004 to june 2006 a serious tomato yellow leaf curl epidemic caused by both tomato yellow leaf curl sardinia virus (tylcsv) and tomato yellow leaf curl virus (tylcs) was observed in protected tomato crops in castrovillari, calabria region, in a group of greenhouses where tomato is grown hydroponically. a three years survey for reservoir weed hosts of these viruses was performed during summer period in order to identify where the viruses persist during the host-free ... | 2007 | 18396845 |
| molecular identification and the complete nucleotide sequence of tylcv isolate from shanghai of china. | tomato yellow leaf curl virus (tylcv) belongs to the genus begomovirus, family geminiviridae. it is transmitted by the whitefly bemisia tabaci. a pair of primers was designed according to the specific sequence of the tylcv gene and used in the pcr detection of the virus in the infected tissues of tomato grown in the shanghai area of china. dna was extracted from leaves, fruits, seeds, and roots of infected tomato plants separately. the results showed that the target fragment of about 570 bp coul ... | 2008 | 18373188 |
| [occurrence of stethorus (stethotrus) minutalus gordon & chapin (coleoptera: coccinellidae) preying bemisia tabaci biotype b (hemiptera: aleyrodidae) on cotton plant in brazil]. | this report has the objective of registering, for the first time in brazil, the predator stethorus (stethorus) minutalus gordon & chapin (scymninae, stethorini). larvae and adults were observed feeding on eggs and nymphs of the whitefly bemisia tabaci gennadius biotype b (hemiptera: aleyrodidae), on cotton plants under greenhouse condition in piracicaba, sp. probably, this coccinelid is an introduced species in the country. | 2008 | 18368255 |
| [wolbachia extensively harbored by bemisia tabaci in china]. | wolbachia are a group of maternally inherited bacteria harbored by a variety of arthropods and can manipulate the reproductivity of their hosts. eighteen populations of whiteflies were collected from hebei, xinjiang, beijing, shandong, zhejiang, guangxi, hainan, guangzhou and fujian provinces, china. these whiteflies were molecularly identified using internal transcribed spacer 1 its1 rdna sequences. they were then detected for wolbachia infection using wolbachia-specific primers designed based ... | 2008 | 18338578 |
| baseline susceptibility of bemisia tabaci b biotype (hemiptera: aleyrodidae) populations from california and arizona to spiromesifen. | susceptibility to spiromesifen, a tetronic acid derivative, was determined for three imidacloprid-resistant strains and 12 geographically discrete natural populations of bemisia tabaci (gennadius) (=bemisia argentifolii bellows & perring) (hemiptera: aleyrodidae) from california and arizona by laboratory bioassays. newly emerged first instars were sprayed with aqueous serial dilutions of spiromesifen and evaluated for toxicity to establish baseline susceptibility data. interpopulation variabilit ... | 2008 | 18330133 |
| inherited intracellular ecosystem: symbiotic bacteria share bacteriocytes in whiteflies. | symbiotic relationships with bacteria are common within the arthropoda, with interactions that substantially influence the biology of both partners. the symbionts' spatial distribution is essential for understanding key aspects of this relationship, such as bacterial transmission, phenotype, and dynamics. in this study, fluorescence in situ hybridization was used to localize five secondary symbionts from various populations and biotypes of the sweet potato whitefly bemisia tabaci: hamiltonella, ... | 2008 | 18285399 |
| biotype status and distribution of bemisia tabaci (hemiptera: aleyrodidae) in shandong province of china based on mitochondrial dna markers. | bemisia tabaci has caused significant crop losses in china during the last decade. recent research has shown that two potentially invasive variants, biotypes b and q, have been found in several regions of china. our objective was to determine the biotype status and the distribution of b. tabaci in shandong province, an important agricultural region of china. based on mitochondrial dna markers, both biotypes b and q were detected, with b being the predominant biotype. the results indicate that th ... | 2007 | 18284755 |
| microsatellite variability in the entomopathogenic fungus paecilomyces fumosoroseus: genetic diversity and population structure. | the hyphomycete paecilomyces fumosoroseus (pfr) is a geographically widespread fungus capable of infecting various insect hosts. the fungus has been used for the biological control of several important insect pests of agriculture. however knowledge of the fungus' genetic diversity and population structure is required for its sustainable use as a biological control agent. we investigated length and sequence polymorphisms of nine microsatellite loci for 33 pfr accessions sampled from various host ... | 2008 | 18268903 |
| genetic structure of the invasive pest bemisia tabaci: evidence of limited but persistent genetic differentiation in glasshouse populations. | the geographic range of plant pests can be modified by the use of glasshouses. bemisia tabaci, originating from warm to hot climates, has been shown to be a complex of distinct genetic groups with very limited gene flow. the genetic structure of this pest was studied in glasshouses in southern france, a region beyond the northern limit of its open-field development area in europe. seven microsatellite loci were scored in 22 populations sampled from various regions over 3 years. two genetic group ... | 2008 | 18073781 |
| asymmetric mating interactions drive widespread invasion and displacement in a whitefly. | the role of behavioral mechanisms in animal invasions is poorly understood. we show that asymmetric mating interactions between closely related but previously allopatric genetic groups of the whitefly bemisia tabaci, a haplodiploid species, have been a driving force contributing to widespread invasion and displacement by alien populations. we conducted long-term field surveys, caged population experiments, and detailed behavioral observations in zhejiang, china, and queensland, australia, to inv ... | 2007 | 17991828 |
| real-time pcr for the quantitation of tomato yellow leaf curl sardinia virus in tomato plants and in bemisia tabaci. | tomato yellow leaf curl sardinia virus (tylcsv) (geminiviridae) is an important pathogen severely affecting tomato production in the mediterranean basin. although diagnostic protocols are available for its detection in plants and its vector bemisia tabaci (gennadius), suitable tools for estimating and comparing viral loads in plant and insect tissues are needed. in this paper, real-time pcr methods are described for quantitation of tylcsv in both tomato plant and whitefly extracts. the dna extra ... | 2008 | 17980920 |
| expression of stress-response proteins upon whitefly-mediated inoculation of tomato yellow leaf curl virus in susceptible and resistant tomato plants. | to better understand the nature of resistance of tomato to the whitefly (bemisia tabaci, b biotype)-transmitted tomato yellow leaf curl virus (tylcv), whiteflies and tylcv were considered as particular cases of biotic stresses and virus resistance as a particular case of successful response to these stresses. two inbred tomato lines issued from the same breeding program that used solanum habrochaites as a tylcv resistance source, one susceptible and the other resistant, were used to compare the ... | 2007 | 17977149 |
| field evaluation of resistance to pyriproxyfen in bemisia tabaci (b biotype). | we determined effects of aerial sprays of the insect growth regulator pyriproxyfen on sweetpotato whitefly, bemisia tabaci (gennadius) (b biotype), in arizona cotton (gossypium spp.) fields. we measured survival for males and females from a susceptible strain and a laboratory-selected resistant strain, as well as for hybrid female progeny from crosses between the strains. insects were exposed directly to pyriproxyfen sprays in the field or indirectly in the laboratory by rearing them on sprayed ... | 2007 | 17972644 |
| high-throughput allelic discrimination of b and q biotypes of the whitefly, bemisia tabaci, using taqman allele-selective pcr. | b and q biotypes of the whitefly, bemisia tabaci (gennadius), are generally regarded as the most significant given their global distribution and strong resistance to insecticides. since these biotypes can coexist and differ markedly in their insecticide resistance profiles, a rapid but reliable means of discriminating between them would be a valuable complement to resistance monitoring and management programmes. recently, pcr-based methods have been developed to determine the biotype status of b ... | 2008 | 17972303 |
| a divergent isolate of tomato yellow leaf curl virus from oman with an associated dna beta satellite: an evolutionary link between asian and the middle eastern virus-satellite complexes. | tomato is cultivated in the coastal region of al-batinah, in the sultanate of oman, during the winter season, to meet the high demand for fresh produce in the domestic market. in order to identify the causal agent of a widespread disease associated with infestations of the whitefly bemisia tabaci (genn.) leaves were collected from tomato plants showing symptoms characteristic of the disease in al-batinah during 2004 and 2005. total nucleic acids were isolated from the tomato leaves and used as t ... | 2008 | 17932737 |
| temporal synergism can enhance carbamate and neonicotinoid insecticidal activity against resistant crop pests. | piperonyl butoxide (pbo) effectively synergises synthetic pyrethroids, rendering even very resistant insect pests susceptible, provided a temporal element is included between exposure to synergist and insecticide. this concept is now applied to carbamates and neonicotinoids. | 2008 | 17926308 |
| development of silverleaf assay, protein and nucleic acid-based diagnostic techniques for the quick and reliable detection and monitoring of biotype b of the whitefly, bemisia tabaci (gennadius). | the aim of this study was to develop and optimize silverleaf bioassay, esterase analysis and pcr-based techniques to distinguish quickly and reliably biotype b of the whitefly, bemisia tabaci (gennadius), from indian indigenous biotypes. zucchini and squash readily develop silverleaf symptoms upon feeding by the b biotype, but they are not readily available in indian markets. a local pumpkin variety 'big' was, therefore, used in silverleaf assay, which developed symptoms similar to those on zucc ... | 2007 | 17916268 |
| [insecticide resistance of bemisia tabaci field populations]. | resistance to 13 insecticides in field populations of bemisia tabaci from six regions (fuzhou, zhangzhou, longyan, sanming, nanping, ningde) of fujian province, china was monitored by adult leaf-dipping bioassay. compared with the susceptible sud-s strain, all the six field populations exhibited high levels of resistance to lambda-cyhalothrin (838.38-2460.52 fold), fenpropathrin (244.64-834.29 fold), cypermethrin (116.02-266.35 fold), deltamethrin (81.75-124.18 fold), acephate (425.18-875.56 fol ... | 2007 | 17886654 |
| plant-mediated interactions between whiteflies, herbivores, and natural enemies. | whiteflies (homoptera: aleyrodidae) comprise tiny phloem-sucking insects. the sessile development of their immatures and their phloem-feeding habits (with minimal physical plant damage) often lead to plant-mediated interactions with other organisms. the main data come from the polyphagous pest species bemisia tabaci (gennadius) and trialeurodes vaporariorum (westwood), which are intricately associated with their host plants. although these associations might not represent aleyrodids in general, ... | 2008 | 17877454 |
| effects of proportion and configuration of bacillus thuringiensis cotton on pest abundance, damage, and yield. | bacillus thuringiensis (bt) transgenic cotton, gossypium hirsutum l., kills several economically important pests, reducing injury and increasing yields. refuges of non-bt cotton are currently planted with bt cotton in different designs to slow pest resistance evolution. to compare the effects of differences in bt/non-bt plant heterogeneity found in different refuge designs on square (flower bud) damage, abscissions, sap-feeding herbivore densities, and yield in cotton, four types of 24-row cotto ... | 2007 | 17849898 |
| within-plant distribution of bemisia tabaci (homoptera: aleyrodidae) adults and immatures on greenhouse-grown winter cucumber plants. | within-plant distribution of adults, pupae, nymphs, and eggs of bemisia tabaci (gennadius) (homoptera: aleyrodidae) on leaves of greenhouse-grown winter cucumber, cucumis sativum l., plants were studied in field plots for integrated pest management decision making. distribution of specific life stages depended on the leaf positions. the leaves with most abundance and low or lowest variation of whiteflies were leaves 8-12 for adults, 8-11 for pupae, 6-12 for nymphs, and 6-9 for eggs. in light of ... | 2007 | 17849865 |
| toxicity of seven foliar insecticides to four insect parasitoids attacking citrus and cotton pests. | laboratory studies were carried out to compare the toxicity of seven foliar insecticides to four species of adult beneficial insects representing two families of hymenoptera: aphelinidae (aphytis melinus debach, eretmocerus eremicus rose & zolnerowich, and encarsiaformosa gahan) and mymaridae (gonatocerus ashmeadi girault) that attack california red scale, aonidiella aurantii (maskell); sweetpotato whitefly, bemisia tabaci (gennadius) (both e. eremicus and e. formosa); and glassy-winged sharpsho ... | 2007 | 17849851 |
| evidence from molecular markers and population genetic analyses suggests recent invasions of the western north pacific region by biotypes b and q of bemisia tabaci (gennadius). | invasive events by bemisia tabaci (gennadius) biotypes in various parts of the world are of continuing interest. the most famous is biotype b that has caused great economic losses globally. in addition, biotype q has also recently been reported to be a new invasive pest. these two biotypes have been monitored for some time in the western north pacific region, but the invasive events and population genetic structures of these two biotypes are still not clear in this region. in this study, the mit ... | 2007 | 17716487 |
| assessment of herbivore performance on host plants. | two models for assessing the performance of herbivores on a variety of host plants are developed by combining knowledge of population genetics and population ecology, especially that of the fixation probability of mutant genes. the absolute host performance model precisely assesses host performance for one herbivore population based on parameters of fecundity, larval survivorship, and selection pressure. the relative host performance model compares host performance for one population among diffe ... | 2007 | 17716460 |
| [biology and non-preference for oviposition by bemisia tabaci (gennadius) biotype b (hemiptera: aleyrodidae) on cotton cultivars]. | the purposes of this work were to evaluate some biological aspects of bemisia tabaci (gennadius) biotype b at egg and nymphal stages and to evaluate the non-preference for oviposition and its correlation with the number and type of trichomes on the cotton cultivars brs ipê, brs 186-precoce 3, brs acala, brs verde, brs-200 marrom, brs cedro, brs ita 90-2 and brs aroeira. the experiments were conducted in climatic chambers at 28 +/- 2 degrees c, 70% rh and photophase of 14h, and in greenhouse. egg ... | 2007 | 17710328 |
| introgression of resistance genes between populations: a model study of insecticide resistance in bemisia tabaci. | introgression is a key process in conservation biology, genetic modification of (crop) species and in the evolutionary ecology of many species. here we consider the case of introgression of insecticide resistance in the whitefly, bemisia tabaci. b. tabaci is a species complex consisting of a range of biotypes, known to have a high degree of inter-biotype reproductive isolation. in areas where insecticide resistant and susceptible biotypes of b. tabaci coexist, introgression of the resistance gen ... | 2007 | 17658572 |
| adult bemisia tabaci biotype b can induce silverleafing in squash. | bemisia tabaci biotype b is one of three genetic groups able to induce silverleafing in squash. several earlier studies had observed that this physiological change was induced only through the feeding of juvenile whiteflies. this study uses adult males only to show that after 11 days the adult males were able to begin to induce silverleafing. further, the response was density-dependent with 120 adults inducing the first signs of silverleafing in 11 days, 90 adults in 13 days and 60 adults in 15 ... | 2007 | 17645825 |
| biotype-dependent secondary symbiont communities in sympatric populations of bemisia tabaci. | the sweet potato whitefly, bemisia tabaci, harbors portiera aleyrodidarum, an obligatory symbiotic bacterium, as well as several secondary symbionts including rickettsia, hamiltonella, wolbachia, arsenophonus, cardinium and fritschea, the function of which is unknown. bemisia tabaci is a species complex composed of numerous biotypes, which may differ from each other both genetically and biologically. only the b and q biotypes have been reported from israel. secondary symbiont infection frequenci ... | 2007 | 17645822 |
| global relationships of bemisia tabaci (hemiptera: aleyrodidae) revealed using bayesian analysis of mitochondrial coi dna sequences. | bemisia tabaci (gennadius) (hemiptera: aleyrodidae) is a species complex that is one of the most devastating agricultural pests worldwide and affects a broad range of food, fiber and ornamental crops. unfortunately, using parsimony and neighbor joining methods, global phylogenetic relationships of the major races/biotypes of b. tabaci remain unresolved. aside from the limitations of these methods, phylogenetic analyses have been limited to only small subsets of the global collection of b. tabaci ... | 2007 | 17627853 |
| development of real-time rt-pcr assays for the detection of cucumber vein yellowing virus (cvyv) and cucurbit yellow stunting disorder virus (cysdv) in the whitefly vector bemisia tabaci. | reverse transcription followed by real-time pcr assays based on taqman chemistry have been developed for the detection and quantification of cucumber vein yellowing virus (cvyv) and cucurbit yellow stunting disorder virus (cysdv) in individual adults of the whitefly vector bemisia tabaci. the method includes an internal control for the detection of a gene from b. tabaci to compensate for variations in extraction efficiency. the assays designed were used to estimate proportions of viruliferous wh ... | 2007 | 17624449 |
| potentiation/antagonism of pyrethroids with organophosphate insecticides in bemisia tabaci (homoptera: aleyrodidae). | the binary mixtures of pyrethroids cypermethrin, alpha-cypermethrin, zeta-cypermethrin, bifenthrin, fenpropathrin, lambda-cyhalothrin, and deltamethrin plus organophosphates ethion, profenofos, chlorpyrifos, quinalphos, acephate, methamidophos, methyl parathion, and triazophos were evaluated on putatively resistant field populations of bemisia tabaci (gennadius) (homoptera: aleyrodidae) from pakistan using a leaf-dip bioassay. ethion exhibited good potentiation with all the pyrethroids. quinalph ... | 2007 | 17598552 |
| field evaluation of different insecticide use strategies as resistance management and control tactics for bemisia tabaci (hemiptera: aleyrodidae). | various insecticide use strategies including rotations, sequential use, and mixtures were evaluated experimentally on bemisia tabaci (gennadius) in california and arizona (u.s.a.) cotton fields. toxicological responses of adult b. tabaci were measured along with preimaginal densities and cotton yields from plots subjected to different insecticide regimens. weekly monitoring for susceptibility changes over ten consecutive weeks in four different trials failed to detect significant differences bet ... | 2002 | 17598296 |
| reversal of resistance to pyriproxyfen in the q biotype of bemisia tabaci (hemiptera: aleyrodidae). | pyriproxyfen, a juvenile hormone (jh) mimic, is a biorational insecticide that disrupts insect development. it is one of the principal insecticides being used to control bemisia tabaci (gennadius) on cotton, and has many environmentally positive attributes that make it compatible with integrated pest management (ipm) programs. in israel, a high level of resistance to pyriproxyfen has been observed in several isolated regions. here, tests were conducted to establish whether temporal refuges from ... | 2007 | 17582630 |
| gene expression in pyriproxyfen-resistant bemisia tabaci q biotype. | pyriproxyfen is a biorational insecticide that acts as a juvenile hormone (jh) analogue and disrupts insect development with an unknown molecular mode of action. pyriproxyfen is one of the major insecticides used to control the whitefly bemisia tabaci (gennadius) and comply with integrated pest management (ipm) programmes, resulting in minimal effects on the environment, humans and beneficial organisms. during the last few years, resistance to pyriproxyfen has been observed in several locations ... | 2007 | 17569108 |
| rnai-mediated resistance to bean golden mosaic virus in genetically engineered common bean (phaseolus vulgaris). | bean golden mosaic virus (bgmv) is transmitted by the whitefly bemisia tabaci in a persistent, circulative manner, causing the golden mosaic of common bean (phaseolus vulgaris l.). the characteristic symptoms are yellow-green mosaic of leaves, stunted growth, or distorted pods. the disease is the largest constraint to bean production in latin america and causes severe yield losses (40 to 100%). here, we explored the concept of using an rna interference construct to silence the sequence region of ... | 2007 | 17555279 |
| tissue-specific gene silencing by rna interference in the whitefly bemisia tabaci (gennadius). | the hemipteran whitefly bemisia tabaci (gennadius) species complex and the plant viruses they transmit pose major constraints to vegetable and fiber production, worldwide. the whitefly tissue- and developmental-specific gene expression has not been exhaustively studied despite its economic importance. in 2002, a functional genomic project was initiated, which generated several thousands expressed sequence tags (ests) and their sequence. this project provides the basic information to design exper ... | 2007 | 17550829 |
| toxicity of insecticides to the sweetpotato whitefly (hemiptera: aleyrodidae) and its natural enemies. | efficient chemical control is achieved when insecticides are active against insect pests and safe to natural enemies. in this study, the toxicity of 17 insecticides to the sweetpotato whitefly, bemisia tabaci (gennadius), and the selectivity of seven insecticides to natural enemies of this insect pest were evaluated. to determine the insecticide toxicity, b. tabaci adults were exposed to abamectin, acephate, acetamiprid, cartap, imidacloprid, malathion, methamidophos, bifenthrin, cypermethrin, d ... | 2007 | 17523144 |
| ligand binding by recombinant domains from insect ecdysone receptors. | the ligand binding domains (lbds) from the ecr and usp proteins of four insect pests (lucilia cuprina, myzus persicae, bemisia tabaci, helicoverpa armigera) were purified as recombinant heterodimers. the k(d) values for [(3)h]-ponasterone a binding by lbd heterodimers that included the hinge regions (i.e., de/f heterodimers) ranged 0.7-2.5 nm, with k(i) values for ecdysteroid and dibenzoylhydrazine ligands ranging from 0.1 nm to >448 microm. the k(d) and k(i) values for a recombinant h. armigera ... | 2007 | 17517338 |
| prevalence of wolbachia infection in bemisia tabaci. | wolbachia are obligate intracellular bacteria present in reproductive tissues of many arthropod species. it has been reported that few silverleafing populations of bemisia tabaci were positive for wolbachia, whereas non-silverleafing populations were more likely infected with wolbachia and all that infect b. tabaci are wolbachia belonging to supergroup b. however, current detection methods were shown to be not sensitive enough to uncover all infections. herein, a protocol based on polymerase cha ... | 2007 | 17487529 |
| a multiplex pcr method discriminating between the tylcv and tylcv-mld clades of tomato yellow leaf curl virus. | tomato yellow leaf curl virus (tylcv) is one of the causal agents of tomato yellow leaf curl disease (tylcd) and can cause up to 100% yield losses in tomato fields. as tylcv continues to spread, many isolates have been described in different parts of the world. recently two closely related but distinct tylcv clades, called tylcv and tylcv-mld, have been identified. isolates from those two clades differ mainly in the nucleotide sequences of their replication associated protein genes but do not di ... | 2007 | 17485124 |
| pest-managing activities of plant extracts and anthraquinones from cassia nigricans from burkina faso. | insecticidal activity of eight plants collected from burkina faso was studied using mosquito (ochlerotatus triseriatus), helicoverpa zea and heliothis virescens larvae and adult white fly (bemisia tabaci). the n-hexane, ethyl acetate and methanol extracts of pseudocedrela kotschyi, strophantus hispidus, securidaca longepedunculata, sapium grahamii, swartzia madagascariensis, cassia nigricans, jatropha curcas and datura innoxia were used in this study. extracts were tested at 250 microg/ml concen ... | 2008 | 17478091 |
| effects of azadirachtin, abamectin, and spinosad on sweetpotato whitefly (homoptera: aleyrodidae) on tomato plants under laboratory and greenhouse conditions in the humid tropics. | direct and residual toxicity of neemazal-t/s (azadirachtin), success (spinosad), and abamectin was tested against different life stages of sweetpotato whitefly, bemisia tabaci (gennadius) (homoptera: aleyrodidae), under air-conditioned laboratory conditions and in a tropical net greenhouse. neemazal-t/s and abamectin deterred the settling of adults on tomato, lycopersicon esculentum mill (solanaceae), plants and consequently reduced egg deposition. no such effect was detected for success. all th ... | 2007 | 17461066 |
| [flight behaviors of bemisia tabaci and corresponding ipm strategies]. | bemisia tabaci, a pest insect with stronger capabilities of flying and host plant-exploitation, is capable of flying 150 m high and over a distance as far as 7 km, but hardly flies higher than 0. 5 m and long distance in food-abundant areas. b. tabaci has the characteristics of both searching-and migrating flying, which enable it to exploit and locate on suitable hosts. up to now, no oogenesis-flight syndrome of b. tabaci has been detected. visual spectrum, air temperature and relative humidity, ... | 2007 | 17450755 |
| mitochondrial dna variability and development of a pcr diagnostic test for populations of the whitefly bemisia afer (priesner and hosny). | the whitefly, bemisia afer (hemiptera; aleyrodidae), is emerging as a major agricultural pest. the current identification methods based on adult and pupal morphology are laborious and unreliable. a diagnostic polymerase chain reaction (pcr) protocol was developed for the first time in this study to discriminate b. afer from other whitefly species. primers specific to mitochondrial cytochrome oxidase i gene (mtcoi) were designed to amplify a band of approx 650 bp. the pcr products were sequenced ... | 2007 | 17401147 |
| integrated management of tylcv/tylcsv on greenhouse hydroponic tomatoes in southern italy. | tomato yellow leaf curl (tylc) caused by tomato yellow leaf curl virus (tylcv) and tomato yellow leaf curl sardinia virus (tylcsv), vectored by the whitefly bemisia tabaci, is a major disease of tomato in sardinia and sicily, and is becoming a serious threat in southern italy too. tylcsv was first reported in calabria region in 1991, but apparently it was an occasional outbreak, and b. tabaci was not detected. later, during the 2003-2004 winter, a serious epidemic was observed in protected tomat ... | 2006 | 17390886 |
| typing of tomato yellow leaf curl viruses and their vector in italy. | a molecular survey of tylcv/tylcsv and their associated vector bemisia tabaci, was performed during 2004-2005 in five regions of southern italy: i.e. sardinia (one locations), sicily (one location), calabria (three locations), campania (two locations) and basilicata (one location). a total of 71 tomato samples were checked for virus infection and for the presence of the vector. degenerate primers allowing the amplification of the coat protein gene of both tylcsv and tylcv isolates were designed. ... | 2006 | 17390884 |
| comparative study of the five biological parameters of cotton whitefly bemisia tabaci and silverleaf whitefly b. argentifolii bellows and perring reared on cotton under laboratory condition. | the five biological parameters of sweetpotato whitefly, bemisia tabaci (genn.) and silverleaf whitefly bemisia argentifolii bellows and perring (hom: aleyrodidae) as an important pest of cotton were compared on cotton in laboratory condition. the infested leaves containing nymphs and pupae were collected from cotton fields in iran. experiments were conducted in a growth chamber under 24+/-2 degrees c, 55+/-3% rh and 16:8 (l:d) photoperiod on cotton, gossypium hirsutum l. the newly emerged popula ... | 2006 | 17385531 |
| detection by rapd-pcr of polymorphism in populations of bemisia tabaci (genn.) collected on four host plants from iran. | the sweetpotato whitefly, bernisia tabaci (genn.) (hom: aleyrodidae) is a major pest of field crops, vegetables and ornamentals in iran. in this study, the infested leaves of cucumber (cucurnis sativus l.) zucchini (cucurbita pepo l.) eggplant (solanum melongena l.) and cotton (gossypium hirsutum l.) with whitefly nymphs and pupae were collected from iran, and were transferred to the laboratory. the newly emerged males and females of each population were released separately into a large cage set ... | 2006 | 17385530 |
| pathogenicity of fusarium semitectum against crop pests and its biosafety to non-target organisms. | microbial control is receiving more attention, since these alternative tactics, compared to chemical control methods, are energy saving, non polluting, ecologically sound and sustainable. a mycopathogen, fusarium semitectum berk. and rav. (arsef 7233) was isolated from diseased cadavers of aphid (aphis gossypii) and cultured in saboraud maltose agar supplemented with yeast extract medium (smay). being isolated first time from the chilli ecosystem its potential was evaluated. experiments were con ... | 2006 | 17385514 |
| effect of zohar lq-215, a biorational surfactant, on the sweetpotato whitefly bemisia tabaci (biotype b). | zohar lq-215, a surfactant based on plant oils, able to control nymphs of the whitefly, bemisia tabaci (gennadius), under laboratory and field conditions. to evaluate the effects of the surfactant on the nymph stages of whitefly under laboratory conditions, potted cotton seedlings infested with 1st- or 3rd-instars were treated with the compound aqueous solutions. lc90 values of zohar lq-215 on 1st and 3rd-nymphs, based on mortality curves, were 0.78% and 1.14%, respectively. adult mortality of 1 ... | 2006 | 17385496 |
| the mi-1-mediated pest resistance requires hsp90 and sgt1. | the tomato (solanum lycopersicum) mi-1 gene encodes a protein with putative coiled-coil nucleotide-binding site and leucine-rich repeat motifs. mi-1 confers resistance to root-knot nematodes (meloidogyne spp.), potato aphids (macrosiphum euphorbiae), and sweet potato whitefly (bemisia tabaci). to identify genes required in the mi-1-mediated resistance to nematodes and aphids, we used tobacco rattle virus (trv)-based virus-induced gene silencing (vigs) to repress candidate genes and assay for nem ... | 2007 | 17351050 |
| 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. | 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 th ... | 2007 | 17334947 |
| effects of host plants on insecticide susceptibility and carboxylesterase activity in bemisia tabaci biotype b and greenhouse whitefly, trialeurodes vaporariorum. | bemisia tabaci (gennadius) biotype b and the greenhouse whitefly, trialeurodes vaporariorum (westwood), have become serious pests of cotton and vegetable crops in china since the early 1990s. in recent years, however, b. tabaci have broken out more frequently and widely than have t. vaporariorum. the b. tabaci biotype b has also developed higher resistance to several insecticides. here, the effects of four different host plants on the insecticide susceptibility of b. tabaci biotype b and t. vapo ... | 2007 | 17323411 |
| toxicity and feeding deterrence of crude toxin extracts of lecanicillium (verticillium) lecanii (hyphomycetes) against sweet potato whitefly, bemisia tabaci (homoptera: aleyrodidae). | crude toxins [toxin(v3450) and toxin(vp28,) extracted from lecanicillium (verticillium) lecanii (zimmermann) gams & zare strain v3450 and vp28 respectively] were tested for contact toxicity, feeding deterrence and repellent activity against the sweet potato whitefly, bemisia tabaci (gennadius) (homoptera: aleyrodidae). both toxins showed ovicidal activity to eggs, with lc(50) values of 447 and 629 mg l(-1) respectively. nymphs of b. tabaci were the most susceptible stages (lc(50) values were cal ... | 2007 | 17315271 |
| temporal synergism by microencapsulation of piperonyl butoxide and alpha-cypermethrin overcomes insecticide resistance in crop pests. | a microencapsulated formulation that gives a burst release of piperonyl butoxide (pbo) several hours before a burst release of a conventional pyrethroid can effectively overcome metabolic resistance in bemisia tabaci gennadius, helicoverpa armigera (hübner), aphis gossypii glover and myzus persicae sulzer. this increase in efficacy against resistant pests was reflected in a field trial against b. tabaci on cotton, eliminating the need for two treatments. the ratio between the active insecticide ... | 2007 | 17304634 |
| biotype status and genetic polymorphism of the whitefly bemisia tabaci (hemiptera: aleyrodidae) in greece: mitochondrial dna and microsatellites. | the genetic polymorphism and the biotype identity of the tobacco whitefly bemisia tabaci (gennadius) have been studied in population samples taken from different localities within greece from cultivated plants growing in greenhouses or in open environments and from non-cultivated plants. two different approaches were used: sequencing of the mitochondrial cytochrome oxidase i (mtcoi) gene and genotyping using microsatellite markers. analyses of the mtcoi sequences revealed a high homogeneity betw ... | 2007 | 17298679 |
| efficacy of the entomopathogenic nematode, steinernema feltiae, against sweetpotato whitefly bemisia tabaci (homoptera: aleyrodidae) under laboratory and glasshouse conditions. | the potential of using the entomopathogenic nematode steinernema feltiae to control the sweetpotato whitefly bemisia tabaci (gennadius) has been established in previous laboratory studies. however, laboratory studies can overestimate the level of control achieved by biocontrol agents in the glasshouse. glasshouse trials are therefore required to confirm laboratory results before full-scale commercial development is considered. under both controlled laboratory and glasshouse conditions high morta ... | 2007 | 17298677 |
| purification and characterization of recombinant ligand-binding domains from the ecdysone receptors of four pest insects. | cloned ecr and usp cdnas encoding the ecdysone receptors of four insect pests (lucilia cuprina, myzus persicae, bemisia tabaci, helicoverpa armigera) were manipulated to allow the co-expression of their ligand binding domains (lbds) in insect cells using a baculovirus vector. recombinant de/f segment pairs (and additionally, for h. armigera, an e/f segment pair) from the ecr and usp proteins associated spontaneously with high affinity to form heterodimers that avidly bound an ecdysteroid ligand. ... | 2007 | 17275327 |
| vector-virus mutualism accelerates population increase of an invasive whitefly. | the relationships between plant viruses, their herbivore vectors and host plants can be beneficial, neutral, or antagonistic, depending on the species involved. this variation in relationships may affect the process of biological invasion and the displacement of indigenous species by invaders when the invasive and indigenous organisms occur with niche overlap but differ in the interactions. the notorious invasive b biotype of the whitefly complex bemisia tabaci entered china in the late 1990s an ... | 2007 | 17264884 |
| ecdysteroids and juvenile hormones of whiteflies, important insect vectors for plant viruses. | ecdysteroids and juvenile hormones (jhs) regulate many physiological events throughout the insect life cycle, including molting, metamorphosis, ecdysis, diapause, reproduction, and behavior. fluctuation of whitefly ecdysteroid levels and the identity of the whitefly molting hormone (20-hydroxyecdysone) have only been reported within the last few years. an ecdysteroid commitment peak that is associated with the reprogramming of tissues for a metamorphic molt in many holometabolous and some hemime ... | 2007 | 17258230 |
| tropical whitefly ipm project. | the tropical whitefly ipm project (twfp) is an initiative of the systemwide ipm programme of the consultative group on international agricultural research (cgiar), financed by the department for international development (dfid) of the united kingdom, the danish international development agency (danida), the united states department of agriculture (usda) and agency for international development (usaid), the australian centre for international agricultural research (aciar), and the new zealand age ... | 2007 | 17222696 |
| [predation of axinoscymnus cardilobus to bemisia tabaci]. | the laboratory study on the predation of axinoscymnus cardilobus to bemisia tabaci showed that the functional response of a. cardilobus to b. tabaci was of holling' s type ii. with the increasing age of b. tabaci, the searching rate of a. cardilobus adult decreased, and its handling time became longer. the searching rate of a. cardilobus larva was increased with its age, and the handling time became shorter. the mutual interference in individual predator could be described by hassell and varley ... | 2006 | 17209395 |
| buprofezin inhibits acetylcholinesterase activity in b-biotype bemisia tabaci. | b-biotype bemisia tabaci is a severe insect pest worldwide in many ornamental, agricultural, and horticultural industries. control of this insect is hampered by resistance to many acetylcholinesterase (ache)-inhibiting insecticides, such as organophosphates and carbamates. consequently, insect growth regulators such as buprofezin, which act by inhibiting chitin synthesis, are being investigated for use against b-biotype b. tabaci in australia. this study discusses the effects of buprofezin on b. ... | 2006 | 17192620 |
| silverleaf whitefly induces salicylic acid defenses and suppresses effectual jasmonic acid defenses. | the basal defenses important in curtailing the development of the phloem-feeding silverleaf whitefly (bemisia tabaci type b; slwf) on arabidopsis (arabidopsis thaliana) were investigated. sentinel defense gene rnas were monitored in slwf-infested and control plants. salicylic acid (sa)-responsive gene transcripts accumulated locally (pr1, bgl2, pr5, sid2, eds5, pad4) and systemically (pr1, bgl2, pr5) during slwf nymph feeding. in contrast, jasmonic acid (ja)- and ethylene-dependent rnas (pdf1.2, ... | 2007 | 17189328 |
| arabidopsis transcriptome changes in response to phloem-feeding silverleaf whitefly nymphs. similarities and distinctions in responses to aphids. | phloem-feeding pests cause extensive crop damage throughout the world, yet little is understood about how plants perceive and defend themselves from these threats. the silverleaf whitefly (slwf; bemisia tabaci type b) is a good model for studying phloem-feeding insect-plant interactions, as slwf nymphs cause little wounding and have a long, continuous interaction with the plant. using the affymetrix ath1 genechip to monitor the arabidopsis (arabidopsis thaliana) transcriptome, 700 transcripts we ... | 2007 | 17189325 |
| sublethal effects of beauveria bassiana (balsamo) vuillemin (deuteromycotina: hyphomycetes) on the whitefly bemisia tabaci (gennadius) (hemiptera: aleyrodidae) under laboratory conditions. | sublethal effects were evaluated in subsequent generations of whiteflies bemisia tabaci (gennadius) arising from parental generations exposed in the four nymphal stages to the fungus beauveria bassiana (balsamo) vuillemin. examples of such effects include impaired fertility, production of malformations or external variations, and reduced survival of later generations. malformations of the head, legs, wings or abdomen were not observed in adults derived from treated nymphs, nor were negative effe ... | 2006 | 17146585 |
| host-parasitoid interactions relating to penetration of the whitefly, bemisia tabaci, by the parasitoid wasp, eretmocerus mundus. | it has been reported that the aphelinid wasp eertmocerus mundus parasitizes all four nymphal instars of the sweet potato whitefly, bemisia tabaci (biotype b), with 3rd instars being the preferred hosts. the parasitoid lays its egg on the leaf underneath the host nymph. first instars hatch and later penetrate the whitefly. previous studies have shown that the initiation of parasitoid penetration induces the host to form a cellular capsule around the parasitoid. as described here, females never ov ... | 2005 | 17119628 |
| the broadly insecticidal photorhabdus luminescens toxin complex a (tca): activity against the colorado potato beetle, leptinotarsa decemlineata, and sweet potato whitefly, bemisia tabaci. | toxin complex a (tca), a high molecular weight insecticidal protein complex produced by the entomopathogenic bacterium photorhabdus luminescens, has been found to be orally toxic to both the colorado potato beetle, leptinotarsa decemlineata, and the sweet potato whitefly, bemisia tabaci biotype b. the 48 hour lc50 for tca against neonate l. decemlineata was found to be 2.7 ppm, and the growth of 2nd instar l. decemlineata exposed to tca for 72 hours was almost entirely inhibited at concentration ... | 2005 | 17119614 |
| effect of cotton cultivar on performance of aphis gossypii (homoptera: aphididae) in iran. | cotton aphids, aphis gossypii glover (homoptera: aphididae), obtained from cotton, gossypium hirsutum l., fields in the gorgan region of northern iran, were colonized on 'varamin' cotton plants in a growth chamber. the development, survivorship, and life table parameters of the cotton aphid were evaluated at 27.5 +/- 1 degrees c, 65 +/- 10% rh, and aphotoperiod of 14:10 (l:d) h of artificial light on five commonly growing cotton cultivars: varamin, 'sealand' (relatively resistant cultivar), 'bak ... | 2006 | 17066818 |
| [spatial patterns of bemisia tabaci (gennadius) population in cotton fields]. | field investigations on the vertical and horizontal distribution patterns of bemisia tabaci (gennadius) population on bt cotton guokang no. 22 and non-bt cotton simian no. 3 showed that in july, no obvious difference was found in the vertical distribution of b. tabaci population on cotton plant, but in august, the population density was significantly higher on the upper part of cotton plant than on its middle and lower parts. the horizontal distribution patterns of b. tabaci adult and nymph were ... | 2006 | 17044499 |
| bemnisia tabaci feeding induces pathogenesis-related proteins in cassava (manihot esculenta crantz). | cassava (manihot esculenta cranzts) plants fed upon by whitefly bemisia tabaci showed increased levels of pathogenesis-related (pr) proteins, such as beta-1, 3-glucanase, peroxidase and chitinase activities, as compared to uninfested plants. the enzymes increased in specific activities from 2 to 7 fold and protein content in leaf extracts decreased in whitefly-infested plants, compared to uninfested plants. among the three pr proteins, b. tabaci feeding induced significantly higher beta-1, 3-glu ... | 2006 | 16967908 |
| modeling evolution of resistance to pyriproxyfen by the sweetpotato whitefly (homoptera: aleyrodidae). | we used computer simulations to examine evolution of resistance to the insect growth regulator (igr) pyriproxyfen by the sweetpotato whitefly, bemisia tabaci (gennadius), biotype b [=bemisia argentifolii (bellows & perring)]. consistent with trends seen in cotton (gossipyium spp.) fields in arizona and israel, results suggest that evolution of resistance to pyriproxyfen may occur rapidly in this haplodiploid insect. similar to results from models of diploid insects, resistance evolved faster wit ... | 2006 | 16937698 |
| feeding preference of macrolophus caliginosus (heteroptera: miridae) on bemisia tabaci and trialeurodes vaporariorum (homoptera: aleyrodidae). | a study of predation choices of macrolophus caliginosus wagner (heteroptera: miridae) late instars and adults, when offered various developmental stages (eggs and nymphs) of the recently established whitefly bemisia tabaci (gennadius) (homoptera: aleyrodidae), was made based on two preference indices. in addition, prey choices of late instars when presented with three ratios of trialeurodes vaporariorum (westwood) (homoptera: aleyrodidae) and b. tabaci at a similar developmental stage (eggs, you ... | 2006 | 16937666 |
| pcr-based detection and partial genome sequencing indicate high genetic diversity in bangladeshi begomoviruses and their whitefly vector, bemisia tabaci. | the population diversity of bangladeshi begomoviruses and their vector, bemisia tabaci was analysed by pcr-based detection and partial genome sequencing. b. tabaci adults and plants expressing symptoms of virus infection were collected from locations representing diverse agro-ecological regions of the country. universal and species-specific primers were used to detect begomoviruses in seven crops (chilli, okra, papaya, pumpkin, sponge gourd, tomato and yardlong bean) and two common weeds (agerat ... | 2007 | 16927121 |
| effectiveness of two insect growth regulators against bemisia tabaci (gennadius) (homoptera: aleyrodidae) and helicoverpa armigera (hübner) (lepidoptera: noctuidae) and their impact on population densities of arthropod predators in cotton in pakistan. | field efficacies of two insect growth regulators (igrs) at two recommended application rates, buprofezin at 370 and 555 g ai ha(-1) and lufenuron at 37 and 49 g ai ha(-1), were determined against the sweet potato whitefly, bemisia tabaci (gennadius), and the cotton bollworm, helicoverpa armigera (hübner), in experimental plots of cotton at the directorate of cotton research, faisalabad, pakistan. adverse effects of the igrs on populations of associated arthropod predators, namely geocorids, chry ... | 2006 | 16862616 |
| post-transcriptional gene silencing in controlling viruses of the tomato yellow leaf curl virus complex. | tomato yellow leaf curl disease (tylcd) is caused by a group of geminiviruses that belong to the tomato yellow leaf curl virus (tylcv) complex and are transmitted by the whitefly (bemisia tabaci genn.). the disease causes great yield losses in many countries throughout the mediterranean region and the middle east. in this study, the efficacy of post-transcriptional gene silencing (ptgs) to control the disease caused by tylcv complex was investigated. non-coding conserved regions from the genome ... | 2006 | 16862387 |