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densities of eggs and nymphs and percent parasitism of bemisia tabaci (hemiptera: aleyrodidae) on common weeds in west central florida.the density of eggs and nymphs of bemisia tabaci (gennadius) biotype b and the percent parasitism of the nymphs were measured from specimens collected on nine species of weeds, commonly found in west central florida during the spring and summer of 2012 and 2013. the weeds were direct seeded in 2012 and grown as transplants in 2013 for randomized complete block design experiments. the leaf area of each whole-plant sample was measured and the b. tabaci density parameters were converted to numbers ...201426462945
the immune strategy and stress response of the mediterranean species of the bemisia tabaci complex to an orally delivered bacterial pathogen.the whitefly, bemisia tabaci, a notorious agricultural pest, has complex relationships with diverse microbes. the interactions of the whitefly with entomopathogens as well as its endosymbionts have received great attention, because of their potential importance in developing novel whitefly control technologies. to this end, a comprehensive understanding on the whitefly defense system is needed to further decipher those interactions.201424722540
torradoviruses are transmitted in a semi-persistent and stylet-borne manner by three whitefly vectors.members of the genus torradovirus (family secoviridae, type species tomato torrado virus, totv) are spherical plant viruses transmitted by the whitefly species trialeurodes vaporariorum and bemisia tabaci. knowledge on the mode of vector transmission is lacking for torradoviruses. here, the mode of transmission was determined for tomato marchitez virus (tomarv). a minimal acquisition access period (aap) and inoculation access period (iap) of approximately 2h each was required for its transmissio ...201424342139
synergistic manipulations of plant and insect defences.it has been demonstrated previously that cis-jasmone acts as an elicitor of plant defence mechanism(s) by inducing secondary metabolism. it has also been demonstrated that temporal synergism can result in hypersensitive insect pests due to the inhibition of metabolic enzymes.201423653417
eugenol enhances the resistance of tomato against tomato yellow leaf curl virus.tomato yellow leaf curl virus disease (tylcvd) causes severe to economic losses in tomato crops in china. the control of tylcvd is based primarily on the use of synthetic insecticide to control its vector whitefly (bemisia tabaci). to look for an alternative method for disease control, we investigated the effect of eugenol on controlling tylcvd. the potential of eugenol to trigger systemic acquired resistance (sar) in tomato (jiangsu 14) plants against tylcv was also investigated.201423852671
new insecticides for management of tomato yellow leaf curl, a virus vectored by the silverleaf whitefly, bemisia tabaci.greenhouse studies using a randomized complete block design were carried out to evaluate the effect of six insecticides on transmission of tomato yellow leaf curl virus (tylcv) by the silverleaf whitefly, bemisia tabaci biotype b gennadius (hemiptera: aleyrodidae) to tomato, lycopersicon esculentum (miller) (solanales: solanaceae), seedlings that were inoculated with whiteflies from a tylcv colony in cages 3, 7, or 14 d after treatment with insecticide. the purpose was to reveal differences in r ...201425368089
effects of plant virus and its insect vector on encarsia formosa, a biocontrol agent of whiteflies.in this study, we investigated the tritrophic interactions among a persistently transmitted plant virus, tomato yellow leaf curl virus (tylcv), its insect vector, the sweetpotato whitefly bemisia tabaci, and a parasitoid, encarsia formosa gahan, one of the most extensively used biological control agents. as an emerging invasive pest worldwide, the two most damaging whiteflies are b. tabaci b and q cryptic species. on healthy tomato plants, parasitoid-induced mortality was significantly higher in ...201425096549
tomato yellow leaf curl virus benefits population growth of the q biotype of bemisia tabaci (gennadius) (hemiptera: aleyrodidae).plant viruses can directly influence their insect vectors, and indirectly through their shared host plant, altering their behavior and performance in a mutualistic or rather antagonistic manner. one of the most studied begomovirus, tomato yellow leaf curl virus (tylcv), may also facilitate the expansion of its vector, the whitefly bemisia tabaci (gennadius). considering the likely expansion of the disease and its major vector, we studied the direct and the indirect effects of a mediterranean iso ...201427193818
three-way interactions between the tomato plant, tomato yellow leaf curl virus, and bemisia tabaci (hemiptera: aleyrodidae) facilitate virus spread.plant defense responses can greatly affect plant viruses and their herbivore vectors. the current article reports on plant defense responses involving jasmonic acid (ja), salicylic acid (sa), and proteinase inhibitor (pi) in the three-way interaction between tomato plants, tomato yellow leaf curl virus, and the whitefly bemisia tabaci (gennadius) (hemiptera: aleyrodidae). the results showed that feeding by viruliferous b. tabaci increases the longevity and fecundity of nonviruliferous b. tabaci ...201425026648
bemisia tabaci q carrying tomato yellow leaf curl virus strongly suppresses host plant defenses.the concurrence of tomato yellow leaf curl virus (tylcv) with the spread of its vector bemisia tabaci q rather than b in china suggests a more mutualistic relationship between tylcv and q. here, we investigated the hypothesis that viruliferous b and q have different effects on plant defenses. we found the fecundity of nonviruliferous b, nonviruliferous q, viruliferous q and viruliferous b was 11.080, 12.060, 10.760, and 11.220 respectively on plants previously attacked by the other biotype, howe ...201424912756
upregulation of probing- and feeding-related behavioural frequencies in bemisia tabaci upon acquisition of tomato yellow leaf curl virus.the behaviour of insect vectors can be altered by the acquisition of plant viruses. bemisia tabaci, which is the vector of tomato yellow leaf curl virus (tylcv), causes damage to susceptible tomato cultivars. here, the frequencies of several behavioural characteristics related to probing and feeding that are exhibited by non-viruliferous (nv) and tylcv-viruliferous (v) adult b. tabaci were compared using a sandwich-type parafilm cage.201424831051
rapid spread of a recently introduced virus (tomato yellow leaf curl virus) and its vector bemisia tabaci (hemiptera: aleyrodidae) in liaoning province, china.in liaoning province, china, tomato yellow leaf curl virus (tylcv) was first detected in 2009 and in only four counties. to quantify the spread of tylcv and to identify potential factors influencing its spread in liaoning province, we assayed for tylcv within 1,055 whiteflies (bemisia tabaci (gennadius) complex) from 74 populations and 29 counties in 2011. the b. tabaci species of these individuals was determined based on molecular markers. tylcv was found in 13 counties (donggang, liaoyang, kaz ...201424665690
a review of the mechanisms and components that determine the transmission efficiency of tomato yellow leaf curl virus (geminiviridae; begomovirus) by its whitefly vector.begomoviruses are a group of icosahedral single stranded dna viruses exclusively transmitted by the sweet potato whitefly bemisia tabaci in a persistent, circulative manner. in this mode of transmission, begomoviruses are acquired by their insect vector as intact virions from the plant phloem, move along the food canal, foregut and esophagus and reach the midgut where they are absorbed into the hemolymph via the filter chamber. the filter chamber is the site where most of the ingested food is fi ...201424508344
expression and functional characterisation of a soluble form of tomato yellow leaf curl virus coat protein.tomato yellow leaf curl virus (tylcv), a member of the genus begomovirus within the family geminiviridae, is an important pathogen of tomato in many tropical, subtropical and temperate regions. tylcv is exclusively transmitted by the whitefly bemisia tabaci in a circulative manner. the viral coat protein (cp) has been assumed to play important roles in the entry of tylcv into the insect midgut cells.201424488592
degradation mechanisms of the tomato yellow leaf curl virus coat protein following inoculation of tomato plants by the whitefly bemisia tabaci.tomato yellow leaf curl virus (tylcv) is a begomovirus infecting tomato cultures worldwide. tylcv is transmitted to plants by the whitefly bemisia tabaci. once in the plant, the virus is subjected to attack by the host-plant defences, which may include sequestration in aggregates, proteolysis, ubiquitination, 26s proteasome degradation and autophagy. elucidating how the virus avoids destruction will make it possible to understand infection and possibly devise countermeasures.201424464776
a bead-based suspension array for the multiplexed detection of begomoviruses and their whitefly vectors.bead-based suspension array systems enable simultaneous fluorescence-based identification of multiple nucleic acid targets in a single reaction. this study describes the development of a novel approach to plant virus and vector diagnostics, a multiplexed 7-plex array that comprises a hierarchical set of assays for the simultaneous detection of begomoviruses and bemisia tabaci, from both plant and whitefly samples. the multiplexed array incorporates genus, species and strain-specific assays, offe ...201424388931
lamium amplexicaule (lamiaceae): a weed reservoir for tomato yellow leaf curl virus (tylcv) in korea.after the first identification of tomato yellow leaf curl virus (tylcv) in the southern part of korea in 2008, tylcv has rapidly spread to tomato farms in most regions of korea. from 2008 to 2010, a survey of natural weed hosts that could be reservoirs of tylcv was performed in major tomato production areas of korea. about 530 samples were collected and identified as belonging to 25 species from 11 families. pcr and southern hybridization were used to detect tylcv in samples, and replicating for ...201424327090
virulence factors of geminivirus interact with myc2 to subvert plant resistance and promote vector performance.a pathogen may cause infected plants to promote the performance of its transmitting vector, which accelerates the spread of the pathogen. this positive effect of a pathogen on its vector via their shared host plant is termed indirect mutualism. for example, terpene biosynthesis is suppressed in begomovirus-infected plants, leading to reduced plant resistance and enhanced performance of the whiteflies (bemisia tabaci) that transmit these viruses. although begomovirus-whitefly mutualism has been k ...201425490915
specific cells in the primary salivary glands of the whitefly bemisia tabaci control retention and transmission of begomoviruses.the majority of plant viruses are vectored by arthropods via persistent-circulative or noncirculative transmission. previous studies have shown that specific binding sites for noncirculative viruses reside within the stylet or foregut of insect vectors, whereas the transmission mechanisms of circulative viruses remain ambiguous. here we report the critical roles of whitefly primary salivary glands (psgs) in the circulative transmission of two begomoviruses. the middle east asia minor 1 (meam1) s ...201425210181
molecular characterization of soluble and membrane-bound trehalases of the whitefly, bemisia tabaci.trehalases (tres) have been demonstrated to be the key enzymes that are involved in various trehalose-associated physiological processes in insects. however, little attention has been devoted to the tres in the whitefly, bemisia tabaci. in this study, a soluble tre (bttre-1) and a membrane-bound tre (bttre-2) were cloned in the invasive cryptic species middle east-asia minor 1 (meam1) of the whitefly b. tabaci complex. alignment of deduced amino acids sequences of both bttres revealed that they ...201424610752
feeding on a begomovirus-infected plant enhances fecundity via increased expression of an insulin-like peptide in the whitefly, meam1.the middle east-minor 1 cryptic species (meam1), bemisia tabaci (gennadius) is a globally invasive pest. it spreads widely due to its high fecundity and mutualistic interactions with the virus they vector. feeding on virus (tomato yellow leaf curl china virus, tylccnv)-infected host plants improves their fecundity, however, the key factor regulating the signaling transduction in reproduction of whitefly remains to be identified. here, we cloned a full length cdna encoding an insulin-like peptide ...201424532462
characterization of the symbiont rickettsia in the mirid bug nesidiocoris tenuis (reuter) (heteroptera: miridae).nesidiocoris tenuis (reuter) (heteroptera: miridae) is an omnivorous insect used for biological control. augmentative release and conservation of n. tenuis have been used for pest control in tomato crops. intracellular bacterial symbionts of arthropods are common in nature and have diverse effects on their hosts; in some cases they can dramatically affect biological control. fingerprinting methods showed that the symbiotic complex associated with n. tenuis includes wolbachia and rickettsia. rick ...201425062354
infectious cdna clones of the crinivirus tomato chlorosis virus are competent for systemic plant infection and whitefly-transmission.tomato chlorosis virus (tocv) (genus crinivirus, family closteroviridae) causes important emergent diseases in tomato and other solanaceous crops. tocv is not transmitted mechanically and is naturally transmitted by whiteflies. the tocv genome consists of two molecules of linear, positive-sense rna encapsidated into long flexuous virions. we present the construction of full-length cdna clones of the tocv genome (rna1 and rna2) fused to the sp6 rna polymerase promoter and under the control of the ...201425113907
epidemiology and genetic diversity of criniviruses associated with tomato yellows disease in greece.tomato chlorosis virus (tocv) and tomato infectious chlorosis virus (ticv) are two whitefly transmitted viruses which are classified in the genus crinivirus of the family closteroviridae. both induce similar yellowing symptoms in tomato and are responsible for severe economic losses. tocv is transmitted by bemisia tabaci gennadious, trialeurodes vaporariorum westwood and trialeurodes abutilonea haldeman, whereas ticv is transmitted only by t. vaporariorum. an extensive study was conducted during ...201424370865
molecular detection and partial characterization of a begomovirus causing leaf curl disease of potato in sub-himalayan west bengal, india.the characteristic disease symptoms of apical leaf curl, crinkled leaves and conspicuous mosaic were observed in potato plants grown in areas of coochbehar, one of the distinct agroclimatic zones of sub-himalayan west bengal. whitefly (bemisia tabaci) population was also observed in and around the infected plants. the characteristic disease symptoms and presence of whitefly (bemisia tabaci) population indicated the possibility of begomovirus infection. total dna was extracted from infected sampl ...201424813019
microarray analysis of tomato plants exposed to the nonviruliferous or viruliferous whitefly vector harboring pepper golden mosaic virus.plants are routinely exposed to biotic and abiotic stresses to which they have evolved by synthesizing constitutive and induced defense compounds. induced defense compounds are usually made, initially, at low levels; however, following further stimulation by specific kinds of biotic and abiotic stresses, they can be synthesized in relatively large amounts to abate the particular stress. cdna microarray hybridization was used to identify an array of genes that were differentially expressed in tom ...201425525099
rna viral metagenome of whiteflies leads to the discovery and characterization of a whitefly-transmitted carlavirus in north america.whiteflies from the bemisia tabaci species complex have the ability to transmit a large number of plant viruses and are some of the most detrimental pests in agriculture. although whiteflies are known to transmit both dna and rna viruses, most of the diversity has been recorded for the former, specifically for the begomovirus genus. this study investigated the total diversity of dna and rna viruses found in whiteflies collected from a single site in florida to evaluate if there are additional, p ...201424466220
assessing transmission of crop diseases by insect vectors in a landscape context.theory indicates that landscape composition affects transmission of vector-borne crop diseases, but few empirical studies have investigated how landscape composition affects plant disease epidemiology. since 2006, bemisia tabaci (gennadius) has vectored the cucurbit yellow stunting disorder virus (cysdv) to cantaloupe and honeydew melons (cucumis melo l.) in the southwestern united states and northern mexico, causing significant reductions in yield of fall melons and increased use of insecticide ...201424665679
isolation and identification of culturable bacteria from honeydew of whitefly, bemisia tabaci (g.) (hemiptera: aleyrodidae).bemisia tabaci (g.) is an important pest and a vector of gemini viruses infecting plants. during the process of feeding b. tabaci excretes honeydew which is rich in nutrients, and an excellent medium for microbial growth. recent report proved that volatile emitted by the honeydew associated bacteria of aphid, acyrthosiphon pisum harris was involved in natural enemy calling. thus understanding the honeydew associated bacteria is of paramount importance from the non-chemical method of insect pest ...201425606395
transcriptomic dissection of sexual differences in bemisia tabaci, an invasive agricultural pest worldwide.sex difference involving chromosomes and gene expression has been extensively documented. in this study, the gender difference in the sweetpotato whitefly bemisia tabaci was investigated using illumina-based transcriptomic analysis. gender-based rnaseq data produced 27 gb reads, and subsequent de novo assembly generated 93,948 transcripts with a n50 of 1,853 bp. a total of 1,351 differentially expressed genes were identified between male and female b. tabaci, and majority of them were female-bia ...201424526031
location of symbionts in the whitefly bemisia tabaci affects their densities during host development and environmental stress.bacterial symbionts often enhance the physiological capabilities of their arthropod hosts and enable their hosts to expand into formerly unavailable niches, thus leading to biological diversification. many arthropods, including the worldwide invasive whitefly bemisia tabaci, have individuals simultaneously infected with symbionts of multiple genera that occur in different locations in the host. this study examined the population dynamics of symbionts that are located in different areas within b. ...201424632746
female-biased symbionts and tomato yellow leaf curl virus infections in bemisia tabaci.the female-biased infection of facultative symbionts has been found in bemisia tabaci; however, whether there are any differences in tomato yellow leaf curl virus (tylcv) and obligate symbiont infection rates between females and males is unknown. determining whether such differences exist would be very important for understanding the spread of the plant virus and of the symbionts. we compared both symbiont infection types, including obligate and facultative symbionts, and the rates of tylcv infe ...201424465416
the genome of cardinium cbtq1 provides insights into genome reduction, symbiont motility, and its settlement in bemisia tabaci.many insects harbor inherited bacterial endosymbionts. although some of them are not strictly essential and are considered facultative, they can be a key to host survival under specific environmental conditions, such as parasitoid attacks, climate changes, or insecticide pressures. the whitefly bemisia tabaci is at the top of the list of organisms inflicting agricultural damage and outbreaks, and changes in its distribution may be associated to global warming. in this work, we have sequenced and ...201424723729
implication of the bacterial endosymbiont rickettsia spp. in interactions of the whitefly bemisia tabaci with tomato yellow leaf curl virus.numerous animal and plant viruses are transmitted by arthropod vectors in a persistent, circulative manner. tomato yellow leaf curl virus (tylcv) is transmitted by the sweet potato whitefly bemisia tabaci. we report here that infection with rickettsia spp., a facultative endosymbiont of whiteflies, altered tylcv-b. tabaci interactions. a b. tabaci strain infected with rickettsia acquired more tylcv from infected plants, retained the virus longer, and exhibited nearly double the transmission effi ...201424600010
the facultative symbiont rickettsia protects an invasive whitefly against entomopathogenic pseudomonas syringae strains.facultative endosymbionts can benefit insect hosts in a variety of ways, including context-dependent roles, such as providing defense against pathogens. the role of some symbionts in defense may be overlooked, however, when pathogen infection is transient, sporadic, or asymptomatic. the facultative endosymbiont rickettsia increases the fitness of the sweet potato whitefly (bemisia tabaci) in some populations through mechanisms that are not yet understood. in this study, we investigated the role ...201425217020
diversity and localization of bacterial endosymbionts from whitefly species collected in brazil.whiteflies (hemiptera: aleyrodidae) are sap-sucking insect pests, and some cause serious damage in agricultural crops by direct feeding and by transmitting plant viruses. whiteflies maintain close associations with bacterial endosymbionts that can significantly influence their biology. all whitefly species harbor a primary endosymbiont, and a diverse array of secondary endosymbionts. in this study, we surveyed 34 whitefly populations collected from the states of sao paulo, bahia, minas gerais an ...201425259930
quantification and localization of watermelon chlorotic stunt virus and tomato yellow leaf curl virus (geminiviridae) in populations of bemisia tabaci (hemiptera, aleyrodidae) with differential virus transmission characteristics.bemisia tabaci (gennadius) is one of the economically most damaging insects to crops in tropical and subtropical regions. severe damage is caused by feeding and more seriously by transmitting viruses. those of the genus begomovirus (geminiviridae) cause the most significant crop diseases and are transmitted by b. tabaci in a persistent circulative mode, a process which is largely unknown. to analyze the translocation and to identify critical determinants for transmission, two populations of b. t ...201425365330
competitive ability and fitness differences between two introduced populations of the invasive whitefly bemisia tabaci q in china.our long-term field survey revealed that the cardinium infection rate in bemisia tabaci q (also known as biotype q) population was low in shandong, china over the past few years. we hypothesize that (1) the cardinium-infected (c+) b. tabaci q population cannot efficiently compete with the cardinium-uninfected (c-) b. tabaci q population; (2) no reproductive isolation may have occurred between c+ and c-; and (3) the c- population has higher fitness than the c+ population.201424945699
influence of additives on the yield and pathogenicity of conidia produced by solid state cultivation of an isaria javanica isolate.recently, the q biotype of tobacco whitefly has been recognized as the most hazardous strain of bemisia tabaci worldwide, because of its increased resistance to some insecticide groups. as an alternative control agent, we selected an isaria javanica isolate as a candidate for the development of a mycopesticide against the q biotype of sweet potato whitefly. to select optimal mass production media for solid-state fermentation, we compared the production yield and virulence of conidia between 2 su ...201425606006
transcriptome profiling of the whitefly bemisia tabaci reveals stage-specific gene expression signatures for thiamethoxam resistance.bemisia tabaci has developed high levels of resistance to many insecticides including the neonicotinoids and there is strong evidence that for some compounds resistance is stage-specific. to investigate the molecular basis of b. tabaci resistance to the neonicotinoid thiamethoxam we used a custom whitefly microarray to compare gene expression in the egg, nymph and adult stages of a thiamethoxam-resistant strain (th-r) with a susceptible strain (th-s). gene ontology and bioinformatic analyses rev ...201323889345
characterization and comparative profiling of mirnas in invasive bemisia tabaci (gennadius) b and q.micrornas (mirnas) are small, conserved, non-coding rnas that post-transcriptionally regulate gene expression. bemisia tabaci (gennadius) b and q are two invasive and dominant whiteflies, and b. tabaci q has been displacing b in china. differences in biological traits (fecundity, host range, resistance to insecticides, etc.) as affected by mirnas might be involved in the displacement. in this study, we performed high-throughput sequencing to identify mirnas in b. tabaci b and q.201323527280
analysis of whitefly transcriptional responses to beauveria bassiana infection reveals new insights into insect-fungus interactions.the fungal pathogen, beauveria bassiana, is an efficient biocontrol agent against a variety of agricultural pests. a thorough understanding of the basic principles of insect-fungus interactions may enable the genetic modification of beauveria bassiana to enhance its virulence. however, the molecular mechanism of insect response to beauveria bassiana infection is poorly understood, let alone the identification of fungal virulent factors involved in pathogenesis.201323861870
transcriptomic and proteomic responses of sweetpotato whitefly, bemisia tabaci, to thiamethoxam.the sweetpotato whitefly, bemisia tabaci (hemiptera: aleyrodidae), is one of the most widely distributed agricultural pests. although it has developed resistance to many registered insecticides including the neonicotinoid insecticide thiamethoxam, the mechanisms that regulate the resistance are poorly understood. to understand the molecular basis of thiamethoxam resistance, "omics" analyses were carried out to examine differences between resistant and susceptible b. tabaci at both transcriptiona ...201323671574
cloning and functional characterization of c-jun nh2-terminal kinase from the mediterranean species of the whitefly bemisia tabaci complex.c-jun nh2-terminal kinase (jnk) signaling is a highly conserved pathway that controls gene transcription in response to a wide variety of biological and environmental stresses. in this study, a jnk from the invasive mediterranean (med) species of the whitefly bemisia tabaci complex was cloned and characterized. the full-length jnk cdna of med consists of 1565 bp, with an 1176 bp open reading frame encoding 392 amino acids. comparison of jnk amino acid sequences among different species showed tha ...201323807503
molecular identification of ageratum enation virus, betasatellite and alphasatellite molecules isolated from yellow vein diseased amaranthus cruentus in india.natural occurrence of yellow vein disease on amaranthus cruentus was observed at lucknow, india in the year 2008. the causal virus was successfully transmitted through whiteflies (bemisia tabaci) from diseased a. cruentus to healthy seedlings of a. cruentus and other test species which indicated begomovirus infection. the begomovirus dna-a, betasatellite, and alphasatellite components associated with yellow vein disease were amplified by rolling circle amplification using ø-29 dna polymerase fro ...201323963765
update on the status of bemisia tabaci in the uk and the use of entomopathogenic fungi within eradication programmes.the sweetpotato whitefly bemisia tabaci (gennadius) (hemiptera: aleyrodidae) continues to be a serious threat to crops worldwide. the uk holds protected zone status against this pest and, as a result, b. tabaci entering on plant material is subjected to a policy of eradication. both b and q bemisia biotypes are now regularly intercepted entering the uk. with increasing reports of neonicotinoid resistance in both these biotypes, it is becoming more problematic to control/eradicate. therefore, alt ...201326464385
plant virus differentially alters the plant's defense response to its closely related vectors.the whitefly, bemisia tabaci (hemiptera: aleyrodidae), is one of the most widely distributed agricultural pests. in recent years, b. tabaci q has invaded china, and q has displaced b in many areas now. in a number of regions of the world, invasion by b and/or q has been followed by outbreaks of tomato yellow leaf curl virus (tylcv). our previous study showed tylcv directly and indirectly modified the feeding behavior of b. tabaci in favor of q rather than b.201324391779
enhanced methanol production in plants provides broad spectrum insect resistance.plants naturally emit methanol as volatile organic compound. methanol is toxic to insect pests; but the quantity produced by most of the plants is not enough to protect them against invading insect pests. in the present study, we demonstrated that the over-expression of pectin methylesterase, derived from arabidopsis thaliana and aspergillus niger, in transgenic tobacco plants enhances methanol production and resistance to polyphagous insect pests. methanol content in the leaves of transgenic pl ...201324223989
inoculation of tomato plants with rhizobacteria enhances the performance of the phloem-feeding insect bemisia tabaci.in their natural environment, plants experience multiple biotic interactions and respond to this complexity in an integrated manner. therefore, plant responses to herbivory are flexible and depend on the context and complexity in which they occur. for example, plant growth promoting rhizobacteria (pgpr) can enhance plant growth and induce resistance against microbial pathogens and herbivorous insects by a phenomenon termed induced systemic resistance (isr). in the present study, we investigated ...201323964283
the evolution of genomic instability in the obligate endosymbionts of whiteflies.many insects depend on ancient associations with intracellular bacteria to perform essential metabolic functions. these endosymbionts exhibit striking examples of convergence in genome architecture, including a high degree of structural stability that is not typical of their free-living counterparts. however, the recently sequenced genome of the obligate whitefly endosymbiont portiera revealed features that distinguish it from other ancient insect associates, such as a low gene density and the p ...201323542079
comparison of the genome sequences of "candidatus portiera aleyrodidarum" primary endosymbionts of the whitefly bemisia tabaci b and q biotypes."candidatus portiera aleyrodidarum" is the primary endosymbiont of whiteflies. we report two complete genome sequences of this bacterium from the worldwide invasive b and q biotypes of the whitefly bemisia tabaci. differences in the two genome sequences may add insights into the complex differences in the biology of both biotypes.201323315735
characterization of a new begomovirus and a beta satellite associated with the leaf curl disease of french bean in northern india.begomoviruses are emerging as serious threat to many crops throughout the world particularly in tropical and sub-tropical regions. a leaf curl disease with symptoms typical of infection by many begomoviruses was observed in french bean (phaseolus vulgaris) at kanpur, india, during 2010-2012. the disease caused downward leaf curling and made the plants unproductive. the disease was transmitted from infected to healthy plants through whitefly (bemisia tabaci). the products of five samples digested ...201323054434
a plant virus manipulates the behavior of its whitefly vector to enhance its transmission efficiency and spread.plant viruses can produce direct and plant-mediated indirect effects on their insect vectors, modifying their life cycle, fitness and behavior. viruses may benefit from such changes leading to enhanced transmission efficiency and spread. in our study, female adults of bemisia tabaci were subjected to an acquisition access period of 72 h in tomato yellow leaf curl virus (tylcv)-infected and non-infected tomato plants to obtain viruliferous and non-viruliferous whiteflies, respectively. insects th ...201323613872
host range and genetic diversity of croton yellow vein mosaic virus, a weed-infecting monopartite begomovirus causing leaf curl disease in tomato.croton yellow vein mosaic virus (cyvmv) is a widely occurring begomovirus in croton bonplandianum, a common weed in the indian subcontinent. in this study, cyvmv (genus begomovirus, family geminiviridae) was transmitted by whiteflies (bemisia tabaci) to as many as 35 plant species belonging to 11 families, including many vegetables, tobacco varieties, ornamentals and weeds. cyvmv produced bright yellow vein symptoms in croton, whereas in all the other host species, the virus produced leaf curl s ...201323096697
the role of bacterial chaperones in the circulative transmission of plant viruses by insect vectors.persistent circulative transmission of plant viruses involves complex interactions between the transmitted virus and its insect vector. several studies have shown that insect vector proteins are involved in the passage and the transmission of the virus. interestingly, proteins expressed by bacterial endosymbionts that reside in the insect vector, were also shown to influence the transmission of these viruses. thus far, the transmission of two plant viruses that belong to different virus genera w ...201323783810
identification, characterization and expression of a defensin-like antifungal peptide from the whitefly bemisia tabaci (gennadius) (hemiptera: aleyrodidae).defensins are a class of small and diverse cysteine-rich proteins which have broad-spectrum antimicrobial activities. we identified and characterized a full-length cdna encoding a putative defensin-like peptide from the whitefly bemisia tabaci by race and quantitative real-time (qrt)-pcr. the full-length cdna, named btdef, was 388 bp long and contained an open reading frame of 228 bp. the putative mature btdef had 46 amino acids with a molecular weight of 5.06 kda. the deduced amino acid sequenc ...201323496414
cloning, expression and characterization of mitochondrial manganese superoxide dismutase from the whitefly, bemisia tabaci.a mitochondrial manganese superoxide dismutase from an invasive species of the whitefly bemisia tabaci complex (bt-mmnsod) was cloned and analyzed. the full length cdna of bt-mmnsod is 1210 bp with a 675 bp open reading frame, corresponding to 224 amino acids, which include 25 residues of the mitochondrial targeting sequence. compared with various vertebrate and invertebrate animals, the mnsod signature (dvwehayy) and four conserved amino acids for manganese binding (h54, h102, d186 and h190) we ...201323296268
natural association of two different betasatellites with sweet potato leaf curl virus in wild morning glory (ipomoea purpurea) in india.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 ...201323529301
detoxification activity and energy cost is attenuated in whiteflies feeding on tomato yellow leaf curl china virus-infected tobacco plants.the begomovirus tomato yellow leaf curl china virus (tylccnv) can benefit its vector, the whitefly bemisia tabaci, through suppressing the defences of their shared host plants. however, the mechanisms of this vector-virus mutualism remain largely unknown on the insect side of the interaction. here, we compared the transcriptional profiles of female adult whiteflies of b. tabaci middle east-asia minor 1 feeding on tylccnv-free and tylccnv-infected tobacco plants using the next-generation sequenci ...201323889516
tomato spotted wilt virus infection reduces the fitness of a nonvector herbivore on pepper.plant pathogens and insect herbivores often share hosts under natural conditions. hence, pathogen-induced changes in a host plant can affect the herbivore and vice versa. even though plant viruses are ubiquitous in the field, little is known about plant-mediated interactions between viruses and nonvector herbivores. here we tested whether the performance of the sweet potato whitefly, bemisia tabaci (gennadius) biotype q, was altered when raised on pepper infected with tomato spotted wilt virus ( ...201323786083
a new begomovirus-betasatellite complex is associated with chilli leaf curl disease in sri lanka.leaf curl disease of chilli (lcdc) is a major constraint in production of chilli in the indian subcontinent. the objective of this study was to identify the begomovirus species occurring in chilli in sri lanka, where the lcdc was initially recorded in 1938. the virus samples were collected from the north central province, the major chilli growing region in sri lanka with a history of epidemic prevalence of lcdc. the virus could be readily transmitted by bemisia tabaci to chilli, tomato and tobac ...201323090833
facultative symbiont hamiltonella confers benefits to bemisia tabaci (hemiptera: aleyrodidae), an invasive agricultural pest worldwide.bacterial symbionts infect most insect species, including important pests such as whitefly, bemisia tabaci (gennadius) (hemiptera: aleyrodidae), and often exert important effects on host ecology. the facultative symbiont hamiltonella is found at high frequencies in the b. tabaci med (type: mediterranean-med) in china. the prevalence of this symbiont in natural populations suggests beneficial effects of infection or manipulation of host reproduction. to date, however, no empirical studies on the ...201324280594
tomato yellow leaf curl virus alters the host preferences of its vector bemisia tabaci.bemisia tabaci, the whitefly vector of tomato yellow leaf curl virus (tylcv), seriously reduces tomato production and quality. here, we report the first evidence that infection by tylcv alters the host preferences of invasive b. tabaci b (middle east-minor asia 1) and q (mediterranean genetic group), in which tylcv-free b. tabaci q preferred to settle on tylcv-infected tomato plants over healthy ones. tylcv-free b. tabaci b, however, preferred healthy tomato plants to tylcv-infected plants. in c ...201324096821
recruitment of the host plant heat shock protein 70 by tomato yellow leaf curl virus coat protein is required for virus infection.a functional capsid protein (cp) is essential for host plant infection and insect transmission of tomato yellow leaf curl virus (tylcv) and other monopartite begomoviruses. we have previously shown that tylcv cp specifically interacts with the heat shock protein 70 (hsp70) of the virus insect vector, bemisia tabaci. here we demonstrate that during the development of tomato plant infection with tylcv, a significant amount of hsp70 shifts from a soluble form into insoluble aggregates. cp and hsp70 ...201323894631
virus infection of a weed increases vector attraction to and vector fitness on the weed.weeds are important in the ecology of field crops, and when crops are harvested, weeds often become the main hosts for plant viruses and their insect vectors. few studies, however, have examined the relationships between plant viruses, vectors, and weeds. here, we investigated how infection of the weed datura stramonium l. by tomato yellow leaf curl virus (tylcv) affects the host preference and performance of the tylcv vector, bemisia tabaci (gennadius) q. the results of a choice experiment indi ...201323872717
differential effects of an exotic plant virus on its two closely related vectors.concurrent spread of tomato yellow leaf curl virus (tylcv) with invasion of bemisia tabaci q rather than b in china suggests a more mutualistic relationship between tylcv and q than b. to assess this hypothesis, we quantified the impacts of tylcv on the performance and competitiveness of b and q in the laboratory. the results showed that relative to their non-infected counterparts feeding on cotton (a non-host for tylcv), infected b exhibited significant reductions in life-history traits, wherea ...201323864010
highly sensitive serological methods for detecting tomato yellow leaf curl virus in tomato plants and whiteflies.tomato yellow leaf curl virus (tylcv) is a member of the genus begomovirus in the family geminiviridae, which causes severe losses in tomato production in tropic and subtropic regions.201323647724
within-host dynamics of the emergence of tomato yellow leaf curl virus recombinants.tomato yellow leaf curl virus (tylcv) is a highly damaging begomovirus native to the middle east. tylcv has recently spread worldwide, recombining with other begomoviruses. recent analysis of mixed infections between tylcv and tomato leaf curl comoros begomovirus (tolckmv) has shown that, although natural selection preserves certain co-evolved intra-genomic interactions, numerous and diverse recombinants are produced at 120 days post-inoculation (dpi), and recombinant populations from different ...201323472190
insect symbiont facilitates vector acquisition, retention, and transmission of plant virus.tomato yellow leaf curl virus (tylcv) was first detected in china in 2006, following the introduction of bemisia tabaci q into china in 2003. since then, the incidence of tylcv in tomato fields in china has greatly increased as has the abundance and distribution of q whiteflies containing the bacterial symbiont hamiltonella with high frequency. this suggested that the symbiont hamiltonella might associate with the transmission efficiency of tylcv by the whitefly vector. here we report the first ...201323455639
multiple forms of vector manipulation by a plant-infecting virus: bemisia tabaci and tomato yellow leaf curl virus.for many insect-vectored plant viruses, the relationship between feeding behavior and vector competence may prove integral to an understanding of the epidemiology of the resulting plant disease. while plant-infecting viruses are well known to change host plant physiology in a way that makes them more attractive to vectors, viral manipulation of the vectors themselves has only recently been reported. previous research suggested that the rapid spread of tomato yellow leaf curl virus (tylcv) throug ...201323408638
formation of stylet sheaths in āere (in air) from eight species of phytophagous hemipterans from six families (suborders: auchenorrhyncha and sternorrhyncha).stylet sheath formation is a common feature among phytophagous hemipterans. these sheaths are considered essential to promote a successful feeding event. stylet sheath compositions are largely unknown and their mode of solidification remains to be elucidated. this report demonstrates the formation and solidification of in āere (in air) produced stylet sheaths by six hemipteran families: diaphorina citri (psyllidae, asian citrus psyllid), aphis nerii (aphididae, oleander/milkweed aphid), toxopter ...201323638086
insecticide resistance in bemisia tabaci gennadius (homoptera: aleyrodidae) and anopheles gambiae giles (diptera: culicidae) could compromise the sustainability of malaria vector control strategies in west africa.insecticides from the organophosphate (op) and pyrethroid (py) chemical families, have respectively, been in use for 50 and 30 years in west africa, mainly against agricultural pests, but also against vectors of human disease. the selection pressure, with practically the same molecules year after year (mainly on cotton), has caused insecticide resistance in pest populations such as bemisia tabaci, vector of harmful phytoviruses on vegetables. the evolution toward insecticide resistance in malari ...201323792227
molecular mechanisms associated with increased tolerance to the neonicotinoid insecticide imidacloprid in the dengue vector aedes aegypti.mosquitoes are vectors of several major human diseases and their control is mainly based on the use of chemical insecticides. resistance of mosquitoes to organochlorines, organophosphates, carbamates and pyrethroids led to a regain of interest for the use of neonicotinoid insecticides in vector control. the present study investigated the molecular basis of neonicotinoid resistance in the mosquito aedes aegypti. a strain susceptible to insecticides was selected at the larval stage with imidaclopr ...201323058251
arabidopsis thaliana plants with different levels of aliphatic- and indolyl-glucosinolates affect host selection and performance of bemisia tabaci.generalist insects show reduced selectivity when subjected to similar, but not identical, host plant chemical signatures. here, we produced transgenic arabidopsis thaliana plants that over-express genes regulating the aliphatic- and indolyl- glucosinolates biosynthetic pathways with either a constitutive (camv 35s) or a phloem-specific promoter (atsuc2). this allowed us to examine how exposure to high levels of aliphatic- or indolyl-glucosinolates in homogenous habitats (leaf cage apparatus cont ...201324190022
feeding by whiteflies suppresses downstream jasmonic acid signaling by eliciting salicylic acid signaling.phloem-feeding whiteflies in the species complex bemisia tabaci cause extensive crop damage worldwide. one of the reasons for their "success" is their ability to suppress the effectual jasmonic acid (ja) defenses of the host plant. however, little is understood about the mechanisms underlying whitefly suppression of ja-regulated defenses. here, we showed that the expression of salicylic acid (sa)-responsive genes (eds1 and pr1) in arabidopsis thaliana was significantly enhanced during feeding by ...201323604702
jasmonate and ethylene signaling mediate whitefly-induced interference with indirect plant defense in arabidopsis thaliana.upon herbivore attack, plants activate an indirect defense, that is, the release of a complex mixture of volatiles that attract natural enemies of the herbivore. when plants are simultaneously exposed to two herbivore species belonging to different feeding guilds, one herbivore may interfere with the indirect plant defense induced by the other herbivore. however, little is understood about the mechanisms underlying such interference. here, we address the effect of herbivory by the phloem-feeding ...201323311965
establishment of an in vitro method for evaluating whitefly resistance in tomato.an accurate and simple evaluation method is crucial for identifying whitefly resistance in tomato breeding. we developed an in vitro method for evaluating resistance of tomato leaves and tested this on wild and cultivated tomato varieties. we found that young leaves observed for whitefly oviposition after 8 hours provided appropriate comparative conditions. this method effectively distinguished resistance among tomato cultivars and wild species and also demonstrated significant difference in ovi ...201324273418
two cytochrome p450 genes are involved in imidacloprid resistance in field populations of the whitefly, bemisia tabaci, in china.the sweet potato whitefly, bemisia tabaci (gennadius) (hemiptera:aleyrodidae), is an invasive and damaging pest of field crops worldwide. the neonicotinoid insecticide imidacloprid has been widely used to control this pest. we assessed the species composition (b vs. q), imidacloprid resistance, and association between imidacloprid resistance and the expression of five p450 genes for 14-17 b. tabaci populations in 12 provinces in china. fifteen of 17 populations contained only b. tabaci q, and tw ...201324267696
population variability of bemisia tabaci (genn.) in different hosts.the silverleaf whitefly, bemisia tabaci (genn.) (hemiptera: aleyrodidae), is a cryptic species complex that contains some of the most damaging pests in tropical and subtropical regions. recent studies have indicated that this complex is composed of at least 24 distinct and morphologically indistinguishable species that mainly differ in their ability to transmit phytoviruses, adapt to hosts, and induce physiological changes in certain hosts. the importance of this species has been increasing worl ...201324222237
wind-borne dispersal of a parasitoid: the process, the model, and its validation.the aphelinid parasitoid eretmocerus hayati zolnerowich & rose (hymenoptera: aphelinidae) was recently released in australia as a biocontrol agent against the crop pest bemisia tabaci gennadius (hemiptera: aleyrodidae). it was found that the parasitoid can spread over several kilometers in a single generation and continue laying eggs for over a fortnight. a simple wind-advection model was fitted to emergence data from a first release between fassifern and kalbar, queensland, and its predictive a ...201324216288
activation of the phenylpropanoid pathway in nicotiana tabacum improves the performance of the whitefly bemisia tabaci via reduced jasmonate signaling.phloem-feeding insects can manipulate plant-induced resistance and are able to suppress effective jasmonic acid/ethylene (ja/et) defenses by the induction of inefficient salicylic acid (sa) based responses. as a result, activation of the phenylpropanoid biosynthesis pathway in transgenic plants is anticipated to cause complex interactions between phloem-feeding insects and their host plants due to predicted contradiction between two defense forces: the toxicity of various phenylpropanoids and th ...201324204646
feeding experience of bemisia tabaci (hemiptera: aleyrodidae) affects their performance on different host plants.the sweetpotato whitefly, bemisia tabaci biotype b is extremely polyphagous with >600 species of host plants. we hypothesized that previous experience of the whitefly on a given host plant affects their host selection and performance on the plants without previous experience. we investigated the host selection for feeding and oviposition of adults and development and survival of immatures of three host-plant-experienced populations of b. tabaci, namely bemisia-eggplant, bemisia-tomato and bemisi ...201324146985
is agriculture driving the diversification of the bemisia tabaci species complex (hemiptera: sternorrhyncha: aleyrodidae)?: dating, diversification and biogeographic evidence revealed.humans and insect herbivores are competing for the same food crops and have been for thousands of years. despite considerable advances in crop pest management, losses due to insects remain considerable. the global homogenisation of agriculture has supported the range expansion of numerous insect pests and has been driven in part by human-assisted dispersal supported through rapid global trade and low-cost air passenger transport. one of these pests, is the whitefly, bemisia tabaci, a cryptic spe ...201324138220
plant-mediated changes in the feeding behavior of an invasive whitefly.the invasive whitefly bemisia tabaci (gennadius) is a worldwide pest of agricultural crops that feeds on a wide variety of host plants. although host plant preference is known to vary among b. tabaci biotypes, far less is known about the potential for intraspecific divergence caused by long-term isolation on a single species of host plant. we tested the hypothesis that multigenerational isolation of b. tabaci b, a biotype that has been well-established in china for nearly two decades, on three d ...201324073848
transmission efficiency of tomato apex necrosis virus by bemisia tabaci (hemiptera: aleyrodidae) biotype b in tomato.tomato apex necrosis virus (toanv) is a new virus that causes important damage in tomato crops from the culiacan valley, sinaloa, mexico. to understand the relationship between toanv and its vector bermisia tabaci (hemiptera: aleyrodidae) (gennadius) biotype b, laboratory and greenhouse trials were completed to: 1) determine the acquisition and inoculation access periods of toanv by b. tabaci from tomato to tomato, 2) understand the transmission efficiency at different b. tabaci population densi ...201324020266
yield and fibre quality associated with cotton leaf curl disease of bt-cotton in punjab.cotton leaf curl disease (clcud), caused by gemini virus and transmitted through whitefly (bemisia tabaci) is a serious problem in northern india, affecting the productivity to a great extent. depending upon the severity of infection in susceptible varieties, the disease can cause upto 90.0 % yield losses besides this, it also causes deterioration in fibre quality. the objective of the present study was to determine the effect of cotton leaf curl disease on seed cotton yield and fibre characters ...201324006816
comparative studies on the effects of bt-transgenic and nontransgenic cotton on arthropod diversity, seedcotton yield and bollworms control.the effectiveness of commercial bt-cotton in pest management, influence on arthropod diversity, natural enemies, and toxin flow in the insect fauna under field conditions were studied keeping in view the need to assess bioefficacy and biosafety of bt-transgenic cotton. there were no significant differences in oviposition by helicoverpa armigera on bt-transgenic and non-transgenic cottons (9.2 versus 9.6 eggs plants(-100)), while the numbers of h. armigera larvae were significantly more on non-tr ...201324006809
differences in insect resistance between tomato species endemic to the galapagos islands.the galapagos islands constitute a highly diverse ecosystem and a unique source of variation in the form of endemic species. there are two endemic tomato species, solanum galapagense and s. cheesmaniae and two introduced tomato species, s. pimpinellifolium and s. lycopersicum. morphologically the two endemic tomato species of the galapagos islands are clearly distinct, but molecular marker analysis showed no clear separation. tomatoes on the galapagos are affected by both native and exotic herbi ...201323972016
the bemisia tabaci species complex: additions from different parts of the world.bemisia tabaci is one of the most threatening pests in many crops. we sequenced part of the mitochondrial cytochrome oxidase i gene from fifty whitefly populations collected in indonesia, thailand, india and china. nineteen unique sequences (haplotypes) of the cytochrome oxidase i were identified in these populations. they were combined with sequences available in databases, resulting in a total of 407 haplotypes and analyzed together with nine outgroup accessions. a phylogenetic tree was calcul ...201323955997
multiple generation effects of high temperature on the development and fecundity of bemisia tabaci (gennadius) (hemiptera: aleyrodidae) biotype b.insects are ectotherms and their ability to resist temperature stress is limited. the immediate effects of sub-lethal heat stress on insects are well documented, but longer-term effects of such stresses are rarely reported. in this study, survival, development and reproduction of the whitefly, bemisia tabaci (gennadius) (hemiptera: aleyrodidae) biotype b, were compared over five consecutive generations at 27, 31 and 35 °c and for one generation at 37 °c. both temperature and generation significa ...201323955949
diversity of secondary endosymbionts among different putative species of the whitefly bemisia tabaci.endosymbionts are important components of arthropod biology. the whitefly bemisia tabaci (gennadius) (hemiptera: aleyrodidae) is a cryptic species complex composed of ≥ 28 putative species. in addition to the primary endosymbiont portiera aleyrodidarum, six secondary endosymbionts (s-endosymbionts), hamiltonella, rickettsia, wolbachia, cardinium, arsenophonus and fritschea, have been identified in b. tabaci thus far. here, we tested five of the six s-endosymbiont lineages (excluding fritschea) f ...201323955860
high variation in single nucleotide polymorphisms (snps) and insertions/deletions (indels) in the highly invasive bemisia tabaci (gennadius) (hemiptera: aleyrodidae) middle east-asia minor 1 (meam1).bemisia tabaci (gennadius) (hemiptera: aleyrodidae) middle east-asia minor 1 (meam1) is invasive and adaptive to varied environments throughout the world. the adaptability is closely related to genomic variation such as single nucleotide polymorphisms (snps) and insertions/deletions (indels). in order to elucidate the feature of snps and indels in meam1, and reveal the association between snps/indels and adaptive capacity to various environments, a computational approach with qualitysnp was used ...201323949985
response of bemisia tabaci genn. (hemiptera: aleyrodidae) biotype b to genotypes of pepper capsicum annuum (solanales: solanaceae).bemisia tabaci genn. biotype b is a widely distributed plant pest that represents one of the major constraints for horticultural crop production. the purpose of the present work was to evaluate the oviposition preference, survivorship, and development of b. tabaci biotype b on semi-cultivated genotypes of capsicum annuum from southeast mexico. in free-choice experiments to evaluate the oviposition preference, lower number of eggs laid by b. tabaci biotype b was observed in the genotypes maax and ...201323949756
selection of endogenous reference genes for gene expression analysis in the mediterranean species of the bemisia tabaci (hemiptera: aleyrodidae) complex.quantitative real-time reverse transcription polymerase chain reaction is widely used for gene expression analysis, and robust normalization against stably expressed endogenous reference genes (ergs) is necessary to obtain accurate results. in this study, the stability of nine housekeeping genes of the sweetpotato whitefly, bemisia tabaci (hemiptera: aleyrodidae) mediterranean were evaluated in various conditions by quantitative real-time reverse transcription polymerase chain reaction using gen ...201323865213
detection of resistance, cross-resistance, and stability of resistance to new chemistry insecticides in bemisia tabaci (homoptera: aleyrodidae).resistance levels in whitefly, bemisia tabaci (gennadius) collections from cotton and sunflower (up to four districts) for five neonicotinoids and two insect growth regulators (igrs) were investigated for two consecutive years. based on the lc50(s), all collections showed slight to moderate levels of resistance for the tested insecticides compared with the laboratory susceptible population. the data also indicated that cotton and sunflower collections had similar resistance levels. in comparison ...201323865209
monitoring changes in bemisia tabaci (hemiptera: aleyrodidae) susceptibility to neonicotinoid insecticides in arizona and california.bemisia tabaci (gennadius) biotype b is a highly prolific and polyphagous whitefly that established in much of north america during the 1980s. neonicotinoid insecticides have been fundamental in regaining control over outbreak populations of b. tabaci, but resistance threatens their sustainability. susceptibility of b. tabaci in the southwestern united states to four neonicotinoid insecticides varied considerably across populations within each year over a 3 yr period. using a variability ratio o ...201323865208
effects of high-gossypol cotton on the development and reproduction of bemisia tabaci (hemiptera: aleyrodidae) meam1 cryptic species.use of plant secondary metabolic compounds is an important method for insect pest control. in this study, the survival, development, and reproduction of bemisia tabaci (gennadius) (hemiptera: aleyrodidae) meam1 cryptic species were compared over two consecutive generations on three cotton cultivars of different gossypol levels. both cotton cultivar and generation significantly affected the fitness of the whitefly. in both generations, the immature development times on the low-gossypol cultivar z ...201323865205
population genetics of invasive bemisia tabaci (hemiptera: aleyrodidae) cryptic species in the united states based on microsatellite markers.the bemisia tabaci (gennadius) (hemiptera: aleyrodidae) cryptic species complex of whiteflies contains two species, meam1 and med, that are highly invasive in supportive climates the world over. in the united states, meam1 occurs both in the field and in the greenhouse, but med is only found in the greenhouse. to make inferences about the population structure of both species, and the origin and recent spread of med within the united states, 987 meam1 whiteflies and 340 med whiteflies were genoty ...201323865202
relative influence of plant quality and natural enemies on the seasonal dynamics of bemisia tabaci (hemiptera: aleyrodidae) in cotton.the abundance and distribution of insect herbivores is determined by, among other things, plant quality and natural enemies. these two factors vary temporally and spatially, subsequently affecting seasonal population dynamics. the relative influence of plant quality and natural enemies on the seasonal dynamics of bemisia tabaci (gennadius) was investigated in a 3-yr field study in cotton. plant quality was manipulated through varying irrigation regimes: irrigations done at 20, 40, and 60% soil w ...201323865191
spatiotemporal patterns of induced resistance and susceptibility linking diverse plant parasites.induced defenses mediate interactions between parasites sharing the same host plant, but the outcomes of these interactions are challenging to predict because of spatiotemporal variation in plant responses and differences in defense pathways elicited by herbivores or pathogens. dissecting these mediating factors necessitates an approach that encompasses a diversity of parasitic feeding styles and tracks interactions over space and time. we tested indirect plant-mediated relationships across thre ...201323851986
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