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population genetic structure of diaphorina citri kuwayama (hemiptera: liviidae): host-driven genetic differentiation in china.the asian citrus psyllid diaphorina citri kuwayama is a major pest in citrus production, transmitting candidatus liberibacter asiaticus. it has spread widely across eastern and southern china. unfortunately, little is known about the genetic diversity and population structure of d. citri, making pest control difficult. in this study, nine specifically developed ssr markers and three known mitochondrial dna were used for population genetics study of d. citri using 225 samples collected from all 7 ...201829367741
modeling the phenology of asian citrus psyllid (hemiptera: liviidae) in urban southern california: effects of environment, habitat, and natural enemies.modeling can be used to characterize the effects of environmental drivers and biotic factors on the phenology of arthropod pests. from a biological control perspective, population dynamics models may provide insights as to when the most vulnerable pest life stages are available for natural enemies to attack. analyses presented here used temperature and habitat dependent, instar-specific, discrete models to investigate the population dynamics of asian citrus psyllid, diaphorina citri kuwayama (he ...201829373671
putative sex pheromone of the asian citrus psyllid, diaphorina citri, breaks down into an attractant.under laboratory conditions, mating activity in asian citrus psyllid (acp) started 4 days after emergence, peaked at day 7, and showed a clear window of activity starting 8 h into the photophase and extending through the first hour of the scotophase. we confirmed that acp males are attracted to emanations from conspecific females. traps loaded with a candidate compound enriched with female extract, lignoceryl acetate (24ac), at various doses were active only after being deployed for several week ...201829323263
global mtdna genetic structure and hypothesized invasion history of a major pest of citrus, diaphorina citri (hemiptera: liviidae).the asian citrus psyllid diaphorina citri kuwayama is a key pest of citrus as the vector of the bacterium causing the "huanglongbing" disease (hlb). to assess the global mtdna population genetic structure, and possible dispersal history of the pest, we investigated genetic variation at the coi gene collating newly collected samples with all previously published data. our dataset consists of 356 colonies from 106 geographic sites worldwide. high haplotype diversity (h-mean = 0.702 ± 0.017), low n ...201829321868
diaphorina citri nymphs are resistant to morphological changes induced by "candidatus liberibacter asiaticus" in midgut epithelial cells."candidatus liberibacter asiaticus" is the causative bacterium associated with citrus greening disease. "ca. l. asiaticus" is transmitted by diaphorina citri more efficiently when it is acquired by nymphs rather than adults. why this occurs is not known. we compared midguts of d. citri reared on healthy or "ca. l. asiaticus"-infected citrus trees using quantitative pcr, confocal microscopy, and mitochondrial superoxide staining for evidence of oxidative stress. consistent with its classification ...201829311247
metabolic alterations in the nymphal instars of diaphorina citri induced by candidatus liberibacter asiaticus, the putative pathogen of huanglongbing.currently, huanglongbing is the most damaging disease of citrus causing huge economic losses. the disease is caused by the gram-negative bacterium candidatus liberibacter asiaticus (clas). the pathogen is transmitted in a persistent propagative circulative manner within its vector, the asian citrus psyllid, diaphorina citri. exploring the metabolic alteration in the vector may lead to a better understanding of the nutritional needs of clas and to designing an artificial medium for culturing the ...201829370262
citrus flush shoot ontogeny modulates biotic potential of diaphorina citri.the biology and behaviour of the psyllid diaphorina citri kuwayama (hemiptera: sternorrhyncha: liviidae), the major insect vector of bacteria associated with huanglongbing, have been extensively studied with respect to host preferences, thermal requirements, and responses to visual and chemical volatile stimuli. however, development of the psyllid in relation to the ontogeny of immature citrus flush growth has not been clearly defined or illustrated. such information is important for determining ...201829304052
insecticide resistance of adults and nymphs of asian citrus psyllid populations from apatzingán valley, mexico.control of the asian citrus psyllid diaphorina citri kuwayama, the most important pest of citrus worldwide, is based on the use of insecticides, though unsatisfactory results have recently been reported. in this study, insecticide resistance of d. citri to three insecticides (bifenthrin, malathion, and chlorpyrifos) was examined.201828719016
β-caryophyllene emitted from a transgenic arabidopsis or chemical dispenser repels diaphorina citri, vector of candidatus liberibacters.production of citrus, the main fruit tree crop worldwide, is severely threatened by huanglongbing (hlb), for which as yet a cure is not available. spread of this bacterial disease in america and asia is intimately connected with dispersal and feeding of the insect vector diaphorina citri, oligophagous on rutaceous host plants. effective control of this psyllid is an important component in successful hlb management programs. volatiles released from the non-host guava have been shown to be repelle ...201728717202
the candidatus liberibacter-host interface: insights into pathogenesis mechanisms and disease control."candidatus liberibacter" species are associated with economically devastating diseases of citrus, potato, and many other crops. the importance of these diseases as well as the proliferation of new diseases on a wider host range is likely to increase as the insects vectoring the "ca. liberibacter" species expand their territories worldwide. here, we review the progress on understanding pathogenesis mechanisms of "ca. liberibacter" species and the control approaches for diseases they cause. we di ...201728637377
genetic variation and potential co-infection of wolbachia among widespread asian citrus psyllid (diaphorina citri kuwayama) populations.wolbachia can profoundly influence the survival, reproduction, and defenses of insect hosts. these interactions could potentially be harnessed for managing pests or insect-transmitted diseases. diaphorina citri kuwayama is a phloem-feeding pest capable of transmitting the putative causal agent of citrus greening, candidatus liberibacter asiaticus (clas). like many insects, d. citri is also infected with wolbachia (wdi). recent studies indicate that the relative abundance of wdi could be associat ...201729286204
contrasting amino acid profiles among permissive and non-permissive hosts of candidatus liberibacter asiaticus, putative causal agent of huanglongbing.huanglongbing is a devastating disease of citrus. in this study, a comprehensive profile of phloem sap amino acids (aa) in four permissive host plants of candidatus liberibacter asiaticus (clas) and three non-permissive rutaceae plants was conducted to gain a better understanding of host factors that may promote or suppress the bacterium. the aa profiles of diaphorina citri nymphs and adults were similarly analyzed. a total of 38 unique aas were detected in phloem sap of the various plants and d ...201729236706
acute toxicity of fresh and aged residues of pesticides to the parasitoid tamarixia radiata and to the hlb-bacteria vector diaphorina citri.one method for controlling the asian citrus psyllid (acp) diaphorina citri kuwayama, the vector of the putative causal agent of huanglongbing, uses the parasitoid tamarixia radiata (waterston). however, the general intensive use of insecticides has reduced the numbers of this parasitoid. this study evaluated the effect of the residual action of 24 insecticides on t. radiata and also determined the differential toxicity of insecticides to d. citri and t. radiata, using three bioassays. in the fir ...201729222706
'candidatus liberibacter asiaticus' accumulates inside endoplasmic reticulum associated vacuoles in the gut cells of diaphorina citri.citrus greening disease known also as huanglongbing (hlb) caused by the phloem-limited bacterium 'candidatus liberibacter asiaticus' (clas) has resulted in tremendous losses and the death of millions of trees worldwide. clas is transmitted by the asian citrus psyllid diaphorina citri. the closely-related bacteria 'candidatus liberibacter solanacearum' (clso), associated with vegetative disorders in carrots, is transmitted by the carrot psyllid bactericera trigonica. a promising approach to preve ...201729208900
rna interference of acetylcholinesterase in the asian citrus psyllid, diaphorina citri, increases its susceptibility to carbamate and organophosphate insecticides.the asian citrus psyllid, diaphorina citri kuwayama (hemiptera: lividae) transmits the candidatus liberibacter asiaticus, which causes citrus greening disease or huanglongbing, (hlb). to date, there is no efficient cure for hlb disease and the control of d. citri using insecticides became the most important tools for the management of hlb. however, the extensive use of insecticides could increase d. citri resistance to these insecticides. the objective of this study was to investigate the effect ...201729183615
wavelength and polarization affect phototaxis of the asian citrus psyllid.the asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae), is a primary pest of citrus due to its status as a vector of the citrus disease, huanglongbing. we evaluated the effects of light of specific wavelength and polarization on phototactic behavior of d. citri using a horizontal bioassay arena. wavelength-associated positive phototaxis was associated with short wavelength uv (350-405 nm) targets whereas little or no responses were seen in longer wavelength targets in the visi ...201728825636
compatibility and efficacy of isaria fumosorosea with horticultural oils for mitigation of the asian citrus psyllid, diaphorina citri (hemiptera: liviidae).horticultural oils are an important component of integrated management programs of several phytophagous arthropods and pathogens affecting fruit, ornamentals and vegetables in greenhouse and field production systems. although effective against the target pest, their incompatibility with biological control agents can compromise efforts to develop eco-friendly management programs for important agricultural pests. in this study, we assessed the in vitro effect of selected refined petroleum oils use ...201729088086
rna interference of two glutathione s-transferase genes, diaphorina citri dcgste2 and dcgstd1, increases the susceptibility of asian citrus psyllid (hemiptera: liviidae) to the pesticides fenpropathrin and thiamethoxam.the asian citrus psyllid, diaphorina citri kuwayama, is an important agricultural pest of citrus globally. foliar application of chemical insecticides is the most widely used option for reducing d. citri populations. knockdown of glutathione s-transferase (gst) in several insect species leads to increased susceptibility to insecticides; however, information about the detoxifying role of gst genes in d. citri is unavailable.201728971568
behavior of bacteriome symbionts during transovarial transmission and development of the asian citrus psyllid.the asian citrus psyllid diaphorina citri kuwayama (hemiptera: liviidae) is a serious pest worldwide, transmitting candidatus liberibacter spp. (alphaproteobacteria), the causative agents of a devastating citrus disease known as huanglongbing or greening disease. in a symbiotic organ called the bacteriome, d. citri possesses an organelle-like defensive symbiont, candidatus profftella armatura (betaproteobacteria), and a nutritional symbiont, ca. carsonella ruddii (gammaproteobacteria). drastical ...201729240843
evidence of behavior-based utilization by the asian citrus psyllid of a combination of uv and green or yellow wavelengths.the asian citrus psyllid, diaphorina citri, vectors huanglongbing (hlb), the most serious disease affecting citrus globally. d. citri and hlb have spread to the major citrus growing regions of north america causing billions of dollars of damage in florida alone. the visual behavior of d. citri is not well characterized and more knowledge is needed to improve attractive traps for monitoring and control of the d. citri. bioassays were conducted to evaluate attraction to light transmitted through d ...201729236740
delivery of dsrna through topical feeding for rna interference in the citrus sap piercing-sucking hemipteran, diaphorina citri.rna interference (rnai) is a powerful means to study functional genomics in insects. the delivery of dsrna is a challenging step in the development of rnai assay. here, we describe a new delivery method to increase the effectiveness of rnai in the asian citrus psyllid diaphorina citri. bromophenol blue droplets were topically applied to fifth instar nymphs and adults on the ventral side of the thorax between the three pairs of legs. in addition to video recordings that showed sucking of the brom ...201728585706
an assessment of interspecific competition between two introduced parasitoids of diaphorina citri (hemiptera: liviidae) on caged citrus plants.two parasitoids attacking nymphs of asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae), tamarixia radiata (waterston) (hymenoptera: eulophidae) and diaphorencyrtus aligarhensis (shafee, alam & agarwal) (hymenoptera: encyrtidae) are being released in california, usa in a classical biological control program. to evaluate the effect of multiple parasitoid species on d. citri mortality, we conducted mesocosm experiments under controlled conditions using a complete block design wit ...201728590080
sperm morphology of the leafhopper diaphorina citri kuwayama (hemiptera: sternorrhyncha: psylloidea: liviidae).in this study, by using light and electron microscopy, we describe the sperm morphology of the leafhopper diaphorina citri, a serious pest of citrus throughout the world. in this species the sperm measures 538.49±8.75μm in length, and as observed in psylloids, the sperm, when manipulated, opens into two filaments, one of which is attached to the nuclear base and the other becomes free. along the flagellum, and only of it, there are lateral projections, about 2μm in length. furthermore, at the en ...201728431332
economic injury levels for asian citrus psyllid control in process oranges from mature trees with high incidence of huanglongbing.the asian citrus psyllid (acp), diaphorina citri kuwayama, is the key pest of citrus wherever it occurs due to its role as vector of huanglongbing (hlb) also known as citrus greening disease. insecticidal vector control is considered to be the primary strategy for hlb management and is typically intense owing to the severity of this disease. while this approach slows spread and also decreases severity of hlb once the disease is established, economic viability of increasingly frequent sprays is u ...201728426676
tale of the huanglongbing disease pyramid in the context of the citrus microbiome.the huanglongbing (hlb) disease pyramid is composed of liberibacters, psyllid vectors, citrus hosts, and the environment. the epidemiological outcomes for liberibacter-associated plant diseases are collectively determined by the inherent relationships among plant-liberibacters-psyllids, and how various environmental factors affect plant-liberibacter-psyllid interactions. citrus-liberibacter-psyllid interactions occur in a complex microbiome system. in this review, we focus on the progress in und ...201728095208
ldtr is a master regulator of gene expression in liberibacter asiaticus.huanglongbing or citrus greening disease is causing devastation to the citrus industry. liberibacter asiaticus, an obligate intracellular pathogen of citrus, is one the causative agents of the disease. most of the knowledge about this bacterium has been deduced from the in silico exploration of its genomic sequence. l. asiaticus differentially expresses genes during its transmission from the psyllid vector, diaphorina citri, to the plant. however, the regulatory mechanisms for the adaptation of ...201728503858
draft whole-genome sequence of "candidatus liberibacter asiaticus" strain tx2351 isolated from asian citrus psyllids in texas, usa.we report here the draft genome sequence of "candidatus liberibacter asiaticus" strain tx2351, collected from asian citrus psyllids in south texas, usa. the tx2351 genome has a size of 1,252,043 bp, a g+c content of 36.5%, 1,184 predicted open reading frames, and 52 rna genes.201728408682
selection of reference genes for expression studies in diaphorina citri (hemiptera: liviidae).the asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae), is considered the main vector of the bacteria associated with huanglongbing, a very serious disease that has threatened the world citrus industry. the absence of efficient control management protocols, including a lack of resistant cultivars, has led to the development of different approaches to study this pathosystem. the production of resistant genotypes relies on d. citri gene expression analyses by rt-qpcr to assess c ...201729029285
metabolomic response to huanglongbing: role of carboxylic compounds in citrus sinensis response to 'candidatus liberibacter asiaticus' and its vector, diaphorina citri.huanglongbing, a destructive disease of citrus, is caused by the fastidious bacterium 'candidatus liberibacter asiaticus' and transmitted by asian citrus psyllid, diaphorina citri. the impact of 'ca. l. asiaticus' infection or d. citri infestation on valencia sweet orange (citrus sinensis) leaf metabolites was investigated using gas chromatography mass spectrometry, followed by gene expression analysis for 37 genes involved in jasmonic acid (ja), salicylic acid (sa), and proline-glutamine pathwa ...201728510485
a small wolbachia protein directly represses phage lytic cycle genes in "candidatus liberibacter asiaticus" within psyllids.huanglongbing (hlb) is a severe disease of citrus caused by an uncultured alphaproteobacterium "candidatus liberibacter asiaticus" and transmitted by asian citrus psyllids (diaphorina citri). two prophage genomes, sc1 and sc2, integrated in "ca. liberibacter asiaticus" strain uf506 were described previously, and very similar prophages are found resident in the majority of "ca. liberibacter asiaticus" strains described worldwide. the sc1 lytic cycle is marked by upregulation of prophage late gene ...201728608866
effects of different temperature regimes on survival of diaphorina citri and its endosymbiotic bacterial communities.the asian citrus psyllid, diaphorina citri, is a major pest of citrus and vector of citrus greening (huanglongbing) in asian. in our field-collected psyllid samples, we discovered that fuzhou (china) and faisalabad (pakistan), populations harbored an obligate primary endosymbiont candidatus carsonella (gen. nov.) with a single species, candidatus carsonella ruddii (sp. nov.) and a secondary endosymbiont, wolbachia surface proteins (wsp) which are intracellular endosymbionts residing in the bacte ...201728618183
analyses of mitogenome sequences revealed that asian citrus psyllids (diaphorina citri) from california were related to those from florida.asian citrus psyllid (acp, diaphorina citri kuwayama) transmits "candidatus liberibacter asiaticus" (clas), an unculturable alpha-proteobacterium associated with citrus huanglongbing (hlb). clas has recently been found in california. understanding acp population diversity is necessary for hlb regulatory practices aimed at reducing clas spread. in this study, two circular acp mitogenome sequences from california (mt-capsy, ~15,027 bp) and florida (mt-flpsy, ~15,012 bp), usa, were acquired. each m ...201728860662
combining 'omics and microscopy to visualize interactions between the asian citrus psyllid vector and the huanglongbing pathogen candidatus liberibacter asiaticus in the insect gut.huanglongbing, or citrus greening disease, is an economically devastating bacterial disease of citrus. it is associated with infection by the gram-negative bacterium candidatus liberibacter asiaticus (clas). clas is transmitted by diaphorina citri, the asian citrus psyllid (acp). for insect transmission to occur, clas must be ingested during feeding on infected phloem sap and cross the gut barrier to gain entry into the insect vector. to investigate the effects of clas exposure at the gut-pathog ...201728632769
induced preference improves offspring fitness in a phytopathogen vector.in the asian citrus psyllid (diaphorina citri kuwayama), learning facilitates host recognition and mate preference; however, it is unclear whether induced female oviposition preference occurs in this species. we investigated the influence of natal host experience on adult oviposition preference when reared on either 'valencia' orange (citrus x sinesis) or orange jasmine (murraya paniculata). psyllids reared on 'valencia' orange preferred 'valencia' orange as an oviposition host compared with ora ...201728961753
neonicotinoid-induced mortality of diaphorina citri (hemiptera: liviidae) is affected by route of exposure.the use of neonicotinoids in citrus (rutaceae) has increased substantially to help manage the asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae), a vector of the devastating citrus disease, huanglongbing (hlb). in citrus pest management programs, neonicotinoids are most often applied to the soil as a drench and move through xylem channels from the roots into the foliage. we developed a novel assay to quantify the dose required to kill d. citri following ingestion and compare i ...201728961723
concomitant loss of the glyoxalase system and glycolysis makes the uncultured pathogen "candidatus liberibacter asiaticus" an energy scavenger.methylglyoxal (mg) is a cytotoxic, non-enzymatic byproduct of glycolysis that readily glycates proteins and dna, resulting in carbonyl stress. glyoxalase i and ii (gloa and glob) sequentially convert mg into d-lactic acid using glutathione (gsh) as a cofactor. the glyoxalase system is essential for the mitigation of mg-induced carbonyl stress, preventing subsequent cell death, and recycling gsh for maintenance of cellular redox poise. all pathogenic liberibacters identified to date are unculture ...201728939611
resistance management for asian citrus psyllid, diaphorina citri kuwayama, in florida.the asian citrus psyllid, diaphorina citri kuwayma, is one of the most important pests in citrus production. the objective of this study was to evaluate d. citri resistance management with three insecticide rotations and compare them with no rotation and an untreated check. the different insecticides (modes of action) tested were: dimethoate, imidacloprid, diflubenzuron, abamectin 3% + thiamethoxam 13.9%, and fenpropathrin. eggs, nymph, and adult psyllids were counted weekly. five insecticide ap ...201728930170
imidacloprid transport and sorption nonequilibrium in single and multilayered columns of immokalee fine sand.imidacloprid (imd) is a neonicotinoid pesticide soil-drenched to many crops to control piercing-sucking insects such as the asian citrus psyllid (acp). neonicotinoids are persistent in the environment and transport analyses are helpful estimate leaching potential from soils that could result in groundwater pollution. the objective of this study was to analyze imd breakthrough under saturated water flow in soil columns packed with three horizons (a, e, bh) of immokalee fine sand (ifs). also, we u ...201728837702
dynamics of huanglongbing-associated bacterium candidatus liberibacter asiaticus in citrus aurantifolia swingle (mexican lime).the bacterial disease citrus huanglongbing (hlb), associated with "candidatus liberibacter asiaticus" (c.las) has severely impacted the citrus industry, causing a significant reduction in production and fruit quality. in the present study, it was monitored the c.las population dynamics in symptomatic, hlb-positive mexican lime trees (citrus aurantifolia swingle) in a tropical, citrus-producing area of mexico. the objective of this study was to identify the dynamics of the population of huanglong ...201729023002
innate immune system capabilities of the asian citrus psyllid, diaphorina citri.citrus production worldwide is currently threatened by huanglongbing, or citrus greening disease. the associated pathogen, candidatus liberibacter asiaticus (clas), is transmitted by the asian citrus psyllid, diaphorina citri. annotation of the d. citri genome revealed a reduced innate immune system lacking a number of antimicrobial peptides and the imd pathway associated with defense against gram-negative bacteria. we characterized this apparent immune reduction in survival assays in which d. c ...201728624621
susceptibility of diaphorina citri (hemiptera: liviidae) and its parasitoid tamarixia radiata (hymenoptera: eulophidae) to entomopathogenic fungi under laboratory conditions.diaphorina citri (kuwayama) is a global pest of citrus that transmits the bacteria associated with the disease, huanglongbing. entomopathogenic fungi and the parasitoid tamarixia radiata (waterston) are important biological control agents of this pest and likely to interact in d. citri populations. as a basis for interaction studies, we determined the susceptibility of nymphs and adults of d. citri and adults of the parasitoid t. radiata to six fungal isolates from the species beauveria bassiana ...201728721609
functional characterization of lotp from liberibacter asiaticus.liberibacter asiaticus is an unculturable parasitic bacterium of the alphaproteobacteria group hosted by both citrus plants and a psyllid insect vector (diaphorina citri). in the citrus tree, the bacteria thrive only inside the phloem, causing a systemically incurable and deadly plant disease named citrus greening or huanglongbing. currently, all commercial citrus cultivars in production are susceptible to l. asiaticus, representing a serious threat to the citrus industry worldwide. the technica ...201728378385
costs and benefits of insecticide and foliar nutrient applications to huanglongbing-infected citrus trees.the asian citrus psyllid (acp), diaphorina citri kuwayama (hemiptera: psyllidae), vectors candidatus liberibacter asiaticus, which causes huanglongbing (hlb). in florida, hlb incidence is approaching 100% statewide. yields have decreased and production costs have increased since 2005. despite this, some growers are maintaining a level of production and attribute this in part to aggressive psyllid control and foliar nutrition sprays. however, the value of these practices is debated. a replicated ...201727427170
risk assessment of various insecticides used for management of asian citrus psyllid, diaphorina citri in florida citrus, against honey bee, apis mellifera.the asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae), is a major pest of citrus trees worldwide. a wide variety of insecticides are used to manage d. citri populations within citrus groves in florida. however, in areas shared by citrus growers and beekeepers the use of insecticides may increase the risks of apis mellifera  l. (hymenoptera: apidae) loss and contaminated honey. the objective of this research was to determine the environmental toxicity of insecticides, spanning ...201728116643
one target, two mechanisms: the impact of candidatus liberibacter asiaticus and its vector, diaphorina citri on citrus leaf pigments.huanglongbing is currently the largest threat to global citrus production. we examined the effect of hlb pathogen, candidatus liberibacter asiaticus-infection and/or its vector, diaphorina citri-infestation on valencia sweet orange leaf pigments using hplc, followed by gene expression analysis for 46 involved genes in carotenoids- and chlorophylls-biosynthesis pathways. both clas and d. citri alter the total citrus leaf pigments balance with a greater impact by clas. while zeaxanthin was accumul ...201728358623
protein interaction networks at the host-microbe interface in diaphorina citri, the insect vector of the citrus greening pathogen.the asian citrus psyllid (diaphorina citri) is the insect vector responsible for the worldwide spread of 'candidatus liberibacter asiaticus' (clas), the bacterial pathogen associated with citrus greening disease. developmental changes in the insect vector impact pathogen transmission, such that d. citri transmission of clas is more efficient when bacteria are acquired by nymphs when compared with adults. we hypothesize that expression changes in the d. citri immune system and commensal microbiot ...201728386418
genetic diversity of diaphorina citri and its endosymbionts across east and southeast asia.diaphorina citri is the vector of 'candidatus liberibacter asiaticus', the most widespread pathogen associated huanglongbing, the most serious disease of citrus. to enhance our understanding of the distribution and origin of the psyllid, we investigated the genetic diversity and population structures of 24 populations in asia and one from florida based on the mtcoi gene. simultaneously, genetic diversity and population structures of the primary endosymbiont (p-endosymbiont) 'candidatus carsonell ...201728374537
rna interference of carboxyesterases causes nymph mortality in the asian citrus psyllid, diaphorina citri.asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae), is an important pest of citrus. in addition, d. citri is the vector of huanglongbing, a destructive disease in citrus, also known as citrus greening disease caused by candidatus liberibacter asiaticus. huanglongbing causes huge losses for citrus industries. insecticide application for d. citri is the major strategy to prevent disease spread. the heavy use of insecticides causes development of insecticide resistance. we used r ...201728195667
spatiotemporal dynamics of the southern california asian citrus psyllid (diaphorina citri) invasion.biological invasions are governed by spatial processes that tend to be distributed in non-random ways across landscapes. characterizing the spatial and temporal heterogeneities of the introduction, establishment, and spread of non-native insect species is a key aspect of effectively managing their geographic expansion. the asian citrus psyllid (diaphorina citri), a vector of the bacterium associated with huanglongbing (hlb), poses a serious threat to commercial and residential citrus trees. in 2 ...201728278188
influence of abiotic factors on flight initiation by asian citrus psyllid (hemiptera: liviidae).predicting the emergence and arrival of insect pests is paramount for integrated pest management. to achieve this goal, it is important to understand how abiotic factors influence pest dispersal behavior. we investigated the effects of abiotic conditions on flight initiation by the asian citrus psyllid, diaphorina citri kuwayama. we first explored the effect of barometric pressure changes on flight initiation. we used a custom-made barometric chamber and observed the activity of d. citri as meas ...201728334135
oral delivery of double-stranded rnas induces mortality in nymphs and adults of the asian citrus psyllid, diaphorina citri.the asian citrus psyllid (acp), diaphorina citri kuwayama, is one of the most important citrus pests. acp is the vector of the phloem-limited bacteria candidatus liberibacter americanus and candidatus liberibacter asiaticus, the causal agents of the devastating citrus disease huanglongbing (hlb). the management of hlb is based on the use of healthy young plants, eradication of infected plants and chemical control of the vector. rna interference (rnai) has proven to be a promising tool to control ...201728282380
sclerenchymatous ring as a barrier to phloem feeding by asian citrus psyllid: evidence from electrical penetration graph and visualization of stylet pathways.asian citrus psyllid (diaphorina citri) feeding behaviors play a significant role in the transmission of the phloem-limited candidatus liberibacter asiaticus (clas) bacterium that causes the economically devastating citrus greening disease. sustained phloem ingestion by d. citri on clas infected plants is required for pathogen acquisition and transmission. recent studies have shown a fibrous ring of thick-walled sclerenchyma around the phloem in mature, fully expanded citrus leaves that is more ...201728278248
a plant bacterial pathogen manipulates its insect vector's energy metabolism.insect-transmitted plant-pathogenic bacteria may alter their vectors' fitness, survival, behavior, and metabolism. because these pathogens interact with their vectors on the cellular and organismal levels, potential changes at the biochemical level might occur. "candidatus liberibacter asiaticus" (clas) is transmitted in a persistent, circulative, and propagative manner. the genome of clas revealed the presence of an atp translocase that mediates the uptake of atp and other nucleotides from medi ...201728039132
double-stranded rna delivery through soaking mediates silencing of the muscle protein 20 and increases mortality to the asian citrus psyllid, diaphorina citri.asian citrus psyllid, diaphorina citri kuwayama, is the most important economic pest of citrus because it transmits candidatus liberibacter asiaticus (clas), the causal agent of huanglongbing (hlb). silencing genes by rna interference (rnai) is a promising approach for controlling d. citri. rnai-based insect management strategies depend on the selection of suitable target genes.201728195429
effects of temperature, photoperiod, and rainfall on morphometric variation of diaphorina citri (hemiptera: liviidae).phenotypic plasticity provides a mechanism by which an organism can adapt to new or changing environments. earlier studies have demonstrated the variability of diaphorina citri kuwayama (asian citrus psyllid) population dynamics, but no analysis of morphological changes induced by seasonal or artificial laboratory-induced conditions has yet been documented. such morphometric variation has been found to correspond in dispersal capabilities in several insect taxa. in this study, the effects of tem ...201728031429
comparative proteomic analysis of hemolymph from uninfected and candidatus liberibacter asiaticus-infected diaphorina citri.hemolymph was characterized from diaphorina citri adults infected with the phytopathogen, candidatus liberibacter asiaticus (clas), and compared with that from uninfected psyllids. this study identified 5531 and 3220 peptides within infected and uninfected hemolymph using nano-lc-ms/ms. a reduced number of proteins were detected for d. citri and all known endosymbionts within infected hemolymph as compared to uninfected hemolymph. a large number of immune defense proteins were absent from d. cit ...201727990558
latency and persistence of 'candidatus liberibacter asiaticus' in its psyllid vector, diaphorina citri (hemiptera: liviidae).although 'candidatus liberibacter asiaticus' (las) is a major pathogen associated with citrus huanglongbing (hlb), some characteristics of transmission by the psyllid vector diaphorina citri are not fully understood. we examined the latent period and persistence of transmission of las by d. citri in a series of experiments at 25°c, in which third-instar psyllid nymphs and 1-week-old adults were confined on infected citrus for an acquisition access period (aap), and submitted to sequential inocul ...201727841960
evaluation of systemic neonicotinoid insecticides for the management of the asian citrus psyllid diaphorina citri on containerized citrus.studies were conducted to evaluate uptake and retention of three systemic neonicotinoid insecticides, dinotefuran, imidacloprid and thiamethoxam, in potted citrus nursery plants treated at standard label rates. infestation of these plants placed at a field site with moderate levels of asian citrus psyllid (acp) was monitored for 14 weeks following treatments, and insecticide residues in leaf tissue were quantified using enzyme-linked immunosorbent assay (elisa). bioassays were conducted using le ...201727714916
male psyllids differentially learn in the context of copulation.in the asian citrus psyllid, diaphorina citri kuwayama, stimulatory cuticular hydrocarbons act as sex pheromone attractants. male psyllids locate aggregations of females using those olfactory cues, as well as vibrational communication on the plant surface. although previous research has indicated that learning plays a role in modulating female reproductive behaviors in psyllids, it is unknown whether males similarly use learning to increase the likelihood of copulatory success. we used an olfact ...201728178203
characterization of the voltage-gated sodium channel of the asian citrus psyllid, diaphorina citri.the asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae), is an important insect pest of citrus. it is the vector of 'candidatus' liberibacter asiaticus, a phloem-limited bacterium that infects citrus, resulting in the disease huanglongbing (hlb). disease management relies heavily on suppression of d. citri populations with insecticides, including pyrethroids. in recent annual surveys to monitor insecticide resistance, reduced susceptibility to fenpropathrin was identified in se ...201726537022
disrupting mating behavior of diaphorina citri (liviidae).severe economic damage from citrus greening disease, caused by 'candidatus liberibacter asiaticus' bacteria, has stimulated development of methods to reduce mating and reproduction in populations of its insect vector, diaphorina citri (hemiptera: liviidae). male d. citri find mating partners by walking on host plants, intermittently producing vibrational calls that stimulate duetting replies by receptive females. the replies provide orientational feedback, assisting the search process. to test a ...201627707945
impact of different temperatures on survival and energy metabolism in the asian citrus psyllid, diaphorina citri kuwayama.temperature influences the life history and metabolic parameters of insects. asian citrus psyllid (acp), diaphorina citri is a tropical and subtropical pest. acp invaded new regions around the world and threatened the citrus industry as a vector for huanglongbing (hlb) disease. acp is widely distributed and can survive high (up to 45 °c) and low temperatures (as low as -6 °c). the precise mechanism of temperature tolerance in acp is poorly understood. we investigated adult survival, cellular ene ...201626603556
enhanced acquisition rates of 'candidatus liberibacter asiaticus' by the asian citrus psyllid (hemiptera: liviidae) in the presence of vegetative flush growth in citrus.the asian citrus psyllid preferentially feeds and exclusively reproduces on young, newly emerged flush shoots of citrus. asian citrus psyllid nymphs feed and complete their life stages on these flush shoots. recent studies conducted under greenhouse conditions have shown that the transmission rates of 'candidatus liberibacter asiaticus' (clas), the putative causal agent of huanglongbing disease of citrus, are enhanced when flush shoots are present. however, it is unclear if clas acquisition by m ...201627451998
diaphorina citri induces huanglongbing-infected citrus plant volatiles to repel and reduce the performance of propylaea japonica.transmission of plant pathogens through insect vectors is a complex biological process involving interactions between the host plants, insects, and pathogens. simultaneous impact of the insect damage and pathogenic bacteria in infected host plants induce volatiles that modify not only the behavior of its insect vector but also of their natural enemies, such as parasitoid wasps. therefore, it is essential to understand how insects such as the predator ladybird beetle responds to volatiles emitted ...201628083006
effects of candidatus liberibacter asiaticus on the fitness of the vector diaphorina citri.the asian citrus psyllid (acp), diaphorina citri kuwayama transmits the bacterium 'candidatus liberibacter asiaticus' (las), which causes citrus huanglongbing (hlb) disease. although many studies have been conducted on the biology of acp on different host plants, few have taken the plant, las bacteria and the vector insect within one context to evaluate the effects of las on the fitness of acp under field conditions. understanding the relationship between las and acp is critical for both acp and ...201627667799
monitoring for insecticide resistance in asian citrus psyllid (hemiptera: psyllidae) populations in florida.the development of insecticide resistance in asian citrus psyllid, diaphorina citri kuwayama, populations is a serious threat to the citrus industry. as a contribution to a resistance management strategy, we developed a glass vial technique to monitor field populations of asian citrus psyllid for insecticide resistance. diagnostic concentrations needed to separate susceptible genotypes from resistant individuals were determined for cypermethrin (0.5 μg per vial), malathion (1.0 μg per vial), dia ...201626709293
imidacloprid extraction from citrus leaves and analysis by liquid chromatography-mass spectrometry (hplc-ms/ms).a procedure was developed to extract imidacloprid (imd) from newly-flushed and fully-expanded citrus leaves. the extraction was conducted in a bullet blender, using a small sample mass (0.5 g of fresh tissue), stainless-steel beads (24 g), and methanol as extractant (10 ml). the extracts did not require further clean-up before analysis by hplc-ms/ms. the method was validated with control samples from imd-untreated hamlin orange trees. the method limit of detection and limit of quantitation were ...201626988226
phenology of asian citrus psyllid (hemiptera: liviidae), with special reference to biological control by tamarixia radiata, in the residential landscape of southern california.since its discovery in 2008, the pestiferous asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae), has become widely established in residential citrus trees throughout southern california. in 2011, tamarixia radiata (waterston) (hymenoptera: eulophidae), a host-specific parasitoid of d. citri, sourced from punjab pakistan, was introduced into california as part of a classical biological program aimed at suppressing d. citri populations in urban areas. despite these release effor ...201626957552
inter-population variability of endosymbiont densities in the asian citrus psyllid (diaphorina citri kuwayama).the asian citrus psyllid (diaphorina citri kuwayama) is an insect pest capable of transmitting candidatus liberibacter asiaticus (clas), the causal agent of citrus greening in north america. d. citri also harbors three endosymbionts, wolbachia, candidatus carsonella ruddii, and candidatus profftella armatura, which may influence d. citri physiology and fitness. although genomic researches on these bacteria have been conducted, much remains unclear regarding their ecology and inter-population var ...201626846216
transmission and propagation of 'candidatus liberibacter asiaticus' by grafting with individual citrus leaves.huanglongbing (hlb) is a chronic, progressive decline disease in citrus associated with a systemic infection by the bacterium 'candidatus liberibacter asiaticus'. transmission of the bacterium in the field is by the asian citrus psyllid, diaphorina citri kuwayama. experimental propagation of 'ca. l. asiaticus' is done primarily by grafting pieces of bud wood from an infected plant. to produce a small-scale model system for investigation of pathogen biology, we investigated grafting single leaves ...201626807818
huanglongbing: an overview of a complex pathosystem ravaging the world's citrus.citrus huanglongbing (hlb) has become a major disease and limiting factor of production in citrus areas that have become infected. the destruction to the affected citrus industries has resulted in a tremendous increase to support research that in return has resulted in significant information on both applied and basic knowledge concerning this important disease to the global citrus industry. recent research indicates the relationship between citrus and the causal agent of hlb is shaped by multip ...201626466921
the influence of learning on host plant preference in a significant phytopathogen vector, diaphorina citri.although specialist herbivorous insects are guided by innate responses to host plant cues, host plant preference may be influenced by experience and is not dictated by instinct alone. the effect of learning on host plant preference was examined in the asian citrus psyllid, diaphorina citri; vector of the causal agent of citrus greening disease or huanglongbing. we investigated: a) whether development on specific host plant species influenced host plant preference in mature d. citri; and b) the e ...201626930355
formic and acetic acids in degradation products of plant volatiles elicit olfactory and behavioral responses from an insect vector.volatile phytochemicals play a role in orientation by phytophagous insects. we studied antennal and behavioral responses of the asian citrus psyllid, diaphorina citri, vector of the citrus greening disease pathogen. little or no response to citrus leaf volatiles was detected by electroantennography. glass cartridges prepared with β-ocimene or citral produced no response initially but became stimulatory after several days. both compounds degraded completely in air to a number of smaller molecules ...201626857741
efficacy of essential oil of piper aduncum against nymphs and adults of diaphorina citri.insecticide application is the main way to control diaphorina citri. however, it causes environmental contamination, has a negative impact on beneficial organisms and leads to psyllid resistance. the essential oil of piper aduncum has low toxicity towards the environment and contains dillapiol, which has proven to be effective against several crop pests. here, we studied its efficacy against nymphs and adults of d. citri under laboratory conditions. oils with three concentrations of dillapiol (6 ...201626331551
exposure to guava affects citrus olfactory cues and attractiveness to diaphorina citri (hemiptera: psyllidae).intercropping can reduce agricultural pest incidence, and represents an important sustainable alternative to conventional pest control methods. understanding the ecological mechanisms for intercropping could help optimize its use, particularly in tropical systems which present a large number of intercropping possibilities. citrus is threatened worldwide by greening disease (huanglongbing, hlb) vectored by the asian citrus psyllid, diaphorina citri kuwayama (hemiptera: psyllidae). control of hlb ...201627247354
disruption of vector host preference with plant volatiles may reduce spread of insect-transmitted plant pathogens.plant pathogens can manipulate the odor of their host; the odor of an infected plant is often attractive to the plant pathogen vector. it has been suggested that this odor-mediated manipulation attracts vectors and may contribute to spread of disease; however, this requires further broad demonstration among vector-pathogen systems. in addition, disruption of this indirect chemical communication between the pathogen and the vector has not been attempted. we present a model that demonstrates how a ...201627193763
two-spotted ladybeetle adalia bipunctata l. (coleoptera: coccinellidae): a commercially available predator to control asian citrus psyllid diaphorina citri (hemiptera: liviidae).the asian citrus psyllid diaphorina citri kuwayama (hemiptera: liviidae) is an economically important pest of citrus because it serves as a vector of the causal pathogens of huanglongbing (hlb) also known as citrus greening disease. the increased use of insecticides for control of d. citri negatively impacts several natural enemies including some effective ladybeetle species which are not available commercially. the two-spotted ladybeetle, adalia bipunctata (coleoptera: coccinellidae) is found i ...201627631730
complete genome sequence of the largest known flavi-like virus, diaphorina citri flavi-like virus, a novel virus of the asian citrus psyllid, diaphorina citri.a novel flavi-like virus tentatively named diaphorina citri flavi-like virus (dcflv) was identified in field populations of diaphorina citri through small rna and transcriptome sequencing followed by reverse transcription (rt)-pcr. we report here the complete nucleotide sequence and genome organization of dcflv, the largest flavi-like virus identified to date.201627609921
nucleotides, micro- and macro-nutrients, limonoids, flavonoids, and hydroxycinnamates composition in the phloem sap of sweet orange.currently, the global citrus production is declining due to the spread of huanglongbing (hlb). hlb, otherwise known as citrus greening, is caused by candidatus liberibacter asiaticus (clas) and is transmitted by the asian citrus psyllids (acp), diaphorina citri kuwayama. acp transmits clas bacterium while feeding on the citrus phloem sap. multiplication of clas in the phloem of citrus indicates that the sap contains all the essential nutrients needed for clas. in this study, we investigated the ...201627171979
complete genome sequence of diaphorina citri-associated c virus, a novel putative rna virus of the asian citrus psyllid, diaphorina citri.we present here the complete nucleotide sequence and genome organization of a novel putative rna virus identified in field populations of the asian citrus psyllid, diaphorina citri, through sequencing of the transcriptome followed by reverse transcription-pcr (rt-pcr). we tentatively named this virus diaphorina citri-associated c virus (dcacv). dcacv is an unclassified positive-sense rna virus.201627445370
a review of techniques for detecting huanglongbing (greening) in citrus.huanglongbing (hlb) is the most destructive disease of citrus worldwide. monitoring of health and detection of diseases in trees is critical for sustainable agriculture. hlb symptoms are virtually the same wherever the disease occurs. the disease is caused by candidatus liberibacter spp., vectored by the psyllids diaphorina citri kuwayama and trioza erytreae. electron microscopy was the first technique used for hlb detection. nowadays, scientists are working on the development of new techniques ...201627590666
quality matters: influences of citrus flush physicochemical characteristics on population dynamics of the asian citrus psyllid (hemiptera: liviidae).studies were conducted to relate the influence of the physical characteristics, leaf nutrient content and phloem sap amino acid concentration of citrus flush shoots on the densities of various diaphorina citri life stages. adult d. citri preferentially selected young shoots for feeding and numbers of d. citri immatures were positively correlated with flush shoot softness. young flush shoots had higher concentrations of macro and micro nutrients relative to mature ones and this was associated wit ...201628030637
complete genome sequence of a putative densovirus of the asian citrus psyllid, diaphorina citri.here, we report the complete genome sequence of a putative densovirus of the asian citrus psyllid, diaphorina citri diaphorina citri densovirus (dcdnv) was originally identified through metagenomics, and here, we obtained the complete nucleotide sequence using pcr-based approaches. phylogenetic analysis places dcdnv between viruses of the ambidensovirus and iteradensovirus genera.201627469948
better together: association with 'candidatus liberibacter asiaticus' increases the reproductive fitness of its insect vector, diaphorina citri (hemiptera: liviidae).the duration of the evolutionary association between a pathogen and vector can be inferred based on the strength of their mutualistic interactions. a well-adapted pathogen is likely to confer some benefit or, at a minimum, exhibit low pathogenicity toward its host vector. coevolution of the two toward a mutually beneficial association appears to have occurred between the citrus greening disease pathogen, candidatus liberibacter asiaticus (las), and its insect vector, the asian citrus psyllid, di ...201627418697
essential oil variation from twenty two genotypes of citrus in brazil-chemometric approach and repellency against diaphorina citri kuwayama.the chemical composition of volatile oils from 22 genotypes of citrus and related genera was poorly differentiated, but chemometric techniques have clarified the relationships between the 22 genotypes, and allowed us to understand their resistance to d. citri. the most convincing similarities include the synthesis of (z)-β-ocimene and (e)-caryophyllene for all 11 genotypes of group a. genotypes of group b are not uniformly characterized by essential oil compounds. when stimulated with odor sourc ...201627338332
digital gene expression analysis of ponkan mandarin (citrus reticulata blanco) in response to asia citrus psyllid-vectored huanglongbing infection.citrus huanglongbing (hlb), the most destructive citrus disease, can be transmitted by psyllids and diseased budwoods. although the final symptoms of the two main hlb transmission ways were similar and hard to distinguish, the host responses might be different. in this study, the global gene changes in leaves of ponkan (citrus reticulata) mandarin trees following psyllid-transmission of hlb were analyzed at the early symptomatic stage (13 weeks post inoculation, wpi) and late symptomatic stage ( ...201627384559
transmission rates of ‘ca. liberibacter asiaticus’ by asian citrus psyllid are enhanced by the presence and developmental stage of citrus flush.asian citrus psyllid (diaphorina citri kuwayama) transmits a bacterium ‘candidatus liberibacter asiaticus’ (clas) putatively responsible for a devastating citrus disease known as asiatic huanglongbing (hlb) (citrus greening disease). the psyllid and disease have invaded many citrus-growing regions including the united states, where the disease is seriously jeopardizing the florida citrus industry. we recently concluded research that showed clas transmission rates are increased when citrus flush ...201626884596
thiamethoxam and imidacloprid drench applications on sweet orange nursery trees disrupt the feeding and settling behaviour of diaphorina citri (hemiptera: liviidae).chemical control is the method most used for management of diaphorina citri, the vector of the phloem-limited bacteria associated with citrus huanglongbing (hlb) disease. the objectives of this study were to determine the influence of soil-drench applications of neonicotinoids (thiamethoxam and imidacloprid) on the probing behaviour of d. citri on citrus nursery trees, using the electrical penetration graph (epg) technique, and to measure the d. citri settling behaviour after probing on citrus n ...201626694803
species clarification of isaria isolates used as biocontrol agents against diaphorina citri (hemiptera: liviidae) in mexico.entomopathogenic fungi belonging to the genus isaria (hypocreales: cordycipitaceae) are promising candidates for microbial control of insect pests. currently, the mexican government is developing a biological control program based on extensive application of isaria isolates against diaphorina citri (hemiptera: liviidae), a vector of citrus huanglongbing disease. previous research identified three promising isaria isolates (che-cnrcb 303, 305, and 307; tentatively identified as isaria fumosorosea ...201626895870
oviposition behavior and survival of tamarixia radiata (hymenoptera: eulophidae), an ectoparasitoid of the asian citrus psyllid, diaphorina citri (hemiptera: liviidae), on hosts exposed to an entomopathogenic fungus, isaria fumosorosea (hypocreales: cordycipitaceae), under laboratory conditions.antagonistic interactions between the nymphal parasitoid, tamarixia radiata waterston (hymenoptera: eulophidae), and the arsef 3581 strain of the entomopathogenic fungus, isaria fumosorosea wize (hypocreales: cordycipitaceae), could disrupt biological control of the asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae). three interactions were evaluated under laboratory conditions at 25 °c: 1) parasitoid survival if parasitized hosts were exposed to arsef 3581 blastospores before ...201627435930
acquisition, replication and inoculation of candidatus liberibacter asiaticus following various acquisition periods on huanglongbing-infected citrus by nymphs and adults of the asian citrus psyllid.the asian citrus psyllid, diaphorina citri (hemiptera: liviidae), is the primary vector of candidatus liberibacter asiaticus (las) implicated as causative agent of citrus huanglongbing (citrus greening), currently the most serious citrus disease worldwide. las is transmitted by d. citri in a persistent-circulative manner, but the question of replication of this bacterium in its psyllid vector has not been resolved. thus, we studied the effects of the acquisition access period (aap) by nymphs and ...201627441694
evolutionary conservation of candidate osmoregulation genes in plant phloem sap-feeding insects.the high osmotic pressure generated by sugars in plant phloem sap is reduced in phloem-feeding aphids by sugar transformations and facilitated water flux in the gut. the genes mediating these osmoregulatory functions have been identified and validated empirically in the pea aphid acyrthosiphon pisum: sucrase 1 (suc1), a sucrase in glycoside hydrolase family 13 (gh13), and aquaporin 1 (aqp1), a member of the drosophila integral protein (drip) family of aquaporins. here, we describe molecular anal ...201626896054
laser system for identification, tracking, and control of flying insects.flying insects are common vectors for transmission of pathogens and inflict significant harm to humans and agricultural production in many parts of the world. we present proof of principle for an optical system capable of highly specific vector control. this system utilizes a combination of optical sources, detectors, and sophisticated software to search, detect, and identify flying insects in real-time, with the capability of eradication using a lethal laser pulse. we present data on two insect ...201627410106
metabolomic comparative analysis of the phloem sap of curry leaf tree (bergera koenegii), orange jasmine (murraya paniculata), and valencia sweet orange (citrus sinensis) supports their differential responses to huanglongbing.orange jasmine, murraya paniculata and curry leaf tree, bergera koenegii are alternative hosts for diaphorina citri, the vector of candidatus liberibacter asiaticus (clas), the pathogen of huanglongbing (hlb) in citrus. d. citri feeds on the phloem sap where clas grows. it has been shown that orange jasmine was a better host than curry leaf tree to d. citri. in addition, clas can infect orange jasmine but not curry leaf tree. here, we compared the phloem sap composition of these 2 plants to the ...201627763819
repellent activity of botanical oils against asian citrus psyllid, diaphorina citri (hemiptera: liviidae).the asian citrus psyllid, diaphorina citri kuwayama, is the insect vector of the pathogen causing huanglongbing. we selected three botanical oils to evaluate behavioral activity against d. citri. in laboratory olfactometer assays, fir oil was repellent to d. citri females, while litsea and citronella oils elicited no response from d. citri females. in choice settling experiments, d. citri settled almost completely on control plants rather than on plants treated with fir oil at a 9.5 mg/day relea ...201627429006
asian citrus psyllid rnai pathway - rnai evidence.diaphorina citri, known as the asian citrus psyllid, is an important pest of citrus because it transmits a phloem-limited bacteria strongly implicated in huanglongbing (citrus greening disease). emerging biotechnologies, such as rna interference, could provide a new sustainable and environmentally friendly strategy for the management of this pest. in this study, genome and functional analysis were performed to verify whether the rnai core genes are present in the asian psyllid genome and if the ...201627901078
antennal and abdominal transcriptomes reveal chemosensory genes in the asian citrus psyllid, diaphorina citri.the asian citrus psyllid, diaphorina citri is the principal vector of the highly destructive citrus disease called huanglongbing (hlb) or citrus greening, which is a major threat to citrus cultivation worldwide. more effective pest control strategies against this pest entail the identification of potential chemosensory proteins that could be used in the development of attractants or repellents. however, the molecular basis of olfaction in the asian citrus psyllid is not completely understood. th ...201627441376
annotation of the asian citrus psyllid genome reveals a reduced innate immune system.citrus production worldwide is currently facing significant losses due to citrus greening disease, also known as huanglongbing. the citrus greening bacteria, candidatus liberibacter asiaticus (clas), is a persistent propagative pathogen transmitted by the asian citrus psyllid, diaphorina citri kuwayama (hemiptera: liviidae). hemipterans characterized to date lack a number of insect immune genes, including those associated with the imd pathway targeting gram-negative bacteria. the d. citri draft ...201627965582
morphological abnormalities and cell death in the asian citrus psyllid (diaphorina citri) midgut associated with candidatus liberibacter asiaticus.candidatus liberibacter asiaticus (clas) is a phloem-limited, gram-negative, fastidious bacterium that is associated with the development of citrus greening disease, also known as huanglongbing (hlb). clas is transmitted by the asian citrus psyllid (acp) diaphorina citri, in a circulative manner. two major barriers to transmission within the insect are the midgut and the salivary glands. we performed a thorough microscopic analysis within the insect midgut following exposure to clas-infected cit ...201627630042
invasive mutualisms between a plant pathogen and insect vectors in the middle east and brazil.complex multi-trophic interactions in vectorborne diseases limit our understanding and ability to predict outbreaks. arthropod-vectored pathogens are especially problematic, with the potential for novel interspecific interactions during invasions. variations and novelties in plant-arthropod-pathogen triumvirates present significant threats to global food security. we examined aspects of a phytoplasma pathogen of citrus across two continents. 'candidatus phytoplasma aurantifolia' causes witches' ...201628083099
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