The Experts below are selected from a list of 1521 Experts worldwide ranked by ideXlab platform

Philip A Stansly - One of the best experts on this subject based on the ideXlab platform.

  • optimizing production of tamarixia radiata hymenoptera eulophidae a parasitoid of the Citrus Greening Disease vector diaphorina citri hemiptera psylloidea
    Biological Control, 2017
    Co-Authors: Xulin Chen, Monica Triana, Philip A Stansly
    Abstract:

    Abstract Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) established and spread throughout Florida following first release in 1999 for control of the Asian Citrus psyllid (ACP) Diaphorina citri (Kuwayama) (Hemiptera: Psylloidea). Nevertheless, persistence of the pest and continued losses from Citrus Greening Disease have created the need for more effective biological control, including mass rearing and augmentative release of T. radiata . However, information is lacking on efficiency of current rearing methods including ways to increase the proportion of hosts parasitized as a function of host density. This “functional response” has been studied under lab conditions, but not yet related to mass rearing efficiency. Three release rates of D. citri per flush shoot, four host: T. radiata ratios and five photophases were evaluated. Results indicated that 20 psyllid adults per flush provided optimal host density without excessive stickiness from honeydew. Sixty T. radiata females per cage of approximately 4800 nymphs provided most economical use of wasps and hosts. Progeny sex ratio was not influenced by parental sex ratio. A photophase of 12 h maintained high fecundity. A type II functional response was observed with estimates of handling time and searching efficiency falling within previously estimated ranges. Modifications in rearing parameters suggested by this study improved parasitoid production three-fold compared to previous procedures.

  • Liviidae) Vector of Huanglongbing
    2016
    Co-Authors: Psyllid Diaphorina Citri, Jawwad A Qureshi, Barry C. Kostyk, Philip A Stansly
    Abstract:

    Diaphorina citri vectors pathogens that cause ‘huanglongbing ’ or Citrus Greening Disease which poses a serious threat to Citrus production worldwide. Vector suppression is critical to reduce Disease spread. Efficacy is a main concern when choosing an insecticide. Insecticidal treatments of 49 products or 44 active ingredients (a.i) labeled or experimental were field tested between 2005–2013 as foliar sprays (250 treatments, 39 a.i) or soil applications (47 treatments, 9 a.i) to control D. citri in Citrus. A combined effect of nymphal and adult suppression in response to sprays of 23 insecticides representing 9 modes of action (MoA) groups and 3 unknown MoA provided more than 90 % reduction of adult D. citri over 24–68 days. Observable effects on nymphs were generally of shorter duration due to rapid maturation of flush. However, reduction of 76–100 % nymphs or adults over 99–296 days was seen on young trees receiving drenches of the neonicotinoids imidacloprid, thiamethoxam or clothianidin (MoA 4A) and a novel anthranilic diamide, cyantraniliprole (MoA 28). Effective products identified for foliar sprays t

  • avoidance of parasitized hosts by female wasps of tamarixia radiata hymenoptera eulophidae parasitoid of diaphorina citri hemiptera liviidae vector of Citrus Greening Disease
    Florida Entomologist, 2016
    Co-Authors: Xulin Chen, Gabriela Pavan Bordini, Philip A Stansly
    Abstract:

    Summary Female wasps of Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) avoided probing or parasitizing hosts that the same or another female wasp had already parasitized. Furthermore, they discriminated against hosts parasitized by herself versus another female wasp when these were the only choices. Nevertheless, incidence of superparasitism was low under these conditions compared with normal parasitism, underscoring the strength of the deterrent mark.

  • ENY-739 Biology and Management of the Asian Citrus Psyllid,
    2015
    Co-Authors: Diaphorina Citri Kuwayama, In Florida Citrus, Michael E. Rogers, Philip A Stansly
    Abstract:

    pest of Citrus in Florida. Shortly after the psyllid was first discovered in Florida in 1998, it was determined to be distributed throughout the Citrus-growing areas of the state, making eradication impossible (Halbert and Manjunath, 2004). Since its establishment, the Asian Citrus psyllid has been considered a pest of moderate significance in Florida Citrus. Direct damage caused by psyllid feeding is restricted to young tender leaves, thus control measures were previ-ously only justified for non-bearing Citrus which produce flush throughout the growing season. The discovery of Citrus Greening Disease in Florida in August 2005 has changed the status of the psyllid, which is a vector of this pathogen, from a pest of moderate importance to one requiring management in all stages of Citrus production. No control method will totally eliminate psyllids and the ris

  • biology of tamarixia radiata hymenoptera eulophidae parasitoid of the Citrus Greening Disease vector diaphorina citri hemiptera psylloidea a mini review
    Florida Entomologist, 2014
    Co-Authors: Xulin Chen, Philip A Stansly
    Abstract:

    Tamarixia radiata (Waterston) (Hymenoptera: Eulophidae) is an ectoparasitoid of the Asian Citrus psyllid (ACP) Diaphorina citri Kuwayama (Hemiptera: Psylloidea) a Citrus pest and vector of huanglongbing (HLB) or Citrus Greening Disease. First described from what is now Pakistan, the parasitoid has been introduced deliberately or inadvertently throughout Asia and the Americas wherever the psyllid now occurs. Interest in T. radiata for biological control of D. citri has grown in response to continued spread of ACP and HLB, and the evident searching and colonization capabilities of the parasitoid. Mass release is seen as a potential strategy to augment area wide management of D. citri, particularly where pesticides are not extensively used. Efficient mass rearing and eventual success of these programs will require the best possible information on biology of T. radiata including life history parameters, host relationships, sensory perception, environmental responses and genetics. Much early literature on T. radiata is in Chinese and therefore inaccessible to those not able to read the language. The present review covers the literature through 2014. The intent is to summarize what is known about biology of T. radiata to aid research efforts, with the objective of contributing to more effective biological control of this pest.

Michelle Heck - One of the best experts on this subject based on the ideXlab platform.

  • proteomic polyphenism in color morphotypes of diaphorina citri insect vector of Citrus Greening Disease
    Journal of Proteome Research, 2021
    Co-Authors: Saeed Hosseinzadeh, Michelle Heck, Kevin J. Howe, John S. Ramsey, Steven A Higgins, Michael H Griggs, Louela A Castrillo
    Abstract:

    Diaphorina citri is a vector of "Candidatus Liberibacter asiaticus" (CLas), associated with Citrus Greening Disease. D. citri exhibit at least two color morphotypes, blue and non-blue, the latter including gray and yellow morphs. Blue morphs have a greater capacity for long-distance flight and transmit CLas less efficiently as compared to non-blue morphs. Differences in physiology and immunity between color morphs of the insect vector may influence Disease epidemiology and biological control strategies. We evaluated the effect of CLas infection on color morph and sex-specific proteomic profiles of D. citri. Immunity-associated proteins were more abundant in blue morphs as compared to non-blue morphs but were upregulated at a higher magnitude in response to CLas infection in non-blue insects. To test for differences in color morph immunity, we measured two phenotypes: (1) survival of D. citri when challenged with the entomopathogenic fungus Beauveria bassiana and (2) microbial load of the surface and internal microbial communities. Non-blue color morphs showed higher mortality at four doses of B. bassinana, but no differences in microbial load were observed. Thus, color morph polyphenism is associated with two distinct proteomic immunity phenotypes in D. citri that may impact transmission of CLas and resistance to B. bassiana under some conditions.

  • candidatus liberibacter asiaticus minimally alters expression of immunity and metabolism proteins in hemolymph of diaphorina citri the insect vector of huanglongbing
    Journal of Proteome Research, 2018
    Co-Authors: David G Hall, Michelle Heck, Angela Kruse, Michael J. Maccoss, J S Ramsey, Richard J Johnson
    Abstract:

    Huanglongbing (HLB), also known as Citrus Greening Disease, is the most serious Disease of Citrus plants. It is associated with the Gram-negative bacterium ‘Candidatus Liberibacter asiaticus’ (CLas), which is transmitted between host plants by the hemipteran insect vector Diaphorina citri in a circulative, propagative manner involving specific interactions with various insect tissues including the hemolymph, fluid that occupies the body cavity akin to insect blood. High resolution quantitative mass spectrometry was performed to investigate the effect of CLas exposure on D. citri hemolymph at the proteome level. In contrast to the broad proteome effects on hundreds of proteins and a diverse array of metabolic pathways previously reported in gut and whole insect proteome analyses, the effect of CLas on the hemolymph was observed to be highly specific, restricted to key immunity and metabolism pathways, and lower in magnitude than that previously observed in the whole insect body and gut. Vitellogenins were ...

  • diaphorina citri nymphs are resistant to morphological changes induced by candidatus liberibacter asiaticus in midgut epithelial cells
    Infection and Immunity, 2018
    Co-Authors: Marina Mann, Eldesouky Ammar, Robert G Shatters, Somayeh Fattahhosseini, Richard R Stange, Ericarose Warrick, Kasie Sturgeon, Michelle Heck
    Abstract:

    "Candidatus Liberibacter asiaticus" is the causative bacterium associated with Citrus Greening Disease. "Ca Liberibacter 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 insects reared on healthy or "Ca Liberibacter asiaticus"-infected Citrus trees using quantitative PCR, confocal microscopy, and mitochondrial superoxide staining for evidence of oxidative stress. Consistent with its classification as propagative, "Ca Liberibacter asiaticus" titers were higher in adults than in nymphs. Our previous work showed that adult D. citri insects have basal levels of karyorrhexis (fragmentation of the nucleus) in midgut epithelial cells, which is increased in severity and frequency in response to "Ca Liberibacter asiaticus." Here, we show that nymphs exhibit lower levels of early-stage karyorrhexis than adults and are refractory to the induction of advanced karyorrhexis by "Ca Liberibacter asiaticus" in the midgut epithelium. MitoSox Red staining showed that guts of infected adults, particularly males, experienced oxidative stress in response to "Ca Liberibacter asiaticus." A positive correlation between the titers of "Ca Liberibacter asiaticus" and the Wolbachia endosymbiont was observed in adult and nymph midguts, suggesting an interplay between these bacteria during development. We hypothesize that the resistance of the nymph midgut to late-stage karyorrhexis through as yet unknown molecular mechanisms benefits "Ca Liberibacter asiaticus" for efficient invasion of midgut epithelial cells, which may be a factor explaining the developmental dependency of "Ca Liberibacter asiaticus" acquisition by the vector.

  • Hoyt_ACPmetagenomicsPosterSummer2017.pdf
    2017
    Co-Authors: Stephanie Hoyt, Surya Saha, John Ramsey, Lukas Mueller, Michelle Heck
    Abstract:

    Citrus Greening Disease, or Huanglongbing (HLB) has infected Citrus trees around the world. HLB is associated with the bacterium ‘Candidatus Liberibacter asiaticus’ (CLas), and is transmitted by Diaphorina citri, also known as the Asian Citrus psyllid (ACP) [1]. ACP is known to have the endosymbionts Wolbachia, Carsonella, and Profftella, and it is possible that other bacteria are associated with the ACP at lower abundance. The objective of this project is to utilize metagenomic pipelines in order to analyze whole-body ACP DNA sequences for differences in taxonomy and abundance of endosymbionts.

  • Taxonomic Analysis of the Endosymbionts in the Asian Citrus Psyllid through Metagenomics
    2017
    Co-Authors: Stephanie Hoyt, Surya Saha, John Ramsey, Lukas Mueller, Michelle Heck
    Abstract:

    Citrus Greening Disease, or Huanglongbing (HLB) has infected Citrus trees around the world. HLB is associated with the bacterium ‘Candidatus Liberibacter asiaticus’ (CLas), and is transmitted by Diaphorina citri, also known as the Asian Citrus psyllid (ACP) [1]. ACP is known to have the endosymbionts Wolbachia, Carsonella, and Profftella, and it is possible that other bacteria are associated with the ACP at lower abundance. The objective of this project is to utilize metagenomic pipelines in order to analyze whole-body ACP DNA sequences for differences in taxonomy and abundance of endosymbionts.

Wayne B. Hunter - One of the best experts on this subject based on the ideXlab platform.

  • Annotation of chitin biosynthesis genes in Diaphorina citri, the Asian Citrus psyllid
    'GigaScience Press', 2021
    Co-Authors: Sherry Miller, Wayne B. Hunter, Prashant S Hosmani, Teresa D Shippy, Mirella Flores-gonzalez, Susan J. Brown, Lukas A. Mueller, Blessy Tamayo, Tom D’elia, Surya Saha
    Abstract:

    The polysaccharide chitin is critical for the formation of many insect structures, including the exoskeleton, and is required for normal development. Here we report the annotation of three genes from the chitin synthesis pathway in the Asian Citrus psyllid, Diaphorina citri (Hemiptera: Liviidae), the vector of Huanglongbing (Citrus Greening Disease). Most insects have two chitin synthase (CHS) genes but, like other hemipterans, D. citri has only one. In contrast, D. citri is unusual among insects in having two UDP-N-acetylglucosamine pyrophosphorylase (UAP) genes. One of the D. citri UAP genes is broadly expressed, while the other is expressed predominantly in males. Our work helps pave the way for potential utilization of these genes as pest control targets to reduce the spread of Huanglongbing

  • anatomical study of the female reproductive system and bacteriome of diaphorina citri kuwayama insecta hemiptera liviidae using micro computed tomography
    Scientific Reports, 2020
    Co-Authors: Ignacio Albaalejandre, Javier Albatercedor, Wayne B. Hunter
    Abstract:

    Huanglongbing (HLB) (Citrus Greening Disease) is one of the most serious bacterial Diseases of Citrus. It is caused by (1) Candidatus Liberibacter africanus, transmitted by Trioza erytreae and (2) C.L. asiaticus and C.L. americanus, transmitted by Diaphorina citri. As part of a multidisciplinary project on D. citri (www.CitrusGreening.org), we made a detailed study, using micro-computed tomography, of the female abdominal terminalia, reproductive system (ovaries, accessory glands, spermatheca, colleterial (= cement) gland, connecting ducts, and ovipositor) and bacteriome, which we present here. New terms and structures are introduced and described, particularly concerning the spermatheca, ovipositor and bacteriome. The quality of images and bacteriome reconstructions are comparable, or clearer, than those previously published using a synchrotron or fluorescence in situ hybridisation (FISH). This study: reviews knowledge of the female reproductive system and bacteriome organ in D. citri; represents the first detailed morphological study of D. citri to use micro-CT; and extensively revises existing morphological information relevant to psylloids, hemipterans and insects in general. High quality images and supplementary videos represent a significant advance in knowledge of psylloid anatomy and are useful tools for future research and as educational aids.

  • Characterization of bacterial endosymbionts and systems biology resources for Diaphorina citri, insect vector for the Citrus Greening Disease
    2019
    Co-Authors: Stephanie Hoyt, Wayne B. Hunter, Prashant S Hosmani, Mirella Flores-gonzalez, Susan J. Brown, Lukas A. Mueller, Surya Saha
    Abstract:

    The Asian Citrus psyllid (Diaphorina citri Kuwayama) is the insect vector of the bacterium Ca. Liberibacter asiaticus (CLas), the causal agent for Citrus Greening or Huanglongbing Disease which threatens the Citrus industry worldwide. There is evidence that CLas interacts with the known endosymbionts of D. citri: Wolbachia, Ca. Profftella armatura, and Ca. Carsonella ruddii. Profftella and Carsonella are primary endosymbionts present in the bacteriome of the psyllid, while Wolbachia is present in the bacteriome as well as other tissues, notably in the gut. Profftella likely plays a defensive role in D. citri, while Carsonella is associated with amino acid synthesis and nutrition. Wolbachia is commonly found in insects and has been reported to have various roles, including reproductive effects. Wolbachia, Profftella, and Carsonella are all known to be inherited vertically through the eggs; however, there is also evidence in other insects of Wolbachia being transmitted horizontally. A previous version of the D. citri genome, v1.1, was contaminated with bacterial contigs. We sequenced the 450Mb psyllid genome to 80X coverage with Pacbio long reads. The Canu assembler followed by Dovetail Chicago-based scaffolding was used to create an improved assembly (v2.0) with a contig N50 of 758.7kb and 1906 contigs. Endosymbiont sequences were extracted from the new D. citri genome assembly and verified for coverage against Pacbio and Illumina data, as well as against published reference genomes. Scaffolds from SSPACE were annotated with prokka and analyzed using Orthofinder and BRIG for gene copy number and conserved synteny.Annotation and subsequent orthology analysis of the Profftella genome shows that all orthogroups conserved among the published reference genomes are also present in our assembly. Orthology analysis of the Carsonella genome shows >90% of conserved orthogroups to be present. We have 10 scaffolds that represent multiple Wolbachia strains, and together cover 557/559 conserved orthogroups. We have also assembled the mitochondrial organellar genome. This is the first report of the genomes of the primary endosymbionts and the mitochondria from D. citri sourced from Florida. We have designed a web portal with genomics and bioinformatics resources for the vector D. citri including endosymbionts, the host Citrus (C. clementina and C. sinensis) and multiple pathogens including CLas for the Citrus Greening Disease. We have used Biocyc Pathway Tools databases to model biochemical pathways within each organism that can be used to explore the entire Disease complex. All tools like JBrowse, Biocyc, Blast and Psyllid Expression Network connect to a central database containing gene models for Citrus, ACP and multiple Ca. Liberibacter pathogens. The portal can be accessed at https://CitrusGreening.org/

  • An Animated Detailing of the Alimentary Canal of the Asian Citrus Psyllid, with Special Reference to the Configuration and Function of the Filter Chamber
    2019
    Co-Authors: Joseph M. Cicero, Wayne B. Hunter, Surya Saha, Liliana M. Cano, Susan J. Brown
    Abstract:

    The high volume of water present in the Citrus phloem-derived foodstream would be toxic to the Asian Citrus psyllid were it not for a complexation of alimentary canal that forms a kidney of sorts, called the filter chamber. This, and other digestive system organs are heavily laden with Ca. Liberibacter asiaticus, causal agent of Citrus Greening Disease. Certain members of the deprecated order Homoptera have a highly modified alimentary canal wherein the esophagus, anterior midgut, posterior midgut and hindgut are collocated and complexed into an apparently paraphyletic structure called the filter chamber that acts as a kidney, removing the high volume of water from the hostplant foodstream and shunting it directly to the anus. This organ, and the mesal length of the midgut, are of very similar construction in the potato psyllid and the Asian Citrus psyllid, and both are mobbed by their respective Liberibacter species. The presentation herein is an animation crafted to allow for broad scientific audiences to understand basic alimentary canal anatomy and functionality of, in particular, the Asian Citrus psyllid

  • evaluation of north american asian Citrus psyllid hemiptera liviidae population genetics using cytochrome p450 melt curve analysis
    bioRxiv, 2018
    Co-Authors: J F Maciasvelasco, Wayne B. Hunter, R T Brunson, Blake Bextine
    Abstract:

    The Asian Citrus Psyllid (ACP) (Diaphorina citri) is a Hemipteran which feeds on Citrus and is the principal vector of the pathogen Candidatus Liberibacter asiaticus (Las); the primary causal agent of Huanglongbing (HLB) or Citrus Greening Disease. Currently HLB is the single greatest threat to the American Citrus industry. Previous work has shown that that Cytochrome P450 (CYP4) genes are associated with insecticidal resistance to neonicotinoid insecticides. Infection by Las has also been shown to affect the expression of CYP4 genes. In this study the genetic relationships of ACP populations was evaluated using melting curve analysis of CYP4 genes. Principal component analysis shows the presence of two potential haplotypes. The groups identified by principal component analysis are significantly different from each other (P < 0.05) for all CYP4 genes tested. All populations are most likely within 2-3 mutations of each other. The existence of these mutations sheds light on the potential evolution of ACP in North America. Indicating either coevolution with Las or difference in imidacloprid basal selective pressure in the United States and Mexico.

Lukasz L. Stelinski - One of the best experts on this subject based on the ideXlab platform.

  • asian Citrus psyllid adults inoculate huanglongbing bacterium more efficiently than nymphs when this bacterium is acquired by early instar nymphs
    Scientific Reports, 2020
    Co-Authors: Eldesouky Ammar, Lukasz L. Stelinski, Justin George, Kasie Sturgeon, Robert G Shatters
    Abstract:

    The Asian Citrus psyllid (Diaphorina citri) transmits the bacterium ‘Candidatus Liberibacter asiaticus’ (CLas), which causes huanglongbing (Citrus Greening) Disease, in a circulative-propagative manner. We compared CLas inoculation efficiency of D. citri nymphs and adults into healthy (uninfected) citron leaves when both vector stages were reared from eggs on infected plants. The proportion of CLas-positive leaves was 2.5% for nymphs and 36.3% for adults. CLas acquisition by early instar nymphs followed by dissections of adults and 4th instar nymphs revealed that CLas bacterium had moved into the head-thorax section (containing the salivary glands) in 26.7–30.0% of nymphs and 37–45% of adults. Mean Ct values in these sections were 31.6–32.9 and 26.8–27.0 for nymphs and adults, respectively. Therefore, CLas incidence and titer were higher in the head-thorax of adults than in nymphs. Our results suggest that following acquisition of CLas by early instar D. citri nymphs, emerging adults inoculate the bacteria into Citrus more efficiently than nymphs because adults are afforded a longer latent period necessary for multiplication and/or translocation of CLas into the salivary glands of the vector. We propose that CLas uses D. citri nymphs mainly for pathogen acquisition and multiplication, and their adults mainly for pathogen inoculation and spread.

  • formic and acetic acids in degradation products of plant volatiles elicit olfactory and behavioral responses from an insect vector
    Chemical Senses, 2016
    Co-Authors: Justin George, Lukasz L. Stelinski, Paul S Robbins, Rocco T Alessandro, Stephen L Lapointe
    Abstract:

    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. Two peaks elicited large antennal responses and were identified as acetic and formic acids. Probing by D. citri of a wax substrate containing odorants was significantly increased by a blend of formic and acetic acids compared with either compound separately or blends containing β-ocimene and/or citral. Response surface modeling based on a 4-component mixture design and a 2-component mixture-amount design predicted an optimal probing response on wax substrate containing a blend of formic and acetic acids. Our study suggests that formic and acetic acids play a role in host selection by D. citri and perhaps by phytophagous insects in general even when parent compounds from which they are derived are not active. These results have implications for the investigation of arthropod olfaction and may lead to elaboration of attract-and-kill formulations to reduce nontarget effects of chemical control in agriculture.

  • Citrus Genotypes.
    2016
    Co-Authors: Denis S. Willett, Lukasz L. Stelinski, Justin George, Nora S. Willett, Stephen L Lapointe
    Abstract:

    Nine Citrus genotypes and associated varieties used in this analysis. Trifoliates and trifoliate hybrids are being considered for their potential tolerance to Citrus Greening Disease.

  • Resistance to pathogen transmission.
    2016
    Co-Authors: Denis S. Willett, Lukasz L. Stelinski, Justin George, Nora S. Willett, Stephen L Lapointe
    Abstract:

    Phloem feeding (feeding states E1 and E2) by Asian Citrus psyllid on trifoliate and non-trifoliate Citrus varieties. The vertical axis is the median percent time an insect spends on each bout of phloem feeding, where pathogen transmission and inoculation can occur. Trifoliate varieties are significantly more (α = 0.05) resistant to phloem feeding, an explanation for observed tolerance of trifoliate varieties to Citrus Greening Disease.

  • Machine Learning for Characterization of Insect Vector Feeding.
    Public Library of Science (PLoS), 2016
    Co-Authors: Denis S. Willett, Lukasz L. Stelinski, Justin George, Nora S. Willett, Stephen L Lapointe
    Abstract:

    Insects that feed by ingesting plant and animal fluids cause devastating damage to humans, livestock, and agriculture worldwide, primarily by transmitting pathogens of plants and animals. The feeding processes required for successful pathogen transmission by sucking insects can be recorded by monitoring voltage changes across an insect-food source feeding circuit. The output from such monitoring has traditionally been examined manually, a slow and onerous process. We taught a computer program to automatically classify previously described insect feeding patterns involved in transmission of the pathogen causing Citrus Greening Disease. We also show how such analysis contributes to discovery of previously unrecognized feeding states and can be used to characterize plant resistance mechanisms. This advance greatly reduces the time and effort required to analyze insect feeding, and should facilitate developing, screening, and testing of novel intervention strategies to disrupt pathogen transmission affecting agriculture, livestock and human health

David G Hall - One of the best experts on this subject based on the ideXlab platform.

  • candidatus liberibacter asiaticus minimally alters expression of immunity and metabolism proteins in hemolymph of diaphorina citri the insect vector of huanglongbing
    Journal of Proteome Research, 2018
    Co-Authors: David G Hall, Michelle Heck, Angela Kruse, Michael J. Maccoss, J S Ramsey, Richard J Johnson
    Abstract:

    Huanglongbing (HLB), also known as Citrus Greening Disease, is the most serious Disease of Citrus plants. It is associated with the Gram-negative bacterium ‘Candidatus Liberibacter asiaticus’ (CLas), which is transmitted between host plants by the hemipteran insect vector Diaphorina citri in a circulative, propagative manner involving specific interactions with various insect tissues including the hemolymph, fluid that occupies the body cavity akin to insect blood. High resolution quantitative mass spectrometry was performed to investigate the effect of CLas exposure on D. citri hemolymph at the proteome level. In contrast to the broad proteome effects on hundreds of proteins and a diverse array of metabolic pathways previously reported in gut and whole insect proteome analyses, the effect of CLas on the hemolymph was observed to be highly specific, restricted to key immunity and metabolism pathways, and lower in magnitude than that previously observed in the whole insect body and gut. Vitellogenins were ...

  • prolonged phloem ingestion by diaphorina citri nymphs compared to adults is correlated with increased acquisition of Citrus Greening pathogen
    Scientific Reports, 2018
    Co-Authors: Justin George, David G Hall, Eldesouky Ammar, Robert G Shatters, Stephen L Lapointe
    Abstract:

    Citrus Greening Disease (huanglongbing), currently the most destructive Citrus Disease worldwide, is putatively caused by Candidatus Liberibacter asiaticus (CLas), a phloem-limited bacterium transmitted by the Asian Citrus psyllid Diaphorina citri. Electrical penetration graph (EPG) recordings over 42 h were performed to compare the feeding behavior of D. citri adults and 4th or 5th instar nymphs feeding on CLas-infected or healthy citron plants. Nymphs performed more individual bouts of phloem ingestion (E2) and recorded longer phloem ingestion total time compared with adults, whereas adults performed more bouts of xylem ingestion (G) and recorded greater total time of xylem ingestion compared with nymphs. Quantitative polymerase chain reaction tests indicated that 58% of nymphs and 6% of adults acquired CLas during the 42 h EPG-recorded feeding on infected plants. In a histological study, a greater proportion of salivary sheaths produced by nymphs were branched compared to those of the adults. Our results strongly suggest that more bouts and longer feeding time in the phloem by nymphs may explain their more efficient CLas acquisition from infected plants compared to adults. This is the first EPG study comparing nymphs and adults of D. citri on healthy and infected Citrus plants in relation to CLas acquisition.

  • Crystal structure of diaphorin methanol monosolvate isolated from Diaphorina citri Kuwayama, the insect vector of Citrus Greening Disease
    International Union of Crystallography, 2018
    Co-Authors: Marian D. Szebenyi, David G Hall, Irina Kriksunov, Kevin J. Howe, John S. Ramsey, Michelle L. Heck, Stuart B. Krasnoff
    Abstract:

    The title compound C22H39NO9·CH3OH [systematic name: (S)-N-((S)-{(2S,4R,6R)-6-[(S)-2,3-dihydroxypropyl]-4-hydroxy-5,5-dimethyltetrahydro-2H-pyran-2-yl}(hydroxy)methyl)-2-hydroxy-2-[(2R,5R,6R)-2-methoxy-5,6-dimethyl-4-methylenetetrahydro-2H-pyran-2-yl]acetamide methanol monosolvate], was isolated from the Asian Citrus psyllid, Diaphorina citri Kuwayama, and crystallizes in the space group P21. `Candidatus Profftella armatura' a bacterial endosymbiont of D. citri, biosynthesizes diaphorin, which is a hybrid polyketide–nonribosomal peptide comprising two highly substituted tetrahydropyran rings joined by an N-acyl aminal bridge [Nakabachi et al. (2013). Curr. Biol. 23, 1478–1484]. The crystal structure of the title compound establishes the complete relative configuration of diaphorin, which agrees at all nine chiral centers with the structure of the methanol monosolvate of the di-p-bromobenzoate derivative of pederin, a biogenically related compound whose crystal structure was reported previously [Furusaki et al. (1968). Tetrahedron Lett. 9, 6301–6304]. Thus, the absolute configuration of diaphorin is proposed by analogy to that of pederin

  • No claim to original US government works
    2016
    Co-Authors: Laura M. Boykin, David G Hall, Wayne B. Hunter, Ruth Ann Bagnall, Donald R. Frohlich, Catherine S Katsar, Cindy L Mckenzie, Rosemarie C, Robert G Shatters
    Abstract:

    Twelve polymorphic microsatellite loci from the Asian Citrus psyllid, Diaphorina citri Kuwayama, the vector for Citrus Greening Disease, huanglongbin

  • RESEARCH ARTICLE Metabolic Interplay between the Asian Citrus Psyllid and Its Profftella Symbiont: An Achilles ’ Heel of the Citrus Greening Insect Vector
    2016
    Co-Authors: John S. Ramsey, David G Hall, Wayne B. Hunter, Richard S. Johnson, Jason S. Hoki, Angela Kruse, Jaclyn Mahoney, Mark E. Hilf, Frank C. Schroeder, Michael J. Maccoss
    Abstract:

    ‘Candidatus Liberibacter asiaticus ’ (CLas), the bacterial pathogen associated with Citrus Greening Disease, is transmitted by Diaphorina citri, the Asian Citrus psyllid. Interactions among D. citri and its microbial endosymbionts, including ‘Candidatus Profftella armatura’, are likely to impact transmission of CLas. We used quantitative mass spectrometry to com-pare the proteomes of CLas(+) and CLas(-) populations of D. citri, and found that proteins involved in polyketide biosynthesis by the endosymbiont Profftella were up-regulated in CLas(+) insects. Mass spectrometry analysis of the Profftella polyketide diaphorin in D. citri metabolite extracts revealed the presence of a novel diaphorin-related polyketide and the ratio of these two polyketides was changed in CLas(+) insects. Insect proteins differentially expressed between CLas(+) and CLas(-) D. citri included defense and immunity proteins, proteins involved in energy storage and utilization, and proteins involved in endocytosis