Citrus tristeza virus-based RNAi in citrus plants induces gene silencing in Diaphorina citri, a phloem-sap sucking insect vector of citrus greening disease (Huanglongbing)

Citrus tristeza virus (CTV) is one of the most important citrus tree viruses: a graft-transmissible virus that can be vectored by several aphid species. Diaphorina citri is the insect vector of “Candidatus Liberibacter spp.”, a bacterium associated with citrus Huanglongbing (HLB). However, no detailed description of the relationship between CTV and D. citri has been reported. In this study, D. citri adults collected from CTV-infected “Shatangju” mandarin, “Newhall” sweet orange, and “fingered citron” trees in different orchards yielded CTV-positive rates of 40%, 65%, and 95%, respectively, upon detection by conventional PCR. Illumina HiSeq sequencing followed by de novo assembly recovered the primary full CTV genome from the RNA of 30 D. citri adults sampled from CTV-positive citrus plants. Molting and adult emergence did not affect the presence or titers of CTV within the D. citri; however, the persistence of CTV in psyllids varied among different host plant species. Groups of 10 D. citri (from a population 85% CTV-positive) were shown to potentially transmit CTV to two citrus species, “Shatangju” mandarin and “Eureka” lemon, yielding 58.33% and 83.33% CTV-positive plants, respectively. No transmission of CTV to orange jasmine plants occurred. Thus, this study reports on the ability of D. citri to acquire and transmit CTV, making D. citri as a vector of two important citrus pathogens, warranting further attention and investigation.

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Candidatus Liberibacter Asiaticus Manipulates the Expression of Vitellogenin, Cytoskeleton, and Endocytotic Pathway-Related Genes to Become Circulative in Its Vector, Diaphorina citri (Hemiptera: Psyllidae)

10.20944/preprints202005.0389.v1 ◽

2020 ◽

Author(s):

Damini Jaiswal ◽

V. Kavi Sidharthan ◽

Susheel Kumar Sharma ◽

Richa Rai ◽

Nandlal Choudhary ◽

...

Keyword(s):

Differential Regulation ◽

Citrus Greening ◽

Insect Vector ◽

Diaphorina Citri ◽

Citrus Greening Disease ◽

Physiological Processes ◽

Citrus Production ◽

Liberibacter Asiaticus ◽

Greening Disease ◽

Cellular Components

Citrus greening disease or huanglongbing (HLB) caused by Candidatus Liberibacter asiaticus (CLas) limits the citrus production worldwide. CLas is transmitted by the Asian citrus psyllid (ACP), Diaphorina citri (Hemiptera: Psyllidae) in a persistent-propagative manner. Application of insecticides to manage the psyllid vectors and disease is the most common practice. Understanding the molecular interaction between CLas and ACP and interrupting the interrelationship can provide an alternative to insecticides for managing citrus greening disease. Transcriptome analysis of ACP in response to CLas showed differential expression of 3911 genes (2196 up-regulated, and 1715 down-regulated) including the key genes of ACP involved in cytoskeleton synthesis and nutrition-related proteins. Majority of the differentially expressed genes were categorized under molecular function followed by cellular components and biological processes. KEGG pathway analysis showed differential regulation of carbohydrate, nucleotide and energy metabolic pathways, the endocytotic pathway and the defense-related pathways. Differential regulation of genes associated with the key pathways might favors CLas to become systemic and propagate in its insect vector. The study provides an understanding of genes involved in circulation of CLas in ACP. The candidate genes involved in key physiological processes and CLas transmission by ACP would be potential targets for sustainable management of ACP and CLas.

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Targeting juvenile hormone metabolic genes in the Asian citrus psyllid (Diaphorina citri Kuwayama) as a strategy to reduce the spread of citrus greening disease

Journal of Citrus Pathology ◽

10.5070/c411025105 ◽

2014 ◽

Vol 1 (1) ◽

Author(s):

Evelien Van Ekert ◽

D. Borovsky ◽

C. A. Powell ◽

R. D. Cave ◽

R. T. Alessandro ◽

...

Keyword(s):

Juvenile Hormone ◽

Citrus Greening ◽

Asian Citrus Psyllid ◽

Diaphorina Citri ◽

Citrus Greening Disease ◽

Metabolic Genes ◽

Greening Disease

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Asian citrus psyllid adults inoculate huanglongbing bacterium more efficiently than nymphs when this bacterium is acquired by early instar nymphs

Scientific Reports ◽

10.1038/s41598-020-75249-5 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

El-Desouky Ammar ◽

Justin George ◽

Kasie Sturgeon ◽

Lukasz L. Stelinski ◽

Robert G. Shatters

Keyword(s):

Latent Period ◽

Salivary Glands ◽

Emerging Adults ◽

Citrus Greening ◽

Asian Citrus Psyllid ◽

Diaphorina Citri ◽

Citrus Greening Disease ◽

Early Instar ◽

Liberibacter Asiaticus ◽

Greening Disease

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.

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Twelve polymorphic microsatellite loci from the Asian citrus psyllid, Diaphorina citri Kuwayama, the vector for citrus greening disease, huanglongbing

Molecular Ecology Notes ◽

10.1111/j.1471-8286.2007.01831.x ◽

2007 ◽

Vol 7 (6) ◽

pp. 1202-1204 ◽

Cited By ~ 8

Author(s):

LAURA M. BOYKIN ◽

RUTH ANN BAGNALL ◽

DONALD R. FROHLICH ◽

DAVID G. HALL ◽

WAYNE B. HUNTER ◽

...

Keyword(s):

Microsatellite Loci ◽

Citrus Greening ◽

Asian Citrus Psyllid ◽

Diaphorina Citri ◽

Citrus Greening Disease ◽

Greening Disease ◽

Polymorphic Microsatellite

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Improved annotation of the insect vector of citrus greening disease: biocuration by a diverse genomics community

Database ◽

10.1093/database/bax032 ◽

2017 ◽

Vol 2017 ◽

Cited By ~ 25

Author(s):

Surya Saha ◽

Prashant S Hosmani ◽

Krystal Villalobos-Ayala ◽

Sherry Miller ◽

Teresa Shippy ◽

...

Keyword(s):

Citrus Greening ◽

Insect Vector ◽

Citrus Greening Disease ◽

Greening Disease

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Post-Transcriptional Gene Silencing of the p23 Silencing Suppressor of Citrus tristeza virus Confers Resistance to the Virus in Transgenic Mexican Lime

Plant Molecular Biology ◽

10.1007/s11103-005-3129-7 ◽

2006 ◽

Vol 60 (2) ◽

pp. 153-165 ◽

Cited By ~ 76

Author(s):

Carmen Fagoaga ◽

Carmelo López ◽

Alfonso Hermoso de Mendoza ◽

Pedro Moreno ◽

Luis Navarro ◽

...

Keyword(s):

Gene Silencing ◽

Citrus Tristeza Virus ◽

Transcriptional Gene Silencing ◽

Silencing Suppressor ◽

Mexican Lime ◽

Post Transcriptional Gene Silencing ◽

Tristeza Virus ◽

Citrus Tristeza

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Protein interaction networks at the host–microbe interface in Diaphorina citri , the insect vector of the citrus greening pathogen

Royal Society Open Science ◽

10.1098/rsos.160545 ◽

2017 ◽

Vol 4 (2) ◽

pp. 160545 ◽

Cited By ~ 29

Author(s):

J. S. Ramsey ◽

J. D. Chavez ◽

R. Johnson ◽

S. Hosseinzadeh ◽

J. E. Mahoney ◽

...

Keyword(s):

Protein Interaction ◽

Bacterial Pathogen ◽

Pathogen Transmission ◽

Protein Interaction Networks ◽

Interaction Networks ◽

Differentially Expressed ◽

Citrus Greening ◽

Insect Vector ◽

Diaphorina Citri ◽

Citrus Greening Disease

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 microbiota occur during development and regulate vector competency. In support of this hypothesis, more proteins, with greater fold changes, were differentially expressed in response to CLas in adults when compared with nymphs, including insect proteins involved in bacterial adhesion and immunity. Compared with nymphs, adult insects had a higher titre of CLas and the bacterial endosymbionts Wolbachia, Profftella and Carsonella. All Wolbachia and Profftella proteins differentially expressed between nymphs and adults are upregulated in adults, while most differentially expressed Carsonella proteins are upregulated in nymphs. Discovery of protein interaction networks has broad applicability to the study of host–microbe relationships. Using protein interaction reporter technology, a D. citri haemocyanin protein highly upregulated in response to CLas was found to physically interact with the CLas coenzyme A (CoA) biosynthesis enzyme phosphopantothenoylcysteine synthetase/decarboxylase. CLas pantothenate kinase, which catalyses the rate-limiting step of CoA biosynthesis, was found to interact with a D. citri myosin protein. Two Carsonella enzymes involved in histidine and tryptophan biosynthesis were found to physically interact with D. citri proteins. These co-evolved protein interaction networks at the host–microbe interface are highly specific targets for controlling the insect vector responsible for the spread of citrus greening.

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