CitrusGreening.org

The citrus greening disease (also called huanglongbing) has devastated the Florida citrus industry, and is now in CA and TX. Fruit from infected trees is safe to eat, but production is reduced so much that citrus may cease to be inexpensive and broadly available. If you are a citrus lover you should know that massive research efforts, including this project, are underway to keep citrus affordable and plentiful. See impact on US production..

Citrus Greening Solutions is a USDA NIFA project.

Credit: Cilia lab

News

Citrus added to VIGS tool

Citrus genomes are now available in the VIGS tool to design virus induced gene silencing experiments on C. sinensis and C. clementina. More details about the tool are available in the publication. Please report any issues using the contact form.

New pathway databases added for C. sinensis and C. clementina

Updated metabolic pathway databases for C. sinensis and C. clementina have been constructed with the latest version of BioCyc Pathway Tools and MetaCyc. This is a collaboration with the Main lab at WSU. The new PGDBs are C clementina Cyc v3, C sinensis Cyc v3 and C sinensis Cyc v4.

Diaphorina citri stylet biogenesis paper is published!

Asian citrus psyllid stylets and potato psyllid stylets are comparable in structure including the stylet end-caps of the adult and atria of the pharate adult. Apparent presence of epicuticle cells at the stylet base is not proven. Of interest, Liberibacter may possibly use the stylet replacement apparatus for transmission. Please see Arthropod Structure & Development. Volume 47, Issue 5, September 2018, Pages 542-551 for more details.

Diaphorina citri alimentary canal animation is online

Psyllids have a highly modified alimentary canal wherein the esophagus, anterior midgut, posterior midgut and hindgut are co-located and complexed into an apparently paraphyletic structure called the filter chamber. The animation is crafted to allow for broad scientific audiences to understand basic alimentary canal anatomy and functionality of the Asian citrus psyllid.

Economic impact of citrus industry in California

The total economic impact of the iconic citrus industry is $7.117 billion according to a new study commissioned by the Citrus Research Board (CRB). You can read the full report here.

Hunter et al. awarded patent for dsRNA treatment to reduce D. citri in citrus

dsRNA generated from D. citri trehalase gene is effective in reducing fitness and/or survival of D. citri. Thus genetically altered plants expressing the dsRNA and plants to which dsRNA solutions are applied increase D. citri mortality and reduce D. citri infestation. Read more

Diaphorina citri stylet biogenesis animation is online

The manufacture of new stylets (stylet biogenesis) is an extremely complex process that has been detailed in the potato psyllid. The animation shows examples of key features of the potato psyllid's process that are present in Diaphorina citri, indicating that both are comparable.

Missed the webinar for new Diaphorina citri v2.0 genome release?

The slides are available on slideshare. The v2.0 reference assembly and official Gene Set (v2.0) can be downloaded from the FTP site. You can browse the genome using jbrowse and explore the gene pages.

Featured publications

Characterization and purification of proteins suitable for the production of antibodies against ‘Ca. Liberibacter asiaticus’ Liu et al. (2017) Protein Expression and Purification

Susceptibility of Diaphorina citri (Hemiptera: Liviidae) and Its Parasitoid Tamarixia radiata (Hymenoptera: Eulophidae) to Entomopathogenic Fungi under Laboratory Conditions Ibarra-Cortés et al. (2017) Neotropical Entomology

Does the scion or rootstock of Citrus sp. affect the feeding and biology of Diaphorina citri Kuwayama (Hemiptera: Liviidae)? Rodrigues Alves et al. (2017) Arthropod-Plant Interactions

Rehabilitation of Huanglongbing-affected Citrus Trees Using Severe Pruning and Enhanced Foliar Nutritional Treatments Rouse et al. (2017) HortScience

Molecular mechanisms behind the accumulation of ATP and H2O2 in citrus plants in response to ‘Candidatus Liberibacter asiaticus’ infection Pitino et al. (2017) Horticulture Research

The influence of bacteria on multi-trophic interactions among plants, psyllids, and pathogen Tamborindeguy et al. (2017) Insect Science

Candidatus Liberibacter asiaticus Encodes a Functional Salicylic Acid (SA) Hydroxylase That Degrades SA to Suppress Plant Defenses Li et al. (2017) APS Journals

LdtR is a master regulator of gene expression in Liberibacter asiaticus Pagliai et al. (2017) Microbial biotechnology

Metabolomic Response to Huanglongbing: Role of Carboxylic Compounds in Citrus sinensis Response to ‘Candidatus Liberibacter asiaticus’ and Its Vector, Diaphorina citri Killiny et al. (2017) Molecular Plant-Microbe Interactions

Research highlights

Diaphorina citri nymphs are resistant to morphological changes induced by "Ca. Liberibacter asiaticus" in midgut epithelial cells

Translation? The gut cells of the Asian citrus psyllid nymphs do not respond the same way to infection by the Huanglongbing bacterial pathogen as adult guts. This was unexpected.
Scientists found a surprising visual difference between how nymph and adult guts of the Asian citrus psyllid (Diaphorina citri) respond to infection by "Ca. Liberibacter asiaticus," the causative bacterial agent of Huanglongbing (HLB), or Citrus greening disease. More

Guts of Asian citrus psyllid adults change on a molecular level when feeding on plants infected with the citrus greening bacterium

Kruse and her colleagues were interested in how CLas interacts with the gut to cross into the blood and be transmitted, and if the presence of CLas causes changes in the cells of the gut. To find out, researchers at the Boyce Thompson Institute and Cornell University began with hundreds of dissected guts from psyllids feeding on either healthy or CLas-infected citrus plants. More

Annotation Updates

C-Type Lectins

Report and protein sequences

C-Type Lectins(CTLs) are calcium dependent extracellular proteins involved in recognition of glycans. A total of 10 models were found and annotated. Refer to C-type lectin gene report for further details. The Basecamp page and FTP site contain the data sets and instructions for annotation.

Relish-like Proteins

Report and protein sequences

Relish-like proteins are transcription factors and are inlvolved in Imd pathway. The Basecamp page and FTP site contain the data sets and instructions for annotation.

Galactoside-Binding Lectins

Report and protein sequences

Galactoside-Binding Lectins (GALEs) or galectins bind to beta-galactoside sugars. GALEs are implicated in innate immunity as they might be involved in microbial recognition and/or phagocytosis. The Basecamp page and FTP site contain the data sets and instructions for annotation.

Events

IOCV XXI and IRCHLB VI meeting

Abstract submissions are now open for the Joint Conference of the International Organization of Citrus Virologists XXI (IOCV XXI) and the International Research Conference on Huanglongbing VI (IRCHLB VI) to be held in Riverside, CA from March 10-15, 2019.

Third Annual CitrusGreening Solutions meeting

The Third Annual CitrusGreening Solutions meeting will be held on Dec 10-12th,2017 at University of California, Davis campus in CA.

International Research Conference on Huanglongbing

The IRCHLB V meeting was held in Orlando, FL from March 15-17th, 2017. See here for more information. The Cilia, Mueller and Shatters labs were represented at the meeting.

Links