- Author: Ben Faber
The latest edition of Topics in Subtropics newsletter is out, Elizabeth Fichtner as editor. Read on.
TOPICS IN THIS ISSUE:
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Why has California red scale been so difficult to control?
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Navel Orange Nitrogen Fertilization
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Recent Advances in Understanding the History of Olive Domestication
- Upcoming UC Olive Center Events
- Author: Ben Faber
Hats Off.
The Orange County Master Gardeners have lived up to their name with their website information on citrus. It's a truly impressive information site for not only homeowners, but also growers:
http://mgorange.ucanr.edu/Edible_Plants/?uid=108&ds=530
The “Citrus Problem Diagnosis Chart” is especially work perusing:
- Author: Ben Faber
The proceedings of the 5th International Conference on Huanglongbing (IRCHLB V) is now published, available and citable online through the Journal of Citrus Pathology: http://escholarship.org/uc/iocv_journalcitruspathology
Included are:
Meeting Agenda
Published Abstracts
Joseph (Josy) M. Bové - Selected Photos
Joseph (Josy) M. Bové Dedication
Tribute to Prof. Dr. Joseph Bové
If you download the Bové Dedication pdf file, there is a link near the top of page 3 that will redirect you to the video interview of Prof. Bové. This is the video that we could not show during the meeting due to audiovisual technical difficulties. You must download the pdf for the link to be active. The link is not active when simply viewing the publication online.
The keynote speakers are working on their contributions. These will be available shortly and we will send another email announcement when they become available as well.
sIn the bottom left corner is the Search box for finding authors and topics of the abstracts.
- Author: Ben Faber
Every year growers get together to learn what is being done in the citrus research world that could affect their operations. This June, University of California and the Citrus Research Board are bringing some good talks to three different growing areas. All growers are invited, but RSVPs are appreciated.
- Author: Ben Faber
This is a reminder of the complexity of huanglongbing and the bacterial infection it causes. This abstract is from the HLB Conference in Florida last fall.
4.a.5 Symptom variations and molecular markers that illustrate the HLB complexity
Yongping Duan, Marco Pitino, and Cheryl Armstrong
USHRL-ARS-USDA, Fort Pierce, FL 34945, USA
Huanglongbing (HLB) is a devastating bacterial disease of citrus worldwide due to its intracellular and systemic infection. Various HLB symptoms are observed on different species/varieties of citrus plants: from yellow shoots to blotchy mottle on the leaves, from vein yellowing/vein corky to mosaic/green islands similar to zinc deficiency on the leaves, from whitish discoloration to stunted green leaves, etc. These variations of symptoms, which result from a combination of biotic and abiotic stresses, are not only present on individual plants from a variety but also exist on individual branches of an infected plant. Our results indicated that the adaptation of the bacterial populations, such as the dynamics of ‘Candidatus Liberibacter asiaticus' (Las), plays an important role in the induction of various symptoms and that Las mutations as well as the number and recombination events of Las prophages/phages affect this phenomenon. In addition, the selection of the host plants (resistance/tolerance) for the bacterial populations is also critical for symptom expression during disease progression. Based on severity, we divided HLB symptoms into four grades. It is worth noting that the grades of HLB symptom severity show a positive correlation with our newly identified biomarkers from host plants, and that gene expression profiling of different grades of infected leaves rationalized the differentiation based on the dynamics of these biomarkers. Because of these findings, we propose new approaches that allow for rapid selection of variant citrus plants, including bud sports with greater HLB resistance/tolerance.
Non-Technical Summary: Various symptoms of citrus huanglongbing display in different species/varieties of infected citrus plants. These variations of symptoms are not only present on individual plants from a variety, but also exist on individual branches of an infected plant. We have identified some molecular markers from the citrus plants and Las pathogen that illustrate the HLB complexity. Therefore, we propose new approaches that allow for rapid selection of variant citrus plants, including bud sports with greater HLB resistance/tolerance.
http://www.icc2016.com/images/icc2016/downloads/Abstract_Book_ICC_2016.pdf