Objectives

Background information
HLB is considered to be the most devastating disease of citrus fruits. This is due to its rapid rate of spread, the aggressiveness of its symptoms, the high economic losses it causes, the difficulty of preventing new infections and the lack of sustainable control mechanisms. HLB now affects all varieties and rootstocks of citrus fruits, however, resistance has been identified in related genera of the Aurantioideae subfamily. This disease, which originated in Southeast Asia, has spread in just over a decade in almost all citrus-growing regions of the world. China, Florida (United States) and Brazil, the world's largest citrus fruit producers, are affected by HLB and suffer considerable economic losses. HLB is caused by three species of bacteria of the genus Candidatus Liberibacter, transmitted by the insects Trioza erytreae and Diaphorina citri. Trioza erytreae has been detected in the Iberian Peninsula.

Objectives of the project
The objective of the preHLB project is to develop and implement a comprehensive emergency plan to protect European citrus production from HLB vectors and causal agents and to generate new solutions for managing the disease through a multidisciplinary approach, in collaboration with partners in the Americas and Asia with strong expertise in the disease. The specific objectives of the project are as follows:

•  implementation of short-term preventive actions and tools to limit the risk of introducing HLB,
•  implementation of medium-term HLB surveillance and control strategies: up to 100,000 ha will be monitored to obtain information on potential infection and vector dynamics in high-risk sub-areas. This axis will be based on the development of new detection tools.
•   development of long-term research on vector biology, host / vector / pathogen interactions leading to: - effective exploitation of identified sources of resistance in citrus-related genera through genetic, genomic and biotechnological research, and - development of new vector or bacterial control tools, such as new effectors, metabolites, bio-stimulants and biopesticides.

Researchers of AGAP's SEAPAG team based in Montpellier,Corsica and Guadeloupe coordinate research in genetics and genomics ofidentified resistance in Citrus-related genera and study the potential of thesegenetic resources as rootstocks or interstock as well as broodstock for citrusbreeding projects.

Researchers of AGAP's SEAPAG team based in Montpellier, Corsica and Guadeloupe coordinate research in genetics and genomics of identified resistance in Citrus-related genera and study the potential of these genetic resources as rootstocks or interstock as well as broodstock for citrus breeding projects.