Prof. Sijun ZhengYunnan Academy of Agricultural Sciences, Alliance of Bioversity and CIAT, China
Speech Title: The spread of Fusarium wilt of banana TR4 and its comprehensive management
Abstract: Fusarium wilt of banana, caused by Fusarium oxysporum f. sp. cubense (Foc), especially Tropical Race 4 (TR4), seriously threatens banana production worldwide, especially in banana exporting countries. The best strategy to control TR4 is a multiple stakeholder approach which brings together governmental agents, NGOs, scientists and banana farmers to work on two aspects. One is the prevention and managing strategy: early warning system through diagnosis in areas where epidemics are occurring and (adjacent) areas where the pathogen is not yet found for surveillance, containment, eradication and exclusion of banana Fusarium wilt. In no infected areas, clean starting materials using tissue culture plants are highly recommended. In the nursery process fresh and TR4-free soil are absolutely needed in order to prevent to infect banana seedling before planting. For infected areas, containment measurements are also very useful for slowing down spreading of TR4. The second path is support of research, to development resistant cultivars by conventional somaclonal selection or molecular breeding, cultivar substitution, verifying the effect of cultivar mixtures/intercropping system, e.g., cover plant, crop rotation, ecological intensification, and screening and identifying beneficial microbiomes in suppressive soil. Comprehensive approaches combined with TR4 evaluation, utilization from local accessions and breeding new varieties adapting to local ecological conditions will be the future direction to combat TR4. Biological control of banana fusarium wilt receives increasing attentions for its sustainable production. We proposed a tritrophic biocontrol interaction relationship of bacteria-pathogens-bananas. The colonization of biocontrol bacteria in banana roots will be key factor for effective suppression of pathogens. Laser Scanning Confocal Microscopy and new developed molecular techniques could be used to monitor RFP-labelled bacteria exhibit chemotaxis towards green fluorescent protein (GFP)-labelled TR4 hyphae in banana plants. In conclude, we can provide a new theory for the interaction between the biocontrol bacteria, TR4 and banana plants, and provides new ideas for the biological prevention at early stage in nursey and control of banana wilt for sustainable production.
Biography: Sijun Zheng, Pathology scientist working at Alliance of Bioversity and CIAT/Yunnan Academy of Agricultural Sciences. Mainly work on the use of agrobiodiversity for sustainable agricultural production system with focus on the Greater Mekong Subregion and China; evaluation, screening and utilization of banana germplasm for Fusarium resistance and unravelling its underlying mechanism of resistance both in aboveground and belowground. Recent research outputs have been published in eLife, Frontiers in Plant Science, Frontiers in Microbiology, Journal of Fungi, etc.