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Poster: Biology & Disease Mgmt: Genetics of Resistance


Exploring gene loci controlling bakanae disease resistance by genome-wide association mapping
S. CHEN (1), K. Huang (2), Y. Kuo (2), M. Lai (3), D. Wu (3), C. Chung (1) (1) Department of Plant Pathology and Microbiology, National Taiwan University, Taiwan; (2) Department of Bio-Industrial Mechatronics Engineering, National Taiwan University, Taiwa

Bakanae disease, caused by Fusarium fujikuroi, is a rice seed-borne disease and widely distributed in rice growing areas. Infected rice seedlings may show complex symptoms including abnormal elongation of stem or internodes, wider leaf angle, slenderness, and even die, causing considerable yield and quality loss. In recent years, studies have reported the rising incidence and severity of the disease in Asia. Even though the disease has been known over a century, little is known about the resistance genetics and resources in rice. In this study, we used genome-wide association mapping approach to identify gene loci controlling bakanae disease resistance. A set of 413 diverse rice varieties from 82 countries (rice diversity panel; containing 44,100 SNPs available from open-source) was artificially inoculated and disease levels were evaluated by visual observation using a 0-3 rating scale, detailed image analysis using a newly developed MATLAB-based software and quantification of F. fujikuroi colonization in rice seedlings with a selective medium. A total of 24 QTLs associated with disease severity and/or pathogen colonization were mapped by the mixed linear model in TASSEL software. Defense- and hormone-related candidate genes identified within the QTLs will be further validated.