QTL Analysis Revealed One Major Genetic Factor Inhibiting Lesion Elongation by Bacterial Blight ( pv. ) from a Cultivar Koshihikari in Rice.

pv. () is a pathogen that has ravaged the rice industry as the causal agent of bacterial blight (BB) diseases in rice. Koshihikari (KO), an elite cultivar, and ARC7013 (AR), an cultivar, are both susceptible to . Their phenotypic characteristics reveal that KO has shorter lesion length than that of AR. The F population from KO × AR results in continuous distribution of lesion length by inoculation of an race (T7147). Consequently, quantitative trait loci (QTL) mapping of the F population is conducted, covering 12 chromosomes with 107 simple sequence repeat (SSR) and insertion/deletion (InDel) genetic markers. Three QTLs are identified on chromosomes 2, 5, and 10. Of them, has the strongest resistance variance effect of 20.5%, whereas and have minor QTL effects on resistance variance, with 3.9% and 2.3%, respectively, for a total resistance variance of 26.7%. The QTLs we examine for this study differ from the loci of BB resistance genes from earlier studies. Our results can help to facilitate understanding of genetic and morphological fundamentals for use in rice breeding programs that are more durable against evolving pathogens and uncertain climatic temperature.