Abstract
In order to identify genes for field resistance to rice blast in the upland rice variety Sensho, analysis of quantitative trait loci (QTLs) was performed by using F2 plants/F3 lines derived from a cross between Sensho and a paddy rice cultivar Norin 29. Resistance to rice leaf blast was measured at an upland nursery. The disease severity was scored by visual observation. Continuous variations were observed and it was suggested that several genes were involved in the resistance to leaf blast in Sensho. Four QTLs were detected in the vicinity of restriction fragment length polymorphism (RFLP) markers G271 (chromosome 4), G177 (chromosome 4), C1172 (chromosome 11) and S826 (chromosome 12), respectively. QTLs near RFLP markers G271, G177, C1172 and S826, explained about 45%, 13%, 8% and 8% of the phenotypic variation in the F3 lines, respectively. For all of the QTLs, alleles from Sensho increased the score of resistance to rice leaf blast.
