Abstract
A rice cultivar 'Akino-uta' bred in Shiga Prefecture Agricultural Technology Promotion Center, is sensitive to panicle blast. To develop an Akino-uta near-isogenic line harboring the panicle blast Pb1, we investigated the applicability of three molecular markers, B1, B2 and B4, which are linked to Pb1, to 'Akino-uta'. As a result, the genotype of 'Akino-uta' using these molecular markers was the Modan-type (Pb1 harboring-type), which did not correspond with the panicle blast-susceptive phenotype of 'Akino-uta'. In this study, we sequenced a neighboring region of Pb1 from 'Akino-uta' and 'Koshihikari Aichi SBL' harboring Pb1 gene. Comparison of the sequences revealed that the reactivity of these molecular markers to 'Akino-uta' was caused by the sequence homology in both cultivars. Moreover, we analyzed genotype of 'Akino-uta' with PCR-marker, N3-2, which is linked by 0.0cM to Pb1 gene. Consequently, 'Akino-uta' did not harbor Pb1 gene. This case is the first report of molecular markers for selection of the Pb1 gene in japonica rice cultivar. When the genotype is of the Modan-type using molecular markers, B1, B2 and B4, in japonica rice cultivar, we should consider using other markers, N3-2 and so on, with them.
