Selection for high palatability lines by amylose content adjusted by heading date for rice breeding.

摘要

Indirect selection via low amylose content for high palatability usually results in predominantly early-heading genotypes. To overcome this problem, a regression equation of milled rice amylose content on heading date was calculated. The residual (observed amylose content value - estimated value from the regression) + mean observed values was designated the adjusted amylose content value (AAC). Tests for 3 years revealed that AAC was significantly correlated with palatability (r = -0.439 to -0.589), showing that palatability and amylose content were correlated even among genotypes with the same heading date. Correlations between AAC and palatability in the following year were significant for 3 years (r = -0.417 to -0.479), showing that genotypes selected for low AAC had relatively high palatability in the following year. These results show that AAC can be used as a criterion for selecting highly-palatable genotypes with a wide range of heading dates. Similar results were obtained using brown riceamylose.