2006 Volume 75 Issue 2 Pages 153-158
To understand the genetic diversity of rice cultivars and to establish a breeding system to accumulate superior traits, we performed pedigree analysis of the varieties bred for over 80 years in Hokuriku National Agricultural Experiment Station(143 varieties). The total number of ancestors increased from 1980s and doubled during the last 10 years, and the number of lines in the yield test was 1122. The Hokuriku lines had only a few ancestors. The average of the coefficient of parentage between Koshihikari and the 16 Hokuriku Lines used for the yield test was 0.463. The coefficients of parentage between Koshihikari and these 16 Hokuriku Lines were not significantly correlated with eating quality. Since 86% of the breeding lines in the yield test (44 lines) were progeny of Kinuhikari, Kinuhikari descended from Koshihikari was considered to have contributed to improvement of eating quality in rice breeding.
