Efficient Anther Culture of F₁ Plants Derived from Koshihikari and its Related Cultivars in the Japonica Rice

Abstract

The efficiency of anther culture of Koshihikari and its related cultivars with high eating quality i.e., Hitomebore, Akitakomachi and Kinuhikari was improved by using DKN medium as basal medium in the three-step anther culture method. The anther culture efficiency of F₁ plants derived from crosses between these cultivars was also improved. In this culture method, a positive correlation was recognized between the anther culture efficiency and the coefficient of parentage of the donor plant to Koshihikari. Therefore, this method was an effective means for the anther culture of materials derived from crossings between cultivars related to Koshihikari. On the other hand, the results implied that F₁ pollen which has a definite genetic background was regenerated preferentially. To examine the segregation of characteristics both in the anther culture-derived population and F₂ population, two populations were produced from the F₁ plant derived from a cross between the long-culmed medium-ripening cultivar Koshihikari and short-culmed early-ripening cultivar Niigatawase. No significant differences were observed in the segregation of heading date or culm length between the two populations. It is cocluded that the anther culture method developed in this study is a useful tool for breeding of rice by using Koshihikari and its related cultivars as a crossing parent.