벼 組織培養을 利用한 突然變異誘發 硏究 Ⅰ. 半數體에 대한 化學物質의 突然變異 誘起效果

In vitro culture techniques for mutation breeding in rice Ⅰ. Effect of chemical mutagens on haploid derived from anther culture

This experiment was conducted to broaden the scope of mutation breeding and to introduce new source of variation by in vitro technology. Node tissue of haploid plants, derived from rice anther culture (CV. Dashukei 2) were cultured on the N6-Y1 basic medium supplemented with 10⁻⁵M NAA, 0.5 x 10⁻⁵M kinetin, and 5x10⁻⁵M ABA. Chemical mutagens, DES, EMS, Sodium Azide, and MNNG were applied in vitro system through this experiment. Diploidization of’haploid plants regenerated from node culture with mutagens were conducted. The progeny of regenerated diploid plants, M₂ generation, were evaluated in their major agronomic characters, and they were compared with A₂ generation derived from anther culture. Haploid plants directly regenerated from node tissue of haploid without callus formation. The ratio of plant regeneration was decreased when the concentration of chemical mutagens were increased. Autodiploidization ratio by tiller separation was 3.1% while that of 0.2% colchicine treatment for 12 hours was 23.0% under the field condition. Phenotypic patterns of 197 M₂ lines derived from node culture with mutagens showed that 80.2% M₂ lines were similar to their parental variety, but the others were different in some characters. For days to heading and culm length the means did not change but the range of variance was larger in M₂ lines than in parental variety. Distribution of days to heading in 146 M₂ lines derived from DES treatmat was similar to 137 A₂ lines derived from anter culture, but that of culm length between two populations showed a significant difference.