雄性不姙 Burley 種 담배에 있어서 二面交配에 依한 量的形質의 遺伝分析

Diallel Cross Analysis of Quantitative Characters in Male - Sterile Burley Tobacco (Nicotiana tabacum L.)

To obtain basic information for the burley tobacco breeding, a partial diallel set (including the F₁) of four cytoplasmic male sterile parents and their male fertile varieties were grown in a randomized block design with 2 replications. The percent of heterosis and specific combining ability, degree and direction of dominance were evaluated. Positive or negative heterosis and heterobeltiosis were observed in each character depending upon F₁ combinations. Average percent of heterosis for plant height, yield, and total alkaloids were shown io positive value, while clays to flowering and number of leaves per plant were shown negative. Average heterobeltiosis for yield was shown in positive value and other characters were shown in negative values. In analysis of combility, GCA was greater than SCA in five characters. L-8 expressed high negative GCA effect in plant height, number of leaves per plant and yield. The highest positive SCA effects were expressed in MS Burley 21×L-8 and MS Burley 37 × L-8 crosses for plant height, days to flowering and yield. Yield exhibited overdominance and other characters showed partial dominance. More dominant alleles were present than recessive, indicated by positive F values. The direction of dominance in plant height, yield, and total alkaloid were positive, and that of days to flewer and number of leaves per plant negative.