Grouping of Soybean Varieties on the Basis of Seed Number·100-Seed Weight Ratio

[摘要] This investigation has been carried out to group soybean varieties into several types by yield components and to characteraize these types as to plant type and growth habit. Out of one hundred three varieties, collected from western part of Japan and examined, data of 84 varieties which yielding more than 200g/m2 were analyzed. And the following informations were obtained. 1) Soybean varieties were grouped into five types (Grain-Number type, Semi Grain-Number type, Medium type, Semi Grain-Size type, Grain-Size type) on the basis of Seed Number·100-Seed Weight ratio. Grain-Number (GN) type has the largest Seed Number·100-Seed Weight ratio and Grain-Size (GS) type has the smallest one. 2) GN type included more blanched type and blanch-spreaded type, based on the plant type classification suggested by WATANABE et al.14) in 1975. 3) GN type had longer vegetative period, whereas GS type had longer reproductive period. 4) On growth habits, GN type had more vigorous both vegetative and reproductive growth than GS type, and GN type had more vigourous growth of branches. 5) GN type was supposed to be advantageous under favourable conditions and GS type vice versa. 6) Recent soybean breeding in Japan seems to give too much weight to seed size. It might be necessary to consider balance of seed number and seed size.

[学科分类] 农业科学（综合）