Abstract
The relationships among branching habit, yield components, and grain yield of 37 strains of white azuki bean (Vigna angularis), collected from various parts of Akita Prefecture, were studied in field experiments in 1990 to investigate the relationship between branching habit and yield. Grain yield/plant, number of nodes/plant, number of pods/plant, and number of grains/plant significantly differed among strains, but differences were more closely associated with morphological characteristics of branch portions rather than those of the main stem. The number of branches was also significantly different among strains. Grain yield/plant was highly positively correlated with the number of pods/node and the number of grains/pod on both the main stem and branch portions, but was only slightly correlated with 100-grain weight. Correlations between the number of branches to the yield components on the main stem and branches were generally not significant, except for 100-grain weight of main stem which was slightly negative. The ratio of branch grain size (100-grain weight) to main stem grain size tended to be higher in strains having greater branch numbers. From these results, it was estimated that differences among strains in yield components were not attributed to differences in branching habit, although yielding ability was highly correlated with the branch yield components.
