Agro-physiological studies on the yield performance of mungbean. I. Cultivaral differences in earliness in flowering and their relationships with growth and seed yield.

Abstract

The growth and field performance of 24 mungbean cultivars selected from initial 83 introductions based on 1987 trials, were evaluated in field experiments to identify the cultivars suited for cultivation in warm temperate environment and to examine the basis of high field. Relationships among earliness in flowering, growth and seed field were examined. The number of days to first flower (DFF) was positively correlated with plant height, number of primary branches, and vegetative, reproductive, and total main-stem nodes. However, DFF was negatively correlated with the percentage of reproductive nodes to total number of main-stem nodes, number of days to first muture pod, reproductive stage duration, and seed yield. Thus, the early flowering cultivars had limited vegetative growth, but had a long reproductive growth duration and produced high seed yield. Late flowering cultivars had significantly more vegetative and reproductive main-stem nodes but very low seed field. Yield was ncgatively correlated with all vegetative parameters. However, some high yielders, including the top yielding KUS, the Indian origin check, had a high degree of vegetative growth. The generally lower yield of some cultivars in 1988 was partly due to the attack of spider mite (Tetranychus sp.). The KUS check cultivar which flowered relatively early, had a long reproductive growth duration, and the highest 2-year mean seed yield of 191 gm-2, appears to be the Ideo-type for warm temperate environments.