Abstract
Characteristics of flowering, and pod and seed developments of phasey bean, Macroptilium lathyroides L. URB., were investigated under the field condition. Sowing was done on May 15 in rows 60 cm apart. The number of mature plants was 25 plants per 1 m row length. Flowers were distinguished by five days interval by painting a color on a calyx. Plants were cut and pods were harvested on Aug. 3, 8, 13 and 19. On each harvest, pods were assorted according to the flowering dates. Flowering first occurred on July 18 (65 days after seeding) and increased in number from July 29 till Aug. 4 with the peak on Aug. 1. The proportion of the number of pods originated in this vigorous flowering stage (full-bloom stage) in the total pods at each harvest date was 56-68%. Above 90% of seed germination was attained on the 9th day after flowering and seed weight reached the average ripe seed weight (7.86 g of thousand kernel weight) on the 12th day after flowering. Meanwhile, pod color turned black on the 10th day after flowering, which was a sign of near ripe seed. The pods began to shatter on the 16-17th day after flowering. The total seed yield, germinable seed yield and the yield of seeds in a black pod were the highest in Aug. 19 harvest. The proposed timing of seed harvest for phasey bean was as follows : Harvesting seed should be done after black coloring of all the pods originated in full-bloom stage (the 10th day after the end of full-bloom stage) and before the initiation of shattering of the pods (the 16th day after flowering) originated on the peak date of anthesis (Aug. 1). Consequently the optimum period for the conventional seed harvest by the cutting of plants or peduncles at one time was found to be Aug. 14-17 in this experimental condition.
