Effect of Paclobutrazol on Yield and Seed Quality of Mungbean (Vigna radiata L. Wilczek)

Abstract

The effect of paclobutrazol (PP333) on seed yield and quality was studied in 4 mungbean varieties, i.e. Uthong 1, KPS 1, KPS 2 and CN-60 in rainy season, 1989, at Kasetsart University, Kamphaengsaen Campus. Paclobutrazol at the rate of 120 g.ai/500 litre of water/rai ( 750 g.ai/hectare ) was directly sprinkled onto mungbean plants at 45 days after planting (DAP) which was at 8, 11, 8 and 10 days after first flowering of Uthong 1, KPS 1, KPS 2 and CN-60, respectively . Factorial in RCB with 3 replicates was employed in this study. The results showed that pod number per plant and seed yield ( kg/rai ) were significantly increased by paclobutrazol ( 23 and 16% over the control, respectively ). Paclobutrazol had no effect on node number and branch number per plant in mungbean, although there was a tendency in reducing plant height at harvest. Paclobutrazol tended to delay leaf senescence and seed desiccation during plant maturation while seed germination was not affected by paclobutrazol. Among the 4 mungbean varieties, KPS 1 showed higher pod number per plant while Uthong 1 demonstrated a greater vegetative growth than the other 3 varieties. However, there was no significant differences between varieties in terms of seed yield. KPS 2 produced the highest quality seed in this study.