Effect of cycocel on nitrate reductase activity and grain yield in mungbean (Vigna radiata L; Wilczek)

Two mungbean (Vigna radiata L; Wilczek) varieties viz. Pusa Baisakhi and S-8 differing in biomass and grain yield, and duration of maturity were sprayed with 500 ppm cycocel at the beginning of flowering to study the effect on yield parameters and nitrate reductase activity (NRA). The grain yield of the high yielding variety S-8 increased by cycocel treatment due to increase in pod and seed number. Further it showed a higher NR activity also in the leaves as compared to Pusa Baisakhi, while the latter variety had higher NRA in the nodules. It was concluded that lower biomass and grain yield of Pusa Baisakhi was related to lower NR activity and the improvement in yield in S-8 by cycocel treatment was because of greater allocation of biomass to the grains.