Effect of water deficit tension on yield and yield components of mung bean (Vigna radiata L.) in different planting densities

In order to investigate the effect of water deficit tension on yield and yield components of mung bean in different densities, a field experiment was conducted in Dezfoul area in summer 2010 as a split plot in a randomized complete block design with four replications. In this research, treatments of irrigation after 90, 120, 150 and 180 mm evaporation from class A pan evaporation in the main plots and the density as distances 6, 9, 12 and 15 cm between two plants on rows of planting in the subplots. The results of experiment showed that the effect of different irrigation levels was significant on number of pods per plant, 1000- grain weight, grain yield, biological yield and harvest index, but had no significant effect on number of grain per pod. It is inferred that the mung bean plant is very sensitive to water deficit tension and significantly yield loss is occurred due to increasing water tension. Treatment effect of density was significant on traits the number of pods per plant, grain yield, biological yield and harvest index. Based on these results, increase or decrease of density both were the limiting factors of yield. Also, the interaction of water deficit tension treatments and plant density except on the number of grain per pod had significant effect on all the traits. According to the evaluation results of this research, a distance of 12 cm between two plants on rows of planting as the best distance for optimum irrigation treatment (irrigation after 90 mm accumulative evaporation from evaporation pan class A) is recommended for maximum plant yield of mung bean in Dezfoul area.