Effect of water stress on yield and yield components of mung bean at different grows (Vigna radiate L.)

In order to determine the best cultivars of Mung Bean (Vigna radiate) and the effects of drought stress on mung bean، a field experiment was conducted in a split-plot arrangement using randomized complete block design with three replication at Agricultural Research Station of Varamin in 2009 cropping season. The main plots included drought stress in different stage of growth (flowering، poding and grain paramation)، and sub plots included five cultivars (Partov، Gohar، NM-94، C-1-6-16، VC1973A). The results of the experiment showed that the effect of drought stress on traits such as grain yield، 100 grain weight، number of pod per plant، number of grain per pod، number of branch and plant height were significant. grain yield، 100 grain weight، number of pod per plant، number of grain per pod were significant between cultivars studying. The results of mean comparison analysis indicated that the highest of most characteristics obtained from drought stress at the grain paramation stage. Partov cultivar produced the highest grain yield، 100 grain weight، number of pod per plant، number of grain per pod. Also، in step by step regression analysis، 100 grain weight and pod weight associated by grain 59/2 percent portray changes of grain yield. Incommonly can be said، the most influence obtained from drought stress at flowering phase that the heighest of decreacing yield would be in phase. Partov cultivar and NM-94 show more resistance as compared with other cultivar in this study.