Effects of Water Deficit During Reproductive Stage on Growth and Yield of Soybean

Abstract

The response of four soybean [Glycine max (L.) Merrill] varieties; SJ.2, SJ.4, #75 and AGS292 to drought stress imposed at 3, 5, 7 and 9 days during reproductive stages (R1-R2) was under investigation during November 2008 to February 2009 at Mae Hea Agriculture Research and Training Center, Faculty of Agriculture, Chiang Mai University. It was found that increase the duration of water deficits from 3, 5, 7 and 9 days during the reproductive stage (R1-R2) had reduced the total dry matter accumulation, crop growth rate (CGR), pod growth rate (PGR), partitioning coefficient of photosynthate to the pod, seed yield, 100 seed weight, pod dry matter, pod per plant and seed per pod of all varieties. AGS292 (vegetable soybean type) performed well under long duration of water deficit (9 days), followed by SJ.2, SJ.4 (grain type) and #75 (vegetable soybean type)