THE EFFECT OF DROUGHT STRESS ON THE GROWTH AND YIELD OF SOYBEAN (GLYCINE MAX L.)

Drought stress affects the growth and yield of soybean. Stunted growth will have an impact on yield. This study aims to determine the effect of drought stress on the growth characteristics and grain yield of soybean. This research uses a randomized complete block design (RCBD) and three replications. The first factor was soil moisture content consisting of four levels, i.e., 100%, 75%, 50%, and 25% field capacity. The second factor was the growth stage consisting of three kinds, i.e., the vegetative active, flowering, and seed filling stages. The results showed that soil moisture content below 75% field capacity reduced the leaf area index (LAI), leaf area duration (LAD), specific leaf area (SLA), net assimilation rate (NAR), crop growth rate (CGR), the seed weight per 100 seeds, and the weight of the seeds per plant. In seed filling stage is more sensitive to water shortages than the vegetative or flowering stages. At all stages of growth, a higher drought level equals a higher decrease in the soybean growth and yield. For future research, we suggest that soybean planting utilize 100% field capacity.