YIELD AND QUALITY OF SOYBEAN SEEDS OF HIGH AND LOW FORCE SUBMITTED TO WATER DEFICIT

This study aimed to evaluate the effect of the drought in the early vegetative stage on the yield and quality of soybean seeds, from seeds of high and low vigor. The study was conducted using the cultivar M-SOY 8008 RR. The experimental design was completely randomized in a 52 factorial, five periods of water deficit (10-10, 11-20, 21-30 and 31-40 days after emergence (DAE)) and two levels of seed vigor (high and low), for a total of 10 treatments with four replications. It was concluded that soybean plants grown from seeds of high vigor have increased plant height, stem diameter, apparent harvest index and biological yield, than plants originated from seeds of low vigor, providing up to 20% increase in productivity. The water deficit in the growing season, in soybeans, does not affect the height of first pod, number of nodes on main stem, number of pods with one and two seeds and seed yield per plant, but reduces plant height, stem diameter and number of pods with three seeds, both in plants grown from seeds of high and low vigor. However, water deficit after 20 DAE causes reduction of the physiological quality of soybean seeds, the reduction being more severe on plants from seeds of low vigor.