Effects of some plant growth regulators and nutrient complexes on above-ground biomass and seed yield of soybean grown under heat-stressed environment

Abstract

A two-year study was conducted to determine the effects of some Plant Growth Regulators (PGRs) and nutrient complexes on biomass weight, seed yield and yield components of both main and double cropped soybean grown under hot and dry conditions. The experimental design was Randomized Complete Block with four replications. Atonik, Biomaster, GA3, Kinetic, Maxicrop, Cytozyme and Megahix were used as plant growth regulators. The soybean cultivar was A3935 (MG III). Application of PGRs had different effects on biomass weight, seed yield and yield components of both main and double cropped soybean. The highest biomass weight (1054.0 g-2) was obtained from Maxicrop and the lowest (891.8 g-2) was obtained from Megahix applied plots in main cropped soybean. Under double crop conditions, however, the highest biomass weight (857.6 g-2) was obtained from Cytozyme and the lowest (780.0 g -2) was obtained from control. Application of PGRs increased the seed yield and yield components of soybean under both main and double cropped conditions. The highest seed yield was obtained from Atonik with 3876 kg ha -1 for main crop soybean and 3447 kg ha-1 for double cropped soybean. The lowest seed yields were obtained from no chemical applied control plots of both main and double cropped soybean with 3386 and 2838 kg ha-1, respectively. Application of Atonik, Cytozyme and Maxicrop could be suggested to alleviate heat stress and increase seed yield of both main and double cropped soybean grown under hot and dry conditions. © 2006 Asian Network for Scientific Information