AGRO.PHYSIOLOGICAL RESPONSE OF SOYBEAN TO SPATIAL ARRANGEMENT AND IRRIGATION REGIMES

Field trials were conducted during the years 1990-1993 at the Agriculture Research Institute, Tandojam. The spatial arrangements comprised 45x5, 45x10, 60x5 and 60x10 cm and irrigation regimes were 3, 4, 5, and 6 applied at various developmental stages. Six irrigations, applied at various growth stages (25 days of sowing, bud formation, flowering, pod initiation, seed formation and complete pod filling) resulted in significantly higher seed index, seed yield per hectare, seed oil content and dry matter accumulation. Planting patterns differed significantly for seed yield, seed index, oil content and dry matter accumulation. Although increasing inter -and intra-row spacing increased seed index and seed oil content but reduced seed yield and dry matter accumulation. Differences in seed index, seed yield per hectare and dry matter accumulation over the season were significant, whereas no significant differences in oil content were found. It is suggested that for getting better seed yield, oil content, dry matter accumulation, soybean should preferably be sown in the pattern of45x10 cm and applied six irrigations.