Seed and Oil Productivity upon Foliar Spray of Soybean (glycine max l.) with Humic and Ascorbic Acids with or without Seed Irradiation

THE STUDY evaluates the beneficial effects of soybean foliar ……..spray with humic acid (HA) and ascorbic acid (AA) antioxidants at 2000 mg L^-1 HA and 300 and 600 mg L.^-1 AA; and seed irradiation of 15 and 30Gy gamma rays. The split-plot experiment was conducted on a sandy soil in Ismailia Governorate, Egypt, during 2010 summer season. Main plots were for foliar spray treatments of: none, HA, AA1, AA2," HA+AA1"," HA+AA2"; AA1 and AA2, i.e. 300 and 600 mg L^-1. Sub-plots were for irradiation of, none, 15Gy and 30Gy. 100-seed weight, straw and pod yields as well as protein, N, P, K and oil contents; protein and oil yields and N, P and K uptake increased by 15Gy than by 30Gy. Main effect of spray shows a general descending order of "HA+AA2" > "HA+AA1" > HA > AA2 > AA1. Highest straw yield (5.82 Mg ha^–1) was by HA+AA1+15Gy. Highest seed yield (2.99 Mg ha^–1) was by HA+AA2+30Gy. Highest uptake of P (23.2 kg ha^–1) and K (206 kg ha^–1), respectively at straw were achieved owing to the addition of HA+AA1+15Gy gamma ray while treatment of HA+AA2 with 15Gy gamma ray gave highest N-uptake (163 kg ha^–1). Highest N, P and K uptake in seeds (149, 19.1 and 49.0 kg ha^–1, respectively) were by (HA+AA2+15Gy gamma ray dose). The treatment of HA+AA2 with 15Gy gamma ray was superior to the other treatments.