Influence of Gamma Irradiation and Nitrogen Fertilization Levels on Growth and Yield of Maize (Zea mays L.) Grown on Sandy Soil

Abstract

A field experiment was carried out on sand soil using maize as a test crop exposed to different rates of N fertilizer and doses of gamma radiation. Response of maize to these exogenous factors was evaluated. Results revealed that, the irradiated (20 Gry) plants have higher grains (5.4 ton ha-1) and lower stalks yield (17.533 ton ha-1) than those of the non-irradiated plants (5.111 ton ha-1 and 18.867 ton ha-1, respectively) fertilized with rate of 240 kg N ha-1. In this respect, the relative increase or decrease was 5% and -7% over or lower the non-irradiated one, for the same sequence. Increasing gamma rays dose up to 40 Gry achieved higher grains and stalks yield (5.533 ton ha-1 and 18.778 ton ha-1, respectively) than those recorded with the non-irradiated plants (5.111 ton ha-1 and 18.867 ton ha-1, respectively) fertilized with rate of 240 kg ha-1. Relatively, grains were approximately increased by about 7% over the non-irradiated plants while stalks yield was lowered by about 0.5%. It means that irradiation did not significantly, positively or negatively, affected the grain and/or stalks yield. Grain and stalks yields were highly significantly increased by increasing the N fertilizer levels as compared to the non-fertilized control.