Evaluation the Effects of Biological Fertilizer on Physiological Characteristic and Yield and its Components of Corn (Zea mays L.) Under Drought Stress

Problem statement: This experiment was carried out for study the effects of chemical and biological fertilizers and interaction between them on some physiological characteristic and yield and its components of seed corn in two different irrigation. Approach: The experiment was conducted in a split plot factorial with completely randomized block design using four replications. Sub plots consisted of combined application levels N-fertilizer with two level (0 and 300 kg.ha^-1) Urea and two level of biological fertilizer (0 and 4 L.ha^-1) in four stage that was from 4th leaf appearance until milk stage. Biological fertilizer was combined of Kadostim, Phosphotern, Aminolephorte and Hyomiphorte. Main plots consisted of two period of irrigation (8 and 12 days). Results: The results showed that highest grain yield was in conditional application at integrated treatment 300 kg.ha^-1 Urea fertilizer and 4 L.ha^-1 biological fertilizer (12.5 ton.ha^-1) that with compared to control treatment showed increase 257%. In this treatment decrease irrigation (12 days period of irrigation) from pollination stage to seed maturity, decreased 8.9% in yield. The highest kernel number per ear and highest 1000 kernel weight was in integrated fertilizer treatment but in 8 days period of irrigation was not significant difference between integrated treatment and chemical treatment for 1000 kernel weight. The integrated treatment in 8 days period of irrigation showed the highest CGR, NAR and LAI (14.2 g.m^-2.day^-1, 2.9 g.m_LA^-2.day^-1 and 5.1) respectively. And decrease 12 days period of irrigation had little effect on CGR and NAR but application of chemical fertilizer after decrease irrigation CGR had much reduce trend to compared integrated treatment. Conclusion: In conclusion for reach to high yield in corn biological fertilizer can not sufficient but integrated application of fertilizers (biological and chemical fertilizers) became causes significant increase in yield.