This experiment is conducted in the Research Station, Abu-Ghraib , directorate of Agricultural Research , Ministry of Agriculture during the Autumn season of 2013, to investigate the effect of P fertilizer , bio fertilizer, humic acid and their interaction on the availability of, P and Fe, in the soil, their uptake, on yield and some yield components of corn(Zea mays L).
The RCBD has been adapted and each treatment has been replicated three times. The experiment treatments are two levels of P fertilizer, P0 (without adding P fertilizer), P1 (adding 30 kg P. ha-1), three levels of humic acid, H0 (without
adding humic acid), H1 (adding 20 kg H.A ha-1), H2 (adding 40 kg H.A. ha-1), and B0 (without inoculation of seed), B1 (inolculating seed with Bacillus), B2 (inoculating seed with Pseudomonas bacteria). P fertilizer and humic acid treatments are added and mixed with soil surface (10-15 cm). All experiment units have received 240 kg N ha-1 and 120 kg K ha -1 in three doses during the plant growth. Inoculated and other corn seed are planted in 10-7-2013 in plots of (3x3) m2 with distance between plants 0.25 and between lines 0.75 forming 4 lines and plant population 48 plant plot-1. The results can be summarized as follows:
In the field experiment, the main effects of P fertilizer, biofertilizer and humic acid are significant in increasing the availability of P and Fe in soil and eventually increasing their uptake by corn plant. However, more significant increases are associated with all possible interactions of these factors.
The highest availability of P, in soil is obtained at the interaction treatment of P1B1H2, and Fe at the interaction treatment P1B2H2 at both silking and harvesting stages of corn.