Abstract
A pot experiment was conducted to determine the effect of gypsum content in soil and level of phosphate (P) fertilization on growth and yield of corn. A factorial experiment was carried out with two factors the first was three different percent- tages of gypsum (4.6, 14.8, and 24.4 %) and the second was five levels of phosphate fertilization (0, 40, 80, 120, and 160 kg P ha-1) in four replicates with RCBD. Corn seeds were grown in plastic pots. Nitrogen was applied as urea at a rate 320 kg N ha-1 in two doses, while potassium was applied in one dose as K2SO4 at a rate reached 71 kg K ha-1. The experiment was continued for 60 days. A first cut was taken 40 days after cropping to calculate Absolute Growth Rate (AGR). After terminating the experiment, plant height was measured then plants were cut near soil surface, dried and dry weight was measured and P content in plant was determined to calculate P uptake. Roots were extracted from soil, dried and dry weight was measured. Results revealed that 14.8 % gypsum content was significantly superior in AGR (0.495 g plant -1 day-1), plant dry weight (16.96 g pot-1), root dry weight (22.03 g pot-1), and P uptake (5.10 mg P pot-1). Gypsum content 24.8% was significantly superior in plant height (35.40 cm plant-1). Fertilizer level 160 kg P ha-1 achieved the highest significant value of AGR (0.438 g plant-1 day-1). While the superiority was significant for the fertilizer level 120 (kg P ha-1) in plant height (34.11 cm plant-1), plant dry weight (14.18 g pot-1), root dry weight (17.58 g pot-1) and P uptake (5.67 mg P pot-1).