تاثير تراكم بوته و مقادير نيتروژن بر ويژگي هاي مورفولوژيك و ميزان پروتيين دانه ذرت دانه اي

Effects of Plant Density and Nitrogen Rates on Morphological Characteristics and Kernel Protein Contents of Corn (Zea mays L.)

The effect of different plant density and nitrogen rates on morphological characteristics and protein contents of corn (Var. Sc704) was determined. The experiment was conducted as split - plot arranged in randomized complete block design with four replications in 1999 at Kushkak Agricultural Research Station, Shiraz University. The treatments composed of nitrogen at four rates (0, 80, 160, and 240 kgN/ ha) in main plots and plant density at four levels (6.0, 7.4, 8.8 and 10.2 plants/m2) in sub plots. The results showed that increasing N level did not significantly increase ear diameter and length at 80, 160 and 240 kg N/ha. Lowest ear diameter and length were obtained at lowest N level with a significant difference with other N levels. Number of ear per plant and plant height were not affected by N rates. Increasing N rates increased stem diameter and ear height with no significant difference between N levels. Increasing plant density decreased ear diameter, as well as length and stem diameter but ear height, number of ear per plant, and plant height were not affected by plant density. Increasing N rates, increased kernel protein content with no significant difference between 160 and 240 kgN/ha. Increasing plant density decreased kernel protein content. The highest kernel protein content (9.2%) was obtained from an interaction of the highest N level and the lowest plant density.