Effect of Potassium Fertilizer Levels and Plant Density in Growth and yield in two Corn varieties (Zea mays L.)

Abstract

A field experiment was conducted in Clay Loam soil at field crop Research station of state Board of Agricultural Abu-Ghraib , during spring and fall seasons of 2011. To study the effect of Potassium fertilizer levels and Plant density on growth characterize, grain yield and yield components of two Corn varieties. A split-split plot arrangement was used according to R.C.B.D. with three replicates. Varieties (synthetic 5018 and IPA 5012) were assigned in the main plots, three levels of potassium fertilizer (0 , 125 and 250 Kg K. ha-1) in the sub plots and plant population (44444 , 66666 and 133333) plant. ha-1, in the sub-sub plots. The results showed that the two varieties were significant differences in tasseling, silking, plant height, ear height, no. of grains per ear, 500 grain weight, total yield and protein percentage in grain in two seasons. Syn. 5018 hold significant superior in tassiling, silking, plant height, ear height, No. of grain per ear and total yield (9.34 and 10.39) Ton. ha-1 in spring and fall season respectively. While Syn. 5012 significantly superior in 500 grain weight and protein percentage in grain in both seasons. The level K3 (250 Kg K. ha-1) achieved significant superiority in the plant height, ear height, leaf area, No. of ear per plant, No. of grain per ear, 500 grain weight, biological yield, total yield (11.41 and 12.90) Ton. ha-1,and harvest index (51.68 and 53.55)%, concentration of K in plant (1.86 and 1.85)% and in grains (0.325%) and protein percentage in grains (10.01 and 9.81)% in spring and fall season respectively. Increasing plant density from (44444 – 133333) plant. ha-1 delayed no of days to 75% tassiling and silking, and decreasing leaf area, No. of ears per plant, no. of grains per ear, 500 grain weight, harvest index, concentration of K in plant and grains and protein percentage in grains, and increasing plant height, ear 114 height, leaf area index, biological yield and total grain yield (11.55 and 12.66) Ton. ha-1 in spring and fall season respectively. The interaction between varieties and potassium levels significantly affected in some traits the combination of the treatment (Syn 5018 × 250 Kg K. ha-1) was superior significantly on other combination and gave higher mean to the ear height and for total grain yield (11.80 and 13.85) Ton. ha-1 in spring and fall seasons respectively. Also, the interaction between varieties and plant density significantly affected in No. of grain per ear and 500 grain weight in two seasons the combination of (Syn 5018 with the (D3 plant. ha-1) gave higher mean for biological yield (28.69 Ton. ha-1) and for total yield (13.74 Ton. ha-1) in fall season. While the combination of (Syn 5018 with the D1 P. ha-1) gave higher mean for leaf area (5955), harvest index (52.5%) in fall season. The combination of (250 Kg K. ha-1 and D3 plant. ha-1) was superior significantly on other combinations in means of silking, plant height, leaf area index, biological yield (29.95 and 31.69) ton. ha-1, while the combination of K3 (250 Kg K. ha-1 and D1 plant. ha-1) gave higher mean for leaf area, no. of ears per plant, no. of grain per ear, 500 grain weight, harvest index, and concentration of K in grain in booth seasons. Three-way interaction between varieties, potassium levels and plant densities significantly affected in silking and total grain yield in both seasons and for plant height, protein percentage in grains in fall season. The combination of Syn. 5018 + D3 P. ha-1 + 250 Kg K. ha-1) gave heigher mean for total grain yield (14.19 and 15.35) ton. ha-1 in spring and fall season respectively.