Response of Two Sorghum Bicolor (L.) Cultivars to Potassium fertilizer and Distance Between Rows


A field experiment was carried out in clay loam soil during spring and autumn seasons , 2008 to study three levels of K fertilizer ( 0 , 70 and 140 Kg / ha ) and three distances between raws ( 50 , 60 and 70 cm ) on growth and yield of two sorghum cultivars (Ankath and Rabih). A split–split plots design was used according to R.C.B.D. with three replicates. Cultivars was assigned as main plots and plant distance as sup plots , while the sub–sub plots were K fertilizer levels. Results showed a significant difference between the two cultivars in a day from sowing to 50% of flowering , leaf area , leaf area index, 500 grains weight, grains no. head-1 and harvest index . increased rows distance from 50 to 70 cm causedearliness of flowering , increased leaf area at in monsoon, leaf K% , grain no. head-1 , 500 grain weight and harvest index (24.56 , 30. 28%) for each season. 50 cm was superior in leaf area index , biological yield and grain yield(7.19 , 10.52 t.ha-1) for each season respectively. Increase of potassium level lead to be earlier flowering and significant increase in all agronomic and yield traits . The potassium level of 140 kg.ha-1 gave the highest grain yield and harvest index of 6.88 and 10.32 t.ha-1 , and 24.47 and 31.11%, for each season respectively. It could be concluded that grain yield could be increased by using the distance that applied in Iraqi agronomy of 20 X 70 cm, where as, the increase about it 25.92 and30.68% , for each season respectively. Land, production, water management and reduced weeds growth , also could be used , if this distance properly applied.