Comparative Study of Crop Water Requirement of Traditional and Hybrid Sorghum Varieties

An experiment was conducted to compare the crop water requirement of traditional and hybrid sorghum varieties at University of Agriculture Peshawar research farm. Soil moisture samples were collected to calculate Actual evapotranspiration for each variety. Maximum actual evapotranspiration of hybrid variety at full irrigation was 52% more than traditional variety at rainfed conditions (with pre irrigation). The crop coefficient (K c ) for different stages of V 1 I o , V 2 Io, V 1 I 1 , V 2 I 1 , V 1 I 2 and V 2 I 2 ranged from 0.24-0.55, 0.27-0.61, 0.49-0.86, 0.47-0.92, 0.37-0.88 and 0.39-1.00 to respective values of FAO ranging from 0.35-1.1. Both the local and hybrid varieties are not significantly different from each other in terms of water productivity at all irrigation levels. Highest crop water productivity (0.61 kg m -3 ) was observed for V 2 I 1 and lowest (0.43 kg m -3 ) for V 1 I 0 . Yield of hybrid variety was 62% more than the lowest grain yield of traditional variety under rainfed condition. At the full irrigation for traditional variety this percentage reduces to 59%. The reduction is only due to change in variety. Maximum harvest index (21%) was recorded for V 2 I 1 and minimum (11%) for V 1 I o . Keywords: Crop water productivity, traditional and hybrid sorghum, soil moisture sampling, full Irrigation, evapotranspiration.