4903
Osama Moawad Moawad Dewedar
DETERMINATION OF CROP COEFFICIENT AND WATER REQUIREMENTS FOR BEAN CROP UNDER DRIP IRRIGATION SYSTEM
Phaseolus vulgaris, water application, surface drip irrigation, subsurface drip irrigation, yield and quality, crop coefficient, evapotranspiration, available water, salt accumulation and soil moisture.
Field experiments were carried out during two consecutive seasons of (2012 and 2013), at Shlakan Experimental Farm of the Faculty of Agriculture, Ain Shams University, Kalubia Governorate, Egypt. The experimental site represents the old alluvial soil of the Nile Delta. The soil was clay loam in texture.The main objective of this study was to determine the values of bean crop coefficients along the growing season through the actual measured evapotranspiration in the field and the calculated evapotranspiration by the modified Penman- Monteith (FAO-56). The study also aimed to determine the water use efficiency of bean crop (Phaseolus vulgaris L.) varieties Contender and Bronco under Egyptian conditions in case of using surface drip irrigation (SDI) and subsurface drip irrigation (SSDI). The crop coefficient was calculated during the growing season for each treatment and reaching to the length of the different stages of bean in each treatment.Crop coefficient ranged between (0.63- 0.64) for initial, (0.87 - 0.82) for development, (0.99 - 1.09) for midseason and (0.80-0.95) for harvesting stage in case of Bronco variety with both irrigation system and three levels of water application. While ranged between (0.59- 0.61) for initial, (0.78 - 0.98) for development, (1.07 - 1.19) for midseason and (0.73-0.88) for harvesting stage in case of Contender variety with both irrigation system and three levels of water application . The higher values of (Ecsw) were (3.66 ds/m) and (1.55 ds/m) at 10 cm with irrigation at 40% of available water for surface drip irrigation system and sub surface drip irrigation system respectively. Results exhibited that, irrigation at 80% of available water (A.W) increased significantly vegetative growth (plant height, branches no., leaves area, and pods no. as well as dry matter of stems, leaves, pods, roots and total plant and green pods yields kg/fed). Pod length exhibited its highest significant value when plants were subjected to (80% A.W). While, irrigation at 60 or 40%of available water (A.W) resulted the lowest values of the growth parameters of bean crop plants. Generally, subsurface drip irrigation (SSDI) with 80% of available water (A.W) increased significantly vegetative growth, yield and pods quality as well as dry matter of stem, leaves, roots, pods and total plant. It could be concluded that in both bean varieties, the interaction influence was significant on green pods yield kg/fed., whereas pod weight was not significantly affected by the interaction for the two varieties. A similar trend of the interaction in both varieties was obtained in pod quality indicating that those parameters reached to their highest significant value when bean plants were irrigated by subsurface drip irrigation system (SSDI) at 80 % of available water. Moreover, the above mentioned characters showed their lowest interaction values parameters and gave its highest significant value when bean plants were irrigated by surface drip irrigation system (SDI) at 40 % of available water. The effect of interaction on pod weight was not significant for the two varieties as well as pod length for contender variety Keywords: Phaseolus vulgaris, water application, surface drip irrigation, subsurface drip irrigation, yield and quality, crop coefficient, evapotranspiration, available water, salt accumulation and soil moisture.
2015
Ph.d
Minufyea
Agriculture