RATIONALIZATION OF IRRIGATION WATER USE FOR FABA BEAN (vicia faba L.).

Abstract

The present investigation was conducted at Fayoum Agric. Res. Station (Tamiea), Fayoum Governorate, Egypt during 2009/2010 and 2010/2011 seasons to study the combined effect of ridge width (60, 80 and 100 cm) and available soil moisture depletion (35, 55 and 75% ASMD) on seeds yield, yield components and some water relations of faba bean crop (Giza -843 hybrid). A split plot design with four replications was used in both seasons. The main obtained results were as follows:Plant height (110.6, 102.7cm), pod number/plant (20.9, 19.10), seed weight/plant (50.2, 48.9 gm), 100-seed weight (64.5, 62.3 gm) and highest seed yield/fed (1611.51 and 1402.2 kg/fed in 2009/2010 and 2010/2011 seasons, respectively), resulted from planting on ridges of 60 cm width and irrigation at 35% ASMD, surpassed significantly those obtained from the other treatments, in the two successive seasons. However, the highest number of branches/ plant were detected from planting on ridges of 80 cm width and irrigating at 35% ASMD, in the two seasons.Seasonal consumptive use (ET C ) averaged 33.15 and 33.00 cm in 2009/2010 and 2010/2011, respectively. Planting on ridges of 60 cm width and irrigation at 35% ASMD gave the highest ET C values, i.e., 37.95 and 36.66 cm in the two successive seasons. The lowest ET C values, i.e., 28.62 and 30.14 cm were detected from planting on the widest beds and 75% ASMD treatment in both seasons, respectively.Daily ET C rates were low during Oct., Nov. and Dec. then increased during Jan. reached its maximum values during Feb. and declined again till harvesting. The crop coefficient (K C ) values were 0.49, 0.62, 0.73, 0.81, 0.90 and 0.59 for Oct., Nov., Dec., Jan., Feb. and March, respectively. (average of the two seasons)The highest water use efficiency values i.e., 1.011 and 0.911 kg seeds/m 3 water consumed were obtained from planting on ridges of 60 cm width and irrigation at 35% ASMD treatment in 2009/2010 and 2010/2011 seasons, respectively.Results indicate that planting on wide ridges of 100 cm width safe about 11.45% of the water consumed and produced an acceptable economic seed yield Key words: faba bean, yield, yield components, ridge width, irrigation regimes, water relations. INTRODUCTIONFaba bean considered the most important winter legume crop in Egypt. The high protein content of its seeds (28%) gave this crop the greet importance in human consumption, as well a sheep source of protein. Also, the role of this crop in improving soil characteristics after harvesting, because it increased soil fertility as nitrogen fixation in soils by root nodules, leaving about 20-25 units of N/fed, which will be beneficial for the next cultivated crop.Concerning, the effect of ridge width many investigators have been reported a tendency for increase in yield and some yield components such as no. of branches/plant, no. of pods, seeds weight/plant and 100-seed weight by