El-Atawy Gh. Sh.; R. H. Atia and A. S. M. El-Saady( 2010). Potential Productivity of Tomato as Affected by Irrigation Water Amounts and Nitrogen Fertilization, Under Drip Irrigation, at Northwest Delta, EgyptJ. Soil Sci. and Agric. Eng., Mansoura Univ., Vol.1 (10):1037-1047, 2010
Abstract: Two field experiments were carried out during 2008 and 2009 growing seasons at Wady Elnatroon, El-Behera governorate to investigate the effect of irrigation amounts and nitrogen rates on tomato yield, under drip irrigation method in Northwest Delta. The soil of the experimental fields was sandy loam. The electrical conductivity of irrigation water was 1.1 dSm-1. The treatments were arranged in a split plot design with four replicates. Four amounts of irrigation water were daily applied on a bases of 100%, 90%, 80% and 70% of ETc with four nitrogen rates i.e. zero (control), 150, 225 and 300 kg N fed.-1, (1 feddan = 0.42 hectar). Seasonal plant water consumption or evapotranspiration of irrigation treatments varied from 42.88 cm to 57.93 cm in both seasons. Irrigation treatments had significant effects on yield and water use
efficiency. The tomato yield varied from 20.188 to 44.367 ton fed.-1. The highest total yield (44.367 ton fed.-1) was obtained from irrigation at 100% of water requirements and fertilized with 300 kg N fed.-1 in both seasons. The highest mean values of NUE (101.19 kg fruits kg-1 applied N fed.-1) was obtained from 100% of ETc and 150 kg N fed.-1, while, the lowest value (60.39 kg fruits kg-1 applied N fed.-1) was obtained from 70% of ETc and 300 kg N fed.-1. The highest values of N, P and K concentrations in tomato plants and its fruits, were obtained from irrigation at 100% of ETc compared to 90, 80 and 70% of ETc. The highest values of water use efficiency and irrigation water use efficiency(21.15 kg fruits m-3 of water consumed and 18.60 kg fruits m-3 of water applied, respectively) obtained from tomato plants irrigated with 70 % of water requirement and fertilized with 300 Kg N fed.-1. It could be concluded that for obtaining a good tomato yield and facing the irrigation water shortage, daily irrigation with 100% of ETc must be added with 300 kg N fed-1 under the sand loam soil texture in Wady Elnatron region and similar conditions.
Keywords: (Tomato, drip irrigation, N fertilization, water consumptive use, water use efficiency.)
