Evaluation of Four New Bread Wheat (Triticum aestivum L.) Cultivars in Sandy Soils under Different Irrigation Regimes and Nitrogen Fertilizer Rates for Yield and Its Components

The present study was carried out (sandy soil under sprinkler irrigation) at El-Bustan area, ARC, in Egypt during the two seasons, 2009/2010 and 2010/2011. Four new bread wheat cultivars (Sids12, Sids13, Gemmeiza11 and Shandaweel 1) were evaluated under three irrigation regimes under sprinkler irrigation system (I1=2380 m 3 /ha, I2=3094 m 3 /ha and I3=3808 m 3 /ha) and two nitrogen levels (N1=119 and N2=238 kg/ha for grain yield and its components. This study was performed as split-split plot in using three replications. The results showed that the studied characters were significantly affected by irrigation treatments in both growing seasons. All characters showed highly significantly differences among applied N rates except for 1000-kernel weight in the second season and number of kernels per spike in the first season. Cultivars were significantly in number of spikes/m² and number of kernels/spike in the first growing season, while highly significantly differences in 1000- kernel weight, grain yield and biological yield in the second season. Sids 13 recorded the highest number of spikes/m², number of kernels per spike and grain yield in the first season. Meanwhile, Gemmeiza 11 recorded the highest 1000-kernel weight, grain yield and biological yield in the second season. The interactions of irrigation regimes × N nitrogen levels were highly significant for number of spikes/m² in the first season and for biological yield in both growing seasons. The interactions of irrigation treatment by cultivars were highly significant for number of spikes/m² in the first season, for number of kernels per spike in the both seasons and grain yield in the second season. The highest number of spikes/m² was obtained from Sids 13 under I3 irrigation treatments but the lowest number of spikes/m² was obtained by Gemmeiza 11 under I1 irrigation treatment in the first season. The highest value of number of kernels/spike was obtained from Sids 13 under I3 irrigation in the first season. While, Gemmeiza 11 gave the highest number of kernels/spike and grain yield under I3 irrigation treatment meanwhile, Sids 12 gave the lowest number of kernels/spike and grain yield under I1 irrigation treatment in the second season. The interaction between nitrogen rate and wheat cultivar was highly significant for 1000-kernels weight in the first season. The results show that Gemmeiza 11 gave the highest 1000-kernel weight under the highest nitrogen level while Sids 12 recorded the lowest 1000-kernel weight under the lowest nitrogen level. The interaction between irrigation treatments, nitrogen rate and wheat cultivar was significant for 1000-kernels weight, number of kernels/spike and biological yield in the first season. Cultivars were significantly in water use efficiency in the both growing season. Sids 13 had the highest water use efficiency among the four cultivars in the first season, while Gemmiza 11 had the highest value in the second season. Sids 13 and Gemmeiza 11 had average of 2.4 kg/m³/ha in both growing season. This finding implied that Gemmeiza 11 and Sids 13 could be recommended growing in sandy soils and both can use irrigation water efficiently.