Impact of N and K-Fertilization on Yield of Wheat (Triticum aestivum-L.) Grown under Different Soil Salinity

Document Type : Original Article

Authors

1 Soil Dept. Fac. of Agric., Kafr EL-Sheikh Univ

2 Soils, Water and Environment Research Institute, A R C.

Abstract

Three field experiments were carried out during two successive seasons of 2005/06 and 2006/07 at Kafr El-Sheikh Governorate to study the effect of N, Kfertilization on wheat yield under three levels of soil salinity. Grain and straw yield of wheat (Triticum aestivum) cv.Sakha 94 had significantly increased with increasing of N application up to 140 kg fed.-1under different soil salinity. The yield was also increased with application of 50kgfed.-1K2O. Results indicated that there were highly significantly effects on grain and straw yield of wheat during the two growing seasons due to the interaction between N-K where the grain yield were recorded the highest mean values (23.95, 24.01, 20.86, 20.95 and 19.05, 19.60) by N application of 140Kg fed.-1 plus 50Kg fed.-1 K2O for normal soil, medium saline soil and high saline sodic soil in the two growing seasons, respectively. The straw yield were 4.798, 4.787 ton fed.-14.084, 4.143 ton fed.-1 and 3.363, 3.387 ton fed.-1 by nitrogen rate of 140Kg fed.-1 plus 50Kg K2O fed.-1 for normal soil, medium saline soil and high saline sodic soil in the two growing seasons, respectively. The N-uptake and recovery by wheat yield was increased with increasing application of nitrogen, but decreased as soil salinity increased, and increased by potassium application. The response of nitrogen application reached to 80kgN/Fed. in normal soil but by increasing N application up to 120kg N/Fed. in medium and high saline soils The highest relative variations of N recovery were +18.2%, +12.4% and +17.1% were recorded by application of N 40 in normal soil and N 120 in medium saline soil and high saline sodic soil, respectively. Nitrogen use efficiency (NUE) by wheat yield was decreased with increasing both application of nitrogen and soil salinity but improved by application of 50 kg fed.-1 K2O, with relative variations of 20.4% and 11.9 % with N80 for normal soil and medium saline soil, respectively. To achieve the highest yield of wheat (Triticum aestivum) cv.Sakha 94, it is recommended to apply nitrogen at the rate of 120kgN/Fed. And 50 kg fed.-1 K2plus 22 kg P2O5/fed. in non saline soil and application of N at the rate of 140kgN/Fed.and 50 kg fed.-1 K2O plus 22 kg P2O5/fed.in medium saline and highly saline sodic soil, respectively.

Main Subjects