Effect of burned rice straw, phosphorus and nitrogen fertilization on wheat (Triticum aestivum L.)

This investigation was carried out in the Experimental Farm at Ghazala Village (Faculty of Agriculture, Zagazig University, Egypt) during two successive seasons (2014/2015 and 2015/2016) to study the effect of rice straw burning (rice straw plowing down and rice straw burning), phosphorus (P) level (0 and 15.5 kg P2O5/fad [fad = faddan = 4200 m2 and ha = 2.38 fad]), and nitrogen (N) level (30, 60 and 90 kg N/fad) on wheat (Triticum aestivum L. cv. Gemmiza 11). Burned rice straw significantly decreased the flag leaf area, spikes number/m2, 1000-grain weight, grain and total yields/fad. The increase of P level to 15.5 kg P2O5/fad produced significant increase in plant height, flag leaf area, grain weight per spike, 1000-grain weight but, decreased the number of spikes/m2 and the grain yield/fad and harvest index. The increase of N level up to 90 kg N/fad gave significant increase in grain yield and yield attributes except the number of sterile spikeletes/spike and 1000-grain weight which were decreased.