The Impact Of Short Crop Rotation And Residues On Soil Fertility And Cotton Yield Under AridCondition

摘要

Soil fertility and crop productivity in arid regions are influenced by properly conducted crop rotation system and residue management approaches. The field experiment was conducted to reveal the impact short crop rotations system and crop residue in soil quality and crops yield during 2005-2010 at the Central Experimental Station of the Cotton Breeding, Seed ProductionandAgrotechnologies Scientific Research Institute, Tashkent, Uzbekistan.Due to tilling crop residues into soil organic matter (humus) and total nitrogen content increased in the soils up to 0.035-0.042% and 0.018-0.021% respectively. We revealed the crop residue amount of winter wheat and soybean grown as a main crop was from 4.0 to 5.0 t ha"1. The plant residue of intercropped winter crops such as the peas, oats and rye was 9.5-14.5 t ha"1 during autumn-winter season. It was observed that nitrogen, phosphate and potassium of the plant residue serve as a source of nutrientsafter its decomposition in the soil.The results showed that the cotton yield were much higher in the short crop rotation system 2:1 (1 year winter wheat + soybean as a summer crop : 1 year winter wheat + soybean as a summer crop followed by intercropping of oat, green peas and winter rye):l year cotton, and consisted 35,8; 26,2 sentner ha"1 compare control respectively. Crop residues retention and planting legumes such assoybean significantly enhanced the cotton yield.