Effect of Nitrogen and Preceding Cropping Pattern on Yield and Yield Components of Rainfed Wheat

Abstract

Field experiment on carry over effect of preceding cropping pattern (millet, sorghum, mungbean and groundnut as sole and each in combination with groundnut repeated for two consecutive years 2007-2009) and current application of three doses of nitrogen (00, 45 and 90 kg ha^-1) on rainfed wheat was conducted at New Developmental Farm, Khyber Pakhtunkhwa Agricultural University Peshawar in rabi 2010. The experiment was laid out in randomized complete block design with split plot arrangement having three replications. Cropping pattern assigned to main plot while nitrogen levels to sub plot (5m x 1.8m). Soil analysis was carried out before sowing and after harvesting of crop. It showed that plots grown with mungbean (sole) had higher N content at both occasions (before sowing 0.41 g kg^-1 and after harvest 0.38 g kg^-1) as compared with other cropping patterns. All parameters were significantly affected by cropping pattern and nitrogen application except number of unproductive tillers m^-2 were not significantly affected by preceding cropping pattern. Groundnut and mungbean intercropping had significantly delayed anthesis and maturity. Mungbean (sole) or intercropped with groundnut as preceding crop had significantly produced taller plants, more: tillers m^-2, productive tillers m^-2, grains spike^-1, thousand grain weight, biological yield, grain yield and harvest index. Nitrogen application had significantly increase productive tillers m^-2 (225), grains spike^-1 (48), thousand grain weight (34g), grain yield (1448kg ha^‑1), biological yield (6126kg ha^-1) and harvest index (23%) as compared to control. Combination of mungbean as sole and 90 kg N ha^-1 produced significantly higher tillers m^-2 (263), more productive tillers (234) and higher thousand grain weight (32g). Cropping system of mungbean as sole or intercropping with groundnut as preceding crop and nitrogen application at rate of 90 kg ha^-1 seems to be the promising agronomic practices for growing wheat in rainfed areas.