Response of brown sarson (Brassica campestris subsp oleifera var. brown sarson) to residual effect of organic manure, nitrogen and transplanting dates of rice (Oryza sativa)

A field experiment was conducted at Shalimar campus of Sher-e-Kashmir University of Agricultural Sciences and Technology, during the rainy and winter seasons of 1995-96 and 1996-97 on silty clay-loam soil. The treatments comprised 2 dates of transplanting (15 and 30 June) and 3 levels of organic manure (control, rice straw litter and FYM @ 10 tonnes/ha) assigned to main plots and 4 levels of N (0, 50,100 and 150 kg/ha) in subplots, tested in split-plot design with 3 replications. In the subsequent winter season brown sarsoh [Brassica campestris L. ssp. oleifera (Metzger) Sinsk. var brown sarson] was sown on 15 October during both the years in each plot. Seed yield, yield attributes, siliquae/plant, 1,000-grain weight and nutrient uptake of brown sahson increased significantly as result of residual effect of application of organic manure and nitrogen on preceding rice (Oryza sativa L.) crop. However, 15 June transplanting of rice with higher levels of nitrogen (100 and 150 kg/ha) with organic manure (rice straw litter and FYM) application, followed by brown sarson over 2 years recorded positive net gain of soil nitrogen.