factors affecting yield curve in india
Yellow sarson (Brassica rapa var. trilocularis) is one of the important rabi oilseed crop under rainfed residual fertility situation in Assam, India. It is mostly used as condiments, spices and leafy vegetables as well as for extraction of oil. Proper planting geometry helps in altering canopy architecture affecting light interception and CO2 assimilation, which further affects the productivity. Among various agronomic factors responsible for crop yield, optimum plant population and fertilizer application are of paramount importance as fertilizer application contributes 18-73 per cent in yield increase of rapeseed-mustard crop.Nitrogen helps in better partitioning of photosynthates to reproductive parts which increases the seed-stover ratio and enhances the yield. Results of field experiments revealed that seed and stover yields of yellow sarson were recorded highest in bi-directional sowing method. All the growth and yield attributing characters, seed and stover yield and harvest index increased with the increase in levels upto 90 kg N/ha; however, the oil content, oil yield and nitrogen use efficiency was significant only upto 60 kg N/ha.