YIELD PERFORMANCE, ECONOMICS AND SOIL FERTILITY THROUGH DIRECT AND RESIDUAL EFFECTS OF ORGANIC AND INORGANIC SOURCES OF NITROGEN AS SUBSTITUTE TO CHEMICAL FERTILIZER IN RICE-WHEAT CROPPING SYSTEM PUBLISHEDSanjay KOUSHAL, A. K. SHARMA, Amarjit Singh SODHI
A field experiment was conducted during kharif and rabi seasons of 2006-07 and 2007-08 respectively at Jammu, (J&K) to study the direct and residual effects of organic and inorganic sources of nitrogen in rice-wheat cropping system on yield performance, economics and soil fertility in sandy clay loam soil. Application of 100 % recommended dose of nitrogen from urea significantly influenced the yield and economics of rice in 1 st year of experiment. Whereas during the 2 nd year of experiment application of 50 % recommended dose of nitrogen from vermicompost and rest through chemical fertilizer (urea) produced significantly highest grain and straw yield of rice. However, gross return, net return and B: C ratio values were significantly highest in the plot which received 25 % N through vermicompost and rest through chemical fertilizer. During wheat season the plots received 100 % recommended dose of fertilizer produced significantly highest yield, gross return net return and B: C ratio which is significantly at par with 75 % of the recommended dose of fertilizer applied to wheat. So, substitution of chemical fertilizers through organic sources likes vermicompost and FYM by 50 % of recommended dose of nitrogen would be better proposition towards reduction in the use of chemical fertilizers in rice and 25 % in wheat. As for as soil fertility is concerned organic sources of nutrients applied to previous crop have edge over chemical fertilization in fertility build up, particularly organic carbon, total and available NPK. The application of 100 per cent nitrogen through vermicompost significantly increased the available N, P, K status of surface soil which was closely followed by that obtained with 100 per cent nitrogen through FYM. There was a buildup of organic carbon and reduction in bulk density in soil where 100 per cent organic sources of nutrients followed by 50 per cent were applied.
rice, wheat, Vermicompost, FYM, inorganic fertilizer, econmics, yield