Evaluation of nutrient sources for organic production of rice (Oryza sativa)-wheat (Triticum aestivum) cropping system in north-west India

A field experiment was conducted during the rainy (kharif) season 2009 to winter (rabi) season 2011–12 at Ludhiana to evaluate different sources of nutrition for organic production of rice (Oryza sativa L.)-wheat (Triticum aestivum L.). The experiment was laid out in a split-plot design with main plots consisting of recommended chemical fertilizers (RDF), farmyard manure (FYM200) to supply 200 kg N/ha, FYM100 to supply 100 kg N/ha and unfertilized control. The subplots included jeevamrit as soil application, jeevamrit as soil and foliar application and control plot without jeevamrit. Rice grain yields with FYM200 and FYM100 were lower by 13.3 and 17.7%, respectively, than RDF during the Ist year and were statistically at par during subsequent years. The reduction in wheat grain yield during 1st year was 34.6 and 40.5% with FYM200 and FYM100, respectively, as compared to RDF. The corresponding reductions during 2nd and 3rd year were 18.6, 36.2 and 11.7, 29.5% respectively. The FYM200 proved significantly better than FYM100 in wheat. Soil organic carbon improved with FYM at both the rates as compared to RDF. The soil microbial population increased with application of jeevamrit, but it did not influence the productivity of the crops. Thus, rice yields at par with RDF could be obtained with both the FYM levels of FYM100 and FYM200 from 2nd year onwards; however, wheat yields even with FYM200 remained lower than RDF in 3rd year also. Jeevamrit was not effective in influencing the grain yield of rice and wheat, indicating its inability to contribute to the nutrition of these crops.