Yield, economics and nutrient uptake of wheat as influenced by organic manures and their residual effect on rice in rice-wheat system.

摘要

A field experiment was conducted during winter and rainy seasons of 2004-05 and 2005-06 at CCSHAU Rice Research Station, Kaul (Kaithal). The experiment consisted of combinations of six sources of organic manures viz., no organic manure, FYM @ 15 t/ha, vermicompost N₁₀₀, vermicompost N₁₅₀, vermicompost N₂₀₀ and vermicompost N₂₅₀ and five fertilizer levels viz., no chemical fertilizer, 25, 50, 75% recommended dose of nitrogen and 100% recommended dose of fertilizer (N₁₅₀, P₂O_{5 60}, ZnSO_{4 25} kg/ha). The studies revealed that grain yield increased significantly with each increasing dose of vermicompost upto N₂₀₀ and N₂₅₀. Vermicompost N₂₅₀, N₂₀₀ and N₁₅₀ were significantly superior to FYM and vermicompost N₁₀₀. Nitrogen, phosphorus and potassium uptake increased with the increasing rates of vermicompost. Grain yield was also increased significantly with successive increase in nitrogen and fertilizer levels during both the years. NPK uptake was found to be increased significantly with each increase in nitrogen and fertilizer level. Increasing rates of vermicompost and fertilizers resulted in more availability of NPK in soil except K availability in soil which decreased significantly with increase in nitrogen and fertilizer doses. Higher doses of vermicompost resulted in more availability of nutrients in soil after the harvest of wheat crop than FYM. Application of organic manure and fertilizers left residual effect on succeeding rice crop and it was observed that grain, straw and biological yields of rice were higher at higher levels of vermicompost as compared to its lower levels and FYM. Yields of rice increased significantly with each successive increase in nitrogen and fertiliser levels applied to wheat crop.