Performance of Target Yield based Fertiliser Prescription Equations inice-Wneat Cropping System m Punjab

摘要

Fertiliser use efficiency is very important factor that needs to be considered in crop production as inefficient use of fertilisers leads to not only economic loss but also may cause environmental hazards. The site-specific nutrient management is key strategy to improve nutrient use efficiency. Field verification trials were conducted with rice and wheat at farmers' fields to ascertain the validity of soil test based fertiliser prescriptions for achieving specific yield targets in alluvial soils of Punjab. Different fertiliser recommendation methods along with fertiliser doses calculated through fertiliser adjustment equations for varying levels of targeted yields of rice and wheat were evaluated. The fertiliser recommendations based on targeted yield concept were found more precise and give higher net returns as compared to soil test recommended dose. The target yields were obtained between 5 to 10% variation of the targeted yield of wheat and rice. Yield target of 7.0 t ha~(-1) in rice and of 5.5 t ha~(-1) in wheat provided the highest yield and net benefit over farmers' practice. The per hectare increase in income over farmers' practice varied from Rs. 1780 to 3398 in case of rice and Rs. 1632 to 5951 in case of wheat. The benefit cost ratio in both rice and wheat was higher in case of target yield approach followed by soil test recommended dose. Thus the practice of fertiliser recommendations based on soil test for desired yield target of rice and wheat proved superior to soil test recommended dose and farmers' practice.