Direct and residual effect of nutrient management in maize (Zea mays) - wheat (Triticum aestivum) cropping system

Abstract

A field experiment was conducted at New Delhi to investigate the response of maize (Zea mays L.) - wheat [Triticum aestivum (L.) emend. Fiori & Paol.] cropping system to different nutrient-management practices during 2003-04 and 2004-05. The highest leaf-area index (LAI), yield attributes and yield of maize were recorded with the application of 120 kg N + 26.2 kg P + 41.5 kg Wha, closely followed by 120 kg N + 5 kg Zn + 10 t FYMIha. The LAI, yield attributes and yield of wheat were found maximum at the residual fertility of 5 kg Zn + 20 t FYMlha. Wheat gave 22.7% more yield at residual fertility of 5 kg Zn + 20 t FYMIha. The data on maize-wheat system indicated that when 120 kg N + 5 kg Znlha was applied with 10 t FYMIha, production efficiency (46.0 kglha-day), total pro- ductivity (10.8 tlha), net returns (Rs 46,784lha) and benefit : cost ratio (2.17) were the maximum. The Zn uptake by maize and wheat was the highest at 120 kg N + 5 kg Zn + 10 t FYMIha and 5 kg Zn + 20 t FYMIha, respectively. Except available P at 60 kg N + 10 t FYMIha, 5 kg Zn + 10 t FYMIha and 5 kg Zn + 20 t of FYMIha, all the nutrients increased in the soil at different fertility levels. Higher residual organic C and available N, P, K and Zn in the soil were obtained with 5 kg Zn + 20 t FYMIha. It was concluded that combined application of 120 kg N + 5 kg Zn +I 0 t wheat cropping system. FYMIha was essential for higher productivity and profitability of maize -