Global Maize Project in India: Ranchi, Jharkhand - Site Specific Nutrient Management in Maize-Wheat cropping system in Ranchi, Jharkhand

Productivity of maize and wheat grown in red and lateritic soils continues to be low due to poor nutrient use. Yield levels of maize can be increased 2 to 3 fold with optimal site-specific and balanced use of plant nutrients, which depends on the yield potential of the crop/varieties used and the inherent fertility of soil.

Three sets of field experiments were undertaken with wheat (variety K 9107) during rabi (November 2009 to March 2010) and maize (variety Pioneer-V92) grown during kharif (June to October 2010) at the University farm at Kanke, Ranchi. Experiment 1 was a long-term system evaluation of ecological intensification management and farmer fertilization. Experiment 2 studied the effect of rate and timing of N application. Experiment 3 estimated indigenous nutrient supply through omission plots in maize and wheat. The experimental soil was an Alfisol with sandy-loam texture, acidic soil pH (5.1 to 5.4), low organic matter (3.3 to 4.3 g/kg), medium available N (240 to 270 kg/ha) and P (31 to 45 kg/ha), and low K (133 to 161 kg/ha).

Maximum yield of wheat (4.8 t/ha) was obtained with application of N, P₂O₅ and K₂O at 150-80-90 kg/ha, where N was applied in three splits at 0, 25, and 45 days after sowing. Nitrogen, P, and K response, measured from omission plot yields, were 3.6, 1.1, and 0.5 t/ha, respectively. The farmer practice yield was 2.8 t/ha. Application of 240 kg N/ha in two equal splits (basal and V10) along with 100 kg/ha of P₂O₅ and K₂O produced the highest maize yield of 7.1 t/ha. Omission of N from the fertilization schedule caused a yield loss of about 5 t/ha. Yield loss due to P and K were around 2 t/ha. The maximum farmer plot yield was 3.2 t/ha. The experiment highlighted that system (maize + wheat) yield in Jharkhand could be increased from 6 t/ha (farmer practice) to about 12 t/ha through fertilizer best management practices.

These experiments are being continued to further optimize the N, P, and K rates and timing based on nutrient balance information and the generic relation between grain yield and nutrient content in biomass. IPNI-22