Long-term influence of nutrient management on productivity and profitability of maize (Zea mays)-wheat (Triticum aestivum) cropping system

摘要

A long-term fertilizer experiment on maize (Zea mays L.)-wheat (Triticum aestivum L.) cropping system was initiated during 1983 at the Birsa Agricultural University farm, Ranchi, Jharkhand. The present investigation was part of this long-term experiment started after 29 crop cycles during 2013-14 and 2014-15, to find out the effect of long-term fertilization on productivity and economics of maize-wheat cropping system. The experiment was laid out in partially confounded design with 18 treatments and1 control with 4 replications. Treatment comprised 3 levels of nitrogen (40, 80 and 120 kg N/ha), 3 levels of phosphorus (0, 40 and 80 kg PjOj/ha) and 2 levels of potassium (0 and 40 kg K20/ha). Results showed that balanced fertilization of maize-wheat cropping system with Ni2oPso^4o kg/ha resulted in the maximum grain yield of maize (4.21 t/ha), wheat (4.52 t/ha) as well as maize-equivalent yield (9.41 t/ha) with net returns of 67,396/ha and benefit: cost ratio (1.09). Continuous application of 120 kgN/ha alone for more than 30 years drastically reduced the grain yield of maize (0.94 t/ha), wheat (1.50 t/ha) and maize-equivalent yield (2.66 t/ha), which was 29.05% less than the control (1.32 t/ha, grain yield of maize). However, an application of 40kg P205/ha along with nitrogen remarkably improved the productivity of individual crop as well as cropping system.