Effect of Planting and Ex-situ Mulching on Growth, Productivity, Profitability and Nutrient Uptake in Maize-Wheat Cropping Sequence

Abstract

In Indo-Gangetic Plains (IGP) sustainability of rice–wheat system is at high risk due to increasing scarcity of resources (labour, water, and energy) and cost of production, substituting rice with maize is of utmost important to arrest degrading natural resources (soil and air quality, and ground water) and to halt the decreasing factor productivity of cereals crops in the region. A field experiment was conducted to evaluate the effect of planting (flat vs raised bed) and ex-situ mulching on crop growth, yield, economics and nutrient uptake in maize (Zea mays) - wheat (Triticum aestivum) system. On 2-years mean basis, higher plant height and number of cobs per plant of maize were recorded with Sesbania (226.84 cm) and Brassica (1.42) mulching, respectively. Raised bed planting of wheat improved the number of spikes m-1 row length by 4.3 and 10.86% and grains per spike by 10.46 and 9.4% over flats in the year 2009-10 and 2010-11, respectively. Jatropha mulching improved the plant height, leaf area index (LAI) and spike/m row length of wheat over no mulching. Highest 1000-grain weight (40.21 g) was recorded with Jatropha mulching in wheat over the years. Higher system productivity (3.49%) and profitability (9.96%) was recorded on flats compared to raised beds. Mulching with Sesbania, Jatropha and Brassica increased systems productivity and profitability by 10 and 12%, respectively. NPK uptake was improved by 7.70, 7.10 and 12.97% under flats over raised beds in wheat on 2-years mean basis. The systems N, P and K uptake was higher by 13.49, 12.94 and 12.71 with Jatropha and by 12.38, 13.18 and 11.14% with Sesbania, respectively over no mulching. On system basis, nitrogen gained was 40.06% higher in raised beds compared to flats (36.2 kg ha-1). Soil nitrogen pool/ the nitrogen surplus potential was recorded 16.33% higher with flats over raised beds (147.1 kg ha-1). On average, raised beds with ex-situ mulching improved soil biological properties in maize-wheat system. Cultivation of maize-wheat system on flats with ex-situ mulching of Sesbania was found profitable under irrigated ecosystem.