Crop and Residue Management Improves Productivity and Profitability of Rice–Maize System in Salt-Affected Rainfed Lowlands of East India

Abstract

This study was conducted over 3 years in a salt-affected coastal rainfed lowland ecosystem. Farmers most commonly grow tall rice varieties in the wet season to cope with flash and/or stagnant floods, leading to large amounts of rice residue production. Most of the land remains fallow during the dry season because of increased salinity and scarcity of freshwater for irrigation. The study aims to provide options for increasing cropping intensity through management of crop residues (CR) and soil salinity, conservation of soil moisture, and reduction in production cost. The rice–maize rotation was assessed with rice as the main plot as (1) puddled transplanted rice (PTR) with CR of both rice and maize removed, (2) PTR and 40% CR of both crops retained, (3) dry direct-seeded rice (DSR) with CR of both crops removed, and (4) DSR with 40% CR of both crops retained. Maize in the dry season was supplied with different N levels as sub-plots—control (0 kg N ha−1), 80, 120, and 160 kg N ha−1. DSR, when combined with CR retention (DSR + R), reduced soil salinity. The increase in rice grain yield with CR retention (observed in second and third years) and crop establishment (higher in DSR versus PTR in the third year) was 16 and 24%, respectively. The cost of production increased by 17% (USD 605 ha−1) in PTR compared with DSR (USD 518 ha−1). CR retention reduced irrigation water requirement by 37% and N requirement by 40 kg ha−1 for hybrid maize. When CR was removed (−R), the N requirement for hybrid maize increased to 160 kg N ha−1 compared to when it was partially (40%) retained, where the requirement was 120 kg ha−1 with similar yields. Available N was highest under DSR + R (314 kg ha−1) and lowest under PTR − R (169 kg ha−1), and it also increased with increasing N application up to 120 kg ha−1 (+R) and 160 kg ha−1 (−R). The results of the study hold promise for increasing cropping intensity and farmers’ incomes, with broader implications for increasing productivity on about 2.95 million hectares currently under a rice–fallow system in eastern India, and in coastal areas affected by similar conditions in South and Southeast Asia.

Evaluation of maize (Zea mays) genotypes under different nitrogen levels in a Trans-Gangetic Plains region

“…Decreased maize yield with excess nitrogen fertilizer application may be associated with reduced root growth and harvest index, and higher pest infestation. Conservation agricultural practices such as crop residue retention could reduce N requirement of hybrid maize by 40 kg/ha without affecting the kernel yield (Sarangi et al, 2020).…”

Drip irrigation in maize (Zea mays)-based cropping systems

“…Maize is the third most important food crop, after rice and wheat (USDA 2011), and considered a commercial crop with various industrial uses apart from its use as human food and also serves as feedstock for animals (Sarangi et al, 2020). Given the increasing demand for maize as both fresh and processed food, the challenge is to obtain higher yields from less water to maximize the crop's water productivity (WP).…”

Effect of 2, 4-D sodium salt on weeds, growth and yields in rabi maize (Zea mays L.)

“…After rice and wheat, maize is India's third most significant cereal crop. Recently in India, there is an increasing interest to promote non-rice crops such as maize that requires less water during the dry season to enhance food production and generate more income for farm-ers (Sarangi et al, 2020). It can be produced in a variety of climates, ranging from extreme semi-arid to sub-humid and humid, which predominantly occupies 82% area under cultivation in rainy (kharif) season and nearly 10% in winter (rabi) season (Sairam et al, 2023a).…”