Sustainable Intensification of a Rice–Maize System through Conservation Agriculture to Enhance System Productivity in Southern India

Abstract

Integrated management of rice–maize systems is an emerging challenge in southern India due to improper rice residues and tillage management in maize crops. Conservation agriculture (CA) practices such as a reduced tillage and maintaining stubble mulch may hold the potential to increase yields, reduce crop establishment costs and increase farm incomes. A five-year trial was performed to study the effect of different CA and establishment methods in rice on system productivity, profitability, and soil carbon status in a rice–maize system. In the rainy season, the trial consisted of two main treatments: (i) normal manual transplanting and (ii) direct-wet seeding, and three sub-main treatments at different sowing dates with fifteen day intervals. In addition, in the winter season, two tillage treatments (conventional and minimum tillage) were imposed over the rainy season treatments. Both rice and maize were grown under irrigated conditions. The results showed that sowing times at 15 day intervals did not impact the yield significantly. Transplanted rice obtained a significantly higher grain yield during the first four years, but in the last year, the yield was similar in both of the establishment methods. In the winter season, conventional tilled maize recorded a higher cob yield than under the minimum tilled treatment, except for the last year, where both the tillage treatment effects were the same. System productivity of CA-based minimum tilled rice–maize was inferior during the first three years but was superior to the conventionally tilled method in the fourth and fifth year. Pooled analysis revealed that the conventionally tilled rice–maize system resulted in a similar system productivity as that of the CA during the study period. The cost–benefit analysis revealed that transplanted rice and conventionally tilled maize fetched higher net returns of INR 111,074 and INR 101,658/ha, respectively, over the direct-wet seeded rice and CA. In addition, the 15 July rice sown followed by the maize system led to an increase in irrigation water productivity by 15.7 %, and the total water (irrigation + rainfall) productivity by 27.1 % in the maize crop compared with the 30 July sown system. The CA-based rice–maize system resulted in a significantly higher very labile (0.194 %) and labile (0.196 %) carbon concentration at a 0–5 cm depth of soil compared to those under the conventional system. Thus, CA can be recommended for southern India and similar agro-ecological tropic and sub-tropic conditions. This system can be followed with appropriate location-specific modification in South-Asian countries, where crop yields and soil health are declining as a result of continuous cereal–cereal crop rotation.

Comparison of System of Rice Intensification Applications and Alternatives in India: Agronomic, Economic, Environmental, Energy, and Other Effects

“…Similarly, the expenditures incurred for the operations involved in cultivation, such as tillage/land preparation, nursery-raising, transplanting, harvesting and threshing, were added up, and the costs of hiring tractor-driven machinery and the wages of human laborers (based on eight hours of work per day) were included in the cost of cultivation. The Government of India's minimum support price (MSP) for rice was used to calculate the value of production [32] and then to calculate the gross return. The net return was determined according to the equation: Net return = Gross return − Cost of cultivation A summary analysis was carried out for the economic returns from each crop establishment method as this is what farmers and policy-makers are most concerned about.…”

Nanotechnology Approaches for the Remediation of Agricultural Polluted Soils

“…Soil is an intricate and vital ecosystem that provides a wide range of essential ecosystem services, including provisioning (e.g., freshwater, timber, food, and fiber), regulation (e.g., climate control, erosion prevention, and flood mitigation), cultural (e.g., aesthetic and spiritual values), and supporting (e.g., physical support for plants, animals, and human infrastructure) services . Soil health is defined as “the ability of soil to function as a dynamic living system within the limits of an ecosystem and land-use practices, supporting plant and animal productivity, enhancing water and air quality, and promoting overall plant and animal well-being” . Soil is a constantly evolving natural resource that consists of diverse elements, including gases, minerals, salts, organic and inorganic matter, and living organisms.…”

“…Soil is a constantly evolving natural resource that consists of diverse elements, including gases, minerals, salts, organic and inorganic matter, and living organisms. It possesses biological, chemical, and physical characteristics that are sensitive to alterations, which can result from natural processes (such as volcanic eruptions, ore weathering, and forest fires) or, more frequently, from various human activities (disposal of household and industrial refuse and application of chemical fertilizers and pesticides to improve crop yields) …”

“…It possesses biological, chemical, and physical characteristics that are sensitive to alterations, which can result from natural processes (such as volcanic eruptions, ore weathering, and forest fires) or, more frequently, from various human activities (disposal of household and industrial refuse and application of chemical fertilizers and pesticides to improve crop yields). 9 Chemicals produced by humans and changes in the environment that occur naturally in the soil are the main causes of soil pollution. Soil contamination typically results from the breakdown of subterranean storage linkages, the use of pesticides, the seepage of polluted surface water into subsurface strata, the disposal of oil and fuel, the leaching of wastes from landfills, or the direct release of industrial wastes into the soil.…”

“… 8 Soil health is defined as “the ability of soil to function as a dynamic living system within the limits of an ecosystem and land-use practices, supporting plant and animal productivity, enhancing water and air quality, and promoting overall plant and animal well-being”. 9 Soil is a constantly evolving natural resource that consists of diverse elements, including gases, minerals, salts, organic and inorganic matter, and living organisms. It possesses biological, chemical, and physical characteristics that are sensitive to alterations, which can result from natural processes (such as volcanic eruptions, ore weathering, and forest fires) or, more frequently, from various human activities (disposal of household and industrial refuse and application of chemical fertilizers and pesticides to improve crop yields).…”