Opportune science and promotion boost climate-smart farming in India
With the pandemic lockdown driving millions of migrant workers and day laborers away from northern India to their home villages, prospects for the region’s rice-wheat cropping rotation, which feeds the nation and relies heavily on field workers, looked grim. But scientists of the International Maize and Wheat Improvement Center (CIMMYT) and India seized a glimmer of promise for farmers and policymakers, amid the dark crisis.
“Any delay in the labor-intensive transplanting of rice seedlings pushes back rice harvests; this then causes wheat to be sown later and sorely affects wheat yields,” explained M.L. Jat, a systems agronomist who leads CIMMYT’s climate-smart agriculture research portfolio in South Asia. “Also, farmers normally gather and burn millions of tons of rice straw before sowing wheat, generating regionwide pollution. That’s always harmful but would be worse if burning were delayed until the cold weather of late fall or winter.”
For long, CIMMYT and national partners have studied and advocated for resource-conserving farming practices to help address perennial rice-wheat rotation problems, including severe water and soil depletion and falling profitability. Among alternatives are sowing rice in non-flooded fields, adding or substituting crops in the rotation, and planting wheat directly into just-harvested rice fields without burning the straw or plowing.
The latter is called “zero tillage” and has been adopted already on a limited area in northern India. The practice helps lessen severe seasonal air pollution, profits farmers by $150-200 in reduced costs and improved yields per hectare, saves an average 15% in irrigation water, and allows early wheat planting so that the crop can be harvested before the pre-monsoon heat scalds the grain, according to Harminder S. Sidhu, principal research engineer at the Borlaug Institute for South Asia (BISA), a research center for which CIMMYT shares oversight with the Indian Council of Agricultural Research (ICAR).
“Zero tillage for wheat requires use of a special tractor-mounted implement that opens grooves in the soil, drops in wheat seed and fertilizer, and covers the seeded row with shredded rice residues, all in one pass,” Sidhu explained. He and colleagues in India and CIMMYT developed and refined the implement, known as the Happy Seeder, over 15 years. Conventional wheat seeding practices involve first gathering and burning rice straw, followed by numerous and costly tractor passes to plow, harrow, and plank the field, reforming it from a paddy, and then to sow the wheat.
Unprecedented challenges require visionary measures
After a 2020 study by researchers at CIMMYT, ICAR and the International Rice Research Institute (IRRI) described the potentially disastrous outcomes of rice-transplanting delays, Jat and the other authors shared with policymakers their findings and recommendations, including the alternatives described above. Notably, after receiving a one-page summary, the Chief Minister of Punjab, the leading rice-wheat farming state, released a video address supporting the scientists’ conclusions.
Jat and colleagues then moved quickly to promote adoption of the alternative practices, helping to facilitate subsidies for purchases of the Happy Seeder and ensuring the timely availability of machines and other inputs.
As a result, in 2020 farmers substituted dry-seeded rice for flooded and manually-transplanted rice on 500,000 hectares, which represents 34% more area converted to the new practice than the cumulative total for the previous 10 years. Additionally, 330,000 hectares were sown to alternative crops, principally cotton, maize and legumes.
“The central and state governments in northwestern India, as well as extension agencies, are promoting no-burn alternatives that include direct seeding of wheat using the Happy Seeder, and there are state directives and fines to stop straw burning, especially in this unprecedented time of the COVID-19 pandemic,” Sidhu said.
Partners and funders
Borlaug Institute for South Asia (BISA), governments of India and of the states of Haryana and Punjab, Indian Council of Agricultural Research (ICAR), an Punjab Agricultural University (PAU), This work benefits from the partnerships and support of the Bill & Melinda Gates Foundation, Georgia Institute of Technology (Georgia Tech), iDE, the International Food Policy Research Institute (IFPRI), and the International Rice Research Institute (IRRI).