Sustainability of rice production in the northwestern indo-gangetic plains

Rice is a vital crop for India, contributing around 30 percent of calories consumed in the country and providing a crucial source of income from exports. However, due to climate change and conversion of land for other uses, rice growing area in India is projected to decline by 6-7 million hectares (ha) by 2050, while production must increase by 1.1% annually over the next four decades to achieve rice self-sufficiency for the country.

As there is limited opportunity to horizontal expansion of cultivable land, the predicted increase in demand must be met through increasing rice yields in regions with low yields and maintaining existing yields in high-yielding areas. This must be achieved using sustainable farming practices: currently, 90 percent of total greenhouse gas (GHG) emissions of monsoon season cropped cereals in India is caused by rice cultivation, as is 80 percent of the energy and water used in agriculture.

Scientists found that in the Northwestern Indo-Gangetic Plains (IGP) of India, yield gaps were small (ca. 2.7 t ha^−1, or 20% of potential yield) mainly because of intensive production system with high input use. Using management data from 4,107 individual farmer fields, the study highlighted scope to reduce nitrogen (N) inputs without compromising yields in this intensive production system.

Findings show evidence of and methodology for the quantification of yield gaps and approaches that can improve resource-use efficiency, providing a possible alternative approach that could be reproduced elsewhere for other crops and contexts. It is recommended that future research focuses on ways to reduce other production inputs without compromising the yields in such intensive production systems.

This paper is the result of Harishankar Nayak’s PhD training in collaboration with the Indian Council of Agricultural Research (ICAR) jointly supervised by the researchers at the Indian Agricultural Research Institute (IARI) and International Maize and Wheat Improvement Center (CIMMYT).

Read the study: Rice yield gaps and nitrogen-use efficiency in the Northwestern Indo-Gangetic Plains of India: Evidence based insights from heterogeneous farmers’ practices

Cover photo: A farmer stands in his rice field at a Climate-Smart Village in the Vaishali district of Bihar, India, as part of the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS). (Photo: DK Singh/CIMMYT)