Climate change shocks and crop production: the foodgrain bowl of India as an example

Climate change shocks and crop production

Abstract

 Global warming is causing climate change (CC) characterized by increased frequency of heatwaves, droughts, erratic rains, hailstorms, cloudbursts, floods, landslides etc. The CC has already adversely affected ecosystems. In spite of efforts to mitigate greenhouse gas emissions, which lead to warming, the global temperature during 2011-2020 was 1.1C above that during pre-industrial era. The projections are that warming will continue to increase and adverse effects will intensify particularly in developing countries like India. In India a number of studies have recorded wide spatial variability in rainfall, though, many reported a general overall negative trend since mid-20th century. Further, varying pattern of rainfall has been recorded in three agroclimatic regions of Punjab state, the granary of India. Unseasonal rains followed by spiked temperature during rabi 2021-22 reduced wheat yield In Punjab by 651 kg/ha and by 301 kg/ha in Haryana compared to 2020-21. Further, the grain was of lower quality. During kharif 2022, Southern Rice Black-streaked Dwarf Virus, appeared for the first time in Punjab and Haryana. Some farmers ploughed the affected fields. Adverse weather during rabi 2022-23 also, reduced wheat yield (143-150 kg/ha) in these states. At the national level, erratic weather during rabi 2021-22 and kharif 2022 caused loss about 3 mt of grain of each of wheat and rice. The projected increased adverse effects due to intensified CC include food insecurity. Thus, there is an emergent need to accelerate implementation of adaptation and mitigation strategies in agriculture. Conservation agriculture conserves land and water resources, environment and biodiversity, reduces heat and drought stresses, captures carbon and improves soil health. The adaptation options include cultivar improvement, altering growing seasons, crop diversification, and sustainable soil and water resource management. In the process of adaptive management of crop production, adjusting sowing dates and breeding cultivars having varying duration in consonance with CC has been one of the central aspects. Shifting sowing dates to find appropriate crop cultivation season is a low-cost measure. However, cultivar development is time and resource consuming. Novel biotechnological tools enable fast cultivar development with precision, and facilitate mobilization of genes in wild-weedy relatives, which are rich in genes conferring resistance/tolerance to biotic and biotic stresses, required to combat CC challenge. In view of CC stress on water resources, improving water use efficiency has gained importance. Sensor-based micro-irrigation/fertigation has great potential to enhance water and fertilizer use efficiency. Similarly, the application of other smart technologies like nanotechnology, sensor-based pesticide application, bio-fertilizers and bio-pesticides, need to be mobilised. In view of agro-ecological diversity in India, right-sized region-specific technology packages have to be developed implying that crop research will expand exponentially. This needs strengthening of human resources and institutional infrastructure, expanding and linking basic and applied researches, and fortifying inter-disciplinary/inter-institutional collaborations to develop and diffuse technology innovations. Enabling factors include enhanced funding and international cooperation. All out efforts are needed to have more climate-resilient agriculture.