Food security: Climate change is affecting the seeds that India depends on

In 2019, a group of 20 farmers in Andhra Pradesh’s ASR district ventured into seed production of finger millet (ragi) and little millet (samai) and hoped for a good return on their investment.

But for the next two years, unusual weather events ensured that the crops did not have grains good enough to be used as seeds. The seed production completely failed.

While farmers were eyeing to sell the seeds at Rs 35 per kg, in the end they had to sell the produce as a crop for Rs 25 per kg. This is not an isolated incident.

An increase in the number of days with extreme temperatures or rain has caused a decline in the quality and size of seeds across India. The availability of quality seeds is the basis for ensuring food security in the country but climate change has been posing a threat to this very foundation.

Grains of wheat and rice, the two major staples of India, have seen a shrinkage in recent years. According to Mississippi State University of the US, most wheat varieties require a temperature of under 30 degrees celsius during the day between February and March.

This is the time when the plant is germinating. Data with IMD shows that this 30 degrees Celsius limit often gets breached. In March 2022, there were several days when temperatures crossed 30 degrees Celsius. This ended up reducing the wheat yields in the north and central Indian states.

Research also shows that a 1 degree celsius temperature rise above 25 degrees Celsius shortens the reproductive phase by 6 per cent. Another staple crop, paddy, is also adversely affected due to excessive heat, rains and heavy winds.

In August 2022, Punjab, Haryana and Uttarakhand witnessed the spread of the dwarf virus in paddy. High temperatures in May and June were among the likely reasons for the spread of the disease.

Excessive rains during the flowering season also affect the shine of the paddy grain. This, in turn, affects the pollination process, resulting in little to no seeds.

Heat stress can also trigger early or delayed flowering. High-temperature stress before seeds reach physiological maturity can reduce germination by inhibiting the ability of the plant to supply the assimilates necessary for the germination process.

Agricultural scientists consider improved seeds and varieties adapted to regions with different agricultural climates as an effective solution to the problem.

This is the reason disease- and climate- resilient varieties have been developed in the last few decades. In February 2023, IARI registered a new heatwave-resistant wheat variety, HD3385, which was being tested at multiple locations in the rabi season.

Still, convincing the farmers to use the new seeds has been a persisting challenge. The IPCC Synthesis Report, released on March 20, also says that the rate of rise in agricultural productivity has declined over the past 50 years due to climate change, with “related negative impacts mainly in mid- and low-latitude regions”.

Since this region includes vast parts of India, the country must ensure that its agricultural productivity, which depends on seeds, remains intact.