ICAR develops wheat that can beat the heat

ICAR develops wheat that can beat the heat

Subject :Science and Technology

Section :Biotechnology

Context: Last year in March, the temperature increases above normal conditions results into the damage of crops specially wheat, at a time when the grains were accumulating starch and proteins; leading to a significant drop in output as well as government procurement.

More in news:

• Keeping previous year’s damage in view, the Agriculture ministry has set-up a committee to monitor the situation arising from the increase in temperatures and its impact, if any, on the current wheat crop.
• This year, the temperatures are already 3-5 degrees Celsius above normal in many wheat-growing areas.

Probable solution of India’s crop vulnerability due to terminal heat stress:

• Indian Council of Agricultural Research (ICAR) has suggested to advance the time of sowing.
  • Wheat is a typically a 140-145 days crop planted mostly in November – before the middle of the month in Punjab, Haryana, Rajasthan and Madhya Pradesh (post the harvesting of paddy, cotton and soyabean) and the second half and beyond in Uttar Pradesh and Bihar (after sugarcane and paddy).
  • If sowing can be preponed and taken up from around October 20, the crop isn’t exposed to terminal heat, with much of the grain-filling being completed by around the third week of March.
  • It can, then, be comfortably harvested by the month-end.
• Issue: wheat sown before early-November is also prone to premature flowering.
  • The crop seeded in the first half of November normally takes 80-95 days to come to heading (i.e. for the ‘baali’, or earheads bearing the flowers and eventually grain, to fully emerge from the wheat tillers).
  • But if we sow in October, heading is cut short by 10-20 days and occurs in 70-75 days. This affects yields, as the crop does not get enough time for vegetative growth (of roots, stems and leaves).

New varieties developed by IARI:

• The IARI scientists have developed three varieties, all of them incorporating genes that are responsible for the “mild vernalisation requirement” preventing premature flowering and early heading.
  • Mild vernalisation requirement is the need for a certain minimum period of low winter temperatures for initiation of flowering.

1. HDCSW-18: It was released and officially notified in It has a Higher yield and its plants are taller than the normal varieties, which made them prone to lodging or bending over when their earheads were heavy with well-filled grains.
2. HD-3410: It was released in 2022, has higher yield potential (7.5 tonnes/hectare) with lower plant height (100-105 cm).
3. HD-3385: Most promising among the three. With the same yields as HD-3410, plant height of just 95 cm and strong stems, it is least lodging-prone and most amenable for early sowing.
   • IARI has registered HD-3385 with the Protection of Plant Varieties and Farmers’ Rights Authority (PPVFRA). It has also licenced the variety to the DCM Shriram Ltd-owned Bioseed for undertaking multi-location trials and seed multiplication.

Merits of these wheat varieties:

• Longer window for grain development
• Longer period for vegetative stage growth between germination and flowering
• Able to accumulate more biomass along with grain weight