January 20, 2026 08:53 AM IST First published on: Jan 20, 2026 at 08:53 AM ISTWeeds are a known threat to agricultural produce, growing at their expense by competing with them for nutrients, water and sunlight. Most of these unwanted plants are above the ground, making them amenable to manual removal. The problem is with weeds that attach to the roots of plants. By the time their shoots come out and are visible, the damage is done. Mustard farmers in Rajasthan and Haryana are now facing this with Orobanche aegyptiaca, a root parasitic weed that has become a major “hidden” threat to India’s biggest edible oil crop.The problem highlights the need for agricultural R&D as an imperative for the country’s food security. The urgency is even more in the context of climate change and the emergence of new pathogens and weeds. If weeds cannot be removed by hand, and with labour becoming scarce, more efforts are required at breeding varieties or hybrids that can “tolerate” the application of herbicides. The Indian Agricultural Research Institute and Savannah Seeds have developed rice containing a mutated ALS gene, whose altered DNA sequence allows farmers to spray imazethapyr, a broad-spectrum herbicide that kills weeds without harming the standing crop. Mahyco has done the same for wheat, while some mustard farmers have planted a hybrid of Corteva Agriscience that can tolerate two other herbicides, imazapyr and imazapic. Whether this can control Orobanche remains to be seen. In all these cases, the herbicide-tolerance trait has been introduced through mutation breeding, not genetic modification (GM).AdvertisementThe Centre has done well to permit the commercial cultivation of non-GM herbicide-tolerant and gene-edited crops. But it mustn’t close the door on GM. Delhi University scientists have developed GM mustard lines incorporating a foreign ‘cp4 epsps’ and a double-mutant ALS gene conferring tolerance to different herbicides. The potential for using several herbicides can address the resistance that can build up to a single molecule because of continuous application. Agriculture is too important a sector to not try out new technologies — or at least test their efficacy and biosafety through large-scale field trials.