Risks of herbicide-resistant rice in India: A review

Herbicide-resistant (HR) rice has the potential to improve the efficiency of weed management and facilitate adoption of resource conservation technologies (RCTs) in India. However, several important risks associated with HR rice should be examined before its widespread adoption is encouraged. The greatest risk in the commercialization of HR crops is the potential for transfer of the gene conferring the HR trait to related wild and weedy relatives. This could lead to increased weediness or invasiveness. Gene transfer between cultivated and wild or weedy rice is known to occur and existing scientific literature confirms that HR genes can move from HR rice to wild and weedy relatives forming hybrids. The likelihood of such gene transfer is especially high in India, where cultivated rice and its relatives are sympatrically distributed and their flowering times overlap. Such gene flow can impact crop invasiveness, fitness of wild species, and the loss of native biodiversity. Additionally, HR rice may contribute to the problems of crop volunteers and evolution of herbicide resistance. Based on existing scientific literature, it appears that these risks are low, but that additional studies are needed to fully assess the potential adverse consequences of widespread adoption of HR rice in India.