Genome editing can be helpful for climate adaptation of crops, say scientists

Advocating genome editing, some scientists have said the target traits should be for genetic improvement of rice, wheat, pulses, oil seeds and even sugarcane to address the issues of climate adaptation of crops, optimisation of shrinking natural resources, and combating malnutrition.

For instance, genome editing of rice can be done for water use efficiency, nitrogen use efficiency, abiotic stress tolerance, grain quality and productivity or, for that matter, green gram in pulses can be genome edited for drought and heat tolerance.

The scientists have also said it is desired that emphasis will be given more to pulses and oilseed crops for raising productivity levels, improving nutritional quality and developing new varieties resistant to heat and drought stresses, pests and pathogens, to help reduce India's dependency on imports.

Genome editing allows modifications in an organism's native DNA at a pre-determined genomic locus in a precise and targeted manner. In many countries, genome-edited crops are treated as non-GMOs because of the absence of foreign DNA in the final product, i.e., the improved crop variety is foreign DNA-free.

The Centre recently exempted the SDN1 and SDN2 categories of genome edited crops from bio-safety assessment under the relevant rules of the Environment (Protection) Act, 1986.

Scientists K.C. Bansal from the National Academy of Agricultural Sciences, Viswanathan Chinnusamy from Indian Agricultural Research Institute (ICAR) and Kutubuddin A. Molla from ICAR National Rice Research Institute in their paper 'Genome editing: a boon for plant biologists, breeders and farmers' published on July 10 in Current Science said this is a real boon for Indian plant biologists and breeders to use genome editing tools for basic research in functional genomics and gene discovery as well as translational research for developing high-yielding crop varieties and hybrids to meet the modern day challenges.

Genome editing could generate new varieties, which require fewer inputs such as agrochemicals, water and fertilisers, and produce more output enabling the increase in farmers' income.

"The technology is beset with great potential for the next agricultural revolution, specifically by developing crops with desired traits for sustainable crop production. Genome editing has successfully generated crops with improved novel traits that were technically difficult through traditional breeding or genetic engineering," the scientists pointed out.

The availability of efficient genome engineering tools for precise editing would greatly help Indian agriculture by rapidly and accurately creating useful alleles directly in the elite crop varieties.

"While the Green Revolution resulted in self-sufficiency with regard to food production that enabled the government to enact the Right to Food Act, 2013 to feed millions of people, now is the time of greater concern to address the issues of climate adaptation of crops, producing more from the shrinking natural resources, increasing input use-efficiency and combating malnutrition," Bansal, the lead author, said.

According to the recent IPCC Sixth Assessment Report (AR6), India is one of the most economically stressed countries due to climate change.

Major emphasis is, therefore, needed for developing climate-ready crops combining field stress tolerance/resistance to abiotic and biotic stress factors with yield enhancement traits like improved photosynthesis, enhanced acquisition and use efficiency of water, nutrients and other natural resources to produce more with less and fewer inputs, the paper said.

It is desired that emphasis will be given more to pulses and oilseed crops for raising productivity levels, improving nutritional quality, and developing new varieties resistant to heat and drought stresses, pests, and pathogens, to help reduce India's dependency on imports.

"However, the unavailability of functionally characterized genes for these traits limits the application of genome editing. Hence, besides focusing on genome editing for product development, genome editing for gene discovery should be an important thrust area in these and other prioritized crops," the scientists pointed out.