In a phenomenal move that will aid the breeding of more productive peanut varieties, a team of global researchers have traced the genes of peanuts to Bolivia. The latest discovery by the International Peanut Genome Initiative (IPGI) led by the University of Georgia, of which an Indian scientist was a member, will lead to better peanut varieties with enhanced pod and oil yield. It will also increase the crop's resistance to disease and help it sustain conditions of drought and excessive heat, thereby impacting the livelihoods of smallholder farmers positively, particularly those living in the marginal environments of Asia and sub-Saharan Africa.
The high quality sequencing of the ancestral genomes of the crop revealed it originated from a wild plant from Bolivia, which is a “living relic” of the prehistoric origins of the cultivated peanut species. The new peanut genome sequence will be available to researchers and plant breeders round the world to aid in the breeding of more productive peanut varieties. The study gives vital clues on how the sequence can be useful to crop improvement for sustainable and resilient peanut production.
This research will also help peanut farmers to tackle the emerging challenges of climate change better. The genome map can also be used to harness genetic diversity by broadening the genetic base of cultivated peanut genepool.
The peanut that is grown by farmers today is the result of hybridisation between these two wild species. The hybrid was cultivated by ancient inhabitants of South America. Because its ancestors were two different species, today’s peanut is a tetraploid, meaning it carries two separate genomes which are designated A and B sub-genomes. Comparisons of the DNA sequences of one of the wild species and the cultivated peanut showed that they are almost exactly the same.
“It’s almost as if we had travelled back in time and sampled the same plant that gave rise to cultivated peanuts from the gardens of these ancient people,” said David Bertioli, IPGI plant geneticist of the Universidade de Brasília, who is the lead author of the paper and works at the University of Georgia. The study has been published online in “Nature Genetics (http://www.nature.com/ng/journal/vaop/ncurrent/full/ng.3517.html)”— the leading high impact factor journal in the area of genetics, genomics, and biotechnology on Monday.
“Improving peanut varieties to be more drought, insect and disease resistant using the genome sequence, can help farmers in developing nations produce more peanuts with fewer pesticides and other chemicals and help these farmers feed their families and build more-secure livelihoods,” said Dr Rajeev Varshney, Research Program Director – Grain Legumes and the lead scientist from ICRISAT to participate in the IPGI.
To map the peanut’s genome structure, IPGI researchers sequenced the two ancestral parents, because together they represent the cultivated peanut. The sequences provide researchers access to 96% of all peanut genes in their genomic context.
The IPGI, is a multi-national group of crop geneticists working in cooperation for several years with 39 scientists from 26 organisations in six countries, including the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT). ICRISAT was involved in project planning, defining the strategy and also contributed to data analysis for the discovery.