Scientists found that its sequence was comparable in size to that of the human genome
Peanuts address nutritional demands in underdeveloped countries as they are a rich source of proteins and fatty acids.In a significant development, an international team of researchers led by plant geneticistsat the Hyderabad-based International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) has decoded thecomplete set of chromosomes of two widely cultivated peanut varieties belonging to the subspecies hypogaea and fastigiata.
Genetic decoding — known as the reference genome sequence — helps in understanding cell-level mechanisms which make one variety score better than the other. For peanuts, the deciding factors are high oil and protein content, disease and heat resistance and high yield.
The gene sequencing is a complex and exhaustive process running in to many years. The process involves several stages: high-quality DNA is isolated from the target plant and cut into bits. It is then placed in a sequencing machine.With the helpof special tools and bioinformatics programs, gene sequencing is synthesised.
Peanuts, with their farming history of more than 6,000 years have complex genomes. In this study, the scientists found that its sequence was comparable in size to that of the human genome which had a little over 3 billion DNA base pairs with 83,709 genes that control its traits.
During this process, the team discovered that the peanut variety was a tetraploid — which means that the cultivated groundnut genome is home to two different sub-species genomes. They also found that the exchange of genomes was occurring with one dominating the other.
“The tetraploid natureis the result of natural hybridisation (crossing) of two wild species called Arachisduranesnis and Arachisipaensis. The cultivated peanut genome is home to both the genomes of the sub-species. By living and coordinating together, this dual diploid genome decides the quality of crops we see in the fields,” explained Rajeev Varshney, Research Program Director at ICRISAT, while speaking to India Science Wire.
Genome referencing provides researchers access to all the peanut genes, which, in turn, will boost gene discovery and marker development studies.“It will accelerate development of superior peanut varieties with high pod and oil yield, greater resistance to diseases, nutrition-rich, aflatoxin-free, and improved oil quality seeds,” added Manish Pandey, senior scientist at ICRISAT.
This study will help expand genetic base for sustainable and resilient groundnut production to face the challenges brought about byof climate changes.
The study involved scientists from research institutes in China, Taiwan, Australia, USA, Argentina, Brazil, Japan, France and Korea, besides India. The research was published in two papers inthe journal Nature Genetics.The Indian team included Manish K Pandey, Rajeev K Varshney, Vanika Garg, Amir W Khan, Prasad Bajaj and Annapurna Chitikineni (ICRISAT); Polavarapu Bilhan Kavikishor (Osmania University) and Senjuti Sinharoy (National Institute of Plant Genome Research, New Delhi).
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.