A team of 51 scientists from nine institutes in China, India, the US and Australia, along with Hyderabad-based International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), have decoded the complete DNA sequence of the ancestor of the groundnut, the diploid A-genome (Arachis duranensis). A scientific breakthrough on the DNA sequencing of the groundnut promises the development of improved groundnut varieties with enhanced traits, such as increased pod and oil yield, drought and heat tolerance, and greater disease resistance.
According to David Bergvinson, director general, ICRISAT, the research will provide an efficient road map for sustainable and resilient groundnut production for improved livelihoods of farmers particularly in the marginal environments of Asia and sub-Saharan Africa. Other significant traits this could help develop include aflatoxin-free, nutrition-rich and allergen-free varieties. The breakthrough also provides insights into geocarpy — a unique reproductive process of the groundnut, oil biosynthesis and allergens. Groundnut is one of ICRISAT’s mandate crops, along with chickpea, pigeonpea, sorghum, pearl millet and finger millet.
ICRISAT led a global research partnership in decoding the genome sequence of pigeonpea in 2011, and of chickpea in 2013; it is currently leading the genome sequencing of pearl millet. These high-quality genome sequencing efforts have put ICRISAT among select advanced research institutes of the world.
“This study has not just provided the full genome sequence to help plant breeders across the globe to develop more productive and more resilient groundnut varieties in a faster manner, but also provides us an insight to geocarpy, a reproductive process where the flowers grown on the stem go inside the soil and pod formations occur,” Rajeev Varshney, co-coordinator of genome sequencing project and research programme director, genetic gains programme at ICRISAT, said.
The study presents the draft genome of the groundnut A genome progenitor containing 50,324 protein-coding gene models. Analysis of the complete DNA sequencing suggests that the groundnut lineage was affected by at least three sets of chromosomes since the origin of flowering plants or eudicots. The research expands the knowledge of understudied areas of plant biology and human impacts on plants and also offers millions of structural variations that can be used as genetic markers for the development of improved groundnut varieties through genomics-assisted breeding.
The novel genes identified are going to enhance crop productivity and quality and thereby increase farmer incomes, Trilochan Mohapatra, director general, Indian Council of Agricultural Research (ICAR), said. Rich in protein and edible oil, groundnut is central to the financial and nutritional well-being of hundreds of millions of farmers and consumers across India, China, Africa and South America, he said.
“In addition to the discovery of responsible genes for oil formation in seed and allergens affecting human health, genome sequencing has also provided genes and millions of genetic markers to accelerate development of superior groundnut varieties with high pod and oil yield, greater resistance/tolerance to biotic and abiotic stresses and other nutritional traits,” Manish K Pandey, scientist – groundnut genomics and lead author from ICRISAT on the research paper, said.