Pigeonpea (also known as tropical green pea or toor dal), once referred to as an ‘orphan crop’ mainly grown by poor farmers, is now all set to join the world’s league of major food crops with the completion of its genome sequence.
Years of genome analysis by a research partnership between Indian and Chinese scientists, led by the International Crops Research Institute for the Semi-Arid Tropics (Icrisat), Hyderabad, has resulted in the identification of 48,680 pigeonpea genes, setting the pace for development of improved variety of the pulse in future.
A couple of hundreds of these genes were found unique to the crop in terms of drought tolerance, an important trait that can be transferred to other similar crops like soybean, cowpea (also called black-eyed pea) or common bean that belong to the same family.
“The mapping of the pigeonpea genome is a breakthrough that could not have come at a better time. Now that the world is faced with hunger and famine, particularly in the Horn of Africa brought about by the worst drought of the decades, science-based, sustainable agricultural development solutions are vital in extricating vulnerable dryland communities out of poverty and hunger for good,” said Icrisat director-general William D Dar.
Grown on about 5 million hectare in Asia, sub-Saharan Africa and South-Central America, Pigeonpea is a very important food legume for millions of the poor in the semi-arid regions of the world. Known as the ‘poor people’s meat’ because of its high protein content, it provides a well-balanced diet when accompanied with cereals.
India is the largest producer of pigeonpea, accounting for 85 per cent of the world’s total produce of around 3.25 million tonne. However, crop productivity in the country as well as in sub-Saharan Africa is only less than 1 tonne per hectare. An improved understanding of the pigeonpea genome will have a major impact on improved crop productivity, tackling pests and disease constraints in production, and improved resistance to harsh environments and the future variable climate.
In a press release on Monday, Dar said modern crop improvement technologies for smallholder farm crops such as pigeonpea would be crucial to speed up the development of improved varieties that can provide high yields and improved livelihoods, and at the same time meet the challenges of marginal environments and the threat to climate change and scarce natural resources.
Scientists worked on this project represented Icrisat, Hyderabad, CGIAR Generation Challenge Programme (GCP) and Beijing Genomics Institute (BGI, Shenzhen, China).
Pigeonpea is the first ‘orphan crop’, the first ‘non-industrial crop’ and the second food legume (after soybean) with a completed genome sequence. The complete genome sequence of pigeonpea was featured as an advance online publication on the website of the journal – Natural Biotechnology – on November 6.
According to lead scientist and coordinator for the pigeonpea genome sequencing project, Rajeev Varshney, having the pigeonpea genome sequence as a reference would significantly speed up and reduce the cost of screening the ‘good genes’ within the stored pigeonpea seed collections in genebanks like that of Icrisat.
“This also means dramatically reducing the cost of developing new improved varieties for farmers. At the moment, in general, it can take 6-10 years to breed a new variety. With the use of this genome sequence data, in the future, we could be breeding a new variety in just about 3 years.” Varshney said.
