Science News 07/11/2011

Decoding of the Arhar genome by Indian scientists

Pigeonpea is the second most important pulse crop of India. About 85% of this grain legume is produced and consumed in India

A group of thirty-one Indian scientists from ICAR Institutes, State Agricultural Universities and Banaras Hindu University, led by Prof. Nagendra Kumar Singh from ICAR’s National Research Centre on Plant Biotechnology at New Delhi have decoded the genome of ‘Arhar’, the second most important pulse crop of India. This is the first plant genome sequenced entirely through a network of Indian institutions and it will provide highly valuable resource for variety improvement of pigeonpea.

The genome of popular Arhar variety ‘Asha’ was assembled using long sequence reads of 454-FLX second generation sequencing technology resulting in 511 million base pairs of high quality genome sequence information. The scientists have identified 47,004 protein coding genes in the Arhar genome, of which 1,213 genes are for disease resistance and 152 genes for tolerance to drought, heat and salinity that make it a hardy crop. In contrast to soybean, Arhar has fewer number of genes for oil biosynthesis and larger number of genes for cellulose biosynthesis which make it an oil-free woody plant. The genome sequence was used to develop a large number of ‘Arhar’ DNA markers which were experimentally validated for high rate of variation among the pigeonpea varieties. These markers will be useful for DNA fingerprinting and diversity analysis of pigeonpea germplasm and molecular breeding applications.

Availability of the Arhar genome sequence will accelerate development of new varieties and hybrids with enhanced productivity by making use of germplasm resources, in a way similar to the rice genome experience.

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