Pearl millet (Pennisetum glaucum) is extremely important as a major grain staple and as animal feed in some of the driest areas of Asia and Africa. Grown primarily by smallholder farmers in marginal areas under rain-fed conditions, improving yields and resistance to drought and disease through modern breeding is important to millions of livelihoods. New hybrids have been developed that offer higher yields, but also greater vulnerability to certain diseases. In India, pearl millet is grown on 9 million hectares of which 70% are planted with hybrid cultivars. Since pearl millet hybrids first reached farmers’ fields in India in the late 1960s, each of the hybrid varieties grown have been attacked by a downy mildew plant disease that can result in up to 80% crop loss.
From 1999-2002, the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) with the John Innes Centre and the Plant Sciences Research Programme of the Department for International Development (DFID) developed biotechnological solutions to help reduce the incidence of this disease in hybrid cultivars. After mapping the genomic regions of pearl millet that control downy mildew resistance, straw yield potential, and grain and straw yield under drought stress conditions, breeders used conventional breeding and marker-aided selection (MAS) to transfer several genomic regions with improved downy mildew resistance to 2 parental lines of popular hybrid millet. MAS was then used to derive 2 new varieties – ICMR 01004 and ICMR 01007 – with 2 different gene blocks for downy mildew resistance. In trials, these varieties have had grain and straw yields equal to or better than their parent lines whilst showing a vast improvement in their resistance to downy mildew.