Genetic Gains in Pearl Millet in India: Insights Into Historic Breeding Strategies and Future Perspective

Pearl millet (Pennisetum glaucum R. Br.) is an important staple and nutritious food crop in the semiarid and arid ecologies of South Asia (SA) and Sub-Saharan Africa (SSA). In view of climate change, depleting water resources, and widespread malnutrition, there is a need to accelerate the rate of genetic gains in pearl millet productivity. This review discusses past strategies and future approaches to accelerate genetic gains to meet future demand. Pearl millet breeding in India has historically evolved very comprehensively from open-pollinated varieties development to hybrid breeding. Availability of stable cytoplasmic male sterility system with adequate restorers and strategic use of genetic resources from India and SSA laid the strong foundation of hybrid breeding. Genetic and cytoplasmic diversification of hybrid parental lines, periodic replacement of hybrids, and breeding disease-resistant and stress-tolerant cultivars have been areas of very high priority. As a result, an annual yield increase of 4% has been realized in the last three decades. There is considerable scope to further accelerate the efforts on hybrid breeding for drought-prone areas in SA and SSA. Heterotic grouping of hybrid parental lines is essential to sustain long-term genetic gains. Time is now ripe for mainstreaming of the nutritional traits improvement in pearl millet breeding programs. New opportunities are emerging to improve the efficiency and precision of breeding. Development and application of high-throughput genomic tools, speed breeding, and precision phenotyping protocols need to be intensified to exploit a huge wealth of native genetic variation available in pearl millet to accelerate the genetic gains.

Automated summary

Pearl millet is a crucial staple and nutritious crop in semi-arid and arid regions of South Asia and Sub-Saharan Africa, with breeding efforts resulting in a 4% annual yield increase over the past three decades. Future focus should be on accelerating genetic gains through hybrid breeding and incorporating nutritional trait improvement into breeding programs. Expanding the use of high-throughput genomic tools, speed breeding, and precision phenotyping protocols can help exploit the wealth of genetic variation in pearl millet for faster genetic gains.