Reproductive Biology, Genetics, Evolution, and Diversity in Finger Millet (Eleusine coracana (L.) Gaertn.)

Finger millet (Eleusine coracana (L.) Gaertn.) is a nutrient-dense climate-resilient major grain crop in Asian and African subcontinents. Being future smart food crop, its production will help in improving the livelihood of people by improving nutritional status. Thus, it is essential to understand its floral biology, genetics, origin, evolution, and genetic diversity to achieve the goal of nutritional security in the developing countries. The origin of finger millet traced back to 5000 years, and Africa and India were recognized as the primary and secondary centers of diversity. Finger millet is a highly self-pollinated allotetraploid crop with as low as 1% cross-pollination aided by wind; thus, artificial hybridization techniques can permit its further improvement immensely. Identification of modern emasculation techniques like chemically hybridizing agent (ethrel), hot water emasculation, cold water, and plastic bag method transformed from traditional to modern production system due to complex architecture and tiny nature of florets of finger millet. Study of genetic diversity for identification of resistance against various biotic and abiotic stresses as well as high calcium, zinc, and iron-containing species helps in classification and improving the overall production aspect of finger millet. Thus, it is vital to preserve the germplasm for the conservation of genetic diversity and understanding the crop in-depth. This chapter discusses the details about finger millet origin, evolution, floral biology, and cytogenetics, and genetic diversity also highlights the germplasm for overall improvement of finger millet.