Submitted to: Book Chapter
Publication Type: Book / chapter
Publication Acceptance Date: 9/15/2005
Publication Date: 12/15/2005
Citation: Jauhar, P.P., Rai, K.N., Ozias-Akins, P., Chen, Z., Hanna, W.W. 2005. Genetic improvement of pearl millet for grain and forage production: cytogenetic manipulation and heterosis breeding. (book chapter in CRC Press). Genetic Resources, Chromosome Engineering, and Crop Improvement. CRC Press, Boca Raton, FL, pp. 281-307. Interpretive Summary: Pearl millet is an important cereal crop grown primarily in Asia and Africa, where it is grown on some of the poorest soils and sustains a large proportion of the impoverished population. It is the sixth most important cereal crop in the world, following wheat, rice, maize, barley, and sorghum. Pearl millet is the only cereal that reliably provides grain for human consumption and fodder for cattle even on poor, sandy soils under hot, dry conditions. Although pearl millet is of great agricultural importance and is a very favorable organism for cytogenetic and molecular studies, it has not received the attention it deserve s. Its protogynous flowering (emergence of female parts before anthers) makes it suitable for producing hybrids and for crossing it with other species. Numerous high-yielding grain hybrids are under cultivation mostly in Asian countries - specifically in India, resulting in phenomenal increase in grain yields. Apomixis is a reproductive mechanism that helps clone plants through seeds and to produce carbon copies. Attempts are being made to introduce apomixis in hybrids that would help perpetuate hybrid vigor without having to produce hybrid seed year after year for distribution to farmers. The information in this article will help pearl millet geneticists and breeders in planning strategies for its improvement so that it may continue to play in an important role in the welfare of the poor in Africa, Asia, and Latin America.
Technical Abstract: Pearl millet, Pennisetum glaucum (L.) R. Brown, is a dual-purpose cereal grown for grain and green fodder on about 27 million hectares primarily in Asia and Africa, where as poor man's major source of dietary energy, it sustains a large proportion of the population. In terms of annual production, pearl millet is the sixth most important cereal crop in the world, following wheat, rice, maize, barley, and sorghum. Because of its low chromosome number (2n = 14) and other karyotypic features, pearl millet offers a particularly favorable organism for basic cytogenetic studies, aneuploid analysis and elucidation of its cytogenetic architecture. Its protogynous flowers and outbreeding system make it ideal for heterosis breeding and interspecific hybridization. The purpose of this article is to review recent information on the cytogenetics and breeding of pearl millet with particular reference to strategies for heterosis breeding. Numerous grain hybrids are already under cultivation in Asia and have substantially raised the grain yield levels. Exploitation of hybrid vigor will continue to be an important strategy for improving both grain and forage yields. If apomixis could be introduced in superior grain hybrids with the right gene combinations, it would be possible to perpetuate hybrid vigor over extended periods without having to produce hybrid seed every year for distribution to farmers. The information in this article will be useful to researchers in classical and molecular cytogenetics as well as to practical plant breeders involved in pearl millet improvement.