Sorghum Hybrid Parents Research at ICRISAT–Strategies, Status, and Impacts

Sorghum (Sorghum bicolor L. Moench) is the first self-pollinated cereal staple crop, wherein heterosis has been commercially exploited to improve its productivity. Although the heterosis was demonstrated as early as 1927 in sorghum (Conner and Karper 1927), its commercial exploitation was possible only after the discovery of a stable and heritable cytoplasmic-nuclear male-sterility (CMS) mechanism (Stephens and Holland 1954). This CMS system has been designated as A1 (milo). Since then a large number of hybrids have been developed and released/marketed for commercial cultivation in Asia, the Americas, Australia and Africa. The hybrids have contributed significantly to increased grain and forage yields in several countries. The grain productivity increased by 47% in China and by 50% in India from the 1960s to the 1990s (FAO 1960–1996), which corresponds well with the adoption of hybrids in these countries. Adoption of the first commercial hybrid (CSH 1) in India over much of the rainy season sorghum area, while local varieties are confined to fairly narrow specific environmental niches stands testimony to the wide adaptability of hybrids over varieties (House et al. 1997). Currently, over 95% of the sorghum area is planted to the hybrids in USA, Australia and China. In India, over 85% of the rainy season sorghum area is planted to hybrids