Wor l d sorghum product ion was approximately 54 million t from 44 million ha in 1995.Developing countries account for roughly 9 0% of t h e area and 70% of product ion. In Asia about 15 million t ar e produced annually from about 14.1 million ha (FAO 1996) .Sorghum i s grown in a wide range of environments,and encounters various biotic and abiotic stresses such as drought , low temperatures , Al + 3 toxicity, Striga, stemborer , shootfly, head bug, midge, grain mold, downy mildew, anthracnose, leaf blight , and
rust . Breeding for resistance to these stresses stabilizes yield levels and is a relatively inexpensive way t o protect t h e crop from t h e major yield constraints. With the discovery of cytoplasmic-nuclear male-sterility (Stephens and Holland 1954),hybrids became popular with farmers in USA, China, India, Austral ia, and Thai land. In recent years, the r e has been increasing international
collaboration on sorghum research.
ICRISAT aims t o develop high-yielding and diversified, broad-based genetic materials
(gene pools, varieties, and seed parents) wi t h resistance to various stresses, and thus
better serve the needs of collaborators and partners. This paper summarizes ICRISAT' s efforts in diversifying and improving male-sterile lines through a trait -
based breeding approach
