Improvement of Sorghum through Transgenic Technology

Sorghum is the fifth most important cereal crop in the world. It is largely grown on marginal soils with residual moisture where other major cereals cannot be grown due to inadequate water. Sorghum is a multipurpose crop and the species shows great diversity. For a large part of Asia and Africa, sorghum’s grain is used as food and its stalk as fodder and feed. In rest of the world, sorghum is considered as forage crop and also as stock for ethanol production. Sorghum yield has been substantially increased through conventional breeding in India. However, resistance to abiotic stresses and biotic stresses such as shoot fly, stem borer, grain mold, and charcoal rot is limited due to inadequate genetic resources that can be readily used in crop improvement programs. Therefore, genetic engineering technology can assist the production of agronomically desirable crops that exhibit increased resistance to pests, pathogens, and environmental stress and enhancement of nutritional qualities. Sorghum research has received less attention compared to other cereals for adoption of modern molecular tools, and very few laboratories in the world are addressing sorghum crop improvement programs through novel methods. Extensive research has been focused on other cereal crops, and a number of genes conferring agronomic advantages have been introduced through Agrobacterium and particle bombardment. In this article, we present the current status, progress, and prospects in transgenic sorghum technology and future approaches to increase its economic value, thereby providing monetary benefits to sorghum farmers. Sorghum Transformation The first report of the successful transformation of sorghum appeared as early as the 1990s. Yet, sorghum is considered to b