ABSTRACT

Sorghum is the fi fth most important cereal grain in terms of production following maize, wheat, rice and barley (www.fao.org). Its cultivation is extensive in marginal rainfall areas of the tropics and subtropics throughout the world. This is due to its remarkable ability to produce a crop under adverse conditions. Some selected types are also grown in temperate regions. Worldwide, sorghum has attracted breeders’ attention as a rich source of proteins, vitamins and carbohydrates (Shiringan 2009), and a potential source of biofuel. Rapidly increasing populations coupled with global climatic trends, imply that “dryland” crops such as sorghum will be of increasing importance. Moreover, knowledge of the genetic control of perenniality in sorghum (Paterson et al. 1995b, 2008) and progress in functional genomics of perenniality (Kresovich et al. 2005) make sorghum a promising biofuels crop. S. halepense, one of the world’s noxious weeds, is an interspecifi c hybrid between S. bicolor (cultivated sorghum) and S. propinguum, a rhizomatous species. The hybrid provides resources to dissect the genetic basis of rhizomatousness (Peterson et al. 1995). Its noxious trait is desirable in many forages and turf plants, making sorghum a novel tool for understanding weed biology and for breeding a wide range of forage, turf and other annual or perennial cellulosic biomass plants.