Application of Markers Assisted Selection for Striga Hermonthica Resistance on Sorghum (Sorghum bicolor (L.) Moench

Abstract

Sorghum (Sorghum bicolor L. [Moench]) is a staple food crop for smallholder farmers in arid and semi-arid(ASALs) regions worldwide, feeding over 500 million of the world's most resource-poor. Development of Striga Hermonthica resistant cultivars by conventional breeding is slow and have been hampered by the lack of efficient and reliable screening techniques in breeding programs. Molecular markers that are linked to witchweed resistance can expedite the development of resistant cultivars through the adoption of appropriate marker-assisted selection (MAS) strategies. Marker-assisted selection involves the selection of genotypes carrying a desirable gene(s) via linked markers; through MAS more rapid transfer of traits from donor parents to more elite locally adapted crop cultivars is possible with simple-sequence repeat (SSR) markers which have been initially used to detect polymorphism between the parent cultivars. Although costly to develop relative to some other classes of genetic markers, once developed, analysis by SSR markers is both easy and inexpensive. The highly polymorphic nature (high information content) and other favorable characteristics make them excellent genetic markers for a number of studies including marker-assisted selection and fingerprinting of germplasm collections. In this review, we summarize the molecular markers that are linked to the inheritance trait or low germination stimulant production is one of the recognized mechanisms of witch weed resistance.