Breeding for Striga Resistance in Sorghum: Exploitation of an Intricate Host–Parasite Biology

ABSTRACTThe parasitic weed Striga Lour. has been one of the more intractable agricultural problems seriously limiting productivity of cereal and legume crops in sub‐Saharan Africa. The development of crop plants with resistance to Striga has been limited because of the complexity of interactions between host, parasite, and the physical environment. We formulated a novel approach based on developing and exploiting a thorough understanding of the biology of this intricate association. We employed this knowledge‐based approach to develop powerful selection assays, to conduct genetic analyses, and to characterize the range of mechanism involved in host plant resistance to Striga Information thus generated has been used to identify unique sources of resistance to Striga, introgress these genes into selected cultivars, and deploy sorghum [Sorghum bicolor (L.) Moench] cultivars with known sources of Striga resistance either independently or in tandem as genotypes with multiple mechanisms of resistance. High yielding sorghum cultivars with Striga resistance and evident grain quality characteristics have been developed and deployed in a number of African countries to be used as cultivars per se or as a central component of an integrated Striga management program.