Genetic and evolutionary effects of hybridization-introgression and their implications for conservation of crop wild relative species

Genetic diversity in crop wild relatives (CWRs) includes important germplasm resources that play essential roles in crop genetic improvement. Efficient conservation and sustainable utilization of CWRs is critical to world food security. Severe habitat damage presents a major challenge to CWR survival, with many CWR populations consequently endangered or even extirpated. In addition, a neglected factor threatening the long-term CWR availability is the flow and introgression of crop alleles into CWR populations; these processes may considerably alter CWR genetic structure and integrity, leading to genetic diversity losses in in situ conserved CWR populations. Little is known, however, concerning the impacts of crop-wild gene flow and introgression on CWR conservation. The design of effective strategies, although challenging, is important to minimize the unfavorable consequences of these processes on CWR conservation.