Gene Flow and Introgression from Domesticated Plants into their Wild Relatives

TLDR

Domesticated plant taxa are not evolutionarily discrete from their wild relatives, and most mate with wild relatives worldwide, potentially influencing wild population evolution through gene flow. The study uses population genetic theory to predict the evolutionary consequences of crop‑to‑wild gene flow and to discuss its applied impacts on aggressive weed evolution and rare species extinction. The authors suggest methods for assessing the likelihood of hybridization, introgression, and the potential for undesirable gene flow from crops into weeds or rare species. A literature review of the world’s 13 most important food crops shows that 12 of them hybridize with wild relatives in some part of their agricultural distribution.

Abstract

▪ Abstract Domesticated plant taxa cannot be regarded as evolutionarily discrete from their wild relatives. Most domesticated plant taxa mate with wild relatives somewhere in the world, and gene flow from crop taxa may have a substantial impact on the evolution of wild populations. In a literature review of the world's 13 most important food crops, we show that 12 of these crops hybridize with wild relatives in some part of their agricultural distribution. We use population genetic theory to predict the evolutionary consequences of gene flow from crops to wild plants and discuss two applied consequences of crop-to-wild gene flow–the evolution of aggressive weeds and the extinction of rare species. We suggest ways of assessing the likelihood of hybridization, introgression, and the potential for undesirable gene flow from crops into weeds or rare species.