About this Research Topic
Gene flow can be a major source of genetic variation within populations. Gene flow is commonly observed between domesticated plant species and their wild relatives (CWR, “Crop Wild Relatives”) wherever they co-occur, including domestication centers, where the crops establish contact with the wild ancestor as the agricultural zones expand, but also outside those centers, in areas where the ancestor is absent but its wild relatives are present. As a result of this contact, introgression of genes from the crop into the CWR and vice-versa can occur, but the former is more important for the conservation of natural populations. In the context of species conservation, it could be associated with negative and positive effects, both for the CWR and for the crop.
The evolution of invasiveness (of aggressive weeds, the third element in the agricultural evolutionary dynamics, beside the crop and the CWR) or the genetic erosion and extinction of wild species by gene flooding are among the undesirable consequences of gene flow. As a special case of gene flow, gene contamination of CWR by genetically modified organisms stands out because transgenic crops have expanded their cultivated area in many countries in the last few decades, and the results of this contact can be very diverse. The potential benefits of managed gene flow in general may include increased genetic variation for species rescue and adaptation to global changes, notably for domesticated species. In the case of these species, CWR can be used as a germplasm reservoir to great advantage to crop breeding. Ecological resilience of ecosystems under a changing climate is likely to encompass both adaptation and plasticity in species. The patterns of adaptation and standing genetic variation within species are influenced by gene flow, which is impacted by the distribution and connectivity of populations.
In this Research Topic we aim to understand, at a neotropical scale, how natural populations of CWR are responding and will respond to the ever-increasing contact between them and their respective crops as a result of agricultural expansion. We would like to explore:
1) the efforts to detect crop gene (either from GMO or not) introgression into CWR and its phenotypic effects;
2) the possible ecological impact of introgression on elements of the ecosystem interacting with the CWR, such as interactions with herbivores and pollinators;
3) biogeographic studies of CWR, including niche prediction, both at present and in the future, taking into account climatic changes that could possibly alter the areas of sympatry among CWR and between CWR and their respective crop;
4) studies on the reproductive biology of the crosses between crops and their CWR, in relation to histology, incompatibility, genetics and pollination ecology; and other studies with a clear relation to gene flow between crop and CWR.
Keywords: domestication, evolutionary changes, crop wild relatives, weed races, introgression
Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.