If distance from the site did not show long-term negative effects, how would genes from populations located closer to the damaged site but from a contrasting environment affect local plant populations? When local plants were crossed with plants from a nearby, but much drier, site, seedling performance in the first and second generation of progeny was much worse than in the distant crosses.
Although the study is relatively small scale, three generations of offspring were followed, which is relevant for assessing long-term consequences of introducing new genes to populations. The authors conclude that when new, foreign genes are introduced to a damaged site, the neighboring populations may experience initial negative effects; however, over time, as long as the populations do not experience additional foreign gene input, the negative effects may diminish and the maladapted foreign genes will decrease. Moreover, when selecting seeds or plants for re-vegetating damaged sites, it may be more important to match up habitat types or environments than be concerned with distance per se.
"More research on the long-term effects of gene flow introduced into local populations and their consequences for population persistence in widespread and rare plant species is needed to determinate the generality of these findings," said Crmieux.
|Contact: Richard Hund|
American Journal of Botany