Correlated genetic effects on reproduction define a domestication syndrome in a forest tree

Abstract

Compared to natural selection, domestication implies a dramatic change in traits linked to fitness. A number of traits conferring fitness in the wild might be detrimental under domestication, and domesticated species typically differ from their ancestors in a set of traits known as the domestication syndrome. Specifically, trade-offs between growth and reproduction are well established across the tree of life. According to allocation theory, selection for growth rate is expected to indirectly alter life-history reproductive traits, diverting resources from reproduction to growth. Here we tested this hypothesis by examining the genetic change and correlated responses of reproductive traits as a result of selection for timber yield in the tree Pinus pinaster. Phenotypic selection was carried out in a natural population, and progenies from selected trees were compared with those of control trees in a common garden experiment. According to expectations, we detected a genetic change in important life-history traits due to selection. Specifically, threshold sizes for reproduction were much higher and reproductive investment relative to size significantly lower in the selected progenies just after a single artificial selection event. Our study helps to define the domestication syndrome in exploited forest trees and shows that changes affecting developmental pathways are relevant in domestication processes of long-lived plants.

Genetic variation in resistance of Norway spruce seedlings to damage by the pine weevil Hylobius abietis

“…First, breeding for productivity could have truncated the remaining variability in other functional traits such as resistance to pest and pathogens (Androsiuk et al 2012). Previous studies in pine trees have shown that even a single selection event on productivity traits can introduce measurable changes in other life functions (Santos-del-Blanco et al 2015). We do not know if this could be the case for our Norway spruce population, but there is ample evidence that this breeding populations retain high neutral genetic variation that covers most of the existing natural variation (Androsiuk et al 2012).…”

Reproductive modification in forest plantations: impacts on biodiversity and society

“…In maritime pine ( Pinus pinaster ), Santos‐del‐Blanco et al . () reported that a single cycle of selection for timber yield decreased the proportion of reproductive trees (51% in selected group vs 66% in control group), delayed the age and size at first reproduction, lowered the reproductive‐to‐vegetative allocation ratio, and affected the proportion of protandrous vs hermaphroditic individuals.…”

Ecological and association genetics in two Mediterranean pine species

“…Growth and flowering are also widely recognized key traits related to fitness in forest trees (e.g. Santos-del-Blanco et al 2015 for maritime pine). Phenotypic variation and its genetic basis for growth, wood quality and drought resistance traits have been broadly studied in pines (e.g.…”