A focus on the implication of genotype by environment interaction on carotenoid accumulation

International audienceConditioned both by environment, genotype and the interaction of the genotype itself with the environment, some phenotypic plasticity lies between individuals. This phenomenon allows an adaptive potential of individuals, and may depend on various mechanisms as overdominance, epistasis, pleiotropy, gene linkage and epigenetics. Depending on studied characters, some genotypes or cultivars may be more and less plastic and, in some cases, more and less stable. Considered as powerful anti-oxidants, carotenoids have large applications in medical fields as cancer preventive compounds and precursors of vitamin A and there is an interest for guaranteed carotenoid content in crops. Even if carotenoid accumulation seems to depend on a high genetic component for climacteric fruits as tomato, there is a large effect of G×E interaction overall. Thus, the genetic determinism alone does not explain carotenoid accumulation among most vegetables. Carrot is depicted as a healthy vegetable, thanks to its ability to accumulate carotenoids at high level in roots. However a large variation is observed. In spite of a well-known carotenoid biosynthesis pathway and recent progress on the genetic control, carotenoid accumulation in an underground reserve tissue remains unclear. Regulation can occur at several scales and can result from environmental influences. This article deals with the implication of genotype by environment interaction on carotenoid accumulation and the underlying mechanisms