Eclipse

Red-fleshed apple varieties are becoming increasingly popular with consumers. The red pigmentation of the flesh is due to the accumulation of pigments, anthocyanins which have beneficial effects on human health thanks to their antioxidant and anti-cancer properties.

Today, the anthocyanin biosynthetic pathway and its regulation by transcription factors (MYB) are well characterized. In addition, genetic and epigenetic factors have been identified as involved in the control of the metabolic pathway, and the expression of several genes can be influenced by agro-climatic factors such as water stress, heat stress or variations in the light environment.

The multiplication and testing of new red-fleshed apple varieties in many contrasting environments have recently led to the observation of remarkably diverse fruit color phenotypes. In this context, my thesis project is the study of the effects of agro-climatic factors on the red-flesh phenotype in several genotypes during their development and ripening. My work has two focuses: a multifactorial study with no apriori analysis of 6 genotypes in contrasting environments, and a second focus on analyzing the effect of two major agro-climatic factors, radiation and drought, on a red-fleshed apple genotype.

All these experiments will enable us to gain a better understanding of the mechanisms controlling anthocyanin production, and to determine the involvement of epigenetic processes in response to stress. But they will also enable us to develop simple levers to increase the anthocyanin content of fruit and better manage orchards in a context of climate change.

VALEMA's  supervisors : Jean-Marc Celton et Anne-Laure Fanciullino