Know more

So far, our research on the effect of light quantity has shown correlations between the effect of light intensity on bud break and the levels of sugars and cytokinins, two stimulators of bud break (Roman et al., 2016; Corot et al., 2017). We have experimentally demonstrated an effective role of cytokinins in this regulation. Local light in the vicinity of the bud stimulates cytokinin production in the stem, which allows bud break. On the other hand, the effective role of sugars has not yet been established because of the difficulty to manipulate them at the plant level. Our current research aims at using a model of sugar management by the plant and of the response of the bud to its local environment to understand the relative contribution of sugars and cytokinins. More recently, we have also undertaken to study the effect of light quality on branching in interaction with genotype. Initial results showed a strong genotype x light quality interaction, as previously demonstrated for other environmental factors, such as water supply (Crespel et al., 2014, 2020; Li-Marchetti et al. (2015). Year-specific QTLs (Quantitative Trait Loci) - co-localizing with BRC1 - have been identified (Li-Marchetti et al. 2017). They would be at the origin of the genotype x year interactions observed in rose.