Setting up new tools to reduce the duration of the grapevine breeding process : Mercier experience

Abstract

Context and purpose of the study

Since some years, the French wine sector faces strategical challenges, all linked to climate change. Multiple issues have been observed like diseases development, early frost, drought, change in the precocity and maturity of grapes, each one resulting in loss of productivity and yield. In France, the varieties proposed today by nurseries are historical varieties that are not well adapted to those changes. Therefore, Mercier Frères, one of the leading grapevine nursery, has decided to start its own research programs, with the help of its laboratory Novatech, to answer the growing demand for new grapevine varieties.

Discussion

The NATHY program (“Naturellement Résistant”) consist in creating new varieties by traditional breeding, with the help of molecular tools and new production techniques. In partnership with breeders around the world, the first aim is to develop and propose resistant varieties first to the most harmful fungi: downy and powdery mildew, and black rot. Traditional breeding of perennial species like grapevine can take 25 to 30 years. The challenge for the company is to reach a breeding cycle of 10 years from the seed to the registration of the variety. To achieve this goal, the combination of multiple tools is required. Marker assisted selection allows us to detect resistance genes in the early life of the plant, and to discard rapidly genotypes that don’t meet our expectations. Another major improvement is to reduce the time for scion production. A tomato-like production system has been developed, enabling the plant to produce scions in only one year after planting, instead of 3 years in a classic field process. Multiple other tools are tested to study all the ways to reduce the breeding cycle. With this rupture innovation program, we hope to create new genetic resources meeting growers’ expectations about climate change challenges.