Correlation between indigenous Oenococcus oeni strain resistance and the presence of genetic markers.

This study reports on monitoring Oenococcus oeni intraspecific diversity evolution during winemaking. Three different wines were monitored. The proportion of O. oeni species was determined by species-specific PCR and O. oeni strains were distinguished by multiplex PCR-RAPD. Each strain was tested by PCR for 16 significant markers revealed by a previous genetic comparison between a strong oenological potential strain and one with poor oenological potential. Population levels and diversity changed according to winemaking stages, oenological practices and the chemical properties of the wine. In all situations, O. oeni was the best-adapted species. Within the O. oeni group, intraspecific strain diversity decreased and the malolactic fermentation was the result of the most resistant strains with the highest number of markers.