Evolution of Plant Secondary Metabolites

Kliebenstein Lab

UC Davis Plant Sciences

Natural Variation of

Botrytis cinerea/Vitis Interactions


We are studying how the conversion of vineyards to either Organic or Biodynamic farming practices changes the microbe community. Specifically, we want to test if the changing microbe community decreases pathogenic fungal growth, i.e. Botrytis cinerea.

Project Summary

· There is variation in Botrytis Resistance among Grape Varietals.

· There is variation in Botrytis virulence on given varietals.

· Some Saccharomyces cerevisae appear to be able to inhibit Botrytis growth.

· There is a difference in the microbes present on organic and non-organic grape clusters.

Botrytis cinerea is a pest on the majority of grape varietals. Except when the goal is to make a “Botrytized” desert wine. There is evidence that Saccharomyces cerevisae and other yeasts can actually inhibit Botrytis germination and growth on developing grape clusters. In the past harvest season we have been collecting clusters from Organic/Biodynamic and traditional vineyards to look at the diversity of both the microbial community and the diversity of Botrytis in these samples.


A visual analysis of the microbial communities obtained from grapes showed that there was an increase in the complexity of the microbial community in Organic/Biodynamic vineyards in comparison to traditional vineyards. Further, there was a much lower level of pathogens such as Botrytis and Aspergilums. In addition, we identified Yeasts that appeared to inhibit the growth of Botrytis. We hope to expand these studies to utilizing DNA technologies to investigate microbial diversity as well as identify how Yeast can inhibit Botrytis.


We also looked at Botrytis diversity and found that there was genetic variation at the level of cluster, vineyard and region. This suggests that most clusters are actually infected by multiple Botrytis and that a vineyard will have a high level of Botrytis genotypes. We hope to utilize both DNA sequencing and fungicidal resistance to quantify this level of variation and compare Organic/Biodynamic vineyards to traditional vineyards.

Variation in Botrytis Resistance Among Grape Varietals

To contact us:

Phone: 530-754-7775
Fax: 530-752-9569