Abstract. Grape (Vitis vinifera L.) is a major agricultural crop with significant economic value
worldwide, including Azerbaijan. Grapevines in Azerbaijan face significant challenges from downy
mildew (Plasmopara viticola), a fungal disease that affects grape yield and quality. This study aimed
to evaluate the resistance of 37 grapevine varieties to downy mildew under natural field conditions.
The results revealed two main genotype clusters: 13 varieties were classified as tolerant (scoring
3-3.5), while 24 varieties were classified as susceptible (scoring 4-4.5). No varieties were found to
be highly resistant or highly susceptible. The evaluation process utilized a 5-point scale to assess
disease severity on leaves and clusters. Findings from this study are crucial for identifying grapevine
varieties with improved resistance to downy mildew, aiding in the development of more resilient
grape cultivars. These results have significant practical implications for enhancing grapevine
production and mitigating the impacts of fungal diseases in viticulture.
Acta Botanica Caucasica от Бакинского государственного университета распространяется по лицензии CC BY 4.0
