An official website of the United States government.
Trunk diseases (Eutypa dieback, Botryosphaeria canker, Esca, Petri disease) cause significant impacts to yield and vineyard longevity in established growing regions of the US, and the increasing rate of detections of the same pathogens in young regions makes it clear that ignoring the threat of such diseases is a risk to the national industry. With no eradicative controls, prevention is essential, but prevention is more challenging today, as the fungicide used to prevent infection (benomyl) was taken off the market in 2001, and its replacement (Topsin) is only available in three states. Topsin applications are labor-intensive and do not improve longevity of infected vineyards. New, more aggressive trunk pathogens have since been identified. Research on alternatives is fragmented and limited in scope. <P>Accordingly, we address the need for effective controls for trunk diseases and communication to growers in both established growing regions that are experiencing significant losses and in nascent regions that are likely to experience such losses if left unchecked. <P>Our objectives are the following: field-evaluate double pruning against a comprehensive set of trunk pathogens, identify varieties that are both resistant to the most virulent trunk pathogens and provide marketable grape products, examine trunk pathogen communities in new production areas of the US for high-risk pathogens, and develop region-specific IPM recommendations for trunk diseases and extend to growers.
Non-Technical Summary: We will determine if preventative pruning controls trunk pathogens of grape, in field trials on East and West Coasts. In greenhouse trials, we will test varieties of winegrapes, juicegrapes, tablegrapes, and raisingrapes for resistance against the most aggressive pathogens. Together, our studies will provide a basis for the first IPM plans for grape trunk diseases. The proposed research will, therefore, reduce reliance on fungicides. <P> Approach: Cultural controls and resistant plant material are time tested, sustainable strategies for disease management, and are important components of IPM. There are no IPM plans for trunk diseases anywhere in the US, and existing IPM plans for the fruit and foliar diseases of grape do not mitigate trunk diseases. Our first two objectives are, therefore, to verify that double pruning and resistant varieties are effective against the range of trunk pathogens in all grape-growing regions of the US. These field and greenhouse studies will provide a basis for our final objective, which is to develop the first IPM plans for trunk diseases of grape. The IPM plans will be specific to all grape production systems and all growing regions of the US.