Ecological Microclimate Influence on Grapevine Phomopsis viticola Attack Frequency in Aiud-Ciumbrud Vineyards

Phomopsis viticola (Sacc.) Sacc. (syn. Cryptosporella viticola Shear, Diaporthe viticola Nitschke, Diplodia viticola Desm, Fusicoccum viticolum Reddick, Phoma flaccida Viala & Ravaz, Phoma viticola Sacc.), is the causal agent of the grapevine disease named ‘Phomopsis cane’ and ‘Leaf spot’ in the U.S.A. or ‘Excoriose’ in Europe. This study aims to evaluate the influence of the microclimate on Phomopsis viticola attack in Aiud-Ciumbrud vineyards. The observations were done on four plots in Aiud-Ciumbrud vineyards in the period March-August 2020. Up to the end of August 2020, ten treatments with contact and systemic products based on metiram and sulphour were done together with the other standard agro-technological operations. In the ecological conditions of spring-summer 2020, with higher temperature than the average in January, February, March and June, more rain than the average in February, March and June and less rain in January, April and May, we found frequency of the excoriosis in the range of 4%-12% at the beginning of the season. After the fungicide treatments, the attack frequency decreased up to 0%-7%. In the present research work, we show that in Aiud-Ciumbrud vineyards Phomopsis viticola attack was present and influenced by the microclimate conditions and also it was reduced by the fungicide treatments.