Susceptibility of new grapevine germplasm to plasmopara viticola and erysiphe necator

The Directive 2009/128/EC on the sustainable use of pesticides aims at promoting the use of Integrated Pest Management and alternative approaches, such as the selection of new germplasm more tolerant or resistant to pests and diseases. In the frame of collaboration with Balkan breeders, two experimental fields were planted with 27 new cultivars obtained by crosses between Vitis vinifera (L.) and other species of the genus Vitis, and six reference cultivars commonly grown in Italy (Italia, Red Globe, Victoria, Michele Palieri, Black Magic and Crimson Seedless). In particular, nine cultivars were supplied by the Research Institute for Viticulture and Enology, Pécs (H), seven by the National Institute of Winegrowing and Winemaking, Chisinau (MO), and 11 by the Experimental Station "Sremski Karlovci" of the Institute for Pomology and Viticulture, University of Novi Sad (SE). Two years of field observations and in vitro assays were carried out to evaluate the adaptability of the new germplasm to the pedo-climatic conditions of Apulia (southern Italy). All the new cultivars showed an overall lower susceptibility to downy mildew as compared to the reference ones in the field as well as in vitro. Downy mildew infections were limited and sporification sparse and concentrated at the edges of the infected area. The most promising were the Hungarian cvs Eszter, Palatine, Bolgar Rezy, Terez, and the Serbian cvs Poleskey Muskotaly, Venus, and Piroska. An in vitro assays showed that cvs Palatine, Poleskey and Muskotaly were also more tolerant to powdery mildew as compared with the other cultivars.