SUSCEPTIBILITY TO DOWNY MILDEW (PLASMOPARA VITICOLA) AND POWDERY MILDEW (ERYSIPHE NECATOR) OF DIFFERENT VITIS CULTIVARS AND GENOTYPES

Turkey has a very old history of viticulture and also homeland of the grapevine (Vitis spp.). Vitis cultivars belonging to different species are grown in almost every region in the country. However, particularly downy mildew and powdery mildew diseases affect the cultivars belonging to Vitis vinifera. In northern of Turkey Vitis labrusca and hybrids between V. vinifera and V. labrusca are rather common. V. labrusca cultivars or genotypes exhibit generally higher degree of resistance than V. vinifera cultivars. However, resistance level can vary from cultivar to cultivar and even from clone to clone within one cultivar. In this study, different Vitis hybrids and genotypes which exhibit different downy and powdery mildew susceptibility are compared for two years. Especially some V. labrusca hybrids and genotypes appeared resistance for both diseases. On the other hand, interspecific crosses and V. vinifera cultivars were found to be more susceptible. Using resistant lines as parent in later breeding activities, it could be possible grow high quality table cultivars with much fewer pesticide applications or possibly without them.