Jacek Nawrocki

Fungi isolated from diseased early green fruits and fruits of blueberry (Vaccinium corymbosum L.)Grzyby izolowane z chorych zawiązków owocowych i owoców borówki wysokiej (Vaccinium corymbosum L.)

The aim of carried out research was an isolation and identification of fungi from diseased blueberry (Vaccinium corymbosum L.) fruits collected at three dates: during fruit set, maturing of fruit and fruitharvest. In general 14 species and forms of fungi were identified out of 319 isolates. It was quite a significant difference in the communities of microorganisms isolated from fruits in reference to different stages of plant development. Common infection of fruit buds by Botrytis cinerea and Alternaria alternata suggests capability of primary infection during flowering period. Fungi species, which produce toxins, especially genus: Alternaria, Cladosporium, Fusarium and Penicillium present high threat to plants. B. cinerea, Alternaria spp., Colletotrichum gleosporioides and Monilia fructigena have been recognized as particularly dangerous to blueberry crops due to frequency of their occurrence and harmfulness at different stages of fruit development, and long-term character of blueberry production.

Fruit susceptibility of several cultivars of blueberry (Vaccinium corymbosum L.) to diseases Podatność owoców kilkunastu odmian borówki wysokiej (Vaccinium corymbosum L.) na choroby

Summary The observations were conducted on 11 cultivars of blueberry at different time of fruit maturing (early ripening, about average time of maturing and late ripening) and at three dates: during fruit set, maturing of fruit and harvest time. Quite significant differences in the susceptibility of each cultivar in each group to fruit diseases, which also depended on the phase of their development, were revealed. Based on three evaluations of health status of blueberry plants it has been concluded that the most sensitive to diseases are cultivars: Blueray, Crotan, and Bluejay, and the most resistant: Boniface, Puru and Brigitta.