Abstract
Zucchini is a very valuable vegetable, easy to grow both in the field and under covering, but it is affected by pathogenic fungi. The experiment was carried out at a farm near Lublin where three zucchini cultivars, ‘Astra Polka’, ‘Atena Polka F1’ and ‘Soraya’, were cultivated in a plastic tunnel and in the field in 2008-2009. The leaves, petioles and stems of zucchini were collected for laboratory tests. Mycological analysis showed that the predominating fungi were Alternaria alternata, Fusarium spp. and Rhizoctonia solani. Fusarium spp. were isolated in the greatest numbers from zucchini plants cultivated in the field. R. solani was isolated in greater numbers from zucchini cultivated in a plastic tunnel as compared to the field.