Foliar diseases of willows (<Emphasis Type="Italic">Salix</Emphasis> spp.) in selected locations of the Karkonosze Mts. (the Giant Mts)

The species of Salix herbacea L. and Salix lapponum L. are the rare relicts within the genus of Salix. With respect to their phylogeography, they are classified into the taxa of the Arctic-Alpine distribution. They can be found in the Arctic zone (Greenland, Scandinavia, Spitsbergen) as well as in such geographically separated areas as the mountains of lower latitudes like the Alps, the Sudetes or the Carpathians. Another species of willow occurring in the mountains of Europe, and more specifically on montane positions of the Balkan-Carpathian distribution is S. silesiaca. The aim of the study was to determine the severity of the diseases of the willows growing in selected locations in the Karkonosze Mountains. The research was conducted in the years 2014 and 2015 in the Kocio? ?omniczki the ?omniczka Cirque] and the Wielki and Ma?y ?nie?ny Kocio?, the Great and Small Snowy Cirques] at intervals of 4 weeks, from April to October. Field observations included the species of the genera Salix: S. herbacea, S. silesiaca and S. lapponum. Disease symptoms were identified with the percentage of infected plants at selected locations, as well as the percentage of infected leaves, recorded. In the course of the research, symptoms of rust caused by Melampsora epitea and M. alpina (S. herbacea and S. silesiaca), black spot blight caused by Rhytisma salicinum (S. silesiaca) and leaf spot, probably caused by a complex of fungal taxa (S. herbacea), were detected on the leaves of Salix spp. growing in post glacial cirques. During the study period, there were no disease symptoms on S. lapponum. A total of 13 species of fungi were isolated from the infected leaves of S. herbacea. In the first year, the highest share in the fungal assembly was taken by Penicillium notatum, followed by Alternaria alternata and an unidentified species of the genus Ceuthospora. In the second year of the research, Ceuthospora spp. and A. alternata predominated in the species assembly of fungi in the infected leaves of the herb willow.