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Summary The effect of gums formed in stone-fruit trees on the in vitro growth and development of Verticillium albo-atrum and V. dahliae cultured on Czapek Dox Agar (CzDA), Malt Extract Agar (MEA) and Potato Dextrose Agar (PDA) was investigated. Addition of gums at concentration 5 mg/cm³ to all used media greatly stimulated mycelium growth of V. albo-atrum and V. dahliae and sporulation of the pathogen. Surface of colony of the pathogens after 8 days of culturing on CzDA, MEA and PDA supplemented with gums increased twice on the first two media and three fold on PDA as compare to the control.

The aim of this work was to determine the casual agents of leaf spotting occurring on Curcuma alismatifolia Gagnep and possible methods of thir control. Symptoms of dry brown spots were observed on the leaves, stems and lower side of perianth of C. alismatifolia growing in greenhouse conditions. Pathogenicity tests with isolates obtained from diseased plants. Showed that Acremonium sp. was the main cause of disease symptoms on turmeric. The fungicides such as piraklostrobin (Signum 33 WG), fenhexamid (Teldor 500 SC), tiofanat-methyl (Topsin 500 M) and grapefruit extract (Biosept Active), greatly inhibited the growth and development of Acremonium sp. An application of piraklostrobin at the concentration of 250 μg/cm3 completely inhibited the mycelium growth. Grapefruit extract, fenhexamid and tiofanat-methyl at the concentration of 250 μg/cm3 limited the mycelium growth in 70, 75, and 80% respectively. Preventiv and curative treatments of piraklostrobin, grapefruit extract, fenhexamid and tiofanat-methyl significantly reduced the development Acremonium sp.