SURVEY OF PATHOGENIC FUNGI IN DIFFERENT REED STANDS

Although some data are available on the pathogenic fungi of the common reed (Phragmites communis Trin.), our knowledge of the biology of the se fungal species is extremely limited. These organisms may restrain t he normal development of reed plants, but can be harmful to agricultur al crops as well. Thus, a better understanding of the occurrence and e cology of these pathogens would be of significance. Our objective, the refore, was to investigate the spatio-temporal distribution of fungal diseases on reeds in relation to the environment. Investigations were carried out in different reed stands at Lake Balaton and Lake Velence, both in Hungary, in 1996-97. Disease indices were used to measure inf ection rates over time for the following fungal pathogens: Puccinia ph ragmitis. Puccinia magnusiana, Polythrinciopsis phragmitis, Deightonie lla arundinacea and Deightoniella roumeguerei. Infection data obtained from different sampling sites were compared by variance analysis. It can be stated that Puccinia phragmitis, Deightoniella arundinacea and Deightoniella roumeguerei were all dominant in good and medium quality reeds situated near the lakes. Puccinia magnusiana, however, inhabite d stands that were far from the lakes and were also of poor quality. S imilarly, Polythrinciopsis phragmitis mainly occurred in reed stands w hich were of poor quality and situated far from the water. Except for Deightoniella species, the pathogens mentioned above caused more sever e infection in areas where the reeds had not been treated in the last few years.