Correlation of diversity of rust fungi and their host plants with disturbance and conservation of vegetation in western Panama

Abstract

The occurrence of rust fungi (Basidiomycota) infecting vascular plants on 14 sites in western Panama differing in altitude, climate, and vegetation type was analyzed. Three vegetation-types are investigated: (1) Disturbed sites where Asteraceae, Fabaceae, and Poaceae are most speciose, (2) slightly disturbed high canopy forests with sparse herbaceous undergrowth and no dominant plant family, and (3) relatively undisturbed forests with rich herbaceous undergrowth where Orchidaceae and ferns are most speciose. The majority of species of Pucciniales were found in disturbed sites on Asteraceae, Cyperaceae, Fabaceae, and Poaceae, whereas high canopy forests with sparse herbaceous layers yielded only few species of Pucciniales that were not common on any specific plant family. In undisturbed forests, a higher number of Pucciniales was found infecting mostly pteridophytes and Orchidaceae. Generally, undisturbed sites yielded a lower number of Pucciniales in relation to the number of plant species of which several species have a wide host range within the same site, and a low percentage of samples containing teliospores. Disturbed sites yielded a high number of Pucciniales in relation to the number of plant species, many rusts having a wide geographical distribution and a wide host range outside the sites, and a higher percentage of samples containing teliospores.