FUNGAL ENDOPHYTES FROM THE LEAVES AND TWIGS OF QUERCUS-ILEX L FROM ENGLAND, MAJORCA AND SWITZERLAND

Leaves of Quercus ilex taken from sites in England, Majorca and Switze rland have been studied to detect the influence of the geographic posi tion of the host within and outside its native range on the compositio n of its endophytic fungal assemblages. Samples of stem tissue of and. ilex collected from the Swiss trees were also studied to confirm tiss ue-specific differences. Sixty different fungal taxa were isolated, bu t only 28 were frequent. Of the total number of isolates from the leav es from the Swiss, British and Spanish sites 87%, 31% and 63%, respect ively, were coelomycetes. Four species of Phomopsis, which includes Ph yllosticta ilicina (= Phomopsis ilicina v. d. Aa, ined.), were the mos t frequent endophytes of leaves and were either absent or rare in the twig units. Two distinct kinds of sterile mycelia were common in twigs . Swiss and Spanish trees possessed fungal assemblages distinct from t hose present in Britain. Naturalized stands were distinguished from na tive stands by the presence of rather cosmopolitan and non-specific fu ngal taxa, rare or absent in the samples collected in the native stand s. Samples derived from the native stands were colonized by more host- specific fungi. The relative frequency of two sterile mycelia in the S wiss and Spanish sites determined their separation. Phyllosticta (Phom opsis) ilicina, the most numerous leaf colonizer, was virtually absent from the bark and the xylem. The frequent occurrence of coelomycetes as endophytes of woody trees is briefly discussed.