Isolation of endophytic fungi from leaves of eastern larch (Larix laricina) and production of biologically active metabolites by these endophytes.

摘要

Endophytic fungi have been isolated and their composition determined for many conifers but, until now, the eastern larch has not been studied. Endophytic fungi were isolated from leaves of eastern larch (Larix laricina) collected in Rockwood Park, Saint John County, New Brunswick, Canada. Two thousand three hundred and six isolates were obtained from 1600 leaves (6400 leaf segments) from 40 trees. Of the ten fungal groups isolated, RP31, RPB82, RPB65 and Coelomycete 1 represented 98.1%.;Production of biologically active metabolites by the larch endophytes was determined using interference competition bioassays. The presence of a "zone of inhibition" without physical contact served as an indication of biological activity. Isolates RP31, RPB65, XW, and L1930P produced metabolites that inhibited the fungal competitors Fusarium oxysporum, Gremmeniella laricina, Hormonema dematioides, Postia placenta and Gloeophyllum trabeum. (Abstract shortened by UMI.).