Endophytic fungi of red alder (Alnus rubra) leaves and twigs in British Columbia

Abstract

A study was designed to isolate potentially pathogenic, endophytic fungi of red alder (Alnus rubra). Apparently healthy leaves and 2- to 3-year-old twigs were collected at three and eight sites, respectively, surface sterilized, cut into small pieces, and incubated on 2% malt extract agar. Ninety percent of the leaves and more than 80% of the twigs were colonized by endophytic fungi; 40 different fungi were isolated and identified. Fungi previously recorded as plant pathogens dominated the endophyte community of leaves (Gnomonia setacea, Gnomoniella tubaeformis, and Septoria alni) but were only minor components of the fungal population of twigs (Melanconis alni and a Nectria species). Abundance of each fungus species and the species composition depended on the plant organ sampled and collection site. In twigs, three main types of endophyte associations occurred among sites: the first was dominated by the unidentified "Black Mycelium 2," the second by Phomopsis sp. 2, and the third by Ophiovalsa suffusa, Pezicula livida, and Phloeosporella sp. The endophyte community of leaves was dominated by G. setacea except at one site where G. tubaeformis was the predominant fungus. Key words: endophytic fungi, fungal community, Alnus rubra, mycoherbicide.

Endophytic and epiphytic phyllosphere fungi of red-osier dogwood (Cornus stolonifera) in British Columbia

“…For example, the isolation frequency of this species was only 3% on leaves of Acer macrophylla (Sieber and Dorworth 1994), and this species was absent from leaves of Alnus rubra and Rubus spp. (Sieber et al 1991;Shamoun and Sieber 2000). The frequent occurrence of species in Epicoccum, Cladosporium, Alternaria, and Sclerotinia sclerotiorum was consistent with the result of S. controversa Mori 2004, 2005;Osono et al 2004a).…”

Intensive forest biomass harvesting and biodiversity in Canada: A summary of relevant issues

“…In southern Sweden, Nordén et al (2004) examined fungi fruiting on fine and coarse dead wood (using a 10-cm diameter limit) in a temperate broadleaf forest and determined that 75% of ascomycetes and 50% of red-list species were found on fine dead wood. Fungal endophytes that live within plant leaves and twigs are ubiquitous and diverse (Saikkonen 2007) and can be very habitat-specific; for example, leaves of birch and alder have been found to host entirely different communities of fungal endophytes than twigs of the same plants (Sieber et al 1991, Barengo et al 2000. Sherwood and Carroll (1974) documented 25 microfungi fruiting on needles and twigs from just a few Douglas-fir trees.…”

Bioactive secondary metabolites produced by microorganisms associated with plants

“…It was demonstrated that most endophytes are able to utilize, at least in vitro, most plant cell components. Most of investigated endophytes utilize xylan and pectin, show lipolytic activity and produce non-specific peroxidases and laccases (Sieber et al 1991;Leuchtmann et al 1992), chitinase ) and glucanase (Moy et al 2002). Endophyte may be a novel and good producer of xylanase (Suto et al 2002).…”