Diversity of Putative Ectomycorrhizal Fungi in Pasoh Forest Reserve

Abstract

The tropical rainforests of Peninsular Malaysia are dominated by trees of the ectomycorrhizal family, the Dipterocarpaceae. Between 1992 and 1997 collections of putative ectomycorrhizal fungi were made in a lowland rainforest at Pasoh Forest Reserve (Pasoh FR). Collections were made during March in each year and additionally in early September 1995 and late August 1996, to coincide with the fungal fruiting seasons which occur at the end of a prolonged dry spell. During each visit of about three days duration, collections were made beside the major trails and in the Arboretum. In 1995 and 1996, collections were extended to the newly established regeneration plots, A-E where the forest had been logged in the 1950’s. A total of 296 species distributed in 19 families were recorded with many of the collections being new to science. The most frequently collected fungi were members of the family Russulaceae; a total of 114 species of Russula and 35 species of Lactarius were provisionally identified. This was followed in order of decreasing frequency by members of the Boletaceae (45 species), Amanitaceae (34 species), Cantharellaceae (13 species), Entolomataceae (13 species including possible saprophytes), Tricholomataceae (10 species), Cortinariaceae (9 species), Sclerodermataceae (8 species), Gautieriaceae (3 species), Hymenogastraceae and Secotiaceae (2 species each), and Chamonixiaceae, Clavulinaceae, Elasmomycetaceae, Gomphaceae, Hydnaceae, Hymenochaetaceae, Pisolithaceae and Thelephoraceae (1 species each). Two hundred and thirteen species, or about 72% of the collections, were single collections. Only 102 species could be placed in previously described taxa; 66% of the taxa found are apparently new to science and could only be assigned to the proximity of a known species consortium. Very few species were collected successively in two or more consecutive years, and only two species, Tylopilus maculatus and Cantharellus ianthinus were collected every year. Our collections also show that hypogeous fungi are present in the tropical rainforest. Enumeration of just one group, i.e. the putative ectomycorrhizal fungi, and data from other studies on wood decomposer fungi in Pasoh FR demonstrate that fungal biodiversity in a Malaysian lowland rainforest is very high and that more research of a long-term nature is required.