PRELIMINARY SURVEY ON ARBUSCULAR MYCORRHIZAS OF DIPTEROCARPACEAE
龙脑香科植物AM真菌的初步研究

A preliminary investigation on arbuscular mycorrhizal(AM) status of 19 dipterocarp species grown in both plantation and natural forest was carried out in 46 different sites in Yunnan and Hainan Province, China. The colonization percentage, AM fungal (AMF) spore density, and relative abundance and occurrence frequency were determined. Results showed that all dipterocarp species were able to form AM, the colonization rates ranged from 1 to 50%, with an average 21%, their vesicle number from 0 to 2.8/mm root length, and the spores density from 7 to 132 spores/20ml soil, with an average 58/20ml. Most of the spores were belong to Acaulospora and Glomus. The occurrence frequency and relative abundance of the two genera were 55.17% and 72.72%, 35.40% and 50.72%, respectively. It was suggested that the dominant AMF in the rhizosphere soil of dipterocarp plants were Acaulospora spp. and Glomus spp.