龙脑香科植物AM真菌的初步研究

对我国云南和海南龙脑香科植物的天然原始林和人工林AM真菌资源进行了调查,对从46处龙脑香林采回的19种龙脑香科树种的根系和根际土壤样品,分别进行显微观察和分离AM真菌的孢子,发现在所调查的19个树种中,所有树种的根系都有不同程度的AM真菌的侵染,高者可达50%,平均为21%,其中在大多数根样中发现有泡囊生成;对土壤样品的分析,分离到大量的孢子,其孢子密度从7~132个/20ml土样不等,平均为58个。对所分离到的孢子进行鉴定,发现无梗囊霉属和球囊霉属的孢子占大多数,其频度和相对多度分别为33.25和46.89;18.04和30.80。研究结果表明,龙脑香科不仅仅能够形成外生菌根,而且也能象大多数热带林木一样能够广泛的形成丛枝菌根。

PRELIMINARY SURVEY ON ARBUSCULAR MYCORRHIZAS OF DIPTEROCARPACEAE

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.