龙脑香科植物对丛枝菌根真菌的影响

在天然林地和温室盆栽条件下,比较研究了龙脑香科植物对丛枝菌根(Arbuscular mycorrhizas,AM)真菌孢子密度、相对多度、频度、属的组成、丰度和侵染状况等方面的影响.结果表明,用坡垒作盆栽寄主加富培养后,菌根侵染率、泡囊、丛枝和侵入点都低于原采样植物,以原坡垒土壤中栽植苗木的侵染率为最高,可达20.3%;而以望天树根围土壤栽植的苗木为最低,仅为10.6%;坡垒还不同程度地改变了原采样植物根围土壤中AM真菌孢子的密度、相对多度、频度、属的组成、丰度等.在4种土壤中,栽植坡垒苗木后,AM真菌的孢子密度都有不同程度的增长.采用与原采样相同种类的植物作为AM真菌加富培养的寄主更有利于促进AM真菌的生长发育、保持AM的多样性.

Effects of Dipterocarpaceae on arbuscular mycorrhizal fungi

An investigation was carried out on the colonization percentage,spore density,relative abundance,occurrence frequency,and species richness of arbuscular mycorrhizal (AM) fungi on 4 species of Dipterocarpaceae trees grown both in natural forests in Yunnan and Hainan Provinces and in greenhouse pots.The results showed that all dipterocarp species were able to form AM,the colonization rates ranged from 30.6% to 45.3%,37% on average.Hopea hainanensis (Dipterocarpacea) seedlings without AM fungal colonization were cultivated in pots with soil collected from Dipterocarpacea rhizosphere,and harvested a year later.The colonization rate of the seedlings ranged from 10.6% to 20.3%,14.2% on average,indicating the significant effect of host plants on AM fungi frequency.The relative abundance of Glomu,Acaulospora and Gigaspora also varied with host plants.It was concluded that the dominant AM fungi in the rhizospheric soil of dipterocarp plants were Acaulospora spp.and Glomus spp.Using the same species of Dipterocarpacea as host plants might promote the growth and development of AM fungi,and increase the AM diversity.