The resource investigation and community structure characteristics of mycorrhizal fungi associated with Chinese fir

Abstract

Chinese fir is one of the most important commercial timber species in south China. Mycorrhizal fungi has been applied in many trees and showed important effect on enhancing the productive forces and the soil activities, but there is little report about the mycorrhizal fungi on Chinese fir. So this paper investigated the mycorrhizal fungi resources of Chinese fir in Hunan province and analyzed the relation of community with the environment factors. The results showed that, abuscular mycorrhizal fungi (AMF) existed universally in the roots of Chinese fir. 75 specimen of AMF spores were isolated by wet-sieved method from this collection of the rhizosphere soils. They were identified by morphologic method to 4 genera and 9 species of AMF, which 5 species belong to Glomus, 1 of Gigaspora, 2 of Acaulospora and 1 of Scutellospora. In the isolated AMF, the importance value of Glomus mosseae, Glomus intraradices and Acaulospora laevis were more than 50% and the spore number of them was significantly higher than other species. These 3 species of AMF were considered as the dominate species in rhizosphere soil of Chinese fir in Hunan province. This research also indicated that, mycorrhiza forming was associated with the environment factors. The AMF spores density has the extremely remarkable correlational dependence with vegetation quantity in Chinese Fir forest (r²=0.943, p < 0.05). Mycorrhiza distribution also associated with seasons and forest age; the most active season of mycorrhiza was between spring and summer and the natural AMF infection rate was increased along with the increasing of forest age. The results will not only provide the theory basis for exploitation and using of mycorrhizal resource, but also enhance the survival rate of seedling and prevent the soil degradation and conserve of soil against erosion.

Key words: Mycorrhizal fungi, vesicle-abuscular, Chinese fir, mycorrhizal inocula.