Abstract:

Picea schrenkiana is an edificator on the northern slope of the Tianshan Mountains and plays an important role in the coniferous forests in north China. In this study, the mycorrhizal and topsoil samples were collected from the northern slope according to the altitude gradient in the Tianshan Mountains. The mycorrhizal fungi were identified by molecular biology techniques, and the contents of soil organic carbon, total N, effective P and total K were measured. Phylogenetic tree and typical correspondence analysis (CCA) were used to investigate the diversity of mycorrhizal fungi and their affecting factors. The results showed that:   ① There were 21 mycorrhizal fungi symbiotic with P. schrenkiana forest, belonging to 2 genus, 6 classes, 10 orders, 12 families and 14 genera;   GB3 ② Basidiomycota fungi were distributed in various elevation and altitude zones, while Ascomycota fungi were mainly distributed in the low-altitude zone. With the increase of altitude, the mycorrhizal infection rate (13%-36%) and the Shannon-Weiner index (1.14-2.03) were increased at first and then decreased. The Simpson's index was in a gradual decrease trend in a range of 0.49-0.63; the uniformity index varied from 0.47 to 0.63, and it was decreased at first and then increased with altitude; ③ The distribution, infection rate and diversity index of mycorrhizal fungi were mainly affected by altitude and soil organic carbon content. The total N content affected significantly only the Shannon-Werner index and the uniformity index. This study could provide a basis for the recognition and utilization of mycorrhizal fungus resources of P. schrenkiana.

Key words: mycorrhizal fungus')">

mycorrhizal fungus, infection rate, species diversity; Picea schrenkiana; Tianshan Mountains