Endangerment of Ostrya rehderiana Chun and its relationship with rhizosphere soil microflora

Ostrya rehderiana Chun (Or) is an endangered plant in China. The rhizosphere microbial community is one of the key factors influencing the growth and development of plants. Soil samples in the rhizosphere of wild Or (W_Or), cultivated Or (C_Or) and the predominant plant species Cryptomeria fortunei Hooibrenk ex Otto et Diet (CfH) all growing in the same habitat were investigated. We performed polymerase chain reaction (PCR) in 16S rDNA region for bacteria and internal transcribed spacer (ITS) rDNA regions for fungi in the rhizosphere. At genus level the predominant bacteria in the rhizosphere of both W_Or and CfH were higher, and the species distribution profiles exhibited higher similarities. The distribution profiles of fungal species at the genus level in the rhizosphere of W_Or and C_Or also exhibited higher similarities. The similarity in bacterial diversity at the genus levels between W_Or and C_Or exhibited higher similarities, whereas that of fungal diversity at the genus levels between W_Or and CfH exhibited higher similarities. There existed Rhizophlyctis and Termitomyces species capable of degrading cellulose and lignin in the rhizosphere of both W_Or and C_Or. These species may affect the normal formation of the cell wall of Or. Bacterial species Mycena were capable of enhancing the growth of plant root system, Suillus, Geomyces, Gigaspora and Phlebia were capable of degrading many types of wastes were only present in CfH. The absence of these beneficial strains in both W_Or and C_Or may be one of the causes of the growth and development retardation of Or.