To identify Cenococcum geophilum Fr., estimate their genetic diversity and study the effects on their genetic variation, 27 Chinese C. geophilum isolates from 6 host plant species and 5 French C. geophilum isolates we...To identify Cenococcum geophilum Fr., estimate their genetic diversity and study the effects on their genetic variation, 27 Chinese C. geophilum isolates from 6 host plant species and 5 French C. geophilum isolates were analyzed using morphological and molecular methods. The universal primers ITS1/ITS4 were used in PCR-RFLP to amplify the rDNA internal transcribed spacer （ITS） of tested C. geophilum isolates. The amplified products were digested with EcoR Ⅰ, Hinf Ⅰ, and Mbo Ⅰ, and the digested fragments of PCR products showed that there were obvious differences. A random primer （5′-CGCACCGCAC-3′） was employed in RAPD to amplify the genomic DNA of C. geophilum, and 19 detectable and reliable DNA bands of 300-2000 bp size were observed. According to the number, position, and strength of the DNA bands in agarose gel, the genetic distance and the genetic similarity among C. geophilum isolates were calculated using the PopGen Ver. 1.31 dendrogram analysis software. A phylogenetic tree was constructed based on the genetic distance by the Neighbor-Joining/UPGMA in PHYLIP. The results suggest the high level of genetic diversity among C. geophilum isolates from the same or different hosts. The effects of geographical factors or host plant species on C. geophilum genetic variation are not obvious.展开更多
Ostryopsis davidiana is a special species in China, and is also advantagous shrub of Daqing Mountains weak ecological system; Cenococcum geophilum (Fr.) spread widly in the world and have strong adaptability. C.geop...Ostryopsis davidiana is a special species in China, and is also advantagous shrub of Daqing Mountains weak ecological system; Cenococcum geophilum (Fr.) spread widly in the world and have strong adaptability. C.geophilum (Fr.) applied to experiments can be isolated from O.davidianas thin roots. It can be proved by seedling back-inoculation to O.davidiana that inoculated mycorrhizae infectious rate reaches to 67.2, and that formed mycorrhiza is the same as wild mycorrhiza. It was found that the typical sclerotium organs in seedling back-inoculation substrate. The experiments prove that C.geophilum(Fr.) has no obvious affect on O.davidianas overground parts, however, it has apparent promotion to growth of ground iameter and roots. Inoculation disposal root/shoot ratio is 2.18 times more than comparative disposal one. This may be the reason that O.davidiana can grow normally while other plants on Daqing Mountain become degraded and extinct.展开更多
基金This study was supported by National Natural Science Foundation of China （30260087）.
文摘To identify Cenococcum geophilum Fr., estimate their genetic diversity and study the effects on their genetic variation, 27 Chinese C. geophilum isolates from 6 host plant species and 5 French C. geophilum isolates were analyzed using morphological and molecular methods. The universal primers ITS1/ITS4 were used in PCR-RFLP to amplify the rDNA internal transcribed spacer （ITS） of tested C. geophilum isolates. The amplified products were digested with EcoR Ⅰ, Hinf Ⅰ, and Mbo Ⅰ, and the digested fragments of PCR products showed that there were obvious differences. A random primer （5′-CGCACCGCAC-3′） was employed in RAPD to amplify the genomic DNA of C. geophilum, and 19 detectable and reliable DNA bands of 300-2000 bp size were observed. According to the number, position, and strength of the DNA bands in agarose gel, the genetic distance and the genetic similarity among C. geophilum isolates were calculated using the PopGen Ver. 1.31 dendrogram analysis software. A phylogenetic tree was constructed based on the genetic distance by the Neighbor-Joining/UPGMA in PHYLIP. The results suggest the high level of genetic diversity among C. geophilum isolates from the same or different hosts. The effects of geographical factors or host plant species on C. geophilum genetic variation are not obvious.
文摘Ostryopsis davidiana is a special species in China, and is also advantagous shrub of Daqing Mountains weak ecological system; Cenococcum geophilum (Fr.) spread widly in the world and have strong adaptability. C.geophilum (Fr.) applied to experiments can be isolated from O.davidianas thin roots. It can be proved by seedling back-inoculation to O.davidiana that inoculated mycorrhizae infectious rate reaches to 67.2, and that formed mycorrhiza is the same as wild mycorrhiza. It was found that the typical sclerotium organs in seedling back-inoculation substrate. The experiments prove that C.geophilum(Fr.) has no obvious affect on O.davidianas overground parts, however, it has apparent promotion to growth of ground iameter and roots. Inoculation disposal root/shoot ratio is 2.18 times more than comparative disposal one. This may be the reason that O.davidiana can grow normally while other plants on Daqing Mountain become degraded and extinct.
