Dark septate endophyte (DSE) fungi isolated from metal polluted soils: Their taxonomic position, tolerance, and accumulation of heavy metals In Vitro |
| |
Authors: | Yujie Zhang Yan Zhang Maojun Liu Xiaodong Shi Zhiwei Zhao |
| |
Institution: | (1) Laboratory for Conservation and Utilization of Bio-Resources, and Key Laboratory for Microbial Resources of the Ministry of Education, Yunnan University, Kunming, 650091, P. R. China;(2) Department of Biology, Qujing Normal University, Qunjing, 655011, P. R. China |
| |
Abstract: | To understand the possible role of the plant root associated fungi on metal tolerance, their role in the uptake of heavy metals
and the potential transfer of these metal ions to the plant, three strains of dark septate endophytic (DSE) fungi were isolated
from a waste smelter site in southwest China, and one strain was isolated from a non-contaminated site. According to molecular
phylogenetic analysis of the ITS 1-5.8S rDNA-ITS 2 gene regions and morphological characteristics, one is identified as Exophiala pisciphila, and the other three are non-sporulating fungi under the experiment condition with the nearest phylogenetic affinities to
the Thysanorea papuana strain EU041814. Tolerance and accumulation abilities of the three DSE strains for metals were investigated in liquid culture.
Minimum inhibitory concentrations (MIC) of Pb, Zn, and Cd were determined. It was demonstrated that the tolerance of the DSE
strains varied between metal species and strains. The E. pisciphila strain is able to accumulate lead and cadmium over 20% and 5% of dry weight of biomass, respectively. Partial of the sequestrated
metals can be washed with CaCh. Morphological and enzyme activity changes taking place in the presence of excessive Pb, Cd,
and/or Zn also indicate that the mechanism of heavy metal tolerance and accumulation of the DSE strains would be a complex
process. The findings indicated promising tolerance and accumulation of the DSE strains with potential values in metal cycling
and restoration of soil and water system. |
| |
Keywords: | dark septate endophytes (DSE) Exophiala pisciphila metal tolerance accumulation |
本文献已被 SpringerLink 等数据库收录! |
|