Isolates of dark septate endophytes reduce metal uptake and improve physiology of Salix caprea L

• Published in: Plant and soil 2013-09, Vol.370 (1/2), p.593-604
• Main Authors: Likar, M., Regvar, M.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Biological and medical sciences; Biomedical and Life Sciences; Chlorophyll; Cuttings; Dicotyledons; Ecology; Endophytes; Endosymbionts; Environmental aspects; Fundamental and applied biological sciences. Psychology; Fungi; General agronomy. Plant production; Health aspects; Heavy metals; Inoculation; Life Sciences; Metals; Phialophora; Physiology; Plant biology; Plant cuttings; Plant Physiology; Plant roots; Plant Sciences; Plants; Regular Article; Roots; Salix caprea; Soil and water pollution; Soil contamination; Soil fungi; Soil inoculation; Soil pollution; Soil science; Soil Science & Conservation; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Transpiration
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-013-1656-6

Background and aims Dark septate endophyte (DSE) fungi are the most frequent colonists on the roots of Salix cuprea in highly metal-contaminated soils. The present study was performed to obtain insights into the physiology and potential role(s) of DSE fungi for Salix caprea growing in metal-enriched sites. Methods Fungal isolates from S. caprea roots were identified using molecular methods, and tested for their tolerance and metal accumulation in axenic cultures. In addition, an inoculation experiment was performed to monitor the effects of the fungi on the metal uptake by the plant host. Fitness of S. caprea cuttings was assessed by photosynthetic pigment quantification and measurements of transpiration. Results Fungal isolates were identified as members of the Phialophora/Cadophora complex. They showed different levels of metal tolerance and maintained growth on metal-enriched media. In comparison to non-inoculated cuttings, the DSE-inoculated cuttings had lower leaf Cd content, and for isolates DB 146 and DB 148, also lower Zn concentrations. All DSE isolates increased the chlorophyll levels of the cuttings, with isolate DB 146 also positively affecting the transpiration rate of S. caprea. Conclusions Our findings suggest that DSE reduced the metal uptake by the S. caprea cuttings, thus suggesting a beneficial role for S. caprea in metal-enriched soils.