Department of Agronomy, Federal University of Santa Maria, Campus CESNORS, Frederico Westphalen, RS, Brazil.
Braz J Microbiol. 2013 Oct 30;44(2):613-27. doi: 10.1590/S1517-83822013005000039. eCollection 2013.
Environments contaminated with heavy metals negatively impact the living organisms. Ectomycorrhizal fungi have shown important role in these impacted sites. Thus, this study aimed to evaluate the copper-resistance of ectomycorrhizal fungi isolates Pisolithus microcarpus - UFSC-Pt116; Pisolithus sp. - UFSC-PT24, Suillus sp. - UFSM RA 2.8 and Scleroderma sp. - UFSC-Sc124 to different copper doses in solid and liquid media. The copper doses tested were: 0.00, 0.25, 0.5, 0.75, 1.0 and 1.25 mmol L(-1) in the solid medium and 0.00, 0.32, 0.64 and 0.96 mmol L(-1) in the liquid medium. Copper was amended as copper sulphate in order to supplement the culture medium MNM at pH 4.8, with seven replicates to each fungus-dose combination. The fungal isolates were incubated for 30 days at 28 °C. UFSC-Pt116 showed high copper-resistance such as accessed by CL50 determinations (concentration to reduce 50% of the growth) as while as UFSC-PT24 displayed copper-resistance mechanism at 0.50 mmol L(-1) in solid medium. The UFSC-PT24 and UFSC-Sc124 isolates have increased copper-resistance in liquid medium. The higher production of extracellular pigment was detected in UFSC-Pt116 cultures. The UFSC-Pt116 and UFSC-PT24 isolates showed higher resistance for copper and produced higher mycelium biomass than the other isolates. In this way, the isolates UFSG-Pt116 and UFSC-PT24 can be important candidates to survive in copper-contaminated areas, and can show important role in plants symbiosis in these contaminated sites.
受重金属污染的环境会对生物产生负面影响。外生菌根真菌在这些受影响的地方表现出重要作用。因此，本研究旨在评估外生菌根真菌分离株 P. microcarpus-UFSC-Pt116、Pisolithus sp.-UFSC-PT24、Suillus sp.-UFSM RA 2.8 和 Scleroderma sp.-UFSC-Sc124 对不同铜剂量在固体和液体培养基中的抗性。测试的铜剂量为：固体培养基中的 0.00、0.25、0.5、0.75、1.0 和 1.25mmol L(-1)和液体培养基中的 0.00、0.32、0.64 和 0.96mmol L(-1)。铜以硫酸铜的形式添加到 pH 为 4.8 的 MNM 培养基中，每个真菌-剂量组合有 7 个重复。真菌分离物在 28°C 下培养 30 天。UFSC-Pt116 表现出高铜抗性，如 CL50 测定（降低生长 50%的浓度）所确定的那样，而 UFSC-PT24 在固体培养基中 0.50mmol L(-1)时表现出铜抗性机制。UFSC-PT24 和 UFSC-Sc124 分离物在液体培养基中具有更高的铜抗性。在 UFSC-Pt116 培养物中检测到细胞外色素的产量增加。UFSC-Pt116 和 UFSC-PT24 分离物对铜的抗性较高，产生的菌丝体生物量高于其他分离物。因此，UFSC-Pt116 和 UFSC-PT24 分离物可以成为在铜污染地区生存的重要候选物，并在这些污染地点的植物共生中发挥重要作用。
