镉对铅锌矿区中华山蓼根际真菌氢离子分泌的影响

为了明确镉(Cd)胁迫对云南会泽铅锌矿区中华山蓼根际真菌氢离子分泌行为的影响，探讨矿区野生植物根际真菌的生态作用。采用液体培养法，分析不同浓度(0、0.05、0.5、5 mmol/L) Cd处理条件下根际真菌培养液的pH值。结果表明：（1）铅锌矿区中华山蓼根际真菌氢离子分泌能力及其对Cd处理的响应在不同菌株间存在明显差异；（2）没有施加Cd处理，产酸能力强的真菌培养液pH值低至4.02，产酸能力弱的pH值高至8.11；（3）Cd处理对产酸能力强的真菌培养液pH值影响不明显，但导致产酸能力较弱的真菌培养液pH值显著下降，降幅最大达到3.21~3.86，培养液pH值与Cd浓度呈极显著或显著负相关。可见，Cd胁迫显著促进产酸能力较弱的铅锌矿区中华山蓼根际真菌分泌氢离子。

Effects of cadmium on the hydrogen ion secretion of rhizosphere fungi of Oxyria sinensis Hemsle in abandoned lead-zinc mining area in Huize, Yunnan, China

The aims were to elucidate the effects of cadmium (Cd) on the hydrogen ion secretion of the rhizosphere fungi of Oxyria sinensis Hemsle in abandoned lead-zinc mining area in Huize, Yunnan Province, China, and explore the ecological role of wild plants rhizosphere fungi in mining area. The pH value of liquid medium for culturing rhizosphere fungi under Cd treatment with different concentrations (0, 0.05, 0.5, 5 mmol/L) was investigated by liquid culture methods. The results showed that: (1) there were significantly difference on hydrogen ion secretion and its responses to Cd treatment of the rhizosphere fungi between the different strains. (2) Under without Cd treatment, the pH value of liquid media for culture the rhizosphere fungi with great or weak acid producing ability was low to 4.02 or high to 8.11, respectively. (3) Cd treatments had no significant effect on pH value of liquid media for culture the rhizosphere fungi with great acid producing ability, but resulted in pH value decreased significantly of liquid media for culture the rhizosphere fungi with weak acid producing ability. The largest decline was 3.21-3.86. Significant or very significant negative correlation was observed between pH value of liquid media and Cd treatment concentrations. It indicated that the secretion of hydrogen ion by the rhizosphere fungi with weak acid producing ability would be significantly promoted by Cd treatments.