关键词: 外生菌根真菌, 铝胁迫, 抗氧化酶, 营养元素

Abstract: Effects of treatment on biomass, pH, nutrient uptake, antioxidant enzyme activity, and MDA content of Suillus luteus (Sl), Suillus bovines (Sb) and Suillus placidus (Sp) were tested by liquid culture with different concentrations of Al³⁺ (0, 0.2, 0.4, 0.8, 1.2 and 1.6 mmol·L^–1). The results showed that aluminum treatment significantly increased the biomass, P content, and Al content of the three strains, and decreased the pH in the culture medium. When the concentration of Al³⁺was 0.8 mmol·L^–1, the biomass increase in the strain was the largest, and the aluminum content of the three strains treated with Al³⁺at various concentrations was Sp>Sb>Sl; The potassium content showed a trend of first increasing and then decreasing as the concentration of Al³⁺ increased. Low concentration of Al³⁺ (≤0.4 mmol·L^–1) significantly promoted the accumulation of nitrogen in the Sl strain, and the treatment with 0.4 mmol·L^–1 Al³⁺ increased by 42.65% compared to the treatment without aluminum. Aluminum treatment also significantly decreased the POD and SOD activities of the strain, and increased the MDA content of the strain. The biomass of the strain was significantly positively correlated with the N, P, and K content of the mycelium (P<0.01), with the highest correlation with P content (r=0.635). To sum up, the concentration of Al³⁺ in the environment is a key factor affecting the absorption of aluminum by ectomycorrhizal fungi. At a certain concentration of Al³⁺, ectomycorrhizal fungi can increase the absorption of nutrient elements N, P, and K, improve the activity of mycelial enzymes, reduce the content of MDA, alleviate aluminum toxicity, and enhance their viability under aluminum stress, providing a theoretical basis for screening excellent strains with strong resistance (or tolerance) to aluminum.

Key words: ectomycorrhizal fungi, aluminum stress, antioxidant enzymes, nutrient element