过量铜对4种外生菌根真菌的生长、碳氮和铜积累的影响

Influence of Excesive Copper on Growth and Accumulation of Carbon and Nitrogen in Mycelia of Four Kinds of Ectomycorrhizal Fungi

为了了解外生菌根真菌在过量铜胁迫下的生长和物质积累特点 ,揭示外生菌根真菌对过量铜胁迫的抵抗能力 ,研究了四种外生菌根真菌—美味牛肝菌 (Boletusedulis)、铆钉菇(Gomphidiusviscidus)、厚环乳牛肝菌 (Suillusgrevillei)和红绒盖牛肝 (Xerocomuschrysenteron)在过量铜胁迫条件下菌丝中铜积累量、菌丝生长特性以及碳氮积累速率。四种测试菌种菌丝中的铜积累量 ,随营养液中铜浓度的增加而增加 ,在 46mg L铜培养基下生长 1 5d,四种菌种菌丝内铜浓度分别是对照的 40～ 6 0倍。B .edulis和X .chrysenteron菌丝中铜浓度与培养基中铜浓度呈直线相关 ,S.grevillei和G .viscidus为指数相关。菌丝在铜胁迫下依然呈S曲线增长 ,但初始生长推迟 ,指数增长期比对照晚 1～ 2d。菌丝生物量和碳氮积累随铜浓度增加而显著降低。综合所有试验结果显示 ,四种测试菌种对过量铜的抗性强度为 :B .edulis>G .viscidus >S .grevillei>X .chrysenteron。

In order to understand the characteristic and tolerance of ectomycorrhizal fungous under the stress of excessive copper, research carried out with four kinds of ectomycorrhizal fungi strains,Boletus edulis, Gomphidius viscidus, Suillus grevillei and Xerocomus chrysenteron.Copper amount accumulated in mycelia of 4 strains had increased with the increase of concentration of copper in cultural substrate. Copper concentration in mycelia was 40～60 time higher in 46 mg/L copper treatment than in control. Dependence to relationship between copper concentration in B.edulis and X.chrysenteron mycelia and in culture substrate is linear.Concentration of copper in B.edulis and X.chrysenteron mycelia with that in culture substrate shows exponential dependence. Even though development modeling of mycelia of 4 strains shows S curve undr excessive copper stress, the initial time delayed 1 to 2 days comparing with control.But excessive copper limited the accumulation of biomass and carbon and nitrogen in mycelia.The amounts of accumulation of them are decreased with the increase of copper concentration in cultivation substrate. Combination with all result ,the strength order of 4 tested ectomycorrhizal strain on tolerance to excessive copper stress is B.edulis>G. viscidus>S.grevillei>X.chrysenteron.