摘要
为了探讨同一菌根真菌不同菌株对重金属的耐受性 ,选用采集于内蒙古阴山山脉不同地区的粘盖牛肝菌 (Suillusbovinus)的不同菌株进行研究。首先 ,在不同浓度 Zn2 + 、Cd2 + 液体培养基中培养菌丝体 ,以了解各菌株菌丝体对重金属的耐受性及吸附能力 ,采用烘干法和原子吸收法分别测定菌丝体的生物量和菌丝体、培养液中 Zn2 +、Cd2 +含量 ,结果表明 :劈柴沟粘盖牛肝菌在 Zn2 +、Cd2 +胁迫条件下 ,生物量、吸附能力约为其余各菌株的 1.5～ 2倍。其次 ,为了探明油松 (Pinus tabulaeformis)形成菌根后对 Zn2 + 、Cd2 + 胁迫的耐受性及其耐受机理 ,采用一次性定量浇灌不同浓度 Zn2 + 、Cd2 + 溶液的方法 ,测定了菌根化油松苗地上、地下生物量及 Zn2 + 、Cd2 + 含量的分配 ,结果表明 :菌根形成后能显著促进油松的生长及对 Zn2 + 、Cd2 + 胁迫的耐受性 ,并且菌根能够帮助油松吸收基质中大量的 Zn2 +、Cd2 + ,根中重金属的含量是茎叶中的 2～ 3倍以上 ,非菌根苗在重金属浓度稍高(Zn2 + :4 0 0 mg/ kg;Cd2 + 4 0 m g/ kg)时就会死亡。经方差分析及多重比较证实 ,劈柴沟粘盖牛肝菌对 Zn2 +、Cd2 +的耐受性及对油松的促生效果与其它各菌株存在显著的差异 ,这可能是它通过把吸收的 Zn2 + 、Cd2 + 最大限度地输送到根中?
This paper investigated the heavy metal tolerance of different strains of Suillus bovinus collected in Inner Mongolia. There were two separate experiments. The first experiment involved the liquid culture of different strains of Suillus bovinus in different concentrations of Zn^(2+) and Cd^(2+). This experiment showed that the biomass accumulation and Zn^(2+) and Cd^(2+) absorption of a native strain of Suillus bovinus collected in Pi Cai Gou was 1.5~2 times higher than those of other native strains. The second experiment was carried out on the mycorrhizaed seedlings of Pinus tabulaeformis. It showed that the formation of mycorrhizae enhanced the growth and Zn^(2+) and Cd^(2+) tolerance of these seedlings. Mycorrhizae facilitated the absorption of Zn^(2+) and Cd^(2+) from the growth matrix, leading to 2~3 times higher concentration of Zn^(2+) and Cd^(2+) in roots than in shoots. In contrast, non-mycorrhizaed seedlings failed to survive in high concentrations of Zn^(2+) and Cd^(2+) (i.e., Zn^(2+) 400(mg/kg;)Cd^(2+) 40mg/kg). Statistical analysis showed that the Zn^(2+) and Cd^(2+) tolerance of the strain from Pi Cai Gou was significantly different from that of other strains. This strain also significantly enhanced the growth of the seedlings. The mechanism involved is likely to be the optimized distribution of the absorbed Zn^(2+) and Cd^(2+) between the roots and the shoots, therefore diluting the poisonous effect of Zn^(2+) and Cd^(2+).
出处
《生态学报》
CAS
CSCD
北大核心
2005年第2期220-224,共5页
Acta Ecologica Sinica
基金
国家自然科学基金资助项目 (3 0 2 60 0 86)
内蒙古自然科学基金资助项目 (2 0 0 10 90 5 -0 9)~~
关键词
粘盖牛肝菌
菌株
油松
重金属
菌根化
Suillus bovinus
strain
Pinus tabulaeformis
heavy metal
mycorrhizaed
