摘要
本研究采用盆栽试验法,研究了不同浓度Cd胁迫下,接种外生菌根菌——褐环乳牛肝菌(Suillus luteus)对樟子松(Pinus sylvestris var.mongolica)苗期植株的生长及叶绿素含量、抗氧化酶(CAT、POD和SOD)活性、细胞渗透调节物质(可溶性糖、MDA和游离脯氨酸)含量和根际土壤酶(过氧化氢酶、脲酶和碱性磷酸酶)活性的变化。结果表明:1年生樟子松苗木在Cd胁迫1个月后,接菌处理组无论在苗木生长、抗氧化酶活性方面均高于对照组,且大部分指标达到显著差异水平(P<0.05)。各接菌处理组菌根侵染率达48.0%以上。抗氧化酶活性方面,CAT和POD活性呈现出随着胁迫程度的加深,先下降后上升的变化趋势,SOD活性则呈现出地上与地下部分"上下对称"的变化趋势。同时,通过对各处理组苗木细胞渗透调节物质的定量测定,接菌处理组的细胞受破坏程度显著低于不接菌处理组。对苗木根际土壤酶分析结果表明,Cd胁迫下,施加外生菌根菌可以有效提高樟子松根际土壤酶的活性(尤其是脲酶),进而起到增加樟子松根际土壤生物活性作用。综上,接种外生菌根真菌对樟子松缓解重金属Cd胁迫具有明显的促进作用。Cd胁迫下,外生菌根可以有效正向调节樟子松的生长、抗氧化胁迫能力并提高苗木细胞渗透调节作用,进而提高苗木对重金属的耐受性和提高苗木根际土壤生物活性。本研究可以为重金属污染土地的有效治理和利用木本植物修复改良重金属污染土壤提供参考。
A pot experiment was conducted to study the effects of different cadmium（Cd） concentrations on growth and physiological traits,chlorophyll contents,activities of antioxidant enzyme（CAT,POD and SOD）,contents of osmotic adjustment substances（soluble sugar,MDA and free proline）,and activity of rhizosphere soil enzymes of Pinus sylvestris var.mongolica by inoculating ectomycorrhizal fungus Suillus luteus.The results showed that after 1 month Cd stress treatment on 1-year-old P.sylvestris var.mongolica seedlings,the seedling growth and the antioxidant enzyme activities in inoculated group were higher than those in un-inoculated group,and most of the indicators investigated reached significant difference levels（P〈0.05）.CAT and POD activities declined and then increased with the increase of Cd concentration,while SOD activity showed a symmetrical pattern between the aboveground and underground parts.Meanwhile,the determination of seedling cell osmotic regulation substances showed that the cell damage degree of inoculated group was lower than that of un-inoculated group.The results indicated that inoculating ectomycorrhizal fungi could help relieve the stress of Cd of P.sylvestris var.mongolica seedlings.Under Cd stress,ectomycorrhizal fungi can effectively improve rhizosphere soil enzyme activity of P.sylvestris var.mongolica seedlings（especially the urease）,and further improve the tolerance of P.sylvestris var.mongolica seedlings to heavy metal.The results can provide reference for phytoremediation of heavy metal polluted soils using woody plants.
出处
《生态学杂志》
CAS
CSCD
北大核心
2017年第11期3072-3078,共7页
Chinese Journal of Ecology
基金
沈阳农业大学引进人才启动项目(2015年)
黑龙江林科院人才培养基金项目(2015R01)
国家自然科学基金项目(31670649
31200484
31700564)
黑龙江省级基本科研业务费项目(黑龙江省财政厅项目)资助
关键词
外生菌根菌
樟子松
生理指标
土壤酶
ectomycorrhizal fungi
Pinus sylvestris var. mongolica
physiological index
soil enzyme
