AM真菌和水分条件对稀土尾矿堆中植物生长的影响

Impacts of Arbuscular Mycorrhizal Fungi and Water Conditions on Plant Growth in Rare Earth Tailings

通过温室盆栽试验研究了不同水分处理下接种3种丛枝菌根(AM)真菌(Diversispora spurcum、Glomus aggre gatum和Glomus constrictum)后对稀土矿砂中黑麦草(Lolium perenneL.)和狗牙根(Cynodon dactylon(L.)Pers.)植物株高、地上和地下部分干重及植株内Pb和Zn含量的影响。结果表明:不同水分处理下黑麦草和狗牙根与AM真菌均有一定的结合。在干旱胁迫(W1和W2)下,接种3种AM真菌均提高了黑麦草的株高、地上和地下部分干重,其中,接种Glomus aggregatum促进作用最为显著,重度干旱胁迫(W1)处理下接种后黑麦草株高、地上和地下部分干重比对照分别提高了76.16%、202.86%和481.82%;接种Glomus constrictum显著提高了狗牙根的株高、地上和地下部分干重,W1处理下狗牙根接种后的株高、地上和地下部分干重比对照分别提高了119.17%、290.63%和247.37%。接种AM真菌的植株内Pb和Zn含量与AM真菌种类、植物品种、水分处理及重金属性质等相关,在W1处理下接种Glomus constrictum显著降低了黑麦草植株内Pb的含量,而对Zn的含量影响不大;而对于狗牙根,在W1处理下接种Glomus constrictum显著增加了其Pb和Zn的含量。此外,还测定了植物叶片丙二醛和脯氨酸含量,结果显示接种AM真菌明显降低了干旱处理下黑麦草和狗牙根叶片丙二醛和脯氨酸含量,表明接种AM真菌能有效提高植物的抗逆性。

In a greenhouse pot experiment,ryegrass（Lolium perenne L.）and bermudagrass（Cynodon dactylon（L.）Pers.）were grown in rare earth tailings under different water treatments,and the effects of inoculation with three arbuscular mycorrhizal（AM） fung（iDiversispora spurcum,Glomus aggregatum and Glomus constrictum）on plant growth,Pb and Zn contents were investigated.The results indicated that ryegrass and bermudagrass have a certain combination with different AM fungi.Under drought stress（W1 and W2）,inoculation with Glomus aggregatum markedly increased the growth of ryegrass,and for severe drought stress（W1）treatment,the plant height,shoot and root dry weight of ryegrass were increased by 76.16%,202.86% and 481.82% than those of controls,respectively.Inoculation with Glomus constrictum significantly increased the growth of bermudagrass,and for W1 treatment its plant height,shoot and root dry weight were increased by 119.17%,290.63% and 247.37% than those of controls,respectively.The contents of Pb and Zn in plant had relations with water treatment,heavy metal properties and the varieties of AM fungi and plants,etc.W1 treatment inoculated with Glomus constrictum significantly reduced Pb content in ryegrass,while the Zn content was not affected;and for bermudagrass,W1 treatment inoculated with Glomus constrictum significantly increased the contents of Pb and Zn.In addition,this work also measured the leaf MDA and proline,and the results showed that inoculation with AM fungi dramatically reduced both leaf MDA and proline contents of two plants under drought treatment,which indicated that inoculations with AM fungi could improve the stress tolerance of plants effectively.