钼污染对丛枝菌根和球囊霉素的影响

Effects of molybdenum pollution on arbuscular mycorrhizal fungi and GRSP

丛枝菌根作为地球上最广泛的共生体,在各种逆境环境中发挥着重要作用。基于不同钼污染程度的钼矿区,分析了钼污染对丛枝菌根真菌侵染、繁殖及其分泌球囊霉素能力的影响。结果表明,在4个不同钼污染级别的土壤中,丛枝菌根真菌与植物共生关系的形成未受到钼污染的影响,平均菌根侵染频度为50.64%。洛阳钼矿区土壤的平均孢子密度为19.20个·g^(-1)风干土,其中草本植物和木本植物根际土壤的平均孢子密度分别为18.2和20.3个·g^(-1)风干土。在重度钼污染级别下,土壤总球囊霉素和易提取球囊霉素含量分别为1.53和0.72 mg·g^(-1),显著低于无钼污染土壤中总提取球囊霉素和易提取球囊霉素含量。相关性分析结果表明,钼含量与孢子密度和球囊霉素间存在显著负相关关系,而与菌根侵染率没有显著相关性。同时,除在轻度钼污染级别下,球囊霉素在其他3个钼污染级别下均与菌根侵染率不存在显著相关性。可见,钼污染虽然不影响丛枝菌根真菌对植物的侵染,但对丛枝菌根真菌繁殖及分泌球囊霉素的能力有一定的抑制作用。

Arbuscular mycorrhizal fungi,as the most widespread symbionts in earth,play an important role in all kinds of adversity environment.This study analyzed the effects of molybdenum pollution on the infection,reproduction and the ability of glomalin secretion by arbuscular mycorrhizal fungi in the molybdenum mining areas with different levels of molybdenum pollution.The results showed that,the formation of the symbiotic relationship between arbuscular mycorrhizal fungi and plants was not affected by molybdenum pollution under 4 different levels.The average mycorrhizal infection frequency was 50.64%.The average spore density of soil in Luoyang molybdenum mining area was 19.20 spores·g^(-1)airdried soil,among which the average spore density of herb and woody plant rhizosphere soil was 18.2 and 20.3 spores·g^(-1)airdried soil,respectively.Under severe level of molybdenum pollution,the content of total and easily extractable glomalin in soil were significantly lower than those of nonmolybdenum contaminated soil,with the value of 1.53 and 0.72mg·g^(-1),respectively.There was a significantly negative correlation between molybdenum content and spore density or glomalin,but there was no significant correlation with mycorrhizal infection rate according to the results of correlation analysis.At the same time,there was no significant correlation between the glomalin and the mycorrhizal infection rate under the other three molybdenum pollution levels except for the light molybdenum pollution level.It can be seen that although molybdenum pollution does not affect the infection of arbuscular mycorrhizal fungi on plants,it has a certain inhibitory effect on the ability of arbuscular mycorrhizal fungi to multiply and secrete glomalin.