胡桃楸林地胡桃醌与土壤微生物种群关系

Relationship between exogenous juglone and soil microbial population in a Manchurian walnut plantation

以胡桃楸纯林为研究对象,在室内分别对林地土样进行了添加胡桃醌与灭菌的控制实验,研究了胡桃醌与土壤微生物之间的相互影响。结果表明,灭菌后胡桃醌的分解速率明显降低。培养5 d后,对照中胡桃醌含量已所剩无几,仅为原来的6.07%,而灭菌土壤中胡桃醌的含量仍为原来的42.92%。添加胡桃醌后,磷脂脂肪酸总量显著偏低,革兰氏阳性菌、革兰氏阴性菌、真菌、放线菌的生长均受到抑制。该研究证明,微生物对胡桃醌的分解具有促进作用,胡桃醌对土壤微生物的生长具有抑制作用。

A laboratory experiment with the soil samples collected from a pure Manchurian walnut plantation was conducted under juglone addition and soil sterilization to study the interactions be tween added jug]one and soil microbes. After soil sterilization, the decomposition rate of added juglone decreased obviously. On the 5th day of incubation, only a few of the added juglone （6.07% of the total） was found in unsterilized soil, and the remained juglone in sterilized soil occupied 42.92% of the total. After juglone addition, the total quantity of soil PLFAs decreased significantly, and the growth of soil grampositive bacteria, gramnegative bacteria, fungi, and aetinomycetes was all inhibited. This study demonstrated that soil microbes facilitated juglone de composition, while juglone had inhibitory effects on the growth of soil microbes.