AM真菌Glomus versiforme对连作土壤上黄瓜生长及养分吸收的影响

为明确AM真菌Glomus versiforme在缓解连作障碍中的潜力,以黄瓜为试验材料,于黄瓜播种同时接种G.versiforme,并设立相应对照,苗龄40天时,将幼苗分别移栽至自然连作土与灭菌连作土上,研究2种土壤条件下G.versiforme对黄瓜幼苗的生长,氮磷养分吸收及根际微生物群落组成的影响。结果表明:G.versiforme对幼苗地上部与根系生长的影响因土壤条件而异。出苗第55天时,连作土上接种G.versiforme的幼苗地上部生物量是其相应对照的1.81倍,且该处理与灭菌土上菌根化处理间差异不显著。同时,灭菌土上接种G.versiforme的幼苗根系生物量是连作土上菌根化处理的1.22倍,是连作土上非菌根化处理的2.11倍。连作土上菌根化幼苗地上部生物量的显著积累与G.versiforme对幼苗叶片中氮营养的改善有关,与此同时,灭菌土上G.versiforme可促进根系对磷的吸收。此外,接种G.versiforme可在一定程度上改善土壤环境,使连作土中的细菌数量增加,真菌数量降低。土壤灭菌处理或将菌根化幼苗移栽于连作土壤上均可有效缓解设施黄瓜连作障碍。

Effects of Glomus versiforme on Growth and Nutrients Uptake of Cucumis sativus in Continuous Cropping Soil

To clarify the potential of Glomus versiforme in alleviating continuous cropping obstacles, cucumber is selected as the experimental material. The seeds were inoculated with G. versiforme, and corresponding control was designed respectively. When the seedlings were 40 days old, they were transplanted to continuous cropping soil and sterilized soil, the effects of G. versiforme on growth, nitrogen and phosphorus uptake, and microorganism population in rhizosphere of cucumber plant were investigated. The results indicated that the effects of G. versiforme on shoot and root growth varied with soil condition. On the 55th day of emergence, shoot biomass of seedlings inoculated with G. versiforme in continuous cropping soil is 1.81 times that of its corresponding control, and the difference in the shoot biomass between mycorrhizal plant in continuous cropping soil and mycorrhizal seedlings in sterilized soil was not significant. Meanwhile, root biomass of seedlings inoculated with G. versiforme grown in sterilized soil were 1.22 times and 2.11 times that of mycorrhizal seedlings and nonmycorrhizal seedlings grown in continuous cropping soil, respectively. The significant shoot biomass of seedlings in continuous cropping soil is related to nitrogen improvement in leaves, and phosphorus concentration in root was enhanced by G. versiforme in sterilized soil. Moreover, G. versiforme was beneficial to improve soil environment, namely the number of bacteria and fungi in soil was increased and reduced, respectively. Thus, sterilizing or transplanting mycorrhizal seedlings to continuous cropping soil is an effective measure to relieve the continuous obstacle in cucumber facility cultivation.