发酵牛粪对苏丹草根系丛枝菌根（AM）真菌侵染及磷吸收效率的影响

通过温室盆栽试验,研究接种苏格兰球囊霉(Glomus caledonium)条件下添加不同比例发酵牛粪(0.33%、0.50%和1.00%)对苏丹草(Sorghum sudanense)根系丛枝菌根(AM)真菌侵染率、土壤孢子密度、植株生物量与根冠比及根系磷(P)吸收效率的影响。结果发现,与对照相比,接种AM真菌处理植株地上部生物量趋于下降、根冠比显著提高(p<0.05),在此基础上添加0.33%或0.50%发酵牛粪处理土壤孢子密度、植株根系生物量和AM真菌侵染率均趋于升高,根冠比没有明显变化,根系P吸收效率显著提高(p<0.05);添加1.00%发酵牛粪显著提高土壤孢子密度、植株生物量和根系AM真菌侵染率(p<0.05),根冠比与仅接种AM真菌处理相同,根系P吸收效率则达到仅接种AM真菌处理的1.83倍。结果表明,添加1.00%发酵牛粪对苏格兰球囊霉扩繁及其宿主植物P吸收均具有突出促进作用。

Effects of fermented dung on root mycorhizal colonization and P-uptake efficiency of Sorghum sudanese

A pot experiment in greenhouse was carried out to compare the effects of the application level of fermented dung (0.33%, 0.50% and 1.00%) on soil spore density, root mycorrhizal colonization, plant biomass and root-shoot ratio as well as the P-uptake efficiency of Sorghum sudanense grown in a sterilized soil inoculated with arbuscular mycorrhizal fungus (AMF) Glomus caledonium. AMF inoculation tended to decrease aerial biomass of Sorghum sudanense, but significantly elevated (p<0.05) the root-shoot ratio. The application of 0.33% and 0.50% fermented dung tended to increase soil spore density, root biomass and mycorrhizal colonization of Sorghum sudanense, and significantly increased (p<0.05) the P-uptake efficiency of the root system, while did not alter shoot-root ratio. However, the application of 1.00% fermented dung significantly accelerated (p<0.05) soil spore density, root biomass and mycorrhizal colonization of Sorghum sudanense with the same shoot-root ratio and 1.83 times of the P uptake efficiency as much as that inoculated with AMF alone. It suggests that the application of 1.00% fermented dung is the proper level for the propagation of Glomus caledonium and the elevation of P-uptake efficiency of Sorghum sudanense.