丛枝菌根真菌强化高粱幼苗修复锶污染土壤的研究

Arbuscular mycorrhizal fungi(AMF) enhance phytoremediation of strontium-contaminated soil by Sorghum bicolor seedlings

研究选用高粱为修复植物开展锶污染土壤治理,通过添加不同丛枝菌根真菌(arbuscular mycorrhizal fungi,AMF),包括地球囊霉、地表球囊霉、摩西球囊霉、透光球囊霉,比较不同AMF对幼苗期高粱修复锶污染土壤的调控作用。结果表明,与对照组(non-AMF)相比,AMF处理组的菌根侵染率均高于50%。与未接种AMF相比,接种AMF的高粱的生物量、株高和根长都显著增加(P<0.05),地球囊霉侵染高粱的地上和根生物量分别增加54.72%和53.26%,摩西球囊霉分别增加49.82%和37.92%。接种AMF的高粱都表现出显著的菌根依赖性(P<0.05),说明丛枝菌根真菌促进高粱生长。其中最显著的是地球囊霉和摩西球囊霉,菌根依赖性分别为154.44%和147.61%。AMF处理的高粱,其叶片和根中的锶含量与对照相比显著增加(P<0.05),转运系数都高于1。地球囊霉侵染后高粱的地上部分和根中的锶含量分别增加了86.05%和30.18%。接种地球囊霉、摩西球囊霉和地表球囊霉后,土壤中的全磷含量和速效磷含量显著降低(P<0.05)。全磷减少了15.89%～20.32%,速效磷减少了12.98%～18.49%。接种AMF显著增加了土壤磷酸酶活性(P<0.05),与对照相比,增加了21.43%～30.36%。地球囊霉、摩西球囊霉和地表球囊霉接种处理显著增加了土壤转化酶活性,增加了25.77%～28.87%。综上所述,AMF能够促进高粱幼苗对锶的富集能力和耐受性,其中,接种地球囊霉的效果最好。

In this study,we determined the effects of arbuscular mycorrhizal fungi(AMF)on the ability of Sorghum bicolor to remediate soil polluted with strontium(Sr).Seedlings of S.bicolor were inoculated with Glomus geosporum,Glomus mosseae,Glomus versiforme,or Glomus diaphanum,to compare the effects of different AMF on the strontium accumulation capacity of S.bicolor.All the AMF had infection rates of>50%,and G.versiforme showed the highest infection rate(75%).The largest biomass increases were in plants inoculated with G.geosporum and G.mosseae.The shoot biomass and root biomass of seedlings inoculated with G.geosporum increased by 54.72%and 53.26%,respectively,compared with uninoculated seedlings.Sorghum seedlings showed significant mycorrhizal dependency(P<0.05),suggesting that AMF promoted their growth.Among the AMF,G.geosporum and G.mosseae significantly increased the biomass of sorghum seedlings,and the mycorrhizal dependencies of sorghum for these two AMF were 154.44%and 147.61%,respectively.The shoot and root Sr concentrations were significantly higher(P<0.05)in AMF-inoculated sorghum than in uninoculated seedlings,and the translocation factors of AMF-inoculated sorghum were all>1.The Sr concentrations were 30.18%-86.05%higher in G.geosporum-inoculated sorghum seedlings than in uninoculated seedlings.The total phosphorus and available phosphorus contents in sorghum seedlings were significantly(P<0.05)decreased by inoculation with G.geosporum,G.mosseae,and G.versiforme;the total phosphorus content was decreased by 15.89%-20.32%,and the available phosphorus content was decreased by 12.98%-18.49%.The activity of soil phosphatase was 21.43%-30.36%higher in AMF treatments than in controls(P<0.05).The soil invertase activities were 25.77%-28.87%higher in the G.geosporum,G.mosseae,and G.versiforme treatments than in controls.In conclusion,AMF enhanced the ability of S.bicolor to accumulate and tolerate Sr,and G.geosporum was the most effective AMF.