五种丛枝菌根真菌对枳实生苗耐锌污染的影响

Effects of five arbuscular mycorrhizal fungi on the tolerance of trifoliate orange(Poncirus trifoliata (L.) Raf.) seedlings against zinc contamination

通过盆栽实验研究丛枝菌根(AM)真菌Glomus versiforme(G.v)、G.mosseae(G.m)、G.intraradices(G.i)、G.aggregatum(G.a)和G.etunicatum(G.e)在锌污染条件下枳实生苗的菌根侵染、生长、叶片和根系锌、磷含量及部分生理指标的影响。结果表明:锌污染基质中接种G.i、G.e和G.m显著提高了枳苗的生物量,菌根侵染率与菌根依赖性均以G.i接种处理最高,G.e处理次之,而G.v接种处理最低。AM真菌显著降低了枳地上部锌含量,促进了根部锌的积累(G.a处理除外),其中以G.i处理的地上部/根系锌转运系数最小,G.e处理次之,而G.v处理最大;AM真菌显著提高了枳根部磷含量,其中接种G.i还显著增加了枳地上部磷含量。接种G.i和G.e显著降低了枳叶片MDA含量,显著提高了枳根部CAT活性及脯氨酸含量,根部POD活性与不接种处理无显著性差异。可见,锌污染条件下接种G.i最有利于提高枳对锌污染的耐受性,G.e处理效果次之,而G.v接种处理的效果相对较弱。

A pot experiment was conducted to study the effects of inoculation with arbuscular mycorrhizal （AM） fungi Glomus versiforme （G. v ） , G. mosseae （G. m） , G. intraradices （G. i ） , G. aggregatum （G. a）, and G. etunicatum （G. e） on the mycorrhizal colonization, growth, and zinc and phosphorus contents as well as some physiological indices in leaves and roots of trifoliate orange （Poncirus trifoliata （ L. ） Raf. ） seedlings under zinc contamination. In zinc-contaminated soil, inoculation with G. i, G. e, or G. m increased the seedlings biomass significantly. The mycorrhizal colonization and mycorrhizal dependency were the highest with G. i inoculation, followed by G. e, and G. v inoculation. Inoculation with AM fungi significantly decreased the shoot zinc content, and promoted the zinc accumulation in roots （except for G. a）. The shoot/root ratio of zinc translocation coefficient was the lowest in treatment G. i, second lowest in treatment G. e, and the highest in treatment G. v. AM fungi inoculation increased the phosphorus content in roots significantly, and G. i inoculation also significantly increased the phosphorus content in shoots. Inoculation with G. i or G. e significantly decreased the MDA contents in leaves and increased the CAT activity and proline content in roots, but had little effects on the POD activity in roots, compared with the control. Our study showed that G. i inoculation was most beneficial to the tolerance of trifoliate orange against zinc contamination, followed by G. e, and G. v inoculation.