丛枝菌根真菌和纳米磁性氧化铁对玉米生长和Fe吸收的影响

摘要

A greenhouse pot experiment was established to investigate the effects of Glomus caledonium on maize (Zea mays) plants under differential levels (01, 10, and 100 mg·kg-1) of nano-iron oxide magnetic nanoparticles (Fe3O4) artificially added soils.The results indicate that the high (100 mg·kg-1) application of nano-Fe3O4 significantly decreased (P<005) plant biomass of maize, root mycorrhizal colonization rate and plant N, P, Ca, Zn concentration, but significantly increased (P<005) shoot Fe concentration.Compared to the corresponding non-AM fungi-inoculated treatment, inoculating Glomus caledonium significantly increased (P<005) root Fe concentration and individual Fe acquisition of maize plants, but significantly decreased (P<005) shoot Fe concentration, that eventually significantly increased (P<005) plant biomass of maize with the high nano-Fe3O4 applied treatment.These results indicate that AM fungi could alleviate the toxicity of nano-Fe3O4 to plants by enhancing Fe partition in roots and reducing the translocation of Fe by maize plants.%采用温室盆栽试验方法,模拟不同纳米磁性氧化铁(Fe3O4)施加水平(01、10和100 mg·kg-1)的土壤,研究接种丛枝菌根(arbuscular mycorrhizal,AM)真菌Glomus caledonium对玉米(Zea mays)植株生长的影响.结果表明,纳米Fe3O4在100 mg·kg-1施加水平下显著降低(P<005)玉米植株地上部和地下部生物量、AM真菌侵染率和玉米植株养分(N、P、Ca、Zn)含量,显著增加(P<005)玉米植株地上部Fe含量.与未接种处理相比,在100 mg·kg-1的纳米Fe3O4施加水平下,接种AM真菌显著提高玉米植株总Fe吸收量和地下部Fe含量(P<005),但显著降低Fe的转运比率和玉米植株地上部Fe含量(P<005),改善玉米植株体内养分含量,最终显著促进玉米植株生长(P<005).该结果表明接种AM真菌可提高Fe在植物根系的分配比例,降低Fe向植株地上部的转运,从而缓解纳米Fe3O4对宿主植物的毒害作用.