Interactions between arbuscular mycorrhizal fungi and fungivorous nematodes on the growth and arsenic uptake of tobacco in arsenic-contaminated soils

• AM fungi increases the number of Aphelenchoides sp. in soils with a range of As.
• Aphelenchoides sp. promotes the development of mycorrhiza at the lowest As level.
• Co-inoculation improves the growth and As uptake of plant at the lowest As level.
• The grazing activity of fungivorous nematodes on AM fungi explains the results.

The effects of inoculation with two AM fungi (M1, Glomus caledonium; M2, Glomus spp. and Acaulospora spp.) and a fungivorous nematode Aphelenchoides sp. on growth and arsenic (As) uptake of Nicotiana tabacum L. were investigated in soils contaminated with a range of As. The reproduction of Aphelenchoides sp. was triggered by the co-inoculation of AM fungi regardless of AM fungal isolates and As levels. Stimulative effects of Aphelenchoides sp. on the development of mycorrhiza, slightly different between two AM fungi, were found particularly at the lowest As level. Irrespective of mycorrhizal inoculi, increasing soil As level decreased plant growth, but increased plant As uptake. Co-inoculation of AM fungi and Aphelenchoides sp. led plants to achieving further growth and greater As accumulation at the lowest As level. Results showed that the interactions between AM fungi and fungivorous nematodes were important in plant As tolerance and phytoextraction at low level As-polluted soil.