Arbuscular mycorrhizal fungi alleviate the heavy metal toxicity on sunflower ( Helianthus annuus L.) plants cultivated on a heavily contaminated field soil at a WEEE-recycling site

Abstract An 8-week pot experiment was conducted to investigate the growth and responses of sunflower ( Helianthus annuus L.) to arbuscular mycorrhizal (AM) fungal inoculations on a heavily heavy metal (HM)-contaminated (H) soil and a lightly HM-enriched (L) soil, both of which were collected from a waste electrical and electronic equipment (WEEE)-recycling site. Compared with the L soil, the H soil induced significantly larger ( P P Funneliformis mosseae ( Fm ) and F. caledonium ( Fc ) inoculation significantly increased ( P Fm -inoculated treatment. For the H soil, however, AM fungal inoculations significantly increased ( P P Fm - and Fc - inoculated treatments, respectively) and alleviated the toxicity symptoms of HMs in thylakoid structure of leaves. AM fungal inoculations in the H soil also significantly increased ( P