Arbuscular mycorrhizal fungi enhance both absorption and stabilization of Cd by Alfred stonecrop (Sedum alfredii Hance) and perennial ryegrass (Lolium perenne L.) in a Cd-contaminated acidic soil

•The weekly Cd extraction by stonecrop was 4.3 times higher than that by ryegrass.•AM fungi elevated soil acid phosphatase activities and thereby available P levels.•AM fungi enhanced growth and the P and Cd absorptions of host plant in most cases.•Only Gc-inoculated stonecrop accelerated the Cd phytoextraction efficiency by 78%.•Both Gc and Gm decreased soil DTPA-extractable Cd by 21–38% via elevating soil pH. A greenhouse pot experiment was conducted to compare the phytoextraction efficiencies of Cd by hyper-accumulating Alfred stonecrop (Sedum alfredii Hance) and fast-growing perennial ryegrass (Lolium perenne L.) from a Cd-contaminated (1.6mgkg−1) acidic soil, and their responses to the inoculations of two arbuscular mycorrhizal (AM) fungal strains, Glomus caledonium 90036 (Gc) and Glomus mosseae M47V (Gm). Ryegrass and stonecrop were harvested after growing for 9 and 27 wk, respectively. Without AM fungal inoculation, the weekly Cd extraction by stonecrop (8.0μgpot−1) was 4.3 times higher than that by ryegrass (1.5μgpot−1). Both Gc and Gm significantly increased (P