The arbuscular mycorrhizal fungus Glomus mosseae gives contradictory effects on phosphorus and arsenic acquisition by Medicago sativa Linn

The arbuscular mycorrhizal fungus Glomus mosseae can enhance arsenic tolerance in Medicago truncatula by increasing plant phosphorus status and restricting arsenate uptake

“…1). Our results are in agreement with other studies which have also reported higher tolerance of AMF to As as indicated by enhanced growth of mycorrhizal plants compared with non-mycorrhizal plants (Gonzalez-Chavez et al, 2002;Ahmed et al, 2006;Leung et al, 2006;Trotta et al, 2006;Chen et al, 2007). Adding arsenate to the soil increased the As concentrations in shoots and roots of both mycorrhizal and nonmycorhizal plants and the trend was less pronounced in plants inoculated with G. mosseae (Fig.…”

“…Consequently, AM colonization increased the shoot and root P:As content ratio, especially at higher soil As levels (Table 2). It can be inferred that the AM fungus can enhance host plant P nutrition while suppressing plant As uptake, and this agrees with a recent study by Chen et al (2007). Plants take up arsenate via the phosphate uptake system (Asher and Reay, 1979;Meharg andMacnair, 1990, 1992) and the suppression of high affinity P uptake therefore assists plants to enhance arsenate tolerance (Meharg and Macnair, 1992).…”

Arbuscular mycorrhiza enhanced arsenic resistance of both white clover (Trifolium repens Linn.) and ryegrass (Lolium perenne L.) plants in an arsenic-contaminated soil

“…Obviously, this involved improved plant P nutrition, which resulted in better plant growth and enhanced plant tolerance to As contamination. In accordance to our previous findings (Chen et al, 2007a), the alleviated As phytotoxicity was most likely achieved by a ''growth dilution effect'', i.e., although the relatively large AM plants had higher As content per plant than the non-inoculated plants, their As concentrations in shoots were lower (Fig. 5).…”

Chromium immobilization by extraradical mycelium of arbuscular mycorrhiza contributes to plant chromium tolerance

“…Additionally, AMF can relieve plant drought stress (Li et al, 2014), protect host plants from pathogens (Singh et al, 2013b), improve soil structure (Rillig and Steinberg, 2002), and even play an important role in maintaining plant biodiversity and ecosystem stability (van der Heijden et al, 1998). Various studies have demonstrated that AM symbiosis take an active part in plant resistance to heavy metal contamination including As, Cd, Cu and Cr etc (Chen et al, 2007a(Chen et al, ,b, 2005Davies et al, 2001;Wu et al, 2014). For example, Davies et al (2001) found that AMF could enhance Cr tolerance of sunflower (Helianthus annuus) under Cr stress.…”

“…One possible mechanism is that AM symbiosis can improve plant growth through enhancing plant P uptake, which subsequently result in so-called "growth dilution effects" on metals in plants (Chen et al, 2007a). AMF is well known for its positive effects on plant P nutrition especially under stressful conditions.…”