It seems like the more we learn about mycelium, the more we learn how beneficial it is to all sorts of life. Research published in the African Journal of Biotechnology (on the Mycorrhyza Literature Exchange site) shows that mycorrhyzae can help plants survive higher levels of zinc and cadmium:
...From a number of physiological indices measured in this study, microsymbionts significantly increased dry weight, root : shoot ratios, leaf number and area, plant length, leaf pigments, total carbohydrates, N and P content of infected plants as compared with non infected controls at all levels of heavy metal concentrations. Tolerance index of cowpea plants was increased in the presence of microsymbionts than in their absence in polluted soil. Microsymbionts dependencies of cowpea plants tended to be increased at higher levels of Zn and Cd in polluted soil. Metals accumulated by microsymbionts-infected cowpea plant were mostly distributed in root tissues, suggesting that an exclusion strategy for metal tolerance widely exists in them.
This news from Scientia Horticulturae (also on the Mycorrhyza Literature Exchange site) shows that mycorrhyzae can benefit tomatoes grown in saline conditions:
This study was conducted to determine if pre-inoculation of transplants with arbuscular mycorrhizal (AM) fungi alleviates salt effects on growth and yield of tomato (Lycopersicon esculentum Mill. Cv. Marriha) when irrigated with saline water. Tomato seeds were sown in polystyrene trays with 20 cm(3) cells and treated with AM fungi (AM) or without (nonAM) Glomus mosseae. Once the seedlings were reached appropriate size, they were transplanted into nonsterile soil in concrete blocks (1.6 m x 3 m x 0.75 m) under greenhouse conditions. The soil electrical conductivity (ECe) was 1.4 dS m(-1). Plants were irrigated with nonsaline water (ECw = 0.5 dS m(-1)) or saline water (ECw = 2.4 dS m(-1)) until harvest. These treatments resulted with soil EC at harvest 1.7 and 4.4 dS m(-1) for nonsaline and saline water treatments, respectively. Root colonization with AM fungi at flowering was lower under saline than nonsaline conditions. Pre-inoculated tomato plants with AM fungi irrigated with both saline and nonsaline water had greater shoot and root dry matter (DM) yield and fruit fresh yield than nonAM plants. The enhancement in fruit fresh yield due to AM fungi inoculation was 29% under nonsaline and 60% under saline water conditions. Shoot contents of P, K, Zn, Cu, and Fe were hi-her in AM compared with nonAM plants grown under nonsaline and saline water conditions. Shoot Na concentrations were lower in AM than nonAM plants grown under saline water conditions. Results indicate that pre-inoculation of tomato transplants with AM fungi improved yield and can help alleviate deleterious effects of salt stress on crop yield.
Update: As discussed elsewhere on these pages, Glomus mosseae helps plants resist the uptake of arsenic and thereby increase the uptake of phosphorus. Glomus mosseae has also been shown to reduce the uptake of copper, zinc, lead and cadmium.
A glasshouse pot experiment was conducted to investigate effects of the arbuscular mycorrhizal fungus Glomus mosseae on the growth of Vicia faba and toxicity induced by heavy metals (HMs) (Cu, Zn, Pb and Cd) in a field soil contaminated by a mixture of these metals. There was also uninoculation treatment (NM) simultaneously. Mycorrhizal (GM) plants have significantly increased growth and tolerance to toxicity induced by heavy metals compared with NM plants. P uptake was significantly increased in GM plants. Mycorrhizal symbiosis reduced the transportation of IlMs from root to shoot by immobilizing HMs in the mycorrhizal, shown by increasing the ratios of HMs from root to shoot. Oxidative stress, which can induce DNA damage, is an important mechanism of heavy metal toxicity. GM treatment decreased oxidative stress by intricating antioxidative systems such as peroxidases and non-enzymic systems including soluble protein. The DNA damage induced by heavy metals was detected using comet assay, which showed DNA damage in the plants was decreased by the GM treatment. [Journal of Environmental Sciences-China also see University of Ljubljana]Oyster mushrooms, a type of saprophytic mushroom (not mycorrhizal), have been used to detoxify soils contaminated with cadmium. However, these mushrooms would not be fit for human consumption. When using mycelium to detoxify land or help plants resist toxins, do not eat any mushrooms that fruit.