The role of arbuscular mycorrhizas in decreasing aluminium phytotoxicity in acidic soils: a review

Abstract

Soil acidity is an impediment to agricultural production on a significant portion of arable land worldwide. Low productivity of these soils is mainly due to nutrient limitation and the presence of high levels of aluminium (Al), which causes deleterious effects on plant physiology and growth. In response to acidic soil stress, plants have evolved various mechanisms to tolerate high concentrations of Al in the soil solution. These strategies for Al detoxification include mechanisms that reduce the activity of Al3+ and its toxicity, either externally through exudation of Al-chelating compounds such as organic acids into the rhizosphere or internally through the accumulation of Al-organic acid complexes sequestered within plant cells. Additionally, root colonization by symbiotic arbuscular mycorrhizal (AM) fungi increases plant resistance to acidity and phytotoxic levels of Al in the soil environment. In this review, the role of the AM symbiosis in increasing the Al resistance of plants in natural and agricultural ecosystems under phytotoxic conditions of Al is discussed. Mechanisms of Al resistance induced by AM fungi in host plants and variation in resistance among AM fungi that contribute to detoxifying Al in the rhizosphere environment are considered with respect to altering Al bioavailability.

Growth, mineral composition, fruit yield, and mycorrhizal colonization of feijoa in response to lime and phosphorus application

“…Compared with the control, the application of the lowest lime dose increased colonization intensity by 60%. Tolerance and sensitivity to acidity and to high levels of exchangeable Al in the soil vary between species and ecotypes of arbuscular mycorrhizal fungi, as well as between the stages of colonization (Seguel et al, 2013). Therefore, benefits to plant growth associated with mycorrhizal colonization can occur regardless of soil pH, varying according to the species of mycorrhizal fungi (Cavallazzi et al, 2007).…”

Effects of aluminum and moisture levels on aluminum bioaccumulation and protein content in the earthworm Octodrilus complanatus

“…Moreover, aluminum toxicity is a major problem limiting plant growth and crop production in acidic soils (Seguel et al, 2013). Indeed, Al is solubilized to the toxic cation Al +3 in acidic soils (pH≤5) (Matsumoto et al, 2000).…”

Effect of glucose, root exudates and N forms in mycorrhizal symbiosis using Rhizophagus intraradices

“…Endophytes promote the growth of plants in various ways similar to rhizosphere bacteria (Etesami et al, 2014).The beneficial roles that AM fungi play in agricultural production are well known these fungi contribute to plant health by improving plant nutrition, and in most instances, plant resistance against pathogen attacks (St.-Arnaud et al, 1995;Gianinazzi-Pearson et al, 1996). Effect of glucose, root exudates and N forms in mycorrhizal symbiosis using They also play an important role in the modulation of plant resistance to water and salt stress (Miransari et al, 2008), acidity and phytotoxic levels of Al in the soil environment (Alex Seguel et al, 2013); and in improving soil structure through the exudation of glomalin (Wu et al, 2008). Some plants colonized with AMF can be more appropriate to decontaminate As-contaminated water than soils (Caporale A.G. et al, 2014).…”