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Plants commonly encounter deficient and/or toxic levels of mineral elements when grown in acidic soil, and arbuscular mycorrhizal fungi (AMF) have potential to overcome many of these effects. Switchgrass (Panicum virgatum L.) was grown in acidic Lily soil (Typic Hapludult) at pHCa 4 and 5 (soil:10 mM CaCl2, 1 :emsp14;1) and inoculated with Glomus (G.) clarum, G. diaphanum, G. etunicatum, G. intraradices, Gigaspora (Gi.) albida, Gi. margarita, Gi. rosea, and Acaulospora (A.) morrowiae to determine differences among mycorrhizal (AM) plants for mineral uptake per root length (RL). Shoots of AM plants grown in pHCa 4 and 5 soil had extensive mineral nutrient content (per plant) differences, and AM plants grown in pHCa 4 soil generally had higher and wider ranges of mineral contents than plants grown in pHCa 5 soil. Mineral uptake per RL varied extensively among AM plants. The AM plants generally enhanced uptake of phosphorus (P), nitrogen (N), sulfur (S), potassium (K), calcium (Ca), magnesium (Mg), zinc (Zn), and copper (Cu) and reduced uptake of manganese (Mn), iron (Fe), boron (B), and aluminum (Al). The G. etunicatum plants particularly had higher P, N, S, K, Mg, Zn, and Cu uptake compared to the other AM plants. Most AMF isolates used were effective in enhancing mineral uptake and reducing excess amounts of toxic elements in shoots. [ABSTRACT FROM AUTHOR]

The nutritional quality of plants is primarily controlled by concentrations of essential nutrients and potentially detrimental substances, and these are influenced to a great extent by phytotoxic aluminum (Al). Alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.), and birdsfoot trefoil (Lotus corniculatus L.), cultivars were grown in nutrient solution culture under controlled conditions and the effects of Al on growth and mineral composition of plants were evaluated. With a few exceptions, Al significantly reduced shoot and root dry weights, and generally increased the concentrations of elements in shoots. Further increases in Al tended to reduce mineral concentrations in each species and cultivar. This was probably related to root injury, reduced dry matter accumulation at higher Al, and reduced nutrient demand at higher Al levels. In alfalfa and red clover cultivars, elemental equivalency ratios for K/Mg and K/(Ca + Mg) increased, and ratios for Ca/P decreased in plants grown with Al. Forage with low Ca/P indicates poor quality, and high K/Mg and K/(Ca + Mg) ratios indicates higher grass tetany hazard to animals. Most of the elemental concentrations and nutrient ratios were similar for Al-sensitive and Al-tolerant cultivars of alfalfa and red clover. The species and cultivars used in this study had inter- and intraspecific differences in growth and nutrient concentrations, both in the presence and absence of phytotoxic levels of Al. [ABSTRACT FROM AUTHOR]