title: Nitrogen fertilizer enhances growth and nutrient uptake of Medicago sativa inoculated with Glomus tortuosum grown in Cd-contaminated acidic soil.
abstract: This study aimed to explore whether nitrogen availability could influence mycorrhizal function and their associations with host plants in Cd-contaminated acidic soils or not. A greenhouse pot experiment was conducted to assess the effects of mycorrhizal inoculation (non-mycorrhizal inoculation (NM), Glomus aggregatum (Ga), G. tortuosum (Gt) and G. versiforme (Gv)) and inorganic N amendment on the growth, nutrient and Cd uptake of Medicago sativa grown in Cd-contaminated acidic soils (10 mg Cd kg-1soil). AMF inoculations significantly increased the shoot and total biomass and decreased the shoot Cd concentration in comparison to plants uninoculated. N addition increased markedly concentration and content of N and decreased those of P in plants at all inoculation treatments. Shoot K, Na and Mg concentration in plants inoculated with Ga and Gv were decreased by N addition, whereas shoot K, Na, Ca and Mg concentration in plants inoculated with Gt were not negatively affected. It was observed that N addition only increased mycorrhizal colonization, shoot biomass, shoot K, Ca and Mg content of plants inoculated with Gt. Irrespective of N addition, plants with Gt inoculation got the maximum shoot and root P concentration and content, as well as P/Cd concentration molar ratio among all inoculation treatment. Neither AMF nor N fertilizer contributed to the decrease of soil exchangeable Cd and increase of soil pH. These results suggested that N fertilizer only elevated plant performance of alfalfa with Gt inoculation grown in acidic soil, by diluting Cd concentration and alleviating of nutrient deficiency, especially P.
authors.affiliation: College of Agro-grassland Science, Nanjing Agricultural University, Nanjing, 210095, PR China.
authors.forename: Mohan
authors.initials: M
authors.lastname: Liu
authors.affiliation: College of Agro-grassland Science, Nanjing Agricultural University, Nanjing, 210095, PR China.
authors.forename: Jian
authors.initials: J
authors.lastname: Sun
authors.affiliation: College of Agro-grassland Science, Nanjing Agricultural University, Nanjing, 210095, PR China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Li
authors.affiliation: College of Agro-grassland Science, Nanjing Agricultural University, Nanjing, 210095, PR China. Electronic address: xiaoyan@njau.edu.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Xiao
mesh_terms: D000143:Acids / Q000737:chemistry*; D001673:Biodegradation, Environmental; D018533:Biomass; D002104:Cadmium / Q000378:metabolism*; D005308:Fertilizers; D055137:Glomeromycota / Q000472:pathogenicity*; D000455:Medicago sativa / Q000254:growth & development* / Q000382:microbiology; D038821:Mycorrhizae; D009584:Nitrogen / Q000494:pharmacology*; D018517:Plant Roots / Q000737:chemistry; D012987:Soil / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000737:chemistry*
chemical_list: D000143:Acids; D005308:Fertilizers; D012987:Soil; D012989:Soil Pollutants; D002104:Cadmium; D009584:Nitrogen
keywords: AMF; Alfalfa; Cadmium; Nutrient uptake