title: Nickel and Copper Toxicity and Plant Response Mechanisms in White Birch (Betula papyrifera).
abstract: Nickel (Ni) and copper (Cu) are the most prevalent metals found in the soils in the Greater Sudbury Region (Canada) because of smelting emissions. The main objectives of the present study were to (1) determine the toxicity of nickel (Ni) and copper (Cu) at different doses in Betula papyrifera (white birch), (2) Characterize nickel resistance mechanism, and (3) assess segregating patterns for Ni and Cu resistance in B. papyrifera populations. This study revealed that B. papyrifera is resistant to Ni and Cu concentrations equivalent to the levels reported in metal-contaminated stands in the GSR. Resistant genotypes (RG) accumulate Ni in roots but not in leaves. Moderately susceptible (MSG) and susceptible genotypes (SG) show a high level of Ni translocation to leaves. Gene expression analysis showed differential regulation of genes in RG compared to MSG and SG. Analysis of segregation patterns suggests that resistance to Ni and Cu is controlled by single recessive genes.
authors.affiliation: Biomolecular Sciences Program, Laurentian University, Sudbury, ON, P3E 2C6, Canada.
authors.forename: Gabriel
authors.initials: G
authors.lastname: Theriault
authors.affiliation: Biomolecular Sciences Program, Laurentian University, Sudbury, ON, P3E 2C6, Canada. knkongolo@laurentian.ca.|Department of Biology, Laurentian University, Sudbury, ON, P3E 2C6, Canada. knkongolo@laurentian.ca.
authors.forename: Kabwe
authors.initials: K
authors.lastname: Nkongolo
mesh_terms: D029662:Betula / Q000187:drug effects / Q000502:physiology*; D002170:Canada; D003300:Copper / Q000032:analysis / Q000633:toxicity*; D009532:Nickel / Q000032:analysis / Q000633:toxicity*; D018515:Plant Leaves / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism; D012987:Soil; D012989:Soil Pollutants / Q000032:analysis / Q000633:toxicity*; D018675:Toxicity Tests
chemical_list: D012987:Soil; D012989:Soil Pollutants; D003300:Copper; D009532:Nickel
keywords: Betula papyrifera (white birch); Gene expression; Genetic tolerance; Metal contamination; Metal translocation; Nickel and copper toxicity