Several studies have reported high metal concentrations in soil within the vicinity of smelters in the Sudbury (Ontario) region. Continued investigation and monitoring of soil and vegetation are essential to the understanding of ecosystem recovery following the reduction of emissions from smelters and the establishment of a reforestation program. The concentrations of Cd, Co, Cu, Fe, Ni, and Zn, found in the present study were within the limits set by Ontario Ministry of Environment and Energy (OMEE) guidelines even in sites within the vicinity of the Falconbridge Smelters. The levels of these elements in black spruce (Picea mariana) tissues were much lower and far below the toxic levels for vegetation. This is the first documented report of metal content in black spruce populations in the Sudbury region.

Genetic variation and genetic structure of black spruce (Picea mariana L.) populations growing in wet land (lowlands) and dry lands (uplands) with different levels of metal contaminations were analyzed using ISSR. Polymorphic loci (P%) ranged from 65% to 90% with a mean of 75%. Nei's gene diversity (h) varied from 0.264 to 0.359 with a mean of 0.310, and Shannon's index (I) ranged from 0.381 to 0.524 with a mean of 0.449. The level of genetic variation was higher in populations from wet lands than those from dry lands. Variation within populations accounts for most of total genetic variation. The genetic distance among the black spruce (P. mariana) populations ranged from 0.171 to 0.351. The present study indicates that genetic variation and long-term exposure to metals (more than 30 years) are not associated. Cytological analysis of black spruce seeds from metal-contaminated and -uncontaminated areas showed normal mitotic behavior during prophase, metaphase, anaphase, and telophase.

Summary Large - scale isolation of microsatellite and information in any conifer species is limited. Our knowledge of microsatellite in spruce (Picea spp.) is still sketchy. Genomic libraries of P. mariana were constructed and screened with (AC)15 probes. Over 200 positive clones were found for this dinucleotide and ten were analyzed in details. They were sequenced to confirm the presence of microsatellites and to generate polymerase chain reaction (PCR) primers based on sequences flanking the microsatellites. All sequenced (AC)n clones had repeats of n > 23. Primer pairs were designed from seven sequences. These primer pairs along with 15 primer pairs from white spruce (Picea glauca) were tested on individual trees. Seven primer pairs from P. mariana and three from P. glauca (white spruce) amplified DNA from P. mariana and were used for genetic analysis of black spruce populations from uplands (drylands) and lowlands (wetlands). High levels of polymorphism and heterozygosity were observed in all the populations studied. Both highlands and lowlands showed similar levels of genetic variation. The selected microsatellites sequences are being used for genome organization analysis of black spruce.

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