Identification and Characterization of Microsatellite Markers Useful for Genetic Analysis of Black Spruce (Picea mariana (Mill.) Populations

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.