SEQUENCE-TAGGED-SITE (STS) MARKERS OF ARBITRARY GENES - DEVELOPMENT, CHARACTERIZATION AND ANALYSIS OF LINKAGE IN BLACK SPRUCE

Sequence-tagged-site (STS) markers of arbitrary genes were investigate d in black spruce [Picea mariana (Mill.) B.S.P.]. Thirty-nine pairs of PCR primers were used to screen diverse panels of haploid and diploid DNAs for variation that could be detected by standard agarose gel ele ctrophoresis without further manipulation of amplification products. C odominant length polymorphisms were revealed at 15 loci. Three of thes e loci also had null amplification alleles as did 3 other loci that ha d no apparent product length variation. Dominant length polymorphisms were observed at 2 other loci. Alleles of codominant markers differed in size by as little as 1 bp to as much as an estimated 175 bp with ne arly all insertions/deletions found in noncoding regions. Polymorphism s at 3 loci involved large (33 bp to at least 114 bp) direct repeats a nd similar repeats were found in 7 of 51 cDNAs sequenced. Allelic segr egation was in accordance with Mendelian inheritance and linkage was d etected for 5 of 63 pairwise combinations of loci tested. Codominant S TS markers of 12 loci revealed an average heterozygosity of 0.26 and a n average of 2.8 alleles in a range-wide sample of 22 trees.