SPECIES-SPECIFIC RAPD FINGERPRINTS FOR THE CLOSELY-RELATED PICEA-MARIANA AND P-RUBENS

Species-specific molecular markers were designed to assist in the iden tification of closely related black spruce (Picea mariana [B.S.P.] Mil l) and red spruce (P. rubens Sarg.) in northeastern North America. Tre es from six provenances of black spruce and three provenances of red s pruce were sampled from outside the sympatric zone. They were first cl assified using a composite index of five qualitative morphological tra its. The species-specific genetic markers were developed using random amplified polymorphic DNAs (RAPD) and a combination of bulk sample and individual tree analyses. Each species bulk sample was constructed fr om DNAs obtained from 12 trees that were from outside the sympatric zo ne and showed a morphological composite index specific of each species . A total of 161 primers were screened with the bulk samples. From the se, 52 primers showing segregating fingerprints were further screened with the individual trees. Most of the markers observed were shared by the two species, and there was less diversity in P. rubens. A small n umber of markers were found to be monomorphic or nearly monomorphic an d specific to either P. mariana or P. rubens. These markers remained s pecies-specific when F-1 progenies derived from independent intraspeci fic crosses were screened, and they were subsequently found to co-segr egate in hybrids derived from independent interspecific crosses here u sed as controls.