Variation in mitochondrial DNA reveals multiple distant glacial refugia in black spruce (Picea mariana), a transcontinental North American conifer.
Range-wide genetic variation of black spruce (Picea mariana) was studied using polymerase chain reaction-random fragment length polymorphism markers of the mitochondrial genome. Four polymorphic mitochondrial DNA (mtDNA) loci were surveyed and two or three alleles were detected at each locus, resulting in 10 multilocus mtDNA types or mitotypes. A significant subdivision of population genetic diversity was detected (GST = 0.671; NST = 0.726), suggesting low levels of gene flow among populations. The distribution of mitotypes was not random (NST > GST; P < 0.05) and revealed four partially overlapping zones, presumably representative of different glacial populations. Comparison of the genetic structure derived from mtDNA markers and the colonization paths previously deduced from the fossil and pollen records allow us to infer at least three southern and one northeastern glacial populations for black spruce. The patterns revealed in this study suggest that black spruce shares its biogeographical history with other forest-associated North American species.
Chaire de recherche du Canada en génomique forestière et environnementale and Centre de recherche en biologie forestière, Pavillon C.-E. Marchand, Université Laval, Sainte-Foy, Québec, Canada G1K 7P4.
Juan P
JP
Jaramillo-Correa
Jean
J
Beaulieu
Jean
J
Bousquet
D002170:Canada; D002980:Climate; D017931:DNA Primers; D004272:DNA, Mitochondrial / Q000235:genetics; D004777:Environment; D005787:Gene Frequency; D014644:Genetic Variation; D005828:Genetics, Population; D005843:Geography; D028222:Picea / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D011157:Population Dynamics
D017931:DNA Primers; D004272:DNA, Mitochondrial