Evidence from Sequence-Tagged-Site Markers of a Recent Progenitor-Derivative Species Pair in Conifers
Black spruce (Picea mariana [B.S.P.] Mill.) and red spruce (Picea rubens Sarg.) are two conifer species known to hybridize naturally in northeastern North America. We hypothesized that there is a progenitor-derivative relationship between these two taxa and conducted a genetic investigation by using...
Saved in:
Published in | Proceedings of the National Academy of Sciences - PNAS Vol. 97; no. 21; pp. 11331 - 11336 |
---|---|
Main Authors | , , , |
Format | Journal Article |
Language | English |
Published |
United States
National Academy of Sciences of the United States of America
10.10.2000
National Acad Sciences National Academy of Sciences The National Academy of Sciences |
Subjects | |
Online Access | Get full text |
Cover
Loading…
Summary: | Black spruce (Picea mariana [B.S.P.] Mill.) and red spruce (Picea rubens Sarg.) are two conifer species known to hybridize naturally in northeastern North America. We hypothesized that there is a progenitor-derivative relationship between these two taxa and conducted a genetic investigation by using sequence-tagged-site markers of expressed genes. Based on the 26 sequence-tagged-site loci assayed in this study, the unbiased genetic identity between the two taxa was quite high with a value of 0.920. The mean number of polymorphic loci, the mean number of alleles per polymorphic locus, and the average observed heterozygosity were lower in red spruce (P = 35%, AP= 2.1, Ho= 0.069) than in black spruce (P = 54%, AP= 2.9, Ho= 0.103). No unique alleles were found in red spruce, and the observed patterns of allele distribution indicated that the genetic diversity of red spruce was essentially a subset of that found in black spruce. When considered in combination with ecological evidence and simulation results, these observations clearly support the existence of a progenitor-derivative relationship and suggest that the reduced level of genetic diversity in red spruce may result from allopatric speciation through glaciation-induced isolation of a preexisting black spruce population during the Pleistocene era. Our observations signal a need for a through reexamination of several conifer species complexes in which natural hybridization is known to occur. |
---|---|
Bibliography: | ObjectType-Article-2 SourceType-Scholarly Journals-1 ObjectType-Feature-1 content type line 23 ObjectType-Article-1 ObjectType-Feature-2 To whom reprint requests should be addressed at: Forest Biology Research Centre, Université Laval, Sainte-Foy, QC, Canada G1K 7P4. E-mail: bousquet@rsvs.ulaval.ca. Edited by Ronald R. Sederoff, North Carolina State University, Raleigh, NC, and approved July 27, 2000 Present address: Canadian Grain Commission, Grain Research Laboratory, 1400–303 Main Street, Winnipeg, MB, Canada R3C 3G8. |
ISSN: | 0027-8424 1091-6490 |
DOI: | 10.1073/pnas.200417097 |