Skip to Main Content
Reproductive barriers and hybridity in two spruces, Picea rubens and Picea mariana, sympatric in eastern North AmericaAuthor(s): John E. Major; Alex Mosseler; Kurt H. Johnsen; Om P. Rajora; Debby C. Barsi; K.-H. Kim; J.-M. Park; Moira Campbell
Source: Can. J. Bot. 83: 163–175
Publication Series: Miscellaneous Publication
PDF: View PDF (576 KB)
DescriptionHybridization between red spruce (Picea rubens Sarg.) and black spruce (Picea mariana (Mill.) BSP), lateand early-successional species, respectively, has resulted in identification and management problems. We investigated the nature and magnitude of reproductive and life-cycle success barriers in controlled intra- and inter-specific crosses of red and black spruce. We quantified a number of reproductive, germination, phenological, and performance traits, and examined traits by parental pedigree and hybrid index. Species' pollen had no effect on number of aborted or nonpollinated ovules. Controlled intraspecific crosses had, on average, 6.6 times more filled seeds than interspecific crosses. Cone and seed morphometric traits were species specific, with seed traits showing negative hybridization effects on both species. Germination, cotyledon number, and seedling height had significant species-specific traits, with hybrids showing an additive or slightly negative heterosis. Severe, negative heterosis appears to be of limited importance as an isolating barrier between red and black spruce. Reproductive phenology was remarkably similar among species and hybrid progenies when grown in common garden experiments. Crossability barriers are clearly paramount in maintaining the separation of the species. Ecological separation based on ecophysiological differences (e.g., shade tolerance) also represents an important prezygotic barrier for minimizing the negative effects of hybridization (e.g., postzygotic inviability) on reproductive fitness.
- You may send email to firstname.lastname@example.org to request a hard copy of this publication.
- (Please specify exactly which publication you are requesting and your mailing address.)
- We recommend that you also print this page and attach it to the printout of the article, to retain the full citation information.
- This article was written and prepared by U.S. Government employees on official time, and is therefore in the public domain.
CitationMajor, John E.; Mosseler, Alex; Johnsen, Kurt H.; Rajora, Om P.; Barsi, Debby C.; Kim, K.-H.; Park, J.-M.; Campbell, Moira. 2005. Reproductive barriers and hybridity in two spruces, Picea rubens and Picea mariana, sympatric in eastern North America. Can. J. Bot. 83: 163–175
Keywordscone, seed and seedling traits, genetic variation, phenology, red and black spruce
- Negative heterosis not apparent in 22-year-old hybrids of Picea mariana and Picea rubens
- White spruce meets black spruce: dispersal, postfire establishment, and growth in a warming climate
- Exploring the Alaskan black spruce ecosystem: variability in species composition, ecosystem function, and fire history
XML: View XML