Natural hybridization among closely related spe- cies and divergent selection may lead to adapta- tion to novel habitats and the formation of new species. We investigate the genomic and ecolog- ical mechanisms involved in speciation in pines.The most advanced Scots pine seed orchard (Västerhus) in Sweden.
Hybridization is an important force in plant evolution. It has the potential to quickly generate genetic novelties that promote adaptation and speciation.The evolutionary conse- quences of hybridization are determined by both the intrinsic genetic interactions and environmental selection. To under- stand the relative roles of genetic and ecological components in species diversi cation, we integrate genomic, ecological and functional approaches in comparative studies of hybridizing species that show distinct ecological niche preferences. Cur- rently, we conduct empirical research on the hybrid pine Pinus densata to investigate the genomic patterns of di erentiation and adaptation in pines. Pinus densata is an ancient hybrid spe- cies and forms extensive forest on the Tibetan Plateau. Using this study system, we investigate the genomic architecture of admixed, diverging and divergent populations of the hybrid complex, and how it evolves as diversi cation advances..Marker-based pedigree reconstruction
Effcient use of breeding resources requires a good under- standing of the genetic composition of the founder materials for predicting the gain and diversity in future generations. In Sweden, seed orchard is the link between tree breeding and the production forest. Well-functioning seed orchard is the most cost e cient and realistic way to increase the timber produc- tion from forest land during the coming century. Our research in this area focuses on: 1) the assessment of diversity and coan- cestry in breeding populations of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies); 2) the mating system in seed orchards of the two species; and 3) the adaptation of orchard crops to natural environments. These activities are in close collaboration with Skogforsk.Svensk samanfattning
- Lan, T., Wang, X.-R. & Zeng, Z.-Y. (2013). Structural and functional evolution of positively selected sites in pine GST enzymes. Journal of
- Biological Chemistry 288:24441–24451.
- Torimaru, T., Wennström, U., Lindgren, D. & Wang, X.-R. (2012). Effects of male fecundity, interindividual distance and anisotropic
- pollen dispersal on mating success in a Scots pine (Pinus sylvestris) seed orchard. Heredity 108:312-321.
- Wang, B., Mao, J.-F., Gao, J., Zhao, W. & Wang, X.-R. (2011). Colonization of the Tibetan Plateau by the homoploid hybrid pine Pinus
- densata. Molecular Ecology 20: 3796-3811.
- Mao, J.-F. & Wang, X.-R. (2011). Distinct niche shift characterizes the homoploid hybrid speciation of Pinus densata on the Tibetan
- Plateau. The American Naturalist 177:424-439.
- Wang, X.-R., Torimaru, T., Lindgren, D. & Fries, A. (2010). Marker-based parentage analysis facilitates low input ‘breeding without breeding’ strategies for forest trees. Tree Genetics & Genomes 6: 227-235.
Mating dynamics of Scots pine in isolation tents
TREE GENETICS & GENOMES, 12 (6): DEC 2016
Interspecific Plastome Recombination Reflects Ancient Reticulate Evolution in Picea (Pinaceae)
Mol Biol Evol. 2017, 34 (7):1689-1701
Low rates of pollen contamination in a Scots pine seed orchard in Sweden: the exception or the norm?
SCANDINAVIAN JOURNAL OF FOREST RESEARCH, 2015; 30 (7):573-586
Genetic status of Norway spruce (Picea abies) breeding populations for northern Sweden
SILVAE GENETICA, 2013; 62(3):127-136
Torimaru T, Wennström U, Lindgren D, Wang XR
Effects of male fecundity, interindividual distance and anisotropic pollen dispersal on mating success in a Scots pine (Pinus sylvestris) seed orchard
Heredity: 2012 108(3): 312-321
Shimono A, Wang XR, Torimaru T, Lindgren D, Karlsson B
Spatial variation in local pollen flow and mating success in a Picea abies clone archive and their implications for a novel "breeding without breeding" strategy
Tree Genetics & Genomes: 2011 7:499-509
Hybridization among plants may lead to the formation of new species and adaptation to novel habitats. We investigate the genetic and ecological mechanisms involved in diploid hybrid speciation in pines.
Hybridization is an important force in plant evolution. It can quickly create evolutionary novelties that promote adaptation and speciation. Pinus densata forms extensive forests on the Tibetan Plateau. Documented evidence indicates that P. densata originated via natural hybridization between two other pine species, and dates back to the uplift of the plateau 5-10 million years ago. Its ancient history and unique adaptation offer a rare opportunity to study the genetic basis of speciation. Natural populations of the ancient hybrid, populations at the species’ boundaries and man-made F1 hybrids will be used in comparative analyses. By combining genetic and ecological approaches with molecular functional studies, we are investigating the tempo and mode of the hybrid speciation. This project is relevant to understanding the patterns of functional divergence of gene families and the relationship between genetic variation and ecological diversification. This project is being run in close collaboration with the Institute of Botany, Chinese Academy of Sciences.
The most advanced Scots pine seed orchard (Västerhus) in Sweden.
Marker-based pedigree reconstruction
Pedigree reconstruction is a key to investigating several major issues in genetics and breeding. Accurate pedigree construction and parentage assignment require high-resolution DNA markers and advanced statistical methods. In this project, we explore the possibility to reconstruct sibship structures from wind-pollinated progenies of Scots pine and Norway spruce seed orchards. This research is relevant to evaluating the gene diversity and gain of seed orchard crops, which supply more than 50% of the seedlings used in Swedish forest plantations, and the feasibility of low-input breeding programs in the future. This project is being run in collaboration with the Forest Genetics section (SLU) of UPSC.
Wang, X.-R., Szmidt, A.E. & Savolainen, O. 2001. Genetic composition and diploid hybrid speciation of a high moun- tain pine, Pinus densata, native to the Tibetan plateau. Genetics 159: 337-346.
Song, B.-H., Wang, X.-Q., Wang, X.-R., Ding, K.-Y. & Hong, D.-Y. 2003. Cytoplasmic composition in Pinus densa- ta and population establishment of the diploid hybrid pine. Molecular Ecology 12:2995-3001.
Zeng, Q.-Y. & Wang, X.-R. 2005. Catalytic properties of glutathione-binding residues in a τ class glutathione transferase (PtGSTU1) from Pinus tabulaeformis. FEBS Letters 579: 2657–2662.
Ma, X.-F., Szmidt, A.E. & Wang, X.-R. 2006. Genetic structure and evolutionary history of a diploid hybrid pine Pinus densata inferred from the nucleotide variation at seven gene loci. Molecular Biology and Evolution. 23:807-816.
Mao, J.-F., Li, Y. & Wang, X.-R. 2008. Empirical assessment of the reproductive fitness components of the hybrid pine Pinus densata on the Tibetan Plateau. Evolutionay Ecology, DOI 10.1007/s10682-008-9244-6.
Expand publications list
Torimaru T, Wang X-R, Fries A, Andersson B, Lindgren D
Evaluation of pollen contamination in an advanced Scots pine seed orchard in Sweden
Silvae Genetica: 2009 58:262-269
Wang X-R, Torimaru T, Lindgren D, Fries A
Marker-based parentage analysis facilitates low input "breeding without breeding" strategies for forest trees
Tree Genetics & Genomes: 2010 6:227-235
Yin TM, Wang XR, Andersson B, Kohler EL
Nearly complete genetic maps of Pinus sylvestris L. (Scots pine) constructed by AFLP marker analysis in a full-sib family
Theor Appl Genet: 2003 106:1075-1083
Wang XR, Szmidt AE, Lindgren D
Allozyme Differentiation among Populations of Pinus-Sylvestris (L) from Sweden and China
Hereditas: 1991 114:219-226