Head of Department, Forest Resources Management
Professor, Department of Forest and Conservation Sciences
Research Interests:
Forest Sciences Centre
2424 Main Mall
Vancouver, BC V6T 1Z4
work phone: 604-822-1821
fax: 604-822-9102

Research Areas:

  • Tree domestication
  • Tree improvement delivery system
  • Seed orchards’ genetics
  • Tree breeding
  • Association genetics and genomic selection


Development of advanced generation seed orchard designs
In situ wood quality assessment
Seed orchard’s genetic efficiency
Seed dormancy
Association genetics of biofuel attributes
Genomic selection

Unit Associations

Forest Genetics and Breeding
Genetic Data Center GDC

Professional Affiliations

Canadian Institute of Forestry (CIF)
International Union of Forest research Organizations, Divisin 2, Coordinator (IUFRO), Division 2, Coordinator


International Union of Forest Research Organizations Scientific Achievement Award , 2010
Professor Honoris Causa – The Czech University of Life Sciences Praue , 2011

Current Graduate Students

Jeremy DeWaard, PhD
Monitoring biodiversity responses to natural and anthropogenic disturbances in BC’s forests: the application of DNA barcoding (completed)
Manal Fayed, MSc
Metabolite variation in ecologically diverse black cottonwood, Populus trichocarpa Torr. & A. Gray
Tomas Funda, PhD
Population genetics of conifer seed orchards (completed)
Irena Fundova, MSc
In situ wood quality assessment in interior spruce (completed)
Tony Kess, MSc
Reproductive dynamics and fingerprinting effort in a Douglas-fir seed orchard (completed)
Mohamed Ismail, PhD
Molecular genetic diversity among natural populations of Populus (completed)
Chen Ding, MSc
Evaluating interior spruce genetic resource management practices through GIS-based tracking of seed deployment over time and space in British Columbia (completed)
Ben Shu Kwan Lai, MSc
Pollination dynamic in an advanced generation Douglas-fir seed orchard (completed)
Nasim Massah, MSc
Genealogical relationship among members of selection and production populations of yellow-cedar (Callitropsis notkatensis) in the absence of parental information (completed)
Yang Liu, PhD
Genomics of seed dormancy (in progress)
Omniya Gamal, PhD
Genomic selection (in progress)
Blaise Ratcliffe, MSc
Genomic selection (in progress)

Current Courses

Winter 2014

FRST302 Forest Genetics Sections

Population genetics and conservation of genetic resources; principles of genetics and their application to forestry.

Winter 2014

FRST513 Biotechnology in Tree Improvement Sections

Advanced research topics and their application to forest genetics. Emphasis on molecular genetics and experimental protocols.

Selected Publications

Klápšte, J., M. Lstiburek and Y.A. El-Kassaby. (2014). Estimates of genetic parameters and breeding values from western larch open-pollinated families using marker-based relationship Tree Genetics and Genomes 10:241–249 DOI 10.1007/s11295-013-0673-1
Alfaro, R., B. Fady, G.G. Vendramin, I. Dawson, R.A. Fleming, C.Sáenz-Romero, R.A. Lindig-Cisneros, T. Murdock, B. Vinceti, C.M. Navarro, T. Skrøppa, G. Baldinelli, Y.A. El-Kassaby and J. Loo. (2014). The role of forest genetic resources in responding to biotic and abiotic factors in the context of anthropogenic climate change. Forest Ecology and Management doi.org/10.1016/j.foreco.2014.04.006
El-Kassaby, Y.A., M. Fayed, J. Klápště and M. Lstibůrek. (2014). Randomized, replicated, staggered clonal-row (R2SCR) seed orchard design. Tree Genetics and Genomes DOI 10.1007/s11295-014-0703-7
McKown, A.D., J. Klápště, R.D. Guy, A. Geraldes, I. Porth, J. Hannemann, M. Friedmann, W. Muchero, G.A. Tuskan, J. Ehlting, Q.C.B. Cronk, Y.A. El-Kassaby, S.D. Mansfield and C.J. Douglas. (2014). Genome-wide association implicates numerous genes underlying ecological trait variation in natural populations of Populus trichocarpa New Phytologist doi: 10.1111/nph.12815
Porth, I.and Y.A. El-Kassaby (2014). Current status of the development of genetically modified (GM) forest trees world-wide: a comparison with the development of other GM plants in agriculture CAB Reviews 9, No. 008 doi: 10.1079/PAVSNNR20149008
Porth I and YA El-Kassaby (2014). Assessment of the Genetic Diversity in Forest Tree Populations Using Molecular Markers Diversity 6:283-295.
Funda,T., C. Liewlaksaneeyanawin and Y.A. El-Kassaby (2014). Determination of Paternal and Maternal Parentage in Lodgepole Pine Seed: Full versus Partial Pedigree Reconstruction Can. J. For. Res. 44: 1122–1127 (2014) dx.doi.org/10.1139/cjfr-2014-0145
Xu,Y., G. Wang, F. Cao, C. Zhu, G. Wang, Y.A. El-Kassaby (2014). Light Intensity Affects the Growth and Flavonol Biosynthesis of Ginkgo (Ginkgo biloba L.) New Forests DOI 10.1007/s11056-014-9435-7
Muchero W, DiFazio SP, Guo J, Chen J-G, Ranjan P, Slavov GT, Gunter LE, Jawdy S, Bryan AC, Sykes R, Ziebell A, Klápste J, Porth I, Skyba O, Unda F, El-Kassaby YA, Douglas CJ, Mansfield SD, Martin J, Schackwitz W, Evans LM, Czarnecki O, Tuskan GA. (2014). Multi-environment identification of allelic variants associated with cell wall chemistry in Populus. BMC Genomics (accepted)
Korecký J, Lstibůrek M, El-Kassaby YA. (2014). Congruence between theory and practice: Reduced contamination rate following phenotypic pre-selection within the Breeding without Breeding framework. Scand J For Res doi.org/10.1080/02827581.2014.945616
Liu Y, YA El-Kassaby (2014). Timing of seed germination correlated with temperature-based environmental conditions during seed development in conifers. Seed Science Research (accepted)
Porth I, J Klápště, AD McKown, J La Mantia, RD Guy, PK Ingvarsson, R Hamelin, SD Mansfield, J Ehlting, CJ Douglas, YA El-Kassaby (2014). The molecular basis of adaptation to climate in undomesticated Populus trichocarpa. BMC Evolutionary Biology(accepted)
McKowna AD, RD Guy, L Quamme, J Klápště, J La Mantia, CP Constabel, YA El-Kassaby, RC Hamelin, M Zifkin, MS Azam (2014). Association genetics, geography, and ecophysiology link stomatal patterning in Populus trichocarpa with carbon gain and disease resistance trade-offs. Mol Ecol (accepted)
Tsui CK-M, Farfan L, Roe AD, Rice AV, Cooke JEK, El-Kassaby YA, Hamelin RC. (2014). Population structure of mountain pine beetle symbiont Leptographium longiclavatum and the implication on the multipartite beetle-fungi relationships. PLoS ONE 9[8]:e105455
Porth I, YA El-Kassaby (2014). Using poplar as a lignocellulosic feedstock for bioethanol. Biotech J (accepted)
Kess T, YA El-Kassaby (2014). Jackknife resampling for precision measurement of direct gene flow estimates. Scan J For Res (in press) DOI:10.1080/02827581.2014.965196
McKown, A.D., R.D. Guy, J. Klápšte, A. Geraldes, M. Friedmann, Q.C.B. Cronk, Y.A. El-Kassaby, S.D. Mansfield and C.J. Douglas. (2014). Geographical and environmental gradients shape phenotypic trait variation and genetic structure in Populus trichocarpa New Phytologist 201:1263-1276.
Porth, I., J. Klápšte, A.D. McKown, J. LaMantia, R.C. Hamelin, O. Skyba, F. Unda, M.C. Friedmann, Q.C.B. Cronk, J. Ethling, R.D. Guy, S.D. Mansfield, Y.A. El-Kassaby and C.J. Douglas. (2014). Extensive functional pleiotropy of REVOLUTA substantiated through forward genetics Plant Physiology 164:548-554.
Ratcliffe, B., F.J. Hart, J. Klápšte, B. Jaquish, S.D. Mansfield and Y.A. El-Kassaby. (2014). Genetics of wood quality attributes in western larch Annals of Forest Science 71:415-424.
Tony Kess and Yousry A. El-Kassaby (2014). Estimates of pollen contamination and selfing in a coastal Douglas-fir seed orchard Scand J For Res (accepted)
Ilga Porth, Mark Boyland, Suborna Ahmed, Yousry A. El-Kassaby, Gary Bull (2014). Forest Genomics Research and Development in Canada: Priorities for Developing an Economic Framework The Forest Chronicle (accepted)
Steve Grossnickle, Yousry A El-Kassaby (2014). Bareroot versus Container Stocktypes: An Ecophysiological Performance Comparison New Forests (accepted)
Guibin Wang, Fuliang Cao, Guangyu Wang, Yousry A. El-Kassaby (2014). Role of Temperature and Soil Moisture Conditions on Flavonoid Production and Biosynthesis-Related Genes in Ginkgo (Ginkgo biloba L.) Leaves Natural Products Chemistry & Research Journal (accepted)
Fundova, I., B. Jaquish and Y.A. El-Kassaby. (2013). Quick wood density assessment using drilling resistance technology NSERC, ForValueNet Res Note No 24.
El-Kassaby, Y.A., F. Isik and R.W. Whetten. (2013). Modern advances in tree breeding Springer Science+Business Media Dordrecht. DOI 10.1007/978-94-007-7076-8_18 In: (Fenning, T., ed.) Challenges and Opportunities for the World’s Forests in the 21st Century.
Liu Y, A. Kermode, Y.A. EL-Kassaby (2013). The role of moist-chilling and thermo-priming on the germination characteristics of white spruce (Picea glauca) seed Seed Sci. & Technol. 41:1-15
Iliadis, L., S.D. Mansfield, S. Avramidis and Y.A. El-Kassaby (2013). Predicting Douglas-fir wood density by artificial neural networks (ANN) based on progeny testing information. Holzforschung 67:771-777.
Porth, I., J. Klápšte, O. Skyba, M.C. Friedmann, J. Hannemann, J. Ehlting, Y.A. El-Kassaby, S.D. Mansfield and C.J. Douglas (2013). Network analysis reveals the relationship between wood properties, gene expression levels and genotypes of natural Populus trichocarpa accessions -New Phytologist 200:727-742.
Cappa, E.P., Y.A. El-Kassaby, M.N. Garcia, C. Acuña, N.M.G. Borralho, D. Grattapaglia and S.N.M. Poltri. (2013). Impacts of population structure and analytical models in a genome-wide association studies of complex traits in forest trees: A case study in Eucalyptus globulus. PLoS ONE 8:e81267
Geraldes, A., S.P. DiFazio, G.T. Slavov, P. Ranjan, W. Muchero, J. Hannemann, L.E. Gunter, A. Wymore, C. Grassa, N. Farzaneh, I. Porth, A.D. McKown, O. Skyba, E. Li, M. Fujita, J. Klápšte, J. Martin, W. Schackwitz, C. Pennacchio, D.niel Rokhsar, M.C. Friedmann, G.O. Wasteneys, R.D. Guy, Y.A. El-Kassaby, S.D. Mansfield, Q.C.B. Cronk, J. Ehlting, C.J. Douglas, and G.A. Tuskan. (2013). A 34K SNP genotyping array for Populus trichocarpa: Design, application to the study of natural populations and transferability to other Populus species. Molecular Ecology Resources. 13:306-323.
Porth, I., J. Klápšte, O. Skyba, B.S.K. Lai, A. Geraldes, W. Muchero, G.A. Tuskan, C.J. Douglas, Y.A. El-Kassaby and S.D. Mansfield. (2013). Populus trichocarpa cell wall chemistry and ultrastructure trait variation, genetic control and genetic correlations. New Phytologist 197:777-790.
Korecky, J., J. Klapste, M. Lstiburek, J. Kobliha, C.D. Nelson and Y.A, El-Kassaby. (2013). Comparison of genetic parameters from marker-based relationship, sib-ship and combined models in Scots pine multi-site open-pollinated tests. – Tree Genetics and Genomes 9:1227-1235. Tree Genet. Genomes (in press). DOI 10.1007/s11295-013-0630-z
Baltunis B.S., J.H. Russell, A. Van Niejenhuis, J. Barker and Y.A. El-Kassaby. (2013). Genetic analysis and clonal stability of two yellow cypress clonal populations in British Columbia Silvae Genetica 62:173-187.
Chen, C., S.E. Mitchell, R.J. Elshire, E.S. Buckler and Y.A. El-Kassaby. (2013). Mining conifers’ mega-genome using rapid and efficient multiplexed high-throughput genotyping-by-sequencing (GBS) SNP discovery platform. -Tree Genetics and Genomes DOI 10.1007/s11295-013-0657-1
Bao, H. , E. Li, S.D. Mansfield, Q.C.B. Cronk, Y.A. El-Kassaby and C.J. Douglas. (2013). The developing xylem transcriptome and genome-wide analysis of alternative splicing in Populus trichocarpa (black cottonwood) populations -BMC Genomics 14:359
Porth, I., J. Klapste, O. Skyba, J. Hannemann, A.D. McKown, R.D. Guy, S.P. DiFazio, W. Muchero, P. Ranjan, G.A. Tuskan, M.C. Friedmann, J. Ehlting, Q.C.B. Cronk, Y.A. El-Kassaby, C.J. Douglas and S.D. Mansfield (2013). Genome-wide association mapping for wood characteristics in Populus identifies an array of candidate single nucleotide polymorphisms. -New Phytologist 200:710-726.
La Mantia, J., J. Klápšte, Y.A. El-Kassaby, S. Azam, R.D. Guy, C.J. Douglas, S.D. Mansfield, and R. Hamelin (2013). Association analysis identifies Melampsora x columbiana poplar leaf rust resistance SNPs PLoS ONE 8:e78423
Lstiburek, M.; J. Klaste; J. Kobliha and Y.A. El-Kassaby. (2012). Breeding without Breeding: Effect of gene flow on fingerprinting effort -Tree Genetics and Genomes 8:873-877.
Funda, T and Y.A. El-Kassaby (2012). Seed Orchards Genetics -CAB Reviews 7, No. 013 doi: 10.1079/PAVSNNR20127013
Wang, J., Y.A. El-Kassaby and K. Ritland. (2012). Estimating selfing rates from reconstructed pedigrees using multilocus genotype data. Mol. Ecol. 21:100-116.
Tsui, C.K.M., A.D. Roe, Y.A. El-Kassaby, A.V. Rice, S.M. Alamouti, F.A.H. Sperling, J.E.K. Cooke, J. Bohlmann and R.C. Hamelin. (2012). Population structure and migration pattern of a conifer pathogen, Grosmannia clavigera, as influenced by its symbiont the mountain pine beetle. -Mol. Ecol. 21:71-86.
Ding, C., L. McAuley, M.J. Meitner, Y.A. El-Kassaby. (2012). Evaluating interior spruce seed deployment with GIS-based modeling using British Columbia’s Prince George Seed Planning Zone as a model. -Silvae Genet. 61:271-279.
Tomas Funda, Milan Lstiburek, Jaroslav Klápšte, Yousry A. El-Kassaby (2012). OPTIMIZATION OF GENETIC GAIN AND DIVERSITY IN SEED ORCHARD CROPS CONSIDERING GERMINATION VARIATION -Scand. J. For. Res. 27:787-793.
M. Ismail, R.Y. Soolanayakanahally, P.K. Ingvarsson, R.D. Guy, S. Jansson, S.N. Silim and Y.A. El-Kassaby (2012). Comparative nucleotide diversity across North American and European Populus species -J. Mol. Evol. 74:257-272.
Yousry A. El-Kassaby, Jaroslav Klápšte and Robert D. Guy (2012). Breeding without Breeding: selection using the genomic best linear unbiased predictor method (GBLUP) -New Forests 43:631-637.
Slavov, G.T., DiFazio, S.P., Martin, J., Schackwitz, W., Muchero, W., Rodgers-Melnick, E., Lipphardt, M.F., Pennacchio, C.P., Hellsten, U., Pennacchio, L., Gunter, L.E., Ranjan, P., Vining, K., Pomraning, K.R., Wilhelm, L.J., Pellegrini, M., Mockler, T., Freitag, M., Geraldes, A., El-Kassaby, Y.A., Mansfield, S.D., Cronk, Q.C.B., Douglas, C.J., Strauss, S.H., Rokhsar, D., Tuskan. G.A. (2012). Genome resequencing reveals multiscale geographic structure and extensive linkage disequilibrium in the forest tree Populus trichocarpa. New Phytologist. 196:713–725.
El-Kassaby, Y.A. (2012). Breeding without breeding: From no pedigree to pedigree-free model. -Lee, H. et al. (eds.), International Symposium Commemorating the 100th Anniversary of Dr. S.K. Hyun’s Birth. Seoul, Korea (Feb. 21, 2012). pp. 61-71.
Stoehr, MU and Y.A. El-Kassaby (2011). Challenges facing the forest industry in relation to seed dormancy and seed quality -Springer Science+Business Media, LLC 2011 -Allison R. Kermode (ed.), Seed Dormancy: Methods and Protocols, Methods in Molecular Biology, vol. 773, DOI 10.1007/978-1-61779-231-1_1, Chapter 1. pp 3-15.
Lstiburek, M, K. Ivanková, J. Kadlec, J. Kobliha, J. Klápšte, Y.A. El-Kassaby. (2011). Breeding without breeding: minimum fingerprinting effort with respect to the effective population size. -Tree Genetics and Genomes 7:1069-1078.
El-Kassaby, Y.A., E.P. Cappa, C. Liewlaksaneeyanawin, J. Klápšte and M. Lstiburek. (2011). Breeding without breeding: is a complete pedigree necessary for efficient breeding? -PLoS ONE 6(10): e25737. doi:10.1371/journal.pone.0025737.
Cappa, E.P., M. Lstiburek, A.D. Yanchuk and Y.A. El-Kassaby. (2011). Two-dimensional penalized splines via Gibbs sampling to account for spatial variability in forest genetic trials with small amount of information available. -Silvae Genet. 60:25-35.
Tomas Funda, Cherdsak Liewlaksaneeyanawin, Irena Fundova, Ben S.K. Lai, Chris G. Walsh, Annette Van Niejenhuis, Cathy Cook, Hilary Graham, Michael U. Stoehr, Jack Woods, and Yousry A. El-Kassaby (2011). Congruence between clonal reproductive investment and success as revealed by DNA-based pedigree reconstruction in conifers seed orchards - Can. J. For. Res. 41: 380–389.
El-Kassaby, Y. A., Mansfield, S. D., Isik, F., Stoehr, M. (2011). In situ wood quality assessment in Douglas-fir Tree Genetics and Genomes 7:553-561.
Lstiburek, M. and Y.A. El-Kassaby. (2010). Minimum-Inbreeding Seed Orchard Design -For. Sci. 56:603-608.
Kang, K.S., C.S. Kim and Y.A. El-Kassaby. (2010). Clonal variation in acorn production and its effect on effective population size in a Quercus acutissima seed orchard. -Silvae Genet. 59:170-175.
Yousry A. El-Kassaby, Tomas Funda, and Ben S.K. Lai (2010). Female Reproductive Success Variation in a Pseudotsuga menziesii Seed Orchard as Revealed by Pedigree Reconstruction from a Bulk Seed Collection -J Hered. 101:164-168.
B S LAI, T FUNDA, C LIEWLAKSANEEYANAWIN, J KLAPSTE, A VAN NIEJENHUIS, C COOK, M U STOEHR, J WOODS, Y A EL-KASSABY (2010). Pollination Dynamics in a Douglas-fir Seed Orchard as Revealed by Pedigree Reconstruction -Annals of Forest Science 67. DOI: 10.1051/forest/2010044
El-Kassaby, Y.A. and J.A. Prado (eds.) (2010). Forests and genetically modified trees -Food and Agriculture Organization of the United nations, Rome, Italy. 235pp.
El-Kassaby, Y.A. (2010). Pedigree Reconstruction: An Alternative to Systematic Breeding. - In: Molecular Approaches in Natural Resource Conservation and Management (DeWoody, J.A. et al., eds). Cambridge University Press. 285-286pp.
Massah, N., J. Wang, J.H. Russell, A. van Niejenhuis and Y.A. El-Kassaby. (2010). Genealogical relationship among members of selection and production populations of yellow-cedar (Callitropsis nootkatensis) in the absence of parental information. J. Hered. 101:154-163.
B. Bains, F. Isik, W. Strong, B. Jaquish, J.A. McLean, and Y.A. El-Kassaby. (2009). Genetic resistance of spruce to gall forming adelgids (Hemiptera: Adelgidae). - Can. J. For. Res. 39:2536-2541.
El-Kassaby, Y.A. and M. Lstiburek (2009). Breeding without breeding -Genet. Res. 91:111-120.
El-Kassaby,Y.A., D. Kolotelo and D. Reid (2009). Understanding Lodgepole Pine Seed Germination for Improved Utilization -Seed Sci. & Tech. 37: 316-328.
Ding, C., Meitner, M., El-Kassaby, Y., and McAuley, L. (2009). GIS-based forest seed deployment tracking over time and space. In Proceedings, 2009 ESRI International Users conference, July 2009, San Diego, California. (CD), ESRI Press.
T. Funda, M. Lstiburek, P. Lachout, J. Klapste, Y.A. El-Kassaby (2009). GENETIC GAIN-DIVERSITY OPTIMIZATION FOR SEED ORCHARD CROPS -Tree Genetics and Genomes DOI 10.1007/s1 1295-009-0211-3
El-Kassaby, Y.A., I. Moss, D. Kolotelo and M. U Stoehr. (2008). Seed germination: mathematical representation and parameters extraction. -For. Sci. 54:220-227.
Lstiburek, M. and Y.A. El-Kassaby (2008). Advanced-Generation Seed Orchard Designs -In Lindgren D (editor). Proceedings of a Seed Orchard Conference, Umeå, 26-28 September, 2007. http://www-genfys.slu.se/staff/dagl/Umea07/Proceedings/LstiburekDesign.pdf
El-Kassaby, Y.A. (2008). Breeding without breeding: an unorthodox concept. -In: Adaptation, Breeding and Conservation in the Era of Forest Tree Genomics and Environmental Change. IUFRO-CTIA 2008 Joint Meeting, Quebec City (Bousquet, J. and J.D. Simpsom, eds.). pp. 4-8.
C. Chen, C. Liewlaksaneeyanawin, T. Funda, A. Kenawy, C.H. Newton and Y.A. El-Kassaby (2008). Development and characterization of microsatellite loci in western larch (Larix occidentalis Nutt.) -Mol. Ecol. Res. 9:843-845.
Funda, T., C. Chen, C. Liewlaksaneeyanawin, A. Kenawy, and Y.A. El-Kassaby (2008). Pedigree and Mating System Analyses in a Western Larch (Larix occidentalis Nutt.) Experimental Population -Ann. For. Sci. 65:705. DOI:10.1051/forest:2008055
El-Kassaby, Y.A., M.U Stoehr, D. Reid, C.G. Walsh and T.E. Lee. (2007). Clonal-row vs. random seed orchard designs: interior spruce mating system evaluation. - Can. J. For. Res. 37:690-696.
El-Kassaby, Y.A. and D. Lindgren. (2007). Increasing the efficiency of Breeding Without Breeding through phenotypic pre-selection in open pollinated progenies. -In: Joint Meeting of the South. For. Tree Improve. Conf. and the Western For. Genetics Association, June, 2007. Galveston, Taxes. pp 15-19.
El-Kassaby, Y.A. and D. Reid. (2007). Is randomization necessary in seed orchards? - In: Joint Meeting of the South. For. Tree Improve. Conf. and the Western For. Genetics Association, June, 2007. Galveston, Taxes. pp 63-67.
El-Kassaby, Y.A. and S.D. Mansfield (2007). The use of genetically modified trees in forests: opportunities and challenges -In: Challenges and Opportunities of Forest Research in the Policy Making Process. The Chinese Academy of Forestry (CAF) and the International Union of Forest Research Organizations (IUFRO) Symposium, Beijing, PRC (May 29, 2007). pp. 2-13.
El-Kassaby,Y.A., M. Lstiburek, C. Liewlaksaneeyanawin, G.T. Slavov and G.T. Howe. (2007). Breeding without breeding: approach, example, and proof of concept. -In: Proc. IUFRO, Low input breeding and genetic conservation of forest tree species. Antalya, Turkey. pp. 43-54. http://www.akdeniz.edu.tr/english/iufro/2007.pdf
El-Kassaby, Y.A., F. Perscher, F. and D. Lindgren. (2007). Advanced generation seed orchards turnover as affected by breeding advance, time to sexual maturity, and costs: special reference to Pinus sylvestris in Sweden. -Scand. J. For. Res. 22:88-98.
M. Lstiburek, C. D. Nelson, C. S. Echt, T. J. Mullin, Y. A. El-Kassaby, and R. Pong-Wong (2007). Computer simulation of marker-directed population improvement -In: Joint Meeting of the South. For. Tree Improve. Conf. and the Western For. Genetics Association, June, 2007. Galveston, Taxes. pp 56-59.
Perscher, F., D. Lindgren and Y.A. El-Kassaby, Y.A. (2006). Is linear deployment of clones optimal under different clonal outcrossing contributions in seed orchards? - Tree Genetics and Genomics 2:25-29.
Lstiburek, M., T. Mullin and Y.A. El-Kassaby. (2005). The impacts of positive assortative mating, differential success of somatic embryogenesis, and multi-trait selection on the outcome of clonal forestry programs. - Can. J. For. Res. 36:1376-1384.
El-Kassaby Y.A., K. Ritland, C.E. Ritland, S.N. Aitken, J. Bohlmann, and J. Krakowski. (2005). Forest genetics. -In: Forestry handbook (S.B. Watts and L. Tolland, eds.), 5th ed. Faculty of Forestry, The University of British Columbia, Vancouver, BC. 474-486pp.
El-Kassaby, Y.A. and J. Krakowski. (2005). Forest biotechnology deliverables: availability and benefits. -In: North American Conf. on forest biotechnology. New Century, New Trees: Biotechnology as a Tool for Forestry in North America (McCord, S. and R. Kellison, eds.), Nov. 16-17, Research Triangle Park, S.C., USA. 53-69pp.
Kang, K.S., Y.A. El-Kassaby, S.U. Han, and C.S Kim. (2005). Genetic gain and diversity under different thinning scenarios in a breeding seedling seed orchard of Quercus accutissima. For. Ecol. Manage. 212:405-410.
Krakowski, J, A. Benowicz, J.H. Russell and Y.A. El-Kassaby. (2005). Effects of serial propagation, donor age and genotype on Chamaecyparis nootkatensis physiology and growth traits. Can. J. For. Res. 35:623-632.
Krakowski, J. and Y.A. El-Kassaby. (2005). Lodgepole pine and white spruce germination: effects of stratification and simulated aging. Silvae Genet. 54:138-144.
Beland, J.D., J. Krakowski, C.E. Ritland, K. Ritland, and Y.A. El-Kassaby. (2005). Genetic structure and mating system of northern Arbutus menziesii populations. Can. J. Botany 83:1581-1589.
Krakowski, J., Y.S. Park, and Y.A. El-Kassaby. (2005). Early testing of Douglas-fir: wood density and ring width. For. Genet. 12:99-105.
Kang, K.S., Y.A. EL-Kassaby, M.S. Chung, C.S. Kim, Y.J. Kang and B.S. Kang. (2005). Fertility variation and effective number in a clonal seed orchard of Cryptomeria japonica. Silvae Genet. 54:104-107.
Ritland, K., M.D. Meagher, D.G.W. Edwards and Y.A. El-Kassaby. (2005). Isozyme variation and the conservation genetics of Garry oak. Can. J. Bot. 83:1478-1487.
Wilkin, J.E., S.F. Shamoun, C.E. Ritland, K. Ritland, and Y.A. El-Kassaby. (2005). Population genetics of Gaultheria shallon in British Columbia and the implications for management using biocontrol. Can. J. Bot. 83:501-509.
El-Kassaby, Y.A. and G.R. Askew. (2004). A method for estimating expected genetic diversity of vegetatively propagated populations produced from commonly used mating designs. -In: Plantation forest biotechnology for the 21st century (Walter, C. and M. Carson, eds). Research Signpost, Kerala, India. pp. 129-146.
El-Kassaby, Y.A., A. Benowicz, and D.G.W. Edwards. (2004). Genetic variation in germination attributes and response to accelerated aging in western hemlock seeds. Seed Technol. 26:38-50.
El-Kassaby, Y.A. and J. Krakowski. (2004). Methods of cloning forest trees. In: Forest genetics and tree breeding in the age of genomics: progress and future, IUFRO Joint Conf. Div. 2. Li, B. and S. McKeand, eds. Nov. 16-17, Research Triangle Park, S.C., USA. pp. 327-332.
El-Kassaby, Y.A. and I. Moss. (2004). Clonal forestry: options, deliverables and benefits. In: Forest genetics and tree breeding in the age of genomics: progress and future, IUFRO Joint Conf. Div. 2. Li, B. and S. McKeand, eds. Nov. 16-17, Research Triangle Park, S.C., USA. pp. 55-64.
Sutton, B.C.S., S.M. Attree, Y.A. El-Kassaby, S.C. Grossnickle, and D.R. Polonenko. (2004). Commercialisation of somatic embryogenesis for plantation forestry. Plantation forest biotechnology for the 21st century (Walter, C. and M. Carson, eds). Research Signpost, Kerala, India. pp. 275-301.
Liewlaksaneeyanawin, C., Ritland, C., El-Kassaby, Y.A. and Ritland, K. (2004). Single-copy, species-transferable microsatellite markers developed from loblolly pine ESTs. Theor. Appl. Genetics 109: 361-369
(2004). Comparative nucleotide diversity across North American and European Populus species
(2004). Playing the forest
(2004). Effect of water sparay on poor people
El-Kassaby, Y.A. (2003). Clonal-row vs. random seed orchard designs: mating pattern and seed yield of western hemlock (Tsuga heterophylla (Raf.) Sarg.). For. Genet. 10:121-127.
El-Kassaby, Y.A., B.G. Dunsworth, and J. Krakowski. (2003). Genetic evaluation of alternative silvicultural systems in coastal montane forests: western hemlock and amabilis fir. Theor. Appl. Genet. 107:598-610.
Kang, K.S., Y.A. El-Kassaby, W.Y. Choi, S.U. Han, and C.S. Kim. (2003). Changes in genetic gain and diversity caused by genetic thinning in a clonal seed orchard of Pinus densiflora. Silvae Genet. 52:220-223.
Krakowski, J., S.N. Aitken, and Y.A. El-Kassaby. (2003). Inbreeding and conservation genetics in whitebark pine. Cons. Genet. 4:581-593.
Krakowski, J. and Y.A. El-Kassaby. (2003). Effects of stratification and simulated aging on germination of Douglas-fir seed from a clonal seed orchard. For. Genetics 10:65-70.
Krakowski, J. and Y.A. El-Kassaby. (2003). Impacts of alternative silviculture systems on the genetic diversity and mating systems of forest tree species. In: Silviculture and conservation of genetic resources for sustainable forest management. Proc. symp. N. Amer. For. Comm., Forest Genetic Res. and Silv. Working Groups, and IUFRO World Congress, Quebec City, PQ. Nat. Res. Canada, Can. For. Serv. Info. Rep. LAU-X-128 pp. 75-87.
Liewlaksaneeyanawin, C., C.E. Ritland, K. Ritland, and Y.A. El-Kassaby. (2003). Experimental analysis of the mating system of the white pine weevil, Pissodes strobi (Peck) (Coleoptera: Curculionidae). Can J. Zool. 81:424-429.
Benowicz, A., S.C. Grossnickle and Y.A. El-Kassaby. (2002). Field assessment of Douglas-fir somatic and zygotic seedlings with respect to gas exchange, water relations and frost hardiness. Can. J. For. Res. 32:1-7.
Liewlaksaneeyanawin, C., C.E. Ritland and Y.A. El-Kassaby. (2002). Inheritance of microsatellites in the white pine weevil, Pissodes strobi (Peck) (Coleoptera: Curculionidae). J. Hered. 93:67-70.
Cherry, M.I. and Y.A. El-Kassaby. (2002). Performance of yellow-cedar (Chamaecyparis nootkatensis) seedlings originating from an abbreviated reproductive cycle. Can. J. For. Res. 32: 52-58.
Kang, K.-S. and Y.A. El-Kassaby. (2002). Theoretical and applied considerations of correlated fertility between genders on genetic diversity: Pinus densiflora seed orchard as a model. Theor. Appl. Genet. 105:1183-1189.
Lewis, K.G., C. Liewlaksaneeyanawin, R.I. Alfaro, C. Ritland, K. Ritland, and Y.A. El-Kassaby. (2002). Sexual reproduction in the white pine weevil, Pissodes strobi (Peck) (Coleoptera: Curculionidae): Implications for population genetic diversity. J. Hered. 93:165-169.
El-Kassaby, Y.A., A. Benowicz, and D.G.W. Edwards. (2002). Genetic control of germination and aging: lessons for practice and conservation. In: 2002 IUFRO 2.09.00, Res.h Group for Seed Physiol. and Technol. Tree Seeds 2002. Thanos, C.A. et al. (eds.) Chania, Crete, Greece. pp. 70-78.
Namkoong, G., T. Boyle, Y.A. El-Kassaby, C. Palmberg-Lerche, G. Eriksson, H.-R. Gregorius, H. Joly, A. Kremer, O. Savolainen, R. Wickneswari, A. Young, M. Zeh-Nlo, and R. Prabhu. (2002). Criteria and indicators for sustainable forest management: assessment and monitoring of genetic variation. -Forest Genetic Resources Working Paper FGR/37E, For. Res. Dev. Serv., FAO, Rome, Italy. 29 pp.
Xie, C.-Y., Y.A. El-Kassaby, and C.C. Ying. (2002). Genetics of red alder (Alnus rubra Bong.) populations in British Columbia and its implications for gene resources management. -New For. 24:97-112.
Alfaro, R.I., J.N. King, Y.A. El-Kassaby, R.G. Brown and K.G. Lewis. (2001). Use of artificial infestations in the selection of Sitka spruce genotypes for resistance to the white pine weevil in British Columbia, Canada. -In: X Protection of World Forests from Insect Pests: Advances in Research, XI IUFRO World Congress, Kuala Lumpur, Malaysia. Can. For. Serv. Publ. ISSN 1016-3263. pp. 13-18.
Benowicz, A., Y.A. El-Kassaby, R.D. Guy, and M.R. Carlson. (2001). Genetic variation among paper birch (Betula papyrifera marsh.) populations in germination, frost hardiness, gas exchange and growth. -Silvae Genet. 50:7-13.
Benowicz, A., S. L’Hirondelle, and Y.A. El-Kassaby. (2001). Patterns of genetic variation in mountain hemlock with respect to height growth and frost hardiness. -For. Ecol. Manage. 154:23-33.
Cyr, D.R., S.M. Attree, Y.A. El-Kassaby, D.D. Ellis, D.R. Polonenko and B.C.S. Sutton. (2001). Application of somatic embryogenesis to tree improvement in conifers. In: Molecular breeding of woody plants. -In: Molecular breeding of woody plants. (Morohoshi, N. and A. Komamine, eds). Elsevier, The Netherlands. pp. 305-312.
El-Kassaby, Y.A. (2001). Genetic improvement and somatic embryogenesis. -Seed and Seedling Extension Topics, BC Min. For., Ext. Serv., Tree Improvement. 13(2):12-16.
El-Kassaby, Y.A., R.I. Alfaro, J.N. King, C.C. Ying, A.D. Yanchuk, and I Leal. (2001). Somatic embryogenesis as a delivery system for specialty products with reference to resistant Sitka spruce to the white pine weevil. -Proc. 26th South. For. Tree Improve. Conf., June, 2001. Athens, GA. pp. 154-168.
El-Kassaby, Y.A. and D.G.W. Edwards. (2001). Germination ecology in mountain hemlock (Tsuga mertensiana (Bong.) Carr.). -For. Ecol. Manage. 144:183-188.
El-Kassaby, Y.A. and I. Moss. (2001). The economic benefits of planting weevil resistant sitka spruce through somatic embryogenesis. -In: Proc. 26th South. For. Tree Improve. Conf., June, 2001. Athens, GA. pp. 48-59.
Lewis, K.G., K. Ritland, Y.A. El-Kassaby, J.A. McLean, J. Glaubitz, and J.E. Carlson. (2001). Randomly amplified polymorphic DNA (RAPD) reveals fine-scale genetic structure Pissodes strobi (Coleoptera: Curculionidae). -Can. Entomol. 133:229-238.
Liewlaksaneeyanawin, C., C.E.Ritland, C.H Newton, and Y.A. El-Kassaby. (2001). Characterization of microsatellite loci in white pine weevil (Pissodes strobi). -Mol. Ecol. Notes 1:248-249.
Viard, F., Y.A. El-Kassaby and K. Ritland. (2001). Diversity and genetic structure in populations of Pseudotsuga menziesii (Pinaceae) at chloroplast microsatellite loci. -Genome 44:336-344.
Alfaro, R.I., K.G. Lewis, J.N. King, Y.A. El-Kassaby, G. Brown, and L.D. Smith. (2000). Budburst phenology of Sitka spruce and its relationship to white pine weevil attack. -For. Ecol. Manage. 127:19-29.
Benowicz, A., Y.A. El-Kassaby, R.D. Guy, and C.C. Ying. (2000). Sitka alder (Alnus sinuata Rydb.) genetic diversity in germination, frost hardiness and growth attributes. -Silvae Genet. 49:206-212.
Sutton, B., S. Attree, Y.A. El-Kassaby and D. Cyr. (2000). Clonal propagation and tree improvement using somatic embryogenesis. -In: Proc. TAPPI, Pulping/Process and Product Quality, Nov. 5-8, 2000. Boston, MA.
Ally, D., A., K. Ritland, and Y.A. El-Kassaby. (2000). Genetic diversity, differentiation, inbreeding and gene conservation of mountain hemlock (Tsuga mertensiana) from British Columbia -For. Genet. 7:97-108.
Benowicz, A., R.D. Guy and Y.A. El-Kassaby. (2000). Geographic pattern of genetic variation in photosynthetic capacity and growth in two hardwood species from British Columbia. Oecologia 123:168-174.
El-Kassaby, Y.A. (2000). Representation of Douglas-fir and western hemlock families in seedling crops as affected by seed biology and nursery crop management practices. For. Genetics 7:305-315.
El-Kassaby, Y.A. (2000). Effect of forest tree domestication on gene pools. In: Forest Conservation Genetics: Principles and Practice. (Young, A., D. Boshier and T. Boyle, eds.). Commonwealth Scientific and Industrial Research Organisation (CSIRO). CSIRO Publishing-CABI Publishing, Canberra, Australia. 13:197-213.
El-Kassaby, Y.A. (2000). Impacts of industrial forestry on genetic diversity of forest trees. In: Forest Genetics and Sustainability.Kluwer Academic Publishers. The Netherlands (Matyas, C. ed.). 63:155-169.
El-Kassaby, Y.A. and A. Benowicz. (2000). Effects of commercial thinning on genetic, plant species and structural diversity in second growth Douglas-fir (Psudotsuga menziesii (Mirb.) Franco) stands. For. Genetics. 7:193-203.
Glaubitz, J.C., Y.A. El-Kassaby and J. Carlson. (2000). Nuclear restriction fragment length ploymorphism analysis of genetic diversity in western red cedar. Can. J. For. Res. 30:379-389.
Lewis, K.G., Y.A. El-Kassaby, R.I. Alfaro and S. Barnes. (2000). Population genetic structure of Pissodes strobi (Coleoptera: Curculionidae) in British Columbia, Canada. Ann. Entomol. Soc. Am. 93:807-818.
Xu, P., C.C. Ying and Y.A. El-Kassaby. (2000). Multivariate approaches for determining the underlying major ecological factors characterizing growth of 43 Sitka spruce populations. Silvae Genet. 49:257-263.
Benowicz, A. and Y.A. El-Kassaby. (1999). Genetic variation in mountain hemlock (Tsuga mertensiana Bong.): quantitative and adaptive attributes. For. Ecol. Manage. 123:205-215.
El-Kassaby, Y.A. (1999). Phenotypic plasticity in western redcedar. For. Genetics 6:235-240.
El-Kassaby, Y.A. and G.R. Askew. (1998). Seed orchards and their genetics. In: Forest Genetics and Tree Breeding (Mandal, A.K. and G.L. Gibson, eds.). CBS Publishers abd Distributors, New Delhi, India. 6:103-111.
El-Kassaby, Y.A. and Edwards, D.G.W. (1998). Genetic control of germination and the effects of accelerated aging in mountain hemlock seeds and its relevance to gene conservation. For. Ecol. Manage. 112:203-211.
-EL-KASSABY, Y.A. and K. RITLAND. (1998). Isozymes: techniques, interpretation and applications to forest genetics. In: Mandal, A.K. and G.L. Gibson (eds.). CBS Publishers abd Distributors, New Delhi, India Forest Genetics and Tree Breeding.12:213-226.
Jaquish, B. and Y.A. El-Kassaby. (1998). Genetic variation of western larch in British Columbia and its conservation. J. Hered. 89:248-253.
Hamann, A., Y.A. El-Kassaby, M.P. Koshy and G. Namkoong. (1998). Multivariate analysis of allozymic and quantitative trait variation in Alnus rubra: geographic patterns and evolutionary implications. Can. J. For. Res. 28: 1557-1565.
El-Kassaby, Y.A. and K. Ritland. (1998). Isozymes: techniques, interpretation and applications to forest genetics In: Forest Genetics and Tree Breeding (Mandal, A.K., ed.). CBS Publishers and Distributors, New Delhi. pp.213-226.
El-Kassaby, Y. A. and Ritland, K. (1996). Genetic variation in low elevation Douglas-fir of British Columbia and its relevance to gene conservation. Biodiversity and Conservation 5:779-794.
El-Kassaby, Y.A. and Ritland, K. (1996). Impact of Selection and Breeding on the Genetic Diversity in Douglas-fir. Biodiversity and Conservation 5:795-813.