Associate Dean, Graduate and Postdoctoral Studies
Research Interests:
Forest Sciences Centre
2424 Main Mall
Vancouver, BC V6T 1Z4
work phone: 6048221821
fax: 6048229102

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 2017

FRST302 Forest Genetics Sections

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

Winter 2017

FRST513 Biotechnology in Tree Improvement Sections

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

Selected Publications

Y. Liu, Y.A. El-Kassaby (2017). Regulatory cross-talk between microRNAs and hormone signalling cascades controls the variation on seed dormancy phenotype at Arabidopsis thaliana seed set Plant Cell Reports • DOI: 10.1007/s00299-017-2111-6
Blaise Ratcliffe, Omnia Gamal El-Dien, Eduardo P. Cappa, Ilga Porth, Jaroslav Klápste, Charles Chen, Yousry A. El-Kassaby (2017). Single-step BLUP with varying genotyping effort in open-pollinated Picea glauca G3: Genes | Genomes | Genetics
Q Wang, W-B Guan, MHG Wong, S Ranjitkar, W-N Sun, Y Pan, YA El-Kassaby, L-X Shen (2017). Tree size predicts vascular epiphytic richness of traditional cultivated tea plantations in Southwestern China Global Ecology and Conservation 10:147–153.
McKown, A.D., Klápště, J., Guy, R.D., Soolanayakanahally, R.Y., La Mantia, J., Porth, I., Skyba, O., Unda, F., Douglas, C.J., El-Kassaby, Y.A., Hamelin, R.C., Mansfield, S.D., Cronk, Q.C.B. (2017). Sexual homomorphism in dioecious trees: extensive tests fail to detect sexual dimorphism in Populus. Scientific Reports 7:1831 DOI:10.1038/s41598-017-01893-z
J-L Feng, Z-J Yang, S-P Chen, YA El-Kassaby, Hui Chen (2017). Signaling pathway in development of Camellia oleifera nurse seedling grafting union Trees Struct. Funct. DOI 10.1007/s00468-017-1568-9
J-L Feng; Z-J Yang; S-P Chen; YA El-Kassaby; Hui Chen (2017). High throughput sequencing of small RNAs reveals dynamic microRNAs expression of lipid metabolism during Camellia oleifera and C. meiocarpa seed natural drying BMC Genomics 18:546 DOI 10.1186/s12864-017-3923-z
J-L Feng, Z-J Yang, W-W Bai, S-P Chen, W-Q Xu, YA El-Kassaby, H Chen (2017). Transcriptome comparative analysis of two Camellia species reveals lipid metabolism during mature seed natural drying Trees Struct. Funct. (in press).
J Song, BF Carver, C Powers, L Yan, J Klápště, YA El-Kassaby, C Chen (2017). Practical application of genomic selection in a doubled-haploid winter wheat breeding program Mol Breed (in press).
R. Du, S. Niu, Y. Liu, X. Sun, I. Porth, YA El-Kassaby and W Li (2017). The gibberellin GID1-DELLA signalling module exists in evolutionarily ancient conifers Scientific Reports (accepted)
Q Wang, L Yang, S Ranjitkar, J-J Wang, X-R Wang, D-X Zhang, Z-Y Wang, Y-Z Huang, Y-M Zhou, Z-X Deng, L Yi, X-F Luan, YA El-Kassaby, W-B Guan (2017). Distribution and in situ conservation of a relic Chinese oil woody species yellowhorn Xanthoceras sorbifolium Bunge Can J For Res (Accepted)
M Lstibůrek, YA El-Kassaby, T Skrøpa, GR Hodge, JH Sønstebø, A Steffenrem (2017). Dynamic gene-resource landscape management of Norway spruce: combining utilization and conservation Frontiers in Plant Science (accepted)
Q Wang, Y Huang, Z Wang, YA El-Kassaby, W Guan (2017). Fruit shape and reproductive self and cross compatibility for the performance of fruit set in an andromonoecious species: Xanthoceras sorbifolium Bunge Tree Genet Genomes (accepted).
Yang Liu and Yousry A. El-Kassaby (2017). Global analysis of small RNA dynamics during seed development of Picea glauca and Arabidopsis thaliana populations reveals insights on their evolutionary trajectories Frontiers in Plant Science (accepted)
E.P. Cappa, Y.A. El-Kassaby, F. Muñoz, M.N. Garcia, P.V. Villalba, J. Klápště, S.N.M.i Poltri (2017). Improving accuracy of breeding values by incorporating genomic information in spatial-competition mixed models Mil Breeding – DOI 10.1007/s11032-017-0725-6
Y. Liu, J.L. Walck and Y.A. El-Kassaby (2017). Roles of the Environment in Plant Life-History Tradeoffs In: Advances in Seed Biology (J. Jimenez-Lopez, ed.). InTech Open Access Publisher. ISBN: 978-953-51-5602-4 (in press)
Park J-M, Kwon S-H, Lee H-J, Na S-J, El-Kassaby YA, Kang K-S (2017). Integrating fecundity variation and genetic relatedness in estimating seed crops genetic diversity: Pinus koraiensis seed orchard as an example Can J For Res 47: 366–37
P Wu, G Wang, YA El-Kassaby, P Wang, X Zou, X Ma. (2017). Solubilization of aluminum-bound phosphorus by root cell walls: evidence from Chinese fir, Cunninghamia lanceolata (Lamb.) Hook. Can J For Res 47:419–423.
El-Kassaby YA, J Klapste (2016). Tree Breeding – Challenges and Opportunities. In: Forestry for the Curious – Why Study Forestry? (K Viadya, ed.), Chapter 7. The Curious Academic Publishing. ISBN: 978-1-925128-52-9.
Korecký J, El-Kassaby YA (2016). Pollination dynamics variation in a Douglas-fir seed orchard as revealed by microsatellite analysis Silva Fennica 50:1682.
Y Liu, S Barot, YA El-Kassaby, N Loeuille (2016). Impact of temperature shifts on the joint evolution of seed dormancy and size Ecology and Evolution DOI: 10.1002/ece3.2611
Y Liu, YA El-Kassaby (2016). Landscape of fluid sets of hairpin-derived 21-/24-nt-long small RNAs at seed set uncovers special epigenetic features in Picea glauca Genome Biology and Evolution 82–92 doi:10.1093/gbe/evw283
Steve Grossnickle and Yousry A. El-Kassaby (2016). Bareroot versus Container Stocktypes: An Ecophysiological Performance Comparison New Forests 47:1-51. DOI 10.1007/s11056-015-9476-6
Y. Liu, T. Wang, and Y. A. El-Kassaby (2016). Contributions of dynamic environmental signals during life-cycle transitions to early life-history traits in lodgepole pine (Pinus contorta Dougl.) Biogeosciences 13:1-14 doi:10.5194/bg-13-1-2016
O. Gamal El-Dien, B. Ratcliffe, J. Klápště, I. Porth, C. Chen, Y.A. El-Kassaby (2016). Implementation of the realized genomic relationship matrix to open-pollinated white spruce family testing for disentangling additive from non-additive genetic effects Genes, Genomes, Genetics DOI: 10.1534/g3.115.025957
Xian-Ge Hu, Hui Liu, YuQing Jin, Yan-Qiang Sun, Yue Li, Wei Zhao, Yousry A. El-Kassaby, Xiao-Ru Wang, Jian-Feng Mao (2016). De novo transcriptome assembly and characterization for the widespread and stress-tolerant conifer Platycladus orientalis PLoS ONE DOI:10.1371/journal.pone.0148985
H. Yuan, S. Niu, Y.A. El-Kassaby, Y. L., W. Li (2016). Simple genetic distance-optimized field deployments for clonal seed orchards based on microsatellite markers: as a case of Chinese pine seed orchard PLoS ONE 11(6): e0157646. doi:10.1371/journal.pone.0157646
X-G Hu, H Liu, J-Q Zhang, Y-Q Sun, Y Jin, W Zhao, YA El-Kassaby, X-R Wang, J-F Mao (2016). Global transcriptome analysis of Sabina chinensis (Cupressaceae), a valuable reforestation conifer Mol Breeding 36:99 DOI 10.1007/s11032-016-0526-3
I. PORTH, P. GARNIER-GÉRÉ, J. KLÁPŠTĔ, C. SCOTTI-SAINTAGNE, Y.A. EL-KASSABY, K. EL BURG, A. KREMER (2016). Species-specific alleles at a β-tubulin gene show significant associations with leaf morphological variation within Quercus petraea and Q. robur populations Tree Genetics and Genomes 12:81 DOI 10.1007/s11295-016-1041-8
Chaloupková, K, J Stejskal, YA El-Kassaby, M Lstibůrek (2016). Optimum neighbourhood seed orchard design Tree Genetics and Genomes 12:105 DOI 10.1007/s11295-016-1067-y
Yang Liu, Kerstin Muller, Yousry A. El-Kassaby, Allison Kermode, (2015). Changes in hormone flux and signaling in white spruce (Picea glauca) seeds during the transition from dormancy to germination in response to temperature cues BMC Plant Biology DOI 10.1186/s12870-015-0638-7
Tony Kess and Yousry A. El-Kassaby (2015). Estimates of pollen contamination and selfing in a coastal Douglas-fir seed orchard Scand J For Res DOI: 10.1080/02827581.2015.1012112
Ilga Porth, Mark Boyland, Suborna Ahmed, Yousry A. El-Kassaby, Gary Bull (2015). Forest Genomics Research and Development in Canada: Priorities for Developing an Economic Framework The Forest Chronicle 91:1-13.
Guibin Wang, Fuliang Cao, Guangyu Wang, Yousry A. El-Kassaby (2015). Role of Temperature and Soil Moisture Conditions on Flavonoid Production and Biosynthesis-Related Genes in Ginkgo (Ginkgo biloba L.) Leaves Nat Prod Chem Res 3:1
Lstibůrek M, J Stejskal, A Misevicius, J Korecký, YA El-Kassaby (2015). Expansion of the minimum-inbreeding seed orchard design to operational scale. Tree Genetics and Genomes 11:12
Yousry A. El-Kassaby, Tomas Funda, Cherdsak Liewlaksaneeyanawin (2015). Increasing Breeding without Breeding (BwB) efficiency: full- vs. partial-pedigree reconstruction in lodgepole pine SOJ Genetic Science 2:1-6.
S Brar, CKM Tsui, B Dhillon, M-J Bergeron, DL Joly, YA El-Kassaby, RC Hamelin (2015). Colonization history, host distribution, anthropogenic influence and landscape features shape populations of white pine blister rust, an invasive alien tree pathogen PLoS ONE DOI:10.1371/journal.pone.0127916
O. Gamal El-Dien, B. Ratcliffe, J. Klápště, C. Chen, I. Porth, Y.A. El-Kassaby (2015). Prediction accuracy of growth and wood attributes of interior spruce in space using genotyping-by-sequencing BMC Genomics DOI 10.1186/s12864-015-1597-y
Porth, I, J Klápště, AD McKown, J La Mantia, RD Guy, PK Ingvarsson, R Hamelin, SD Mansfield, J Ehlting, CJ Douglas, YA El-Kassaby (2015). Evolutionary quantitative genomics of Populus trichocarpa. PLoS ONE DOI:10.1371/journal.pone.0142864
B Ratcliffe, O Gamal El-Dien, J Klápště, I Porth, C Chen, B Jaquish, YA. El-Kassaby (2015). A comparison of genomic selection models across time in interior spruce (Picea engelmannii x glauca) using unordered SNP imputation methods Heredity doi:10.1038/hdy.2015.57
S Niu, H Yuan, X Sun, I Porth, Y Li, YA El-Kassaby, W Li (2015). A transcriptomics investigation into pine reproductive organ development New Phytol DOI: 10.1111/nph.13680
K Demertzis, L Iliadis, S Avramidis, YA El-Kassaby (2015). The use of machine learning in predicting interior spruce wood density utilizing progeny testing information Neural Computing and Applications DOI 10.1007/s00521-015-2075-9
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. (2015). High-resolution genetic mapping of allelic variants associated with cell wall chemistry in Populus BMC Genomics 16:24.
Liu Y, YA El-Kassaby (2015). Timing of seed germination correlated with temperature-based environmental conditions during seed development in conifers. Seed Science Research 25:29-45.
Porth I, YA El-Kassaby (2015). Using poplar as a lignocellulosic feedstock for bioethanol. Biotech J DOI 10.1002/biot.201400194
T Kess, YA El-Kassaby (2014). Jackknife resampling for precision measurement of direct gene flow estimates. Scan J For Res DOI:10.1080/02827581.2014.965196
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 (in press) doi: 10.1111/mec.12969
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
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
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
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 Phytol 203:535-553
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)
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
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
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.
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.
El-Kassaby YA, J Klapste (2014). Genomic selection and clonal forestry revival Proceedings of the Third International Conference of the IUFRO unit 2.09.02 on “Woody Plant Production Integrating Genetic and Vegetative Propagation Technologies“ September 18-12, 2014 ▪ Vitoria-Gasteiz, Spain (Park YS, JM Bonga, eds.). pp. 98-100.
Fundova, I., B. Jaquish and Y.A. El-Kassaby. (2013). Quick wood density assessment using drilling resistance technology NSERC, ForValueNet Res Note No 24.
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
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.
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
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
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.
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.
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.
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.
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
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.
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.
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.
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.
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.
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.
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
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.
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.
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. (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., 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.
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.
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. 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.
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.
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
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.
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.