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Dr. Scott Merkle

Professor, Forest Biology
  • Ph.D. in Forestry - Virginia Polytechnic Institute and State University
  • M.S. in Forestry - Virginia Polytechnic Institute and State University
  • B.S. in Biology - College of William and Mary
Selected Publications:

Merkle, S.A., and Levi, E.M. (Eds). 2023. Proceedings of the 37th Southern Forest Tree Improvement Conference; June 20-23, 2023. Knoxville, TN. 98 p.

Jacobs, D.F., R.K. Dumroese, A.N. Brennan, F.T. Campbell, A.O. Conrad, J.A. Delborne, S. Fitzsimmons, D. Flores, C.P. Giardina, L. Greenwood, J.A. Martin, S.A. Merkle, C.D. Nelson, W.A. Powell, J. Romero-Severson, D.N. Showalter, R.A. Sniezko, S.H. Strauss, J. Westbrook and P. Woodcock. 2023. Reintroduction of at-risk forest tree species using biotechnology depends on regulatory policy, informed by science and with public support. New Forests 54:587–604,

Tull, A.R., H. Gladfelter, F. Pampolini, L. Rieske, C.D. Nelson and S. Merkle. 2022. Development of a new genetic transformation system for white and green ash using embryogenic cultures. Forests 13, 671.

Merkle, S.A., J.L. Koch, A.R. Tull, J.E. Dassow, D.W. Carey, B.F. Barnes, M.W.M. Richins, P.M. Montello, K.R. Eidle, L.T. House, D.A. Herms and K.J.K. Gandhi. 2022. Application of somatic embryogenesis for development of emerald ash borer-resistant white ash and green ash varietals. New Forests. DOI 10.1007/s11056-022-09903-3

Merkle, S.A., and Levi, E.M. (Eds). 2022. Proceedings of the 36th Southern Forest Tree Improvement Conference; June 7-9, 2021. Virtual. 57 p.

Lu, S., and S.A. Merkle. 2021. Enhancing hybrid Liquidambar somatic seedling production using a temporary immersion bioreactor. Trees Structure and Function 35:503-512, DOI 10.1007/s00468-020-02052-0

Gladfelter, H.J., J. Johnston, H.D. Wilde and S.A. Merkle. 2021. Adventitious shoot-based propagation of Franklinia alatamaha for commercial horticulture and restoration. In Vitro Cell. Dev. Biol – Plant 56:857-864,

Gladfelter, H.J., J. Johnston, H.D. Wilde and S.A. Merkle. 2021. Somatic embryogenesis and cryopreservation of Stewartia species. Plant Cell Tiss. Organ Cult. 144:211-221,

Gladfelter, H.J., L.K. Yadav, S.A. Merkle and H.D. Wilde. 2020. Genetic diversity and population structure analysis of Franklinia alatamaha, a tree species existing only in cultivation. Tree Gen. Genomes 16:60. /

Merkle, S.A., F.J. Vieitez, E. Corredoira and J.E. Carlson. 2020. Castanea spp. Chestnut. In: Biotechnology of Fruit and Nut Crops, 2nd Edition (R.E. Litz, F. Pliego-Alfaro and J.I. Hormaza, eds.). CAB International, Wallingford, pp. 206-237.

Gladfelter, H.J., J. Johnston, D. Wilde and S. Merkle. 2019. Somatic embryogenesis of rare Stewartia species and elite cultivars. Combined Proceedings International Plant Propagators’ Society 69:258-256.

Merkle, S.A. 2019. The ups and downs of developing hybrid sweetgum varieties for the U.S. bioenergy and pulp and paper industries: a 20-year case study. In: Bonga JM, Park YS, Trontin JF (Editors) Proceedings of the 5th International Conference of the IUFRO Unit 2.09.02 on “Clonal Trees in the Bioeconomy Age: Opportunities and Challenges.” September 10-15, 2018. Coimbra, Portugal, pp. 225-229.

Zhang, S., P. Bettinger, C. Cieszewski, S. Merkle, K. Merry, S. Obata, X. He and H. Zheng. 2019. Evaluation of sites for the reestablishment of the American chestnut (Castanea dentata) in northeast Georgia, USA. Landscape Ecol. 34:943-960.

Corredoira, E., S.A. Merkle, M.T. Martinez, M. Torribio, J.M. Canhoto, S.I. Correia, A. Ballester and A.M. Vieitez. 2019. Non-zygotic embryogenesis in hardwoods. Critical Reviews in Plant Sciences 38:29-97, DOI: 10.1080/07352689.2018.1551122

Merkle, S.A., A.R. Tull, H.J. Gladfelter, P.M. Montello, J.E. Mitchell, C. Ahn and R.D. McNeill. 2017. Somatic embryogenesis and cryostorage for conservation and restoration of threatened forest trees. In: Sniezko, R. A., Man, G., Hipkins, V., Woeste, K., Gwaze, D.,  Kliejunas, J.T. and McTeague, B.A., tech. cords. Proceedings of Workshop on Gene Conservation of Tree Species–Banking on the Future. Gen. Tech. Rep. PNW-GTR-963. Portland, OR. USDA Forest Service, Pacific Northwest Research Station, pp. 113-116.

Merkle, S.A., C. Ahn, A.R. Tull, P. M. Montello, J.E. Dassow and H.J. Gladfelter. 2017. Integration of selection, breeding, somatic embryogenesis and cryostorage to conserve and restore threatened North American forest trees. In: Proceedings of the Fourth International Conference of the IUFRO Working Party 2.09.02, Development and application of vegetative propagation technologies in plantation forestry to cope with a changing climate and environment. September 19-23, 2016, La Plata, Argentina, pp. 245-248.  

Ahn, C.-H., A.R. Tull, P.M. Montello and S.A. Merkle. 2017. A clonal propagation system for Atlantic white cedar (Chamaecyparis thyoides) via somatic embryogenesis without the use of plant growth regulators. Plant Cell Tiss. Organ Cult. DOI 10.1007/s11240-017-1206-7.

Merkle, S., R. Tull and J. Tubbs. 2017. In vitro propagation of Ozark chinquapin. Journal of The American Chestnut Foundation 31(1):22-24.

Holtz, C.T., A.R. Tull and S.A. Merkle. 2017. Influence of species and hybrid status on induction of somatic embryogenesis in Castanea. Can. J. For. Res. 47(3):382-388. DOI 10.1139/cjfr-2016-0362.

Merkle, S.A., and M. Cunningham. 2016. Application of hybrid breeding and somatic embryogenesis to develop sweetgum varieties for the bioenergy and pulp and paper industries. In: Proceedings of the 33rd Southern Forest Tree Improvement Conference, June 8-11, 2015, Hot Springs, AR, pp. 55-57.

Merkle, S.A. 2016. Application of somatic embryogenesis and transgenic technology to conserve and restore threatened forest tree species. In: Park, Y.-S., Bonga, J.M., and Moon, H.K., eds.) Vegetative Propagation of Forest Trees. National Institute of Forest Science (NIFoS), Seoul, South Korea, pp. 261-278.

Li, H. J. Zhao, J., C. Zhou, S.A. Merkle, and J.-F. Zhang. 2016. Morphologic characters and element content during development of Pinus tabuliformis seeds. J. For. Research 27:67-74. DOI 10.1007/s11676-015-0157-2.

Merkle, S.A., P.M. Montello, H.M. Reece and L. Kong. 2014. Somatic embryogenesis and cryostorage of eastern hemlock and Carolina hemlock for conservation and restoration. Trees Structure and Function 28:1767-1776. DOI 10.1007/s00468-014-1084-0.

Nelson, C.D., W.A. Powell, S.A. Merkle, J.E. Carlson, F.V. Hebard, N. Islam-Faridi, M.E. Staton and L. Georgi. 2014. Biotechnology of trees: chestnut.  In: K. Ramawat, J.M. Merillon, M.R. Ahuja (eds), Tree Biotechnology, Chapter 1. CRC Press, Boca Raton, Florida, USA, pp. 3-35.

Oten, K.L.F., S.A. Merkle, R.M. Jetton, B.C. Smith, M.E. Talley and F.C. Hain. 2014. Understanding and developing resistance in hemlocks to the hemlock woolly adelgid.  Southeastern Naturalist 13:147-167.

Nelson, C.D., W.A. Powell, C.A. Maynard, K.M. Baier, A. Newhouse, S.A. Merkle, C.J. Nairn, L. Kong, J.E. Carlson, C. Addo-Quaye, M.E. Staton, F.V. Hebard, L.L. Georgi, A.G. Abbott, B.A, Olukolu and T. Zhebentyayeva. 2014. The Forest Health Initiative, American chestnut (Castanea dentata) as a model for forest tree restoration: biological research program. In: M.L. Double and W.L. MacDonald (eds), Proceedings of the Fifth International Chestnut Symposium, Acta Hort. 1019:179-189.

Kong, L., C.T. Holtz, C.J. Nairn, H. Houke, W.A. Powell, K. Baier and S.A. Merkle. 2014. Application of airlift bioreactors to accelerate genetic transformation in American chestnut. Plant Cell Tiss. Organ Cult. 117:39-50. DOI 10.1007/s11240-013-0418-8

Li, D., J. Zhang and S.A. Merkle. 2014. Induction of green ash embryogenic cultures with potential for scalable somatic embryo production using suspension culture. Trees Structure and Function 28:253-262. DOI 10.1007/s00468-013-0946-1

Merkle, S.A., A.R. Tull, C.T. Holtz, A. Newman and C.J. Nairn. 2013. Beyond hybrid backcross breeding: the intersection of the American Chestnut Foundation’s breeding program and varietal forestry. In: In: (Cunningham, M.W., ed.) Proceedings of the 32nd Southern Forest Tree Improvement Conference, June 10-13, 2013, Clemson, SC, pp. 64-66.

Holtz, C.T., A.R. Tull and S.A. Merkle. 2013. The influence of Chinese chestnut genome proportion in the success of somatic embryogenesis in chestnut. In: (Cunningham, M.W., ed.) Proceedings of the 32nd Southern Forest Tree Improvement Conference, June 10-13, 2013, Clemson, SC, pp. 55-58.

Merkle, S.A., L. Kong, R. Tull, G. Andrade, P.M. Montello, C.T. Holtz, R. Sakowski, S. Bryson and C.J. Nairn. 2011. Scaling up transgenic American chestnut somatic seedling production for the Forest Health Initiative. In: Proceedings of the 31st Southern Forest Tree Improvement Conference, June 13-16, 2011, Biloxi, MS, pp. 58-60.

Nairn, C.J., L. Kong, G. Andrade-Dean, D.M. Lennon, E. Epps, C.D. Nelson, J.E, Carlson, A. Abbott, T. Kubisiak, C. Maynard, A. Barakat, K. Baier, W.A. Powell and S.A. Merkle. 2011. Delivery and characterization of candidate genes for disease resistance in American chestnut: vector construction and screening. In: Proceedings of the 31st Southern Forest Tree Improvement Conference, June 13-16, 2011, Biloxi, MS, pp. 32-35.

Merkle, S.A. 2011. The case for hardwood varietals:  how hardwood somatic embryogenesis can enhance forest productivity in the Southeastern U.S.  In: Park, Y.S., Bonga, J.M, Park, S.Y., and Moon, H.K. (eds). Proceedings of the IUFRO Working Party 2.09.02: “Somatic Embryogenesis of Trees” conference on “Advances in Somatic Embryogenesis of Trees and Its Application for the Future Forests and Plantations”, August 19-21, 2010, Suwon, Republic of Korea, pp. 37-43.

LeBlanc, M.S. A. Lima, P. Montello, T. Kim, R. B. Meagher and S. Merkle. 2011. Enhanced arsenic tolerance of transgenic eastern cottonwood plants expressing gamma-glutamylcysteine synthetase. Int. J. Phytoremediation 13:657-673.

Merkle, S.A. and M.W. Cunningham. 2011. Southern hardwood varietal forestry:  a new approach to short–rotation woody crops for biomass energy. J. Forestry 109(1):7-14.

Research Areas:
Research Interests:

In vitro propagation of forest trees

Somatic embryogenesis in forest trees

Biotechnology for restoration of threatened tree species


FANR 8200 - Research in Forestry and Natural Resources

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