Abstract
Walnut species are important nut and timber producers in temperate regions of Europe, Asia, South America, and North America. Trees can be impacted by Phytophthora, crown gall, nematodes, and cherry leaf roll virus; nuts can be severely damaged by codling moth and Xanthomonas blight. The long-generation time of walnuts and an absence of identified natural resistance for most of these problems suggest biotechnological approaches to crop improvement. Described here is a somatic embryo based transformation protocol that has been used to successfully insert horticulturally useful traits into walnut. Selection is based on the combined use of the selectable neomycin phosphotransferase (nptII) gene and the scorable uidA gene. Transformed embryos can be germinated or micropropagated and rooted for plant production. The method described has been used to establish field trials of mature trees.
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References
McGranahan, G.H., Tulecke, W., Arulsekar, S., and Hansen, J.J. (1986) Intergeneric hybridization in the Juglandaceae: Pterocarya sp. x Juglans regia. J. Amer. Soc. Hort. Sci. 111, 627–30.
Driver, J.A. and Kuniyuki, A.H. (1984) In vitro propagation of Paradox walnut (Juglans hindsii × Juglans regia) rootstock. Hortscience 19, 507–09.
McGranahan, G.H., Leslie, C.A., and Driver, J.A. (1988) In Vitro Propagation of Mature Persian Walnut Cultivars. Hortscience 23, 220.
Tulecke, W. and McGranahan, G.H. (1985) Somatic embryogenesis and plant regeneration from cotyledons of walnut, Juglans regia L. Plant Science (Limerick) 40, 57–64.
Tulecke, W., McGranahan, G.H., and Ahmadi, H. (1988) Regeneration by somatic embryogenesis of triploid plants from endosperm of walnut, Juglans regia L. cultivar ‘Manregian.’ Plant Cell Rep. 7, 301–304.
McGranahan, G.H., Leslie, C.A., Uratsu, S.L., Martin, L.A., and Dandekar, A.M. (1988) Agrobacterium mediated transformation of walnut somatic embryos and regeneration of transgenic plants. Nat. Biotechnol. 6, 800–804.
McGranahan, G.H., Leslie, C.A., Uratsu, S.L., and Dandekar, A.M. (1990) Improved efficiency of the walnut somatic embryo gene transfer system. Plant Cell Rep. 8, 512–516.
Dandekar, A.M., McGranahan, G.H., Vail, P.V., Uratsu, S.L., Leslie, C., and Tebbets, J.S. (1994) Low levels of expression of wild type Bacillus thuringiensis var. Kurstaki cryIA(c) sequences in transgenic walnut somatic embryos. Plant Sci. 96, 151–162.
Dandekar, A.M., McGranahan, G.H., Vail, P.V., Uratsu, S.L., Leslie, C.A., and Tebbets, J.S. (1998) High levels of expression of full-length cryIA(c) gene from Bacillus thuringiensis in transgenic somatic walnut embryos. Plant Sci. 131, 181–193.
Vahdati, K., McKenna, J.R., Dandekar, A.M., et al. (2002) Rooting and other characteristics of a transgenic walnut hybrid (Juglans hindsii x J. regia) rootstock expressing rolABC. J. Amer. Soc. Hort. Sci. 127, 724–728.
Escobar, M.A., Leslie, C.A., McGranahan, G.H., and Dandekar, A.M. (2002) Silencing crown gall disease in walnut (Juglans regia L.). Plant Sci. 163, 591–597.
Polito, V.S., McGranahan, G.H., Pinney, K., and Leslie, C. (1989) Origin of somatic embryos from repetitively embryogenic cultures of walnut (Juglans regia L.)—implications for Agrobacterium-mediated transformation. Plant Cell Rep. 8, 219–221.
Jefferson, R.A. (1987) Assaying chimeric genes in plants:the GUS gene fusion system. Plant Mol. Biol. Rep. 5, 387–405.
Escobar, M.A., Park, J.-I., Polito, V.S., et al. (2000) Using GFP as a scorable marker in walnut somatic embryo transformation. Annal. Botany (London) 85, 831–835.
Leslie, C., McGranahan, G., and Mendum, M.L. (1997) Genetic engineering of walnut (Juglans regia L.). In: Acta Horticulturae, Vol. 442 (Gomes Pereira, J. A., ed.), ISHS, Alcobaca, Portugal, pp. 33–41.
Bosela, M.J., Smagh, G.S., and Michler, C.H. (2004) Genetic transformation of black walnut (Juglans nigra). In: Black Walnut in a New Century: Proceedings of the 6th Walnut Council Research Symposium (Michler, C.H., ed.), North Central Research Station, Forest Service, USDA, Lafayette, Indiana, pp. 45–58.
McGranahan, G., Leslie, C.A., Dandekar, A.M., Uratsu, S.L., and Yates, I.E. (1993) Transformation of pecan and regeneration of transgenic plants. Plant Cell Rep. 12, 634–638.
Reil, W.O., Leslie, C.A., Forde, H.I., and McKenna, J.R. (1998) Propagation. In: Walnut Production Manual (Ramos, D.E., ed.), Division of Agriculture and Natural Resources, University of California, Oakland, CA, pp. 71–83.
Hood, E.A., Helmer, G.L., Fraley, R.T., and Chilton, M.D. (1986). The hypervirulence of Agrobacterium tumefaciens A281 is encoded in a region of pTiBo542 outside the T-DNA. J. Bacteriol. 168, 1291–1301.
Dandekar, A.M., Martin, L.A., and McGranahan, G.H. (1988) Genetic transformation and foreign gene expression in walnut tissue. J. Am. Soc. Hort. Sci. 113, 945–949.
Van Larebeke, N., Engler, G., Holsters, M., Van den Elsacker, Zaenen, I., Schilperoort, R.A., and Schell, J. (1974) Large plasmid in Agrobacterium tumefaciens essential for crown gall-inducing ability. Nature 252, 169–170.
McBride, K.E. and Summerfelt, K.R. (1990) Improved binary vectors for Agrobacterium-mediated plant transformation. Plant Mol. Biol. 14, 269–276.
Rodriguez, R.L. and Tait, R.C. (1983) Recombinant DNA Techniques: An Introduction. Benjamin Cummings, Menlo Park, CA.
Sambrook, J., Fritsch, E.F., and Maniatis, T. (1989) Molecular Cloning—A Laboratory Manual. Cold Spring Harbor, New York.
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Leslie, C.A., Uratsu, S.L., McGranahan, G., Dandekar, A.M. (2006). Walnut (Juglans). In: Wang, K. (eds) Agrobacterium Protocols Volume 2. Methods in Molecular Biology, vol 344. Humana Press. https://doi.org/10.1385/1-59745-131-2:297
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DOI: https://doi.org/10.1385/1-59745-131-2:297
Publisher Name: Humana Press
Print ISBN: 978-1-58829-843-0
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