Biologia plantarum 2011, 55:213-224 | DOI: 10.1007/s10535-011-0032-8

Genetic transformation of barley: limiting factors

Š. Vyroubalová1, M. Šmehilová1, P. Galuszka1, L. Ohnoutková2,*
1 Department of Biochemistry, Palacký University in Olomouc, Olomouc, Czech Republic
2 Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Olomouc, Czech Republic

This review summarizes main difficulties involved in barley (Hordeum vulgare L.) transformation. The most commonly used procedures for genetic transformation in barley are Agrobacterium tumefaciens and particle bombardment mediated methods. While different barley cultivars are used for genetic engineering with varying sensitivity, recent improvements in regeneration and transformation techniques are described and summarized. Furthermore, some of the transformation complicating factors, in particular somaclonal variation and transgene insertion sites, are discussed in more detail.

Keywords: Agrobacterium; albinism; Hordeum; particle bombardment; somaclonal variation; transgene insertion site

Received: November 23, 2009; Accepted: May 5, 2010; Published: June 1, 2011Show citation

ACS AIP APA ASA Harvard Chicago IEEE ISO690 MLA NLM Turabian Vancouver
Vyroubalová, Š., Šmehilová, M., Galuszka, P., & Ohnoutková, L. (2011). Genetic transformation of barley: limiting factors. Biologia plantarum55(2), 213-224. doi: 10.1007/s10535-011-0032-8.
Download citation

References

  1. Barakat, A., Carels, N., Bernardi, G.: The distribution of genes in the genomes of Gramineae. - Proc. nat. Acad. Sci. USA 94: 6857-6861, 1997. Go to original source...
  2. Barakat, A., Gallois, P., Raynal, M., Mestre-Ortega, D., Sallaud, C., Guiderdoni, E., Delseny, M., Bernardi, G.: The distribution of T-DNA in the genomes of transgenic Arabidopsis and rice. - FEBS Lett. 471: 161-164, 2000. Go to original source...
  3. Bartlett, J.G., Alves, S.C., Smedley, M., Snape, J.W., Harwood, W.A.: High-throughput Agrobacterium-mediated barley transformation. - Plant Methods 4: 22, 2008. Go to original source...
  4. Bartlett, J.G., Snape, J.W., Harwood, W.A.: Intron-mediated enhancement as a method for increasing transgene expression levels in barley. - Plant Biotechnol. J. 7: 856-866, 2009. Go to original source...
  5. Bregitzer, P., Campbell, R.D.: Genetic markers associated with green and albino plant regeneration from embryogenic barley callus. - Crop Sci. 41: 173-179, 2001. Go to original source...
  6. Bregitzer, P., Campbell, R.D., Wu, Y.: Plant regeneration from barley callus: effects of 2,4-dichlorophenoxyacetic acid and phenylacetic acid. - Plant Cell Tissue Organ Cult. 43: 229-235, 1995a.
  7. Bregitzer, P., Dahleen, L.S., Campbell, R.D.: Enhancement of plant regeneration from embryogenic callus of commercial barley cultivars. - Plant Cell Rep. 17: 941-945, 1998a. Go to original source...
  8. Bregitzer, P., Dahleen, L.S., Neate, S., Schwarz, P., Manoharan, M.: A single backcross effectively eliminates agronomic and quality alterations caused by somaclonal variation in transgenic barley. - Crop Sci. 48: 471-479, 2008. Go to original source...
  9. Bregitzer, P., Halbert, S.E., Lemaux, P.G.: Somaclonal variation in the progeny of transgenic barley. - Theor. appl. Genet. 96: 421-425, 1998b. Go to original source...
  10. Bregitzer, P., Poulson, M.: Agronomic performance of barley lines derived from tissue culture. - Crop Sci. 35: 1144-1148, 1995. Go to original source...
  11. Bregitzer, P., Poulson, M., Jones B.L.: Malting quality of barley lines derived from tissue culture. - Cereal Chem. 72: 433-435, 1995b.
  12. Bregitzer, P., Zhang, S., Cho, M.-J., Lemaux, P.G.: Reduced somaclonal variation in barley is associated with culturing highly differentiated, meristematic tissues. - Crop Sci. 42: 1303-1308, 2002. Go to original source...
  13. Castillo, A.M., Egana, B., Sanz, J.M., Cistué, L.: Somatic embryogenesis and plant regeneration from barley cultivars grown in Spain. - Plant Cell Rep. 17: 902-906, 1998. Go to original source...
  14. Chan, M.-T., Lee, T.-M., Chang, H.-H.: Transformation of indica rice (Oryza sativa L.) mediated by Agrobacterium tumefaciens. - Plant Cell Physiol. 33: 577-583, 1992.
  15. Chang, Y., Von Zitzewitz, J., Hayes, P.M., Chen, T.H.H.: High frequency plant regeneration from immature embryos of an elite barley cultivar (Hordeum vulgare L. cv. Morex). - Plant Cell Rep. 21: 733-738, 2003.
  16. Cheng, M., Fry, J.E., Pang, S., Zhou, H., Hironaka, C.M., Duncan, D.R., Conner, T.W., Wan, Y.: Genetic transformation of wheat mediated by Agrobacterium tumefaciens. - Plant Physiol. 115: 971-980, 1997. Go to original source...
  17. Cho, M.-J., Choi, H.-W., Buchanan, B.B., Lemaux, P.G.: Inheritance of tissue-specific expression of barley hordein promoter-uidA fusions in transgenic barley plants. - Theor. appl. Genet. 98: 1253-1262, 1999. Go to original source...
  18. Cho, M.-J., Jiang, W., Lemaux, P.G.: Transformation of recalcitrant barley cultivars through improvement of regenerability and decreased albinism. - Plant Sci. 138: 229-244, 1998. Go to original source...
  19. Choi, H.-W., Lemaux, P.G., Cho, M.-J.: Increased chromosomal variation in transgenic versus nontransgenic barley (Hordeum vulgare L.) plants. - Crop Sci. 40: 524-533, 2000a. Go to original source...
  20. Choi, H.-W., Lemaux, P.G., Cho, M.-J.: Selection and osmotic treatment exacerbate cytological aberrations in transformed barley (Hordeum vulgare). - J. Plant Physiol. 158: 935-943, 2001. Go to original source...
  21. Choi, H.-W., Lemaux, P.G., Cho, M.-J.: Use of fluorescence in situ hybridization for gross mapping of transgenes and screening for homozygous plants in transgenic barley (Hordeum vulgare L.). - Theor. appl. Genet. 106: 92-100, 2002. Go to original source...
  22. Christensen, A.H., Quail, P.H.: Ubiquitin promoter-based vectors for high-level expression of selectable and/or screenable marker genes in monocotyledonous plants. - Transgenic Res. 5: 213-218, 1996. Go to original source...
  23. Constantin, M. J.: Chromosome instability in cell and tissue cultures and regenerated plants. - Environ. exp. Bot. 21: 359-368, 1981. Go to original source...
  24. Coronado, M.-J., Hensel, G., Broeders, S., Otto, I., Kumlehn, J.: Immature pollen-derived doubled haploid formation in barley cv. Golden Promise as a tool for transgene recombination. - Acta Physiol. Plant 27: 591-599, 2005. Go to original source...
  25. Dahleen, L.S.: Improved plant regeneration from barley callus cultures by increased copper levels. - Plant Cell Tissue Organ Cult. 43: 267-269, 1995.
  26. Dahleen, L.S., Bregitzer, P.: An improved media system for high regeneration rates from barley immature embryoderived callus cultures of commercial cultivars. - Crop Sci. 42: 934-938, 2002. Go to original source...
  27. Dahleen, L.S., Manoharan, M.: Recent advances in barley transformation. - In Vitro cell. dev. Biol. Plant 43: 493-506, 2007. Go to original source...
  28. Delhaize, E., Ryan, P.R., Hebb, D.M., Yamamoto, Y., Sasaki, T., Matsumoto, H.: Engineering high-level aluminum tolerance in barley with the ALMT1 gene. - Proc. nat. Acad. Sci. USA 101: 15249-15254, 2004. Go to original source...
  29. Foroughi-Wehr, B., Friedt, W., Wenzel, G.: On the genetic improvement of androgenetic haploid formation in Hordeum vulgare L. - Theor. appl. Genet. 62: 233-239, 1982. Go to original source...
  30. Funatsuki, H., Kuroda, H., Kihara, M., Lazzeri, P.A., Müller, E., Lörz, H., Kishinami, I.: Fertile transgenic barley generated by direct DNA transfer to protoplasts. - Theor. appl. Genet. 91: 707-712, 1995. Go to original source...
  31. Godwin, I.D., Williams, S.B., Pandit, P.S., Laidlaw, H.K.C.: Multifunctional grains for the future: genetic engineering for enhanced and novel cereal quality. - In Vitro cell. dev. Biol. Plant 45: 383-399, 2009. Go to original source...
  32. Goedeke, S., Hensel, G., Kapusi, E., Gahrtz, M., Kumlehn, J.: Transgenic barley in fundamental research and biotechnology. - Transgenic Plant J. 1: 104-117, 2007.
  33. Goldstein, C.S., Kronstad, W.E.: Tissue culture and plant regeneration from immature embryo explants of barley, Hordeum vulgare. - Theor. appl. Genet. 71: 631-636, 1986. Go to original source...
  34. Grandbastien, M.A.: Activation of plant retrotransposons under stress conditions. - Trends Plant Sci. 3: 181-187, 1998. Go to original source...
  35. Hagio, T., Hirabayashi, T., Machii, H., Tomotsune, H.: Production of fertile transgenic barley (Hordeum vulgare L.) plant using the hygromycin-resistance marker. - Plant Cell Rep. 14: 329-334, 1995. Go to original source...
  36. Hansen, M., Lange, M., Friis, C., Dionisio, G., Holm, P.B., Vincze, E.: Antisense-mediated suppression of C-hordein biosynthesis in the barley grain results in correlated changes in the transcriptome, protein profile, and amino acid composition. - J. exp. Bot. 58: 3987-3995, 2007. Go to original source...
  37. He, T., Jia, J.F.: High frequency plant regeneration from mature embryo explants of highland barley (Hordeum vulgare L. var. nudum Hk. F.) under endosperm-supported culture. - Plant Cell Tissue Organ Cult. 95: 251-254, 2008. Go to original source...
  38. Hensel, G., Kastner, C., Oleszczuk, S., Riechen, J., Kumlehn, J.: Agrobacterium-mediated gene transfer to cereal crop plants: current protocols for barley, wheat, triticale, and maize. - Int. J. Plant Genomics 2009: 1-9, 2009. Go to original source...
  39. Hensel, G., Valkov, V., Middlefell-Williams, J., Kumlehn, J.: Efficient generation of transgenic barley: the way forward to modulate plant-microbe interactions. - J. Plant Physiol. 165: 71-82, 2008. Go to original source...
  40. Hiei, Y., Komari, T., Kubo, T.: Transformation of rice mediated by Agrobacterium tumefaciens. - Plant mol. Biol. 35: 205-218, 1997. Go to original source...
  41. Hiei, Y., Ohta, S., Komari, T., Kumashiro, T.: Efficient transformation of rice (Oryza sativa L.) mediated by Agrobacterium and sequence analysis of the boundaries of the T-DNA. - Plant J. 6: 271-282, 1994. Go to original source...
  42. Holm, P.B., Olsen, O., Schnorf, M., Brinch-Pedersen, H., Knudsen, S.: Transformation of barley by microinjection into isolated zygote protoplasts. - Transgenic Res. 9: 21-32, 2000. Go to original source...
  43. Holme, I.B., Brinch-Pedersen, H., Lange, M., Holm, P.B.: Transformation of different barley (Hordeum vulgare L.) cultivars by Agrobacterium tumefaciens infection of in vitro cultured ovules. - Plant Cell Rep. 27: 1833-1840, 2008.
  44. Ishida, Y., Saito, H., Ohta, S., Hiei, Y., Komari, T., Kumashiro, T.: High efficiency transformation of maize (Zea mays L.) mediated by Agrobacterium tumefaciens. - Nat. Biotechnol. 14: 745-750, 1996. Go to original source...
  45. Jähne, A., Becker, D., Brettschneider, R., Lörz, H.: Regeneration of transgenic, microspore-derived, fertile barley. - Theor. appl. Genet. 89: 525-533, 1994. Go to original source...
  46. Jha, A.K., Dahleen, L.S., Suttle, J.C.: Ethylene influences green plant regeneration from barley callus. - Plant Cell Rep. 26: 285-290, 2007. Go to original source...
  47. Jiang, W., Cho, M.-J., Lemaux, P.G.: Improved callus quality and prolonged regenerability in model and recalcitrant barley (Hordeum vulgare L.) cultivars. - Plant Biotechnol. 15: 63-69, 1998. Go to original source...
  48. Joensuu, J.J., Kotiaho, M., Teeri, T.H., Valmu, L., Nuutila, A.M., Oksman-Caldentey, K.-M., Niklander-Teeri, V.: Glycosylated F4 (K88) fimbrial adhesin FaeG expressed in barley endosperm induces ETEC-neutralizing antibodies in mice. - Transgenic Res. 15: 359-373, 2006. Go to original source...
  49. Kao, K.N., Saleem, M., Abrams, S., Pedras, M., Horn, D., Mallard, C.: Culture conditions for induction of green plants from barley microspores by anther culture methods. - Plant Cell Rep. 9: 595-601, 1991. Go to original source...
  50. Karami, O., Esna-Ashari, M., Karimi Kurdistani, G., Aghavaisi, B.: Agrobacterium-mediated genetic transformation of plants: the role of host. - Biol. Plant. 53: 201-212, 2009. Go to original source...
  51. Kasha, K.J., Ziauddin, A., Cho, U.H.: Haploids in cereal improvement: anther and microspore culture. - In: Gustafson, J.P. (ed.): Gene Manipulation in Plant Improvement II. Pp. 213-235. Plenum Press, New York 1990. Go to original source...
  52. Kihara, M., Okada, Y., Kuroda, H., Saeki, K., Yoshigi, N., Ito, K.: Improvement of β-amylase thermostability in transgenic barley seeds and transgene stability in progeny. - Mol. Breed. 6: 511-517, 2000. Go to original source...
  53. Kihara, M., Saeki, K. Ito, K.: Rapid production of fertile transgenic barley (Hordeum vulgare L.) by direct gene transfer to primary callus-derived protoplasts. - Plant Cell Rep. 17: 937-940, 1998. Go to original source...
  54. Kim, Y.-B., Garbisu, C., Pickering I.J., Prince, R.C., George, G.N., Cho, M.-J., Wong, J.H., Buchanan, B.B: Thioredoxin h overexpressed in barley seeds enhances selenite resistance and uptake during germination and early seedling development. - Planta 218: 186-191, 2003. Go to original source...
  55. Kohli, A., Gahakwa, D., Vain, P., Laurie, D.A., Christou, P.: Transgene expression in rice engineered through particle bombardment: molecular factors controlling stable expression and transgene silencing. - Planta 208: 88-97, 1999. Go to original source...
  56. Komatsuda, T., Taguchi-Shiobara, F., Oka, S., Takaiwa, F., Annaka, T., Jacobsen, H.-J.: Transfer and mapping of the shoot-differentiation locus Shd1 in barley chromosome 2. - Genome 38: 1009-1014, 1995. Go to original source...
  57. Koprek, T., Cho, M.-J., Choi, H.-W., Kim, H.K., Zhang, S., Bregitzer, P., Lemaux, P.G.: Clearing the hurdles of small grain transformation: a molecular and cytological approach. - In: Proc. 9th Australian Barley Technical Symposium. Pp. 2.3.1-2.3.8. The Regional Institute, Melbourne 1999.
  58. Koprek, T., Rangel, S., McElroy, D., Louwerse, J.D., Williams-Carrier, R.E., Lemaux, P.G.: Transposon-mediated singlecopy gene delivery leads to increased transgene expression stability in barley. - Plant Physiol. 125: 1354-1362, 2001. Go to original source...
  59. Kumlehn, J., Serazetdinova, L., Hensel, G., Becker, D., Loerz, H.: Genetic transformation of barley (Hordeum vulgare L.) via infection of androgenetic pollen cultures with Agrobacterium tumefaciens. - Plant Biotechnol. J. 4: 251-261, 2006. Go to original source...
  60. Lange, M., Vincze, E., Wieser, H., Schjoerring, J.K., Holm, P.B.: Supression of C-hordein synthesis in barley by antisense constructs results in a more balanced amino acid composition. - J. Agr. Food Chem. 55: 6074-6081, 2007. Go to original source...
  61. Larkin, P.J., Scowcroft, W.R.: Somaclonal variation - a novel source of variability from cell cultures for plant improvement. - Theor. appl. Genet. 60: 197-214, 1981. Go to original source...
  62. Li, H.-P., Huang, T., Wang, C.-X., Liao, Y.-C.: An efficient regeneration system of barley cultivars from leaf base segments. - Biol. Plant. 53: 733-736, 2009. Go to original source...
  63. Lonsdale, D.M., Moisan, L.J., Harvey, A.J.: pFC1 to pFC7: A novel family of combinatorial cloning vectors. - Plant mol. Biol. Rep. 13: 343-345, 1995. Go to original source...
  64. Mano, Y., Takahashi, H., Sato, K., Takeda, K.: Mapping genes for callus growth and shoot regeneration in barley (Hordeum vulgare L.). - Breed. Sci. 46: 137-142, 1996. Go to original source...
  65. Manoharan, M., Dahleen, L.S.: Genetic transformation of the commercial barley (Hordeum vulgare L.) cultivar Conlon by particle bombardment of callus. - Plant Cell Rep. 21: 76-80, 2002.
  66. Manoharan, M., Dahleen, L.S., Hohn, T.M., Neate, S.M., Yu, X.-H., Alexander, N.J., McCormick, S.P., Bregitzer, P., Schwarz, P.B., Horsley, R.D.: Expression of 3-OH trichothecene acetyltransferase in barley (Hordeum vulgare L.) and effects on deoxynivalenol. - Plant Sci. 171: 699-706, 2006. Go to original source...
  67. Massiah, A., Rong, H.L., Brown, S., Laurie, S.: Accelerated production and identification of fertile, homozygous transgenic wheat lines by anther culture. - Mol. Breed. 7: 163-173, 2001. Go to original source...
  68. Matthews, P.R., Wang, M.-B., Waterhouse, P.M., Thornton, S., Fieg, S.J., Gubler, F., Jacobsen, J.V.: Marker gene elimination from transgenic barley, using co-transformation with adjacent 'twin T-DNAs' on a standard Agrobacterium transformation vector. - Mol. Breed. 7: 195-202, 2001. Go to original source...
  69. Meng, L., Ziv, M., Lemaux, P.G.: Nature of stress and transgene locus influences transgene expression stability in barley. - Plant mol. Biol. 62: 15-28, 2006. Go to original source...
  70. Mouritzen, P., Holm, P.B.: Chloroplast genome breakdown in microspore cultures of barley (Hordeum vulgare L.) occurs primarily during regeneration. - J. Plant Physiol. 144: 586-593, 1994. Go to original source...
  71. Müllerová, E., Novotný, J., Vagera, J., Harwood, W.A., Ohnoutková, L.: Induction of androgenesis in transgenic barley plants. - In: Bohanec, B. (ed.): Biotechnological Approaches for Utilization of Gametic Cells. Pp. 29-32. European Communities, Luxembourg 2001.
  72. Murashige, T. and Skoog, F.: A revised medium for rapid growth and bio-assays with tobacco tissue cultures. - Physiol. Plant. 15: 473-497, 1962. Go to original source...
  73. Murray, F., Brettell, R., Matthews, P., Bishop, D., Jacobsen, J.: Comparison of Agrobacterium-mediated transformation of four barley cultivars using the GFP and GUS reporter genes. - Plant Cell Rep. 22: 397-402, 2004. Go to original source...
  74. Nuutila, A.M., Hämäläinen, J., Mannonen, L.: Optimization of media nitrogen and copper concentrations for regeneration of green plants from polyembryogenic cultures of barley (Hordeum vulgare L.). - Plant Sci. 151: 85-92, 2000. Go to original source...
  75. Nuutila, A.M., Ritala, A., Skadsen, R.W., Mannonen, L., Kauppinen, V.: Expression of fungal thermotolerant endo-1,4-β-glucanase in transgenic barley seeds during germination. - Plant mol. Biol. 41: 777-783, 1999. Go to original source...
  76. Pawlowski, W.P., Somers, D.A.: Transgene inheritance in plants genetically engineered by microprojectile bombardment. - Mol. Biotechnol. 6: 17-30, 1996. Go to original source...
  77. Potrykus, I.: Gene transfer to cereals: an assessment. - Bio/Technology 8: 535-542, 1990. Go to original source...
  78. Przetakiewicz, A., Karas, A., Orczyk, W., Nadolska-Orczyk, A.: Agrobacterium-mediated transformation of polyploid cereals. The efficiency of selection and transgene expression in wheat. - Cell. mol. Biol. Lett. 9: 903-917, 2004.
  79. Qin, G., Kang, D., Dong, Y., Shen, Y., Zhang, L., Deng, X., Zhang, Y., Li, S., Chen, N., Niu, W., Chen, C., Liu, P., Chen, H., Li, J., Ren, Y., Gu, H., Deng, X., Qu, L.-J., Chen, Z.: Obtaining and analysis of flanking sequences from TDNA transformants of Arabidopsis. - Plant Sci. 165: 941-949, 2003. Go to original source...
  80. Ritala, A., Aspegren, K., Kurtén, U., Salmenkallio-Marttila, M., Mannonen, L., Hannus, R., Kauppinen, V., Teeri, T.H., Enari, T.-M.: Fertile transgenic barley by particle bombardment of immature embryos. - Plant mol. Biol. 24: 317-325, 1994. Go to original source...
  81. Ritala, A., Marttila, S., Wilhelmson, A., Nuutila, A.M.: Inducing homozygosity in transgenic barley (Hordeum vulgare L.) by microspore culture. - Acta Physiol. Plant. 27: 601-609, 2005. Go to original source...
  82. Roitsch, T., González, M.C.: Function and regulation of plant invertases: sweet sensations. - Trends Plant Sci. 9: 606-613, 2004. Go to original source...
  83. Roussy, I., Ahlandsberg, S., Jansson, C.: Transformation and regeneration capacities for five Nordic barley elite cultivars - evaluation of tissue culture response and transient expression. - Hereditas 134: 97-101, 2001. Go to original source...
  84. Salmenkallio-Marttila, M., Aspegren, K., Akerman, S., Kurtén, U., Mannonen, L., Ritala, A., Teeri, T.H., Kauppinen, V.: Transgenic barley (Hordeum vulgare L.) by electroporation of protoplasts. - Plant Cell Rep. 15: 301-304, 1995. Go to original source...
  85. Salvo-Garrido, H., Travella, S., Bilham, L.J., Harwood, W.A., Snape J.W.: The distribution of transgene insertion sites in barley determined by physical and genetic mapping. - Genetics 167: 1371-1379, 2004. Go to original source...
  86. Schünmann, P.H.D., Coia, G., Waterhouse, P.M.: Biopharming the SimpliRed™ HIV diagnostic reagent in barley, potato and tobacco. - Mol. Breed. 9: 113-121, 2002. Go to original source...
  87. Šerhantová, V., Ehrenbergerová, J., Ohnoutková, L.: Callus induction and regeneration efficiency of spring barley cultivars registered in the Czech Republic. - Plant Soil Environ. 50: 456-462, 2004.
  88. Sha, Y., Li, S., Pei, Z., Luo, L., Tian, Y., He, C.: Generation and flanking sequence analysis of a rice T-DNA tagged population. - Theor. appl. Genet. 108: 306-314, 2004. Go to original source...
  89. Shibata, D., Liu, Y.-G.: Agrobacterium-mediated plant transformation with large DNA fragments. - Trends Plant Sci. 5: 354-357, 2000. Go to original source...
  90. Shim, Y.S., Pauls, K.P., Kasha, K.J.: Transformation of isolated barley (Hordeum vulgare L.) microspores: II. Timing of pretreatment and temperatures relative to results of bombardment. - Genome 52: 175-190, 2009. Go to original source...
  91. Shukla, V.K., Doyon, Y., Miller, J.C., DeKelver, R.C., Moehle, E.A., Worden, S.E., Mitchell, J.C., Arnold, N.L., Gopalan, S., Meng, X., Choi, V.M., Rock, J.M., Wu, Y.-Y., Katibah, G.E., Zhifang, G., McCaskill, D., Simpson, M.A., Blakeslee, B., Greenwalt, S.A., Butler, H.J., Hinkley, S.J., Zhang, L., Rebar, E.J., Gregory, P.D., Urnov, F.D.: Precise genome modification in the crop species Zea mays using zinc-finger nucleases. - Nature 459: 437-441, 2009. Go to original source...
  92. Stoger, E., Williams, S., Keen, D., Christou, P.: Molecular characteristics of transgenic wheat and the effect on transgene expression. - Transgenic Res. 7: 463-471, 1998. Go to original source...
  93. Tachibana, K., Watanabe, T., Sekizawa, Y., Takematsu, T.: Accumulation of ammonia in plants treated with bialaphos. - J. Pestic. Sci. 11: 33-37, 1986. Go to original source...
  94. Tingay, S., McElroy, D., Kalla, R., Fieg, S., Wang, M., Thornton, S., Brettell, R.: Agrobacterium tumefaciensmediated barley transformation. - Plant J. 11: 1369-1376, 1997. Go to original source...
  95. Townsend, J.A., Wright, D.A., Winfrey, R.J., Fu, F., Maeder, M.L., Joung, J.K., Voytas, D.F.: High-frequency modification of plant genes using engineered zinc-finger nucleases. - Nature 459: 442-445, 2009. Go to original source...
  96. Travella, S., Ross, S.M., Harden, J., Everett, C., Snape, J.W., Harwood, W.A.: A comparison of transgenic barley lines produced by particle bombardment and Agrobacteriummediated techniques. - Plant Cell Rep. 23: 780-789, 2005. Go to original source...
  97. Trifonova, A., Madsen, S., Olesen, A.: Agrobacterium-mediated transgene delivery and integration into barley under a range of in vitro culture conditions. - Plant Sci. 161: 871-880, 2001. Go to original source...
  98. Tull, D., Phillipson, B.A., Kramhoft, B., Knudsen, S., Olsen, O., Svensson, B.: Enhanced amylolytic activity in germinating barley through synthesis of a bacterial alpha-amylase. - J. Cereal Sci. 37: 71-80, 2003. Go to original source...
  99. Ullrich, S.E., Edmiston, J.M., Kleinhofs, A., Kudrna, D.A., Maatougui, M.E.H.: Evaluation of somaclonal variation in barley. - Cereal Res. Commun. 19: 245-260, 1991.
  100. Wan, Y., Lemaux, P.G.: Generation of large numbers of independently transformed fertile barley plants. - Plant Physiol. 104: 37-48, 1994. Go to original source...
  101. Wang, M.-B., Abbott, D.C., Upadhyaya, N.M., Jacobsen, J.V., Waterhouse, P.M.: Agrobacterium tumefaciens-mediated transformation of an elite Australian barley cultivar with virus resistance and reporter genes. - Aust. J. Plant Physiol. 28: 149-156, 2001. Go to original source...
  102. Wang, M.-B., Abbott, D.C., Waterhouse, P.M.: A single copy of a virus-derived transgene encoding hairpin RNA gives immunity to barley yellow dwarf virus. - Mol. Plant Pathol. 1: 347-356, 2000. Go to original source...
  103. Wang, X.-H., Lazzeri, P. A., Lörz, H.: Chromosomal variation in dividing protoplasts derived from cell suspensions of barley (Hordeum vulgare L.). - Theor. appl. Genet. 85: 181-185, 1992. Go to original source...
  104. Xue, G.P., Patel, M., Johnson, J.S., Smyth, D.J., Vickers, C.E.: Selectable marker-free transgenic barley producing a high level of cellulase (1,4-β-glucanase) in developing grains. - Plant Cell Rep. 21: 1088-1094, 2003. Go to original source...
  105. Zatloukal, M., Gemrotová, M., Doležal, K., Havlíček, L., SpÍchal, L., Strnad, M.: Novel potent inhibitors of A. thaliana cytokinin oxidase/dehydrogenase. - Bioorg. Med. Chem. 16: 9268-9275, 2008. Go to original source...
  106. Zhang, S., Cho, M.-J., Koprek, T., Yun, R., Bregitzer, P., Lemaux, P.G.: Genetic transformation of commercial cultivars of oat (Avena sativa L.) and barley (Hordeum vulgare L.) using in vitro shoot meristematic cultures derived from germinated seedlings. - Plant Cell Rep. 18: 959-966, 1999. Go to original source...
  107. Ziauddin, A., Kasha, K.J.: Long-term callus cultures of diploid barley (Hordeum vulgare). II. Effect of auxins on chromosomal status of cultures and regeneration of plants. - Euphytica 48: 279-286, 1990. Go to original source...