Hostname: page-component-5f745c7db-6bmsf Total loading time: 0 Render date: 2025-01-06T11:17:27.835Z Has data issue: true hasContentIssue false
  • English
  • Français

Crop-to-wild gene flow, introgression and possible fitness effects of transgenes

Published online by Cambridge University Press:  15 January 2003

Eric Jenczewski ,
Joëlle Ronfort  and
Anne-Marie Chèvre
Eric Jenczewski
Affiliation:
Unité Mixte de Recherche ENSAR-INRA, Amélioration des plantes et biotechnologies végétales - Domaine de la Motte, BP 35327, 35653 Le Rheu Cedex, France
Joëlle Ronfort
Affiliation:
UFR-GAP INRA Montpellier, Domaine de Melgueil, 34130 Mauguio, France
Anne-Marie Chèvre
Affiliation:
Unité Mixte de Recherche ENSAR-INRA, Amélioration des plantes et biotechnologies végétales - Domaine de la Motte, BP 35327, 35653 Le Rheu Cedex, France

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Crop-to-wild gene flow has received close attention over the past ten years in connection with the development and cultivation of transgenic crops. In this paper, we review key examples of crop/wild sympatry and overlapping flowering phenology, pollen and seed dispersal, the barriers to hybridisation and introgression, the evolution and fate of interspecific hybrids, their fitness, and the potential cost of transgenes. We pay particular attention to ways in which the evolution and divergence between crops and their wild relatives may interfere with these successive steps. Our review suggests that crop-to-weed gene flow is highly idiosyncratic and that crop gene dispersion will certainly be very difficult to preclude totally. Future directions for research should thus focus on the long-term establishment and effects of transgenes on natural communities.

Keywords

gene flowhybridizationintrogressionhybrid fitnesstransgene costcrop-wild complexes
Type
Research Article
Information
Environmental Biosafety Research , Volume 2 , Issue 1 , January 2003 , pp. 9 - 24
Copyright
© ISBR, EDP Sciences, 2003

References

Arias, DM, Rieseberg, LH (1994) Gene flow between cultivated and wild sunflowers. Theor. Appl. Genet. 89: 655-660 CrossRef
Arnold ML (1997) Natural hybridization and evolution. Oxford University Press, Oxford
Arriola PE, Ellstrand NC (1996) Crop-to-weed gene flow in the genus Sorghum (Poaceae): spontaneous interspecific hybridization between johnsongrass, Sorghum halepense, and crop sorghum, S. bicolor. Am. J. Bot. 83: 1153-1160
Arriola, PE, Ellstrand, NC (1997) Fitness of interspecific hybrids in the genus Sorghum: persistence of crop genes in wild populations. Ecol. Appl. 7: 512-518 CrossRef
Baranger, A, Chèvre, AM, Eber, F, Renard, M (1995) Effect of oilseed rape genotype on the spontaneous hybridization rate with a weedy species: an assessment of transgene dispersal. Theor. Appl. Genet. 91: 956-963
Bartsch, D, Lehnen, M, Clegg, J, Pohl-Orf, M, Schuphan, I, Ellstrand, NC (1999) Impact of gene flow from cultivated beet on genetic diversity of wild sea beet populations. Mol. Ecol. 8: 1733-1741 CrossRef
Bergelson, J (1994) Changes in fecundity do not predict invasiveness: a model study of transgenic plants. Ecology 75: 249-252 CrossRef
Bing, DJ, Downey, RK, Rakow, GFM (1996) Hybridizations among Brassica napus, B. rapa and B. juncea and their weedy relatives B. nigra and Sinapis arvensis under open pollination conditions in the fields. Plant Breed. 115: 470-473 CrossRef
Boudry, P, Mörchen, M, Saumitou-Laprade, P, Vernet, P, Van Dijk, H (1993) The origin and evolution of weed beets: consequences for the breeding and release of herbicide-resistant transgenic sugar beets. Theor. Appl. Genet. 87: 471-478 CrossRef
Bretagnolle, F, Thompson, JD (1995) Gametes with the somatic chromosome number: mechanisms of their formation and role in the evolution of autopolyploid plants. New Phytol. 129: 1-22 CrossRef
Burke, JM, Voss, TJ, Arnold, ML (1998) Genetic interactions and natural selection in Louisiana iris hybrids. Evolution 52: 1304-1310 CrossRef
Chadoeuf, R, Darmency, H, Maillet, J, Renard, M (1998) Survival of buried seeds of interspecific hybrids between oilseed rape, hoary mustard and wild radish. Field Crop Res. 58: 197-204 CrossRef
Chèvre, AM, Eber, F, Baranger, A, Renard, M (1997) Gene flow from transgenic crops. Nature 389: 924 CrossRef
Chèvre, AM, Eber, F, Baranger, A, Boucherie, R, Broucqsault, LM, Bouchet, Y, Renard, M (1998a) Risks assessment on crucifer species. Acta Hort. 459: 219-224 CrossRef
Chèvre, AM, Eber, F, Baranger, A, Hureau, G, Barret, P, Picault, H, Renard, M (1998b) Characterisation of backcross generations obtained under field conditions from oilseed rape-wild radish F1 interspecific hybrids: an assessment of transgene dispersal. Theor. Appl. Genet. 97: 80-98
Chèvre, AM, Eber, F, Darmency, H, Fleury, A, Picault, H, Letanneur, JC, Renard, M (2000) Assessment of interspecific hybridization between transgenic oilseed rape and wild radish under normal agronomic conditions. Theor. Appl. Genet. 100: 1233-1239
Conner, AJ, Dale, PJ (1996) Reconsideration of pollen dispersal data from field trials of transgenic potatoes. Theor. Appl. Genet. 92: 505-508 CrossRef
Crawley, MJ, Brown, SL (1995) Seed limitation and the dynamics of feral oilseed rape on the M25 motorway. Proc. Roy. Soc. Lond. 259: 49-54 CrossRef
Crawley, MJ, Hails, RS, Rees, M, Kohn, D, Buxton, J (1993) Ecology of transgenic oilseed rape in natural habitats. Nature 363: 620-623 CrossRef
Darmency, H, Lefol, E, Fleury, A (1998) Spontaneous hybridizations between oilseed rape and wild radish. Mol. Ecol. 7: 1467-1473 CrossRef
David JL, Bousseau D, Dussautoir J-C (2000) Étude sur les possibilités d'hybridation entre les blés cultivés et quelques espèces apparentées (Aegilops spp.) en France. XIe colloque international sur la biologie des mauvaises herbes. Dijon, France, pp 6-8
De Vries FT, van der Meijden R, Brandenburg WA (1992) Botanical files: a study of the real chances for spontaneous gene flow from cultivated plants to the wild flora of the Netherlands. Gorteria suppl1, Rijksherbarium / Hortus Botanicus, Leiden
De Wet, JMJ, Harlan, JR (1975) Weeds and domesticates: Evolution in the man-made habitat. Econ. Bot. 29: 99-107 CrossRef
Delourme, R, Foisset, N, Horvais, R, Barret, P, Champagne, G, Cheung, WY, Landry, BS, Renard, M (1998) Characterisa- tion of the radish introgression carrying the Rfo restorer gene for the Ogu-INRA cytoplasmic male sterility in rapeseed (Brassica napus L.). Theor. Appl. Genet. 97: 129-134 CrossRef
Doebley, JF (1990) Molecular evidence for gene flow among Zea species. Bioscience 40: 443-448 CrossRef
Dvorak, J (1972) Genetic variability in Aegilops speltoides affecting homoelogous pairing in wheat. Can. J. Genet. Cytol. 14: 371-380 CrossRef
Eber, F, Chèvre, AM, Baranger, A, Vallée, P, Tanguy, X, Renard, M (1994) Spontaneous hybridization between a male-sterile oilseed rape and two weeds. Theor. Appl. Genet. 88: 362-368
Eber, F, Boucherie, R, Broucqsault, LM, Bouchet, Y, Chèvre, AM (1998) Spontaneous hybridization between vegetable crops and weeds 1. Garden radish (Raphanus sativus L.) and wild mustard (Sinapis arvensis L.). Agronomie 18: 489-497 CrossRef
Ellstrand NC (1992) Gene flow by pollen; implications for plant conservation genetics. Oikos 63: 77-86
Ellstrand, NC (2001) When transgenes wander, should we worry? Plant Physiol. 125: 1543-1545 CrossRef
Ellstrand, NC, Hoffman, CA (1990) Hybridization as an avenue of escape for engineered genes. Bioscience 40: 438-442 CrossRef
Ellstrand, NC, Schierenbelk, KA (2000) Hybridization: a stimulus for the evolution of invasiveness in plants? Proc. Natl. Acad. Sci. USA 97: 7043-7050 CrossRef
Ellstrand, NC, Devlin, D, Marshall, DL (1989) Gene flow by pollen into small populations: Data from experimental and natural stands of wild radish. Proc. Natl. Acad. Sci. USA 86: 9044-9047 CrossRef
Ellstrand, NC, Prentice, HC, Hancock, JF (1999) Gene flow and introgression from domesticated plants into their wild relatives. Ann. Rev. Ecol. Syst. 30: 539-563 CrossRef
Evans, MMS, Kermicle, JL (2001) Teosinte crossing barrier1, a locus governing hybridisation of teosinte with maize. Theor. Appl. Genet. 103: 259-265 CrossRef
Frankel OM, Brown AHD, Burdon JJ (1995) The conservation of plant biodiversity. Cambridge University Press, Cambridge, 299 p
Gallais A, Bannerot H (1992) Amélioration des espèces végétales cultivées. Objectifs et critères de sélection. INRA Éditions, Paris
Gauthier FM, McGinnis RC (1968) The meiotic behaviour of a nulli-haploid plant in Avena sativa. Can. J. Genet. Cytol. 10: 186-189
Giddings, GD, Sackville Hamilton, NR, Hayward, MD (1997a) The release of genetically modified grasses. Part 1: pollen dispersal to traps in Lolium perenne. Theor. Appl. Genet. 94: 1000-1006 CrossRef
Giddings, GD, Sackville Hamilton, NR, Hayward, MD (1997b) The release of genetically modified grasses. Part 2: the influence of wind direction on pollen dispersal. Theor. Appl. Genet. 94: 1007-1014 CrossRef
Gliddon, C (1994) The impact of hybrids between genetically modified crop plants and their related species: biological models and theoretical perspectives. Mol. Ecol. 3: 41-44 CrossRef
Guéritaine, G, Sester, M, Eber, F, Chèvre, AM, Darmency, H (2002) Fitness components of progeny of hybrids between transgenic oilseed rape (Brassica napus) and wild radish (Raphanus raphanistrum). Mol. Ecol. 11: 1419-1426 CrossRef
Hails, RS, Rees, M, Kohn, DD, Crawley, MJ (1997) Burial and seed survival in Brassica napus subsp. oleifera and Sinapis arvensis including a comparison of transgenic and non-transgenic lines of the crop. Proc. Roy. Soc. Lond. 264: 1-7 CrossRef
Haldane, JBS (1930) A mathematical theory of natural and artificial selection. Part, IV: Isolation. Proc. Cambridge Philos. Soc. 26: 20-30 CrossRef
Harlan JR (1992) Crops and Man. American society of Agronomy, Madison
Harrison RG (1990) Hybrid zones: windows on evolutionary process. Oxford surveys in Evolutionary Biology, Oxford University Press, Oxford, pp 69-128
Hauser TP, Jorgensen RB, Ostergard H (1997) Preferential exclusion of hybrids in mixed pollinations between oilseed rape (Brassica napus) and weedy B. campestris. Am. J. Bot. 84: 756-762
Hauser, TP, Shaw, RG, Ostergard, H (1998a) Fitness of F1 hybrids between weedy Brassica rapa and oilseed rape (B. napus). Heredity 81: 429-435 CrossRef
Hauser, TP, Jorgensen, RB, Ostergard, H (1998b) Fitness of backcross and F2 hybrids between weedy Brassica rapa and oilseed rape (B. napus). Heredity 81: 436-443 CrossRef
Hodges, SA, Burke, JM, Arnold, ML (1996) Natural formation of iris hybrids: experimental evidence on the establishment of hybrid zones. Evolution 50: 2504-2509 CrossRef
Jauhar PP (1993) Cytogenetics of the Festuca-Lolium complex. Relevance to plant breeding. Monographs on Theoretical and Applied Genetics 18, Springer-Verlag, Heidelberg
Jenczewski, E, Prosperi, JM, Ronfort, J (1999) Evidence for gene flow between wild and cultivated Medicago sativa (Leguminosae) based on allozyme and quantitative traits. Am. J. Bot. 86: 677-687 CrossRef
Johnston, SA, den Nijs, TPM, Peloquin, SJ, Hanneman, RE Jr (1980) The significance of genic balance to endosperm development in interspecific crosses. Theor. Appl. Genet. 57: 5-9 CrossRef
Jorgensen, RB, Andersen, B (1994) Spontaneous hybridiza- tion between oilseed rape (Brassica napus) and weedy B. campestris (Brassicaceae): a risk of growing genetically modified oilseed rape. Am. J. Bot. 81: 1620-1626 CrossRef
Kareiva, PM, Morris, W, Jacobi, CM (1994) Studying and managing the risk of cross-fertilization between transgenic crops and their wild relatives. Mol. Ecol. 3: 15-21 CrossRef
Kerlan, MC, Chèvre, AM, Eber, F, Baranger, A, Renard, M (1992) Risk assessment of outcrossing of transgenic rapeseed to related species: I. Interspecific hybrid production under optimal conditions with emphasis on pollination and fertilization. Euphytica 62: 145-153 CrossRef
Kim, SC, Rieseberg, LH (1999) Genetic architecture of species differences in annual sunflowers: Implications for adaptive trait introgression. Genetics 153: 965-977
Kirkpatrick KJ, Wilson HD (1988) Interspecific gene flow in Curcubita: C. texana vs. C. pepo. Am. J. Bot. 75: 519-527
Klinger T, Ellstrand NC (1994) Engineered genes in wild populations: fitness of weed-crop hybrids of Raphanus sativus. Ecol. Appl. 41: 117-120
Klinger, T, Arriola, PE, Ellstrand, NC (1992) Crop-weed hybridization in radish (Raphanus sativus): effects of distance and population size. Am. J. Bot. 79: 1431-1435 CrossRef
Langevin, SA, Clay, K, Grace, JB (1990) The incidence and effects of hybridization between cultivated rice and its related weed red rice (Oryza sativa L.). Evolution 44: 1000-1008 CrossRef
Lavigne, C, Godelle, B, Reboud, X, Gouyon, PH (1998) A method to determine the mean pollen dispersal of individual plants growing within a large pollen source. Theor. Appl. Genet. 93: 1319-1326 CrossRef
Lewis, J (1973) Longevity of crop and weed seeds: survival after 20 years in soil. Weed Res. 13: 179-191 CrossRef
Li, Z, Pinson, SRM, Paterson, AH, Park, WD, Stansel, JW (1997) Genetics of hybrid sterility and hybrid breakdown in an intersubspecific rice (Oryza sativa L.) population. Genetics 145: 1139-1148 PubMed
Linder, CR, Schmitt, J (1994) Assessing the risks of transgene escape through time and crop-wild hybrid persistence. Mol. Ecol. 3: 23-30 CrossRef
Linder, CR, Schmitt, J (1995) Potential persistence of escaped transgenes: performance of transgenic oil-modified Brassica seeds and seedlings. Ecol. Appl. 5: 1056-1068 CrossRef
Linder, CR, Taha, I, Seiler, GJ, Snow, AA, Rieseberg, LH (1998) Long-term introgression of crop genes into wild sunflower populations. Theor. Appl. Genet. 96: 339-347 CrossRef
Luby, JJ, McNicol, RJ (1995) Gene flow from cultivated to wild raspberries in Scotland: developing a basis for risk assessment for testing and deployment to transgenic cultivars. Theor. Appl. Genet. 90: 1133-1137 CrossRef
Lukaszewski, AJ (1995) Physical distribution of translocation breakpoints in homeologous recombinants induced by the absence of the Ph1 gene in wheat and triticale. Theor. Appl. Genet. 90: 714-719 CrossRef
Manasse, RS (1992) Ecological risks of transgenic plants: effects of spatial dispersion on gene flow. Ecol. Appl. 2: 431-438 CrossRef
McPartlan, HC, Dale, PJ (1994) An assessment of gene transfer by pollen from field-grown transgenic potatoes to non-transgenic potatoes and related species. Transgenic Res. 3: 216-225 CrossRef
Metz, PL, Jacobsen, E, Nap, JP, Pereira, A, Stiekema, WJ (1997) The impact on biosafety of the phosphinothricin- tolerance transgene in interspecific B. rapa × B. napus hybrids and their successive backcrosses. Theor. Appl. Genet. 95: 442-450 CrossRef
Mikkelsen, TR, Andersen, B, Jorgensen, RB (1996) The risk of crop transgene spread. Nature 380: 31 CrossRef
Moore, G, Aragon-Alcaide, L, Roberts, M, Reader, S, Miller, T, Foote, T (1997) Are rice chromosomes components of a holocentric chromosome ancestor? Plant Mol. Biol. 35: 17-23 CrossRef
Morris, WF, Karieva, PM, Raymer, PL (1994) Do barren zones and pollen traps reduce gene escape from transgenic crops? Ecol. Appl. 4: 157-165 CrossRef
Panetsos, CA, Baker, H (1967) The origin of variation in "wild'' Raphanus sativus in California. Genetica 38: 243-274 CrossRef
Pascher, K, Gollmann, G (1997) Ecological risk assessment of transgenic plant releases: an austrian perspective. Biodiv. Conser. 8: 1139-1158 CrossRef
Paterson AH, Schertz KF, Lin Y, Lui S, Chang Y (1995) The weediness of wild plants: molecular analysis of genes influencing dispersal and persistence of Johnsongrass; Sorghum halepense (L.) Pers. Proc. Natl. Acad. Sci. USA 92: 1686-1691
Pessel, FD, Lecomte, J, Emeriau, V, Krouti, M, Messean, A, Gouyon, PH (2001) Persistence of oilseed rape (Brassica napus L.) outside of cultivated fields. Theor. Appl. Genet. 102: 841-846 CrossRef
Poncet, V, Lamy, F, Devos, KM, Gale, MD, Sarr, A, Robert, T (2000) Genetic control of domestication traits in pearl millet (Pennisetum glaucum L., Poaceae). Theor. Appl. Genet. 100: 147-159 CrossRef
Poppy, GM (2000) GM crops: environmental risks and non- target effects. Trends Plant Sci. 5: 4-6 CrossRef
Price, JS, Hobson, RN, Neale, MA, Bruce, DM (1996) Seed losses in commercial harvesting of oilseed rape. J. Agric. Engineer. Res. 65: 183-191 CrossRef
Purrington, CB, Bergelson, J (1997) Fitness consequences of genetically engineered herbicide and antibiotic resistance in Arabidopsis thaliana. Genetics 145: 807-814
Ramsey, J, Schemske, DW (1998) Pathways, mechanisms, and rates of polyploid formation in flowering plants. Ann. Rev. Ecol. Syst. 29: 467-501 CrossRef
Raybould, AF, Gray, AJ (1993) Genetically modified crops and hybridization with wild relatives: a UK perspective. J. Appl. Ecol. 30: 199-219 CrossRef
Reboud, X, Till-Bottraud, I (1991) The cost of herbicide resistance measured by a competition experiment. Theor. Appl. Genet. 82: 690-696 CrossRef
Regal, PJ (1994) Scientific principles for ecologically based risk assessment of transgenic organisms. Mol. Ecol. 3: 5-13 CrossRef
Renno, JF, Winkel, T (1996) Phenology and reproductive effort of cultivated and wild forms of Pennisetum glaucum under experimental conditions in the Sahel: implications for the maintenance of polymorphism in the species. Can. J. Bot. 74: 959-964 CrossRef
Rieger, MA, Potter, TD, Preston, C, Powles, SB (2001) Hybridisation between Brassica napus L. and Raphanus raphanistrum L. under agronomic field conditions. Theor. Appl. Genet. 103: 555-560 CrossRef
Rieseberg, LH (1997) Hybrid origins of plant species. Ann. Rev. Ecol. Syst. 28: 359-389 CrossRef
Rieseberg, LH, Carney, SE (1998) Plant hybridization. New Phytol. 140: 599-624 CrossRef
Rieseberg LH, Wendel JF (1993) Introgression and its consequences in plants. In Harrison RG, ed, Hybrid Zones and the Evolutionary Process. Oxford University Press, Oxford, pp 70-109
Rieseberg, LH, Desrochers, AM, Youn, SJ (1995) Interspecific pollen competition as a reproductive barrier between sympatric species of Helianthus (Asteraceae). Am. J. Bot. 82: 515-519 CrossRef
Rieseberg, LH, Arias, DM, Ungerer, MC, Linder, CR, Sinervo, B (1996a) The effects of mating design on introgression between chromosomally divergent sunflower species. Theor. Appl. Genet. 93: 633-644 CrossRef
Rieseberg, LH, Linder, CR, Seiler, GJ, Ungerer, MC, Arias, DM (1996b) Role of gene interactions in hybrid speciation: Evidence from ancient and experimental hybrids. Science 272: 741-745 CrossRef
Rieseberg, LH, Whitton, J, Gardner, K (1999) Hybrid zone and the genetic architecture of a barrier to gene flow between two sunflower species. Genetics 152: 713-727
Riley R (1963) The genetic regulation of meiotic behaviour in wheat and its relatives. Hereditas suppl. 2: 395-408
Robert, T, Lespinasse, R, Pernès, J, Sarr, A (1991) Gametophytic competition as influencing gene flow between wild and cultivated forms of pearl millet (Pennisetum typhoides). Genome 34: 195-200 CrossRefPubMed
Rognli, OA, Nilsson, NO, Nurminiemi, M (2000) Effects of distance and pollen competition on gene flow in the wind- pollinated grass Festuca pratensis Huds. Heredity 85: 550-560 CrossRef
Sacks, EJ, Gerhardt, LM, Graham, EB, Jacobs, J, Thorrup, TA, St Clair, DA (1997) Variation among 41 genotypes of tomato (Lycopersicum esculentum Mill) for crossability to L. peruvianum (L.) Mill. Ann. Bot. 80: 469-477 CrossRef
Santoni, S, Bervillé, A (1992) Evidences for gene exchanges between sugar beet (Beta vulgaris L.) and wild beets: consequence for transgenic sugar beets. Plant Mol. Biol. 20: 575-580 CrossRef
Scheffler, JA, Parkinson, R, Dale, PJ (1993) Frequency and distance of pollen dispersal from transgenic oilseed rape (Brassica napus). Transgenic Res. 2: 356-364 CrossRef
Scott, SE, Wilkinson, MJ (1998) Transgene risk is low. Nature 393: 320 CrossRef
Seefeldt, SS, Zemettra, RS, Young, FL, Jones, SS (1998) Production of herbicide-resistant jointed goatgrass (Aegilops cylindrica) × wheat (Triticum aestivum) hybrids in the field by natural hybridization. Weed Sci. 46: 632-634
Simmonds NW (1995) Evolution of crop plants. Longman Scientific and Technical, New York
Skogsmyr, I (1994) Gene dispersal from transgenic potatoes to co-specifics: a field trial. Theor. Appl. Genet. 88: 770-774 CrossRef
Small E (1984) Hybridization in the domesticated weed-wild complex. In Grant WF, ed, Plant Biosystematics. Academic Press, Toronto, pp 195-210
Snow, AA, Morán Palma, PM (1997) Commercialization of transgenic plants: potential ecological risks. Bioscience 47: 86-96 CrossRef
Snow, AA, Morán Palma, P, Rieseberg, LH, Wszelaki, A, Seiler, GJ (1998) Fecundity, phenology, and seed dormancy of F1 wild-crop hybrids in sunflower (Helianthus annuus, Asteraceae). Am. J. Bot. 85: 794-801 CrossRef
Snow AA, Andersen B, Jorgensen RB (1999) Costs of transgenic herbicide resistance introgressed from Brassica napus into weedy B. rapa. Mol. Ecol. 8: 605-615
Snow, AA, Uthus, KL, Culley, TM (2001) Fitness of hybrids between weedy and cultivated radish: implications for weed evolution. Ecol. Appl. 11: 934-943 CrossRef
Spencer, LJ, Snow, AA (2001) Fecundity of transgenic wild- crop hybrids of Curcubita pepo (Cucurbitaceae): implications for crop-to-wild gene flow. Heredity 86: 694-702 CrossRef
St. Amand, PC, Skenner, DZ, Peaden, RN (2000) Risk of alfalfa transgene dissemination and scale-dependent effects. Theor. Appl. Genet. 101: 107-114 CrossRef
Stewart, CN, All, JNJ, Raymer, PL, Ramachandran, S (1997) Increased fitness of transgenic insecticidal rapeseed under insect selection pressure. Mol. Ecol. 6: 773-779 CrossRef
Taylor, IB, Evans, GM (1977) The genotypic control of homoeologous chromosome associations in Lolium temulentum × Lolium perenne interspecific hybrids. Chromosoma 62: 57-67 CrossRef
Tiedje, JM, Colwell, RK, Grossman, YL, Hodson, RE, Lenski, RE, Mack, RN, Regal, PJ (1989) The planned introduction of genetically engineered organisms: ecological considerations and recommendations. Ecology 70: 298-315 CrossRef
Till-Bottraud, I, Reboud, X, Brabant, P, Lefranc, M, Rherissi, B, Vedel, F, Darmency, H (1992) Outcrossing and hybridiza- tion in wild and cultivated foxtail millets: consequences for the release of transgenic plants. Theor. Appl. Genet. 83: 940-946 CrossRef
Tomiuk, J, Hauser, TP, Bagger-Jorgensen, R (2000) A- or C- chromosomes, does it matter for the transfer of transgenes from Brassica napus? Theor. Appl. Genet. 100: 750-754 CrossRef
Truco, MJ, Hu, J, Sadowski, J, Quiros, C (1996) Inter- and intra-genomic homology of the Brassica genomes: implications for their origin and evolution. Theor. Appl. Genet. 93: 1225-1233 CrossRef
Tynan, JL, Williams, MK, Conner, AJ (1990) Low frequency of pollen dispersal from a field trial of transgenic potatoes. J. Genet. Breed. 44: 303-306
van Raamsdonk, LWD (1995) The cytological and genetical mechanism of plant domestication exemplified by four crop models. Bot. Rev. 61: 367-399 CrossRef
White, S, Doebley, J (1998) Of genes and genomes and the origin of maize. Trends Genet. 14: 327-332 CrossRef
Whitton, J, Wolf, DE, Arias, DM, Snow, AA, Rieseberg, LH (1997) The persistence of cultivar alleles in wild populations of sunflowers five generations after hybridisation. Theor. Appl. Genet. 95: 33-40 CrossRef
Wilkinson, MJ, Davenport, IJ, Charters, YM, Jones, AE, Allainguillaume, J, Butler, HT, Mason, DC, Raybould, AF (2000) A direct regional scale estimate of transgene movement from genetically modified oilseed rape to its wild progenitors. Mol. Ecol. 9: 983-991 CrossRef
Wilson, HD (1990) Gene flow in squash species. Bioscience 40: 449-455 CrossRef
Wilson, H, Manhart, J (1993) Crop/Weed gene flow: Chenopodium quinoa Willd and C. berlandieri Moq. Theor. Appl. Genet. 86: 642-648 CrossRef
Zemettra, RS, Hansen, J, Mallory-Smith, CA (1998) Potential for gene transfer between wheat (Triticum aestivum) and jointed goatgrass (Aegilops cylindrica). Weed Sci. 46: 313-317