Hostname: page-component-848d4c4894-tn8tq Total loading time: 0 Render date: 2024-06-27T16:00:06.608Z Has data issue: false hasContentIssue false

Gene flow hampered by low seed size of hybrids between oilseed rape and five wild relatives

Published online by Cambridge University Press:  01 June 2008

Wei Wei
Affiliation:
National Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Science, 20 Nanxincun, Beijing 100093, China
Henri Darmency*
Affiliation:
Unité Mixte de Recherche sur la Biologie et la Gestion des Adventices, Institut National de la Recherche Agronomique, INRA, 17 rue Sully, Dijon BP 86510, 21065, France
*
*Correspondence darmency@dijon.inra.fr

Abstract

Recent concern about gene flow from transgenic plants to weedy species has attracted much research on the fitness of their hybrids. However, no studies have been reported on the very early effects of the seed size of hybrids compared with parental plants for germination, seedling establishment and plant growth. We produced hybrids between male sterile Brassica napus L. (oilseed rape) and five weedy relatives, including Brassica juncea (L.) Czern, B. nigra (L.) Koch, B. rapa L., Hirschfeldia incana (L.) Lagrèze-Fossat and Raphanus raphanistrum L. The hybrid seeds formed between B. napus and B. rapa varied in size, while all the hybrid seeds formed with the other species were small. In a direct-seeded field experiment, small seeds of both parents and hybrids had a lower frequency of emergence and a lower seedling survival rate than large seeds, and resulted in later flowering with less biomass. However, no difference was recorded in a transplant experiment, indicating that growth in the juvenile period was sensitive to the small seed class in field conditions only. The optimum environmental conditions in the greenhouse probably homogenized the developmental differences observed at the early stage, and thus reduced the variation during subsequent growth in the field. This point has not been, but should be, considered in risk assessment of transgenic plants. The lower seedling establishment of small-seeded hybrids could hamper further gene flow.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2008

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Ahmed, S.U. and Zuberi, M.I. (1973) Effects of seed size on yield and some of its components in rape seed, Brassica campestris L. var. Toria. Crop Science 13, 119120.CrossRefGoogle Scholar
Akinerdem, F. (1991) Determination of the ploidy level of pure and mixed plant populations of sugar beet (Beta vulgaris L.) by flow cytometry. Plant Breeding 107, 333337.CrossRefGoogle Scholar
Allainguillaume, J., Alexander, M., Bullock, J.M., Saunders, M., Allender, C.J., King, G., Ford, C.S. and Wilkinson, M.J. (2006) Fitness of hybrids between rapeseed (Brassica napus) and wild Brassica rapa in natural habitats. Molecular Ecology 15, 11751184.CrossRefGoogle ScholarPubMed
Ammitzbøll, H., Mikkelsen, T.N. and Jørgensen, R.B. (2005) Transgene expression and fitness of hybrids between GM oilseed rape and Brassica rapa. Environmental Biosafety Research 4, 312.Google Scholar
Bing, D.J., Downey, R.K. and Rakow, G.F.W. (1996) Hybridizations among Brassica napus, B. rapa and B. juncea and their two weedy relatives B. nigra and Sinapis arvensis under open pollination conditions in the field. Plant Breeding 115, 470473.CrossRefGoogle Scholar
Chadoeuf, R., Darmency, H., Maillet, J. and Renard, M. (1998) Survival of buried seeds of interspecific hybrids between oilseed rape, hoary mustard and wild radish. Field Crops Research 58, 197204.CrossRefGoogle Scholar
Chèvre, A.M., Eber, F., Darmency, H., Fleury, A., Picault, H., Letanneur, J.C. and Renard, M. (2000) Assessment of interspecific hybridization between transgenic oilseed rape and wild radish under normal agronomic conditions. Theoretical and Applied Genetics 100, 12331239.CrossRefGoogle Scholar
Darmency, H. (1994) The impact of hybrids between genetically modified crop plants and their related species: introgression and weediness. Molecular Ecology 3, 3740.Google Scholar
Darmency, H. and Fleury, A. (2000) Mating system in Hirschfeldia incana and hybridization to oilseed rape. Weed Research 40, 231238.CrossRefGoogle Scholar
Darmency, H., Lefol, E. and Fleury, A. (1998) Spontaneous hybridizations between oilseed rape and wild radish. Molecular Ecology 7, 14671473.CrossRefGoogle Scholar
Eber, F., Chèvre, A.M., Baranger, A., Vallée, P., Tanguy, X. and Renard, M. (1994) Spontaneous hybridization between a male-sterile oilseed rape and two weeds. Theoretical and Applied Genetics 88, 362368.CrossRefGoogle ScholarPubMed
Ellstrand, N.C. (2003) Dangerous liaisons? When cultivated plants mate with their wild relatives. Baltimore, Johns Hopkins University Press.Google Scholar
Ghersa, C.M. and Martinez-Ghersa, M.A. (2000) Ecological correlates of weed seed size and persistence in the soil under different tilling systems: implications for weed management. Field Crops Research 67, 141148.Google Scholar
Guéritaine, G., Sester, M., Eber, F., Chèvre, A.M. and Darmency, H. (2002) Fitness of backcross six of hybrids between transgenic oilseed rape (Brassica napus) and wild radish (Raphanus raphanistrum). Molecular Ecology 11, 14191426.Google Scholar
Guéritaine, G., Bazot, S. and Darmency, H. (2003) Emergence and growth of hybrids between Brassica napus and Raphanus raphanistrum. New Phytologist 158, 561567.CrossRefGoogle ScholarPubMed
Håkansson, A. (1956) Seed development of Brassica oleracea and B. rapa after certain reciprocal pollinations. Hereditas 42, 373396.CrossRefGoogle Scholar
Halfhill, M.D., Sutherland, J.P., Moon, H.S., Poppy, G.M., Warwick, S.I., Weissinger, A.K., Rufty, T.W., Raymer, P.L. and Stewart, C.N. (2005) Growth, productivity, and competitiveness of introgressed weedy Brassica rapa hybrids selected for the presence of Bt cry1Ac and gfp transgenes. Molecular Ecology 14, 31773189.CrossRefGoogle ScholarPubMed
Hansen, L.B., Siegismund, H.R. and Jørgensen, R.B. (2001) Introgression between oilseed rape (Brassica napus L.) and its weedy relative B. rapa L. in a natural population. Genetic Resources and Crop Evolution 48, 621627.CrossRefGoogle Scholar
Harper, J.L. (1977) Population biology of plants. London, Academic Press.Google Scholar
Hauser, T.P., Damgaard, C. and Jørgensen, R.B. (2003) Frequency-dependent fitness of hybrids between oilseed rape (Brassica napus) and weedy B. rapa (Brassicaceae). American Journal of Botany 90, 571578.CrossRefGoogle ScholarPubMed
Heyn, F.W. (1977) Analysis of unreduced gametes in the Brassiceae by crosses between species and ploidy levels. Zeitschrift für Planzenzüchuntg 78, 1330.Google Scholar
Howard, J.W. (1939) The size of seeds in diploid and autotetraploid Brassica oleracea L. Journal of Genetics 38, 325339.CrossRefGoogle Scholar
Issaka Magha, M., Guerche, P., Bregeon, M. and Renard, M. (1993) Characterization of a spontaneous rapeseed mutant tolerant to sulfonylurea and imidazolinone herbicides. Plant Breeding 111, 132141.CrossRefGoogle Scholar
Johannessen, M.M., Andersen, B.A. and Jørgensen, R.B. (2006) Competition affects gene flow from oilseed rape (♀) to Brassica rapa (♂). Heredity 96, 360367.CrossRefGoogle ScholarPubMed
Jørgensen, R.B. and Andersen, B. (1994) Spontaneous hybridization between oilseed rape (Brassica napus) and weedy B. campestris (Brassicaceae): a risk of growing genetically modified oilseed rape. American Journal of Botany 81, 16201626.CrossRefGoogle Scholar
Kumar, A., Tomer, R.P.S., Kumar, R. and Chaudhary, R.S. (2005) Seed size studies in relation to yield attributing parameters in Indian mustard [Brassica juncea (L.) Czern and Coss]. Seed Research 33, 5456.Google Scholar
Lefol, E., Danielou, V., Darmency, H., Boucher, F., Maillet, J. and Renard, M. (1995) Gene dispersal from transgenic crops. I. Growth of interspecific hybrids between oilseed rape and the wild hoary mustard. Journal of Applied Ecology 32, 803808.CrossRefGoogle Scholar
Linder, C.R. and Schmitt, J. (1995) Potential persistence of escaped transgenes: performance of transgenic, oil-modified Brassica seeds and seedlings. Ecological Applications 5, 10561068.CrossRefGoogle Scholar
Major, D.J. (1977) Influence of seed size on yield and yield components of rape. Agronomy Journal 69, 541543.CrossRefGoogle Scholar
Moles, A.T. and Westoby, M. (2004) Seedling survival and seed size: a synthesis of the literature. Journal of Ecology 92, 372383.CrossRefGoogle Scholar
Stace, C.A. (1975) Hybridization and the flora of the British Isles. London, Academic Press.Google Scholar
Stanton, M.L. (1984) Seed variation in wild radish: effect of seed size on components of seedling and adult fitness. Ecology 65, 11051112.CrossRefGoogle Scholar
Truco, M.J., Hu, J., Sadowski, J. and Quiros, C.F. (1996) Inter- and intra-genomic homology of the Brassica genomes: implications for their origin and evolution. Theoretical and Applied Genetics 93, 12251233.CrossRefGoogle ScholarPubMed
Verdu, M. and Traveset, A. (2005) Early emergence enhances plant fitness: a phylogenetically controlled meta-analysis. Ecology 86, 13851394.CrossRefGoogle Scholar
Warwick, S.I., Légère, A., Simard, M.J. and James, T. (2008) Do escaped transgenes persist in nature? The case of an herbicide resistance transgene in a weedy Brassica rapa population. Molecular Ecology 17, 13871395.CrossRefGoogle Scholar
Westoby, M., Falster, D.S., Moles, A.T., Vesk, P.A. and Wright, I.J. (2002) Plant ecological strategies: some leading dimensions of variation between species. Annual Review of Ecology and Systematics 33, 125159.CrossRefGoogle Scholar