Controlled reciprocal crosses between B. rapa and F1-hybrids (B. napus (♀) ×  B. rapa), giving 20 pair-crossings, were made to reveal possible irregularities in chloroplast inheritance during production of BC1s. Despite the close relationship of chloroplasts in B. rapa and B. napus, development of PCR-based molecular markers specific to B. rapa chloroplasts and B. napus chloroplasts was successful. Offspring from each cross were investigated and among these, we found no irregular chloroplast inheritance, since their plastid genotypes in all cases were identical to that of their mother. With a certainty of 95% our data indicate that the probability that chloroplasts are being inherited paternally is less than 0.015. In oilseed rape, pollen-mediated transgene-dispersal poses a well-known risk. Our results support development of transplastomic oilseed rape as an approach to reduce transgene dispersal.

HereditasVolume 125, Issue 1 p. 89-91 Open Access Natural Hybridisation between Oilseed Rape and a Wild Relative: Hybrids among Seeds from Weedy B. Campestris Lars Landbo, Lars Landbo Aarhus University, Department of Ecology and Genetics, Ny Munkegade, Building 540, DK-8000 Aarhus, Denmark Environmenlal Science and Technology Department, Gene Technology and Population Biology, Risø National Laboratory, DK-4000 Roskilde, DenmarkSearch for more papers by this authorBente Andersen, Bente Andersen Environmenlal Science and Technology Department, Gene Technology and Population Biology, Risø National Laboratory, DK-4000 Roskilde, DenmarkSearch for more papers by this authorRikke B. Jørgensen, Rikke B. Jørgensen Environmenlal Science and Technology Department, Gene Technology and Population Biology, Risø National Laboratory, DK-4000 Roskilde, Denmark *Corresponding authorSearch for more papers by this author Lars Landbo, Lars Landbo Aarhus University, Department of Ecology and Genetics, Ny Munkegade, Building 540, DK-8000 Aarhus, Denmark Environmenlal Science and Technology Department, Gene Technology and Population Biology, Risø National Laboratory, DK-4000 Roskilde, DenmarkSearch for more papers by this authorBente Andersen, Bente Andersen Environmenlal Science and Technology Department, Gene Technology and Population Biology, Risø National Laboratory, DK-4000 Roskilde, DenmarkSearch for more papers by this authorRikke B. Jørgensen, Rikke B. Jørgensen Environmenlal Science and Technology Department, Gene Technology and Population Biology, Risø National Laboratory, DK-4000 Roskilde, Denmark *Corresponding authorSearch for more papers by this author First published: November 1996 https://doi.org/10.1111/j.1601-5223.1996.00089.xCitations: 8 AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL References Dale, P. J., 1994. The impact of hybrids between genetically modified crop plants and their related species: general considerations. Mol. Ecol. 3: 31– 36 Jørgensen, R. B. and Andersen B. 1994. Spontaneous hybridisation between oilseed rape (Brussicu nupus) and weedy B. campestris (Brassicaceae): a risk of growing genetically modified oilseed rape. Am. J. Bot. 81: 1620– 1626 Jørgensen, R. B., Andersen, B., Landbo, L. and Mikkelsen, T. R. 1996. Spontaneous hybridisation between oilseed rape (Brassica napus) and weedy relatives. Acta. Hort. 407: 193– 200 Mikkelsen, T. R., Jensen, J. and Jørgensen, R. B. 1996a. Inheritance of oilseed rape (Brassica nupus) RAPD markers in a backcross progeny with Brassica eampestris. Theor. Appl. Genet. 92: 492– 491 Mikkelsen, T. R., Andersen, B. and Jørgensen, R. B. 1996b. The risk of crop transgene spread. Nutre 380: 31 Raybould, A. F. and Gray A. J. 1993. Genetically modified crops and hybridisation with wild relatives: a UK perspective. J. Appl. Ecol. 30: 199– 219 Rogers, H. J. and Parkes, H. C. 1995. Transgenic plants and the environment. J. Exp. Bot. 46: 467– 488 Wharton, M. J. 1955. The use of the tetrazolium test for determining the viability of seeds of the genus Brussica. Pror. Int. Seed Tesr. Ass. 20: 81– 88 Citing Literature Volume125, Issue1November 1996Pages 89-91 ReferencesRelatedInformation

Wild relatives of genetically engineered crops can acquire transgenic traits such as herbicide resistance via spontaneous crop–wild hybridization. In agricultural weeds, resistance to herbicides is often a beneficial trait, but little is known about possible costs that could affect the persistence of this trait when herbicides are not used. We tested for costs associated with transgenic resistance to glufosinate when introgressed into weedy Brassica rapa. Crosses were made between transgenic B. napus and wild B. rapa from Denmark. F1 progeny were backcrossed to B. rapa and BC1 plants were selected for chromosome numbers similar to B. rapa. Further backcrossing resulted in a BC2 generation that was hemizygous for herbicide resistance. We quantified the reproductive success of 457 BC3 progeny representing six full‐sib families raised in growth rooms (plants were pollinated by captive bumblebees). Pollen fertility and seed production of BC3 plants were as great as those of B. rapa raised in the same growth rooms. Segregation for herbicide resistance in BC3 plants was 1:1 overall, but the frequency of resistant progeny was lower than expected in one family and higher than expected in another. There were no significant differences between transgenic and nontransgenic plants in survival or the number of seeds per plant, indicating that costs associated with the transgene are probably negligible. Results from this growth‐chamber study suggest that transgenic resistance to glufosinate is capable of introgressing into populations of B. rapa and persisting, even in the absence of selection due to herbicide application.

not do this risks re-swallowing noxious material.Because the stomach is always on the right, it should be no surprise that anurans always use their right hand for this 'gastric grooming'.In fact, the prolapsed stomach normally lies posterior, near the angle of the jaw, and beyond the reach of the left hand.None of our observations detracts from the conclusions of Bisazza et al., but they do suggest that in a search for the evol-utionary origin of brain lateralization in higher vertebrates, one should take into consideration natural asymmetries in viscera and visceral functions.

Frequencies of spontaneous hybridization between oilseed rape ( Brassica napus L.) and weedy Brassica campesíris ssp. campestris L. were measured in agricultural fields. Hybrids were identified by enzyme electrophoresis, random amplified polymorphic DNA (RAPD) analysis, chromosome counting, morphology, and pollen fertility. When the two species were mixed 1:1 , B. campestris produced 13% hybrid seeds and oilseed rape 9%. In two experiments with single plants of the self-incompatible B. campestris widely spaced within fields of oilseed rape, 56% and 93% hybrid seeds were produced. Analysis of a weedy population of B. campestris in oilseed rape revealed 60% hybrid seeds. Backcrossing of the hybrids to the weedy species seems to occur as supported by the finding in a natural population of two B. campestris -like plants with a marker specific to oilseed rape. The results suggest that transgenes could be dispersed from oilseed rape to B. campestris.

Barley (Hordeum vulgare L.) protoplasts isolated from four suspensions and from microspore derived proembryos improved their colony formation when supplied with conditioned medium from barley suspensions. Up to 11 % of the protoplasts formed colonies larger than 200 μm. Data were obtained on pH of the conditioning media, their protein profile on SDS-PAGE, contents of IAA and zeatin/zeatin derivatives and the growth rate of the medium producing suspensions. The effect on colony formation from treatment of the conditioned media with heat, acid or base depended on the combination of protoplasts and conditioner. Ultrafiltration showed that the molecular weight of the conditioning factors was larger than 10,000 daltons. Among the six suspensions used for conditioning, two suspensions derived from liquid cultures of protoplasts had the best conditioning ability.

Callus was induced from hybrids between cultivated barley (Hordeum vulgare L. ssp. vulgare) and ten species of wild barley (Hordeum L.) as well as from one backcross line ((H. lechleri x H. vulgare) x H. vulgare). Successful callus induction and regeneration of plants were achieved from explants of young spikes on the barley medium J 25–8. The capacity for plant regeneration was dependent on the wild parental species. In particular, combinations with four related wild species, viz. H. jubatum, H. roshevitzii, H. lechleri, and H. procerum, regenerated high numbers of plants from calli.

The extraction, reduction, and alkylation of barley hordein for routine electrophoresis in sodium dodecyl sulfate-polyacrylamide gels were studied to set up a simple preparation procedure giving well-resolved bands in the electrophoresis gel. Hordein was extracted from single crushed seeds or flour by aqueous 50% propan-2-ol containing a Tris-borate buffer, pH 8.6. The presence of the buffer facilitates the consecutive complete reduction of the extracted protein in the alcohol. Reduction and alkylation in the buffer containing propan-2-ol give sharper bands in the electrophoresis than reduction in a buffer without propan-2-ol but containing sodium dodecyl sulfate.