We have earlier shown extensive introgression between oilseed rape (Brassica napus) and B. rapa in a weedy population using AFLP markers specific for the nuclear genomes. In order to describe the progress of this introgression, we examined 117 offspring from 12 maternal plants from the introgressed population with the same AFLPmarkers; AFLP data were supported by chromosome counting. We also analysed the offspring with a speciesspecific chloroplast marker and finally evaluated the reproductive system in selected maternal plants. Our results indicated a high outcrossing rate of the introgressed maternal plants. It seemed that B. rapa most often functioned as the maternal plant in the introgression process and that the amount of oilseed rape DNA was highly diminished in the offspring compared to their introgressed maternal plants. However, our analysis of plants from the weedy population indicated that introgression can lead to both (1) exchange of chloroplast DNA between species producing B. rapa-like plants with B. napus chloroplasts and (2) incorporation of B. napus C-genome DNA into the B. rapa genome. Therefore, we question whether it can be regarded as containment to position transgenes in the chloroplast or in specific parts of the nuclear genome of B. napus. Heredity (2003) 91, 276-283.

Lecocarpus pinnatifidus is an endemic member of the Asteraceae occurring on only one island in the Galápagos archipelago. The capitula are large with female ray florets and male disc florets. They are self-compatible but this study suggests fruit set is pollen limited. Visits from Xylocopa darwini and other larger insect pollinators are rare, and small insects seem to be the main pollinators. Small insects carry few pollen grains and most likely mediate self-pollinations. Self-compatibility and seed set after selfing are the most common reproductive strategy in the Galápagos Islands and L. pinnatifidus seemingly fits well into this group.

Transgenes may be transferred from genetically modified (GM) crops to the wider environment through crosses with compatible wild or weedy relatives. For oilseed rape (Brassica napus), we found extensive transfer of nuclear as well as plastid DNA (cpDNA) to Brassica rapa in an environment with poor weed control. Some of the plants with markers from both species were apparently introgressed beyond the stage of the BC1 generation. In conventionally managed fields with oilseed rape as crop and the wild recipient as a weed, the introgression was insignificant or not detected, so apparently the extent of gene flow from the crop depended on the agricultural management or other environmental effects. Our results also showed that oilseed rape plastids were introgressed to B. rapa under field conditions. Field and laboratory experiments revealed that fitness of interspecific F1 hybrids and backcross plants with B. rapa were variable but could be as high as and even higher than the fitness of the parental species. We present results that show the importance of genotype and environment (i.e. agronomic practice and density/proportion of plant types) in the introgression of oilseed rape genes to Brassica and Raphanus species. In the light of our findings, we discuss the perspectives of releasing GM oilseed rape.

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Denne artikel udforsker sammenhængen mellem kunst, kultur, politik og demokratiudvikling. Med udgangspunkt i en serie af kulturbegivenheder med internationale hovednavne afholdt på Det Kgl. Bibliotek bringes en hel række statements i spil, der alle kommenterer på en af vor tids største udfordringer, nemlig klimakrisen. De mange internationale profiler, som alle har optrådt på International Forfatterscene på Det Kgl. Bibliotek, strækker sig lige fra præsident Macron, antropologen Bruno Latour og den amerikanske pop-artist performer Laurie Anderson m.fl. Og de kredser alle om det samme problem: nemlig spørgsmålet om hvorfor de politiske systermer ikke reagerer meget mere drastisk på den lurende klimakatastrofe. Tesen i artiklen er, at politik, kultur og klima er mere forbundne, end man tror. Og det politiske liv og kulturlivet har mere brug for hinanden, end vi normalt regner med! Demokratiet skaber rammerne for politik og kulturlivet, og den fri debat sætter demokratiet i proces. Derfor kan de store kulturarvsformidlende institutioner gøre en forskel. For her er den fri debat og uafhængige tænkning helt central, og den skal også være urørlig. Her sættes scenen for nye ideer, ny udforskning, nye visioner og kritik af det bestående. Den internationale debat har vi brug for, for alle de største samfundsmæssige udfordringer, vi kæmper med i dag, er fælles. Konklusionen er derfor, at kulturens producenter er de kulturelle strømningers diplomater. Vi i kultursektoren må påtage os et diplomatisk ansvar for at få formidlet ideer og strømninger fra en kultur til en anden.