ibclogo XVI International Botanical Congess


Abstract Number: 5521
Poster No. = 2599


APOMIXIS IN TARAXACUM OFFICINALE IS MEDIATED BY MULTIPLE GENES


Peter van Baarlen, Rolf F. Hoekstra, and J. Hans de Jong. Laboratory of Genetics, Wageningen University, Dreijenlaan 2, 6703 HA Wageningen, the Netherlands


Dandelions, Taraxacum officinale, may reproduce sexually or apomictic. Despite the differences in ploidy level, sexual (2n=2x) dandelions can be crossed with apomicts (2n=3x). We analysed meiosis using standard procedures and cytoembryological aspects using a tissue clearing method and Nomarski DIC microscopy, enabling a qualitative analysis of female meiosis and the progression through megasporogenesis, gametogenesis and embryo and endosperm development. Several hybrids were known to have low seed set or seed germination. Our study reveals that the reduction of female fertility in these hybrids results from lack of embryo sac formation or embryo or endosperm development. An accompanying poster by Van Dijk and Bakx-Schotman reports on inheritance and breakdown of apomixis in these hybrids.


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