Problems of apomictic reproduction in the families Compositae and Rosaceae
1996
Czapik, R. (Jagellonian Univ., Krakow (Poland). Dept. of Plant Cytology and Embryology)
New methods are being elaborated and new problems solved within the following genera known to be apomictic, viz. Antennaria, Hieracium, Taraxacum, Alchemilla, Potentilla and Rubus. 7 general problems are considered in the present article: 1. frequency of apomixis; 2. occurrence of apospory and diplospory within one taxon; 3. nonfunctional apospory; 4. facultativeness of autonomous apomixis; 5. origin of endosperm; 6. timing of embryo and endosperm development in apomicts; 7. instability of the endosperm type.
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