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Embryological analysis of Hieracium pilosell from Poland

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Pogan E., Wcislo H.

Acta Biologica Cracoviensia. Series Botanica

1995

tom 37

The collective species Hieracium pilosella L. is represented in Poland by two cytotypes: the tetraploid (2n = 36) and pentaploid (2n = 45). A comparative embryological analysis of these two cytotypes showed, that tetraploid cytotype has a normal sporogenesis and sexual mode of reproduction. In the pentaploid cytotype the florets of unopened capitula were examined. Sporogenesis both in anthers and in ovules is highly disturbed. In rare cases the meiotic fully organized embryo sacs were formed. As a rule aposporic embryo sacs arising from somatic cells of chalaza or from nucellar epidermis were present. In still unopened capitula the development of embryos arising parthenogenetically preceded that of endosperm formed in the autonomous way. The occurrence of developmental abnormalities (multiply embryo sacs, polyembryony, adventitious integumental embryony) have been observed in ovules of the pentaploid cytotype.

Ograniczanie wyników

1 Acta Biologica Cracoviensia. Series Botanica

1 Pogan E.

1 Wcislo H.

1 1995

Wyniki wyszukiwania

Embryological analysis of Hieracium pilosell from Poland