ISSN:
1615-6110
Schlagwort(e):
Asteraceae
;
Echinops
;
Developmental morphology
;
inflorescence and flower ontogeny
Quelle:
Springer Online Journal Archives 1860-2000
Thema:
Biologie
Notizen:
Abstract InEchinops the flowers are surrounded by several scales and initiated in an acropetal and spiral succession on a cone-like inflorescence axis (Figs. 1–6). The floral organs originate in the following sequence: petals—stamens—carpels—pappus. The petals arise from a meristematic rim and therefore are already interconnected when they arise as primordia. This sympetalous zone remains rather inconspicuous for a long period, but eventually, the elongated corolla tube is formed through intercalary growth in a ring zone. Thereby, the stamens are moved upwards and form ledges on the corolla tube (Fig. 34). In the inferior ovary the usual zones of the typical angiospermous gynoecium can be distinguished, namely a “synascidiate”, “symplicate” and “hemisymplicate” zone. The ovule is borne on carpellary tissue.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1007/BF00990465
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