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Contributions to the pollen morphology of the family compositae

The pollen morphology of 24 species of Compositae belonging to 18 genera was examined by light and scanning microscopy. The present data confirms the eurypalynous nature of the family. Delimitation of the genera on the basis of pollen characters is less marked. Pollen grains usually radially symmetrical, isopolar rarely apolar, tricolporate, often porate. | Tr. J. of Biology 23 (1999) 523–535 © TÜBİTAK Contributions to the Pollen morphology of the family Compositae Anjum PERVEEN Department of Botany, University of Karachi, Karachi-PAKİSTAN Received: 01.09.1997 Abstract: The pollen morphology of 24 species of Compositae belonging to 18 genera was examined by light and scanning microscopy. The present data confirms the eurypalynous nature of the family. Delimitation of the genera on the basis of pollen characters is less marked. Pollen grains usually radially symmetrical, isopolar rarely apolar; tricolporate, often porate. Shape commonly oblatespheroidal to prolate-spheroidal, with some suboblate to subprolate types. Tectum echinate to echinolophate, often non-echinate. Tectum in-between the spines or spinules is sub-psilate, or perforated to striate. On the basis of the exine pattern, 4 distinct pollen types are recognized viz., Pollen type-I: Dicoma tomentosa, Pollen type-II: Eclipta prostrata, Pollen type-III: Echinops echinatus and Pollen type-IV: Launaea nudicaulis. Within the pollen types, pollen characters are significantly sufficient for characterization of the species. An interesting correlation observed is that the taxa having spiny capitula have a mostly non-echinate or spinulose tectum with very thick exine (7-25 µm). Key Words: Pollen morphology, Compositae, Eurypalynous Compositae Familyasının Pollen Morfolojisine Katkılar Özet: Compositae familyasının 18 sınıfına ait 24 türünde pollen morfolojisi ışık ve scanning elektron mikroskopik olarak incelendi. Elde edilen veriler bu familyanın eurypalynous tabiatında olduğunu destekliyor. Pollen karakterlerine göre bu sınıfın (grubun) sınırları tam olarak belirlenmemiş değil. Pollen tanecikleri genellikle radial olarak simetrik, izopolar, ender olarak da apolar; tricolporate ya da daha sıklıkla porate olduğu görüldü. Formu (yapısı) çoğunlukla oblate-spheroidal’den prolatespheroidal’e kadar değişmekte olup bazen sub-oblate’den sub-prolate tiplere kadar değişen