Portal de Periódicos da CAPES

Palynological analysis of five selected Onosma taxa

2008; Springer Nature; Volume: 63; Issue: 2 Linguagem: Inglês

10.2478/s11756-008-0026-y

1336-9563

Filippo Maggi, Vladislav Kolarčik, Pavol Mártonfi,

Plant Parasitism and Resistance

Pollen size and exine structure of the following five Onosma L. species from Slovakia and Italy were studied by light and scanning electron microscopy: Onosma echioides, O. tornensis, O. visianii, O. arenaria, and O. pseudoarenaria. Among the taxa studied, O. echioides has the smallest pollen grains in average (10.5–17.5 × 8.0–14.5 µm), and O. pseudoarenaria the largest grains in average (15.3–20.5 × 12.3–16.3 µm). Pollen grains of all 5 species are small sized, 3-syncolporate, subprolate, heteropolar, with ovate equatorial outlines and circular to rounded triangular polar outlines; the tectum is microechinate. A positive correlation is found between pollen size and chromosome number. The value of pollen characters for taxonomic purposes and the position of the taxa studied within the genus Onosma are discussed.