Pollen morphology of Crocus reticulatus Steven ex Adams (Iridaceae)

Abstract

Pollen of wild saffron (Crocus reticulatus Steven ex Adams) was analyzed using scanning electron microscope in order to contribute to palynomorphological and taxonomic research of apiflora of Serbia. Crocus reticulatus is a herbaceous perennial plant, growing from 5 to 15 (18) cm in height, with usually solitary pale-lilac to whitish flowers with 3 wide stripes on the outer surface of the tepals. This species belongs to the Pontian-Mediterranean floral element, inhabiting dry grassy or rocky slopes, steppe meadows, sandstone, and bright forests. In Serbia, it is usually found growing in the vicinity of Belgrade, on Vršac Hill and Mt. Fruška Gora, near Kladovo and Kostolac and also in Deliblato Sands where material for this analysis was collected from. The following morphological characteristics of pollen were examined:polarity, shape, size (pollen diameter), apertures, ornamentation and symmetry. Observations and measurements were performed on a sample of 25 pollen grains for each of the analyzed morphological characters. Pollen grains of C. reticulatus are radially symmetrical, spheroidal in shape and large-sized. The average pollen diameter is 66.71±1.57 µm. The exine has extensive or spiral shallow furrows (spiraperturate). Exine ornamentation is microechinate-microperforate. The tectum is covered with minute ehini averaging 0.69±0.15 µm in height, irregularly distributed between the perforations. The microechini average number per sample area of 5 µm x 5 µm is 5.9 ± 0.87