Study of Morphological Characteristics of Pollen Grains of Sambucus nigra L.

Abstract

The aim of the work was to study the general characteristics and significant morphological traits of pollen grains, as the size, shape of pollen grains in Sambucus nigra L. The studies were performed on pollen obtained from genotypes cultivated in Ukraine (Kyiv). Morphology of pollen grain was described for thirteen Sambucus nigra genotypes (SN-1 – SN-13) at the laboratory of Department of Tropical and Subtropical plants of M.M. Gryshko National Botanical Garden.  Pollen grains morphological traits were evaluated using the scanning and transmission electron microscopy. The measurement of morphometric parameters was carried out on 70 pollen grains from each genotype using the AxioVision Rel. 4.8.2.0 program. The measurements were made in micrometer (μm). The length of polar axis (P) and the equatorial diameter (E) of grain, P/E ratio were measured and their variation was compared among studied genotypes. SEM investigations showed that the pollen grains of Sambucus species are small to medium-sized, oblat-sphaeroidal-prolat shape, three-colporate and the exine adornments are of reticulate type without perpendicular thickness. This study showed that there were significant differences the genotypes in all measured factors. The polar axis and equatorial diameter of pollen grains values were varied from 22.11 to 29.07 μm and from 11.98 μm to 17.29 μm, respectively. This study confirmed small differences among the genotypes in all measured factors with variation coefficient in the range 2.87–6.02 %. It was noted that diversity of surface sculpturing of pollen grains in combination with shape and sizes of them enables to use complex of thin morphologic signs for Sambucus nigra pollen identifications.