Pollen morphology of the family Grossulariaceae and some taxonomical implication

Abstract

In this paper, we present results of palynomorphological studies of 45 species and 71 specimens of the family Grossulariaceae that are native or cultivated in the Russian Federation and adjacent regions. Pollen was studied with light microscopy, a confocal laser scanning microscope and a scanning electron microscope. Pollen grains of Ribes species are radially symmetrical and isopolar, spheroidal, rarely ellipsoidal and medium-sized (15 to 40 µm). We describe three pollen morphological types in the family: (1) 4-porate type in the subgenus Grossularioides, with echinate mesoporium and atectate exine; (2) 4-7-colporate with 6-12 endopori type in the subgenus Grossularia and the section Heritiera, with psilate, microperforate, rugulate or microechinate mesocolpium and tectate exine; and (3) 4-10-porate-orate type in R. inerme from the subgenus Grossularia and in all other currant taxa except section Heritiera, with psilate or rugulate mesoporium and tectate exine. Pollen data of all studied Ribes species attest to isolation of the family Grossulariaceae based on aperture types and fine pollen morphology; pollen types agree with some taxonomy groups. The content of subgenera and sections and position of some species are discussed.