The micromorphological characteristics of the pollen grain sculpture is one of the most important diagnostic traits in plants. Pollen grains in various species of the subfamily Prunoideae are characterized by variations in size, shape and exine sculpture. In the present work, for the first time, the micromorphology of pollen grains of fourteen cultivars from five fruit tree species of the genus Prunus was compared. Morphometric observations and analysis of pollen grains were performed using light and electron scanning microscopy. In terms of size, the pollen grains studied were classified as medium sized and large. Their shape was determined to be prolate, subprolate, or prolate spheroidal. The striae in the exine of P. armeniaca run parallel and can be branched or curved. The sculpture of P. persica grains shows elongated extending paralel regular and irregular striae, dichotomously branched. Regularly arranged, or at places branched, striae are found in the exine of P. avium pollen grains. The ornamentation of P. cerasus grains is composed of elongated striae, sometimes slightly curved or with a tendency to intertwine. The exine of P. domestica grains is characterized by forked, arched striae. The stria thickness differs significantly between cultivars within the species, while the groove width differs only between some species and cultivars. The obtained results on the exine sculpture of pollen grains can be used in the taxonomy of species of the genus Prunus.

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