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Pollen germination and tube growth of fruit trees are the most important characteristics related to pollen quality. An effective fertilization requires the high rates of germination and fast tube growth. For economic reasons a higher rate of pollen germination is needed in fruit trees. The objective of this study was to investigate the cytological characteristics of pollen grains and analysis the germinative potential and the effect of the different sucrose concentrations on pollen germination and tube growth of some Prunus amygdalus L. Batsch varieties: A1, A2 and Tuono, from Research-Development Fruit growing Station, Constanta, Romania, at laboratory conditions. There were studied the following parameters: the cytological viability and germination capacity of pollen grains, determined by the technique using the formation of formazan (reagent that colour in red only the viable pollen grains and the division of their initial nucleus); the number of germinative pores (the main criteria for the identification and delimitation of polyploid species) determined by treating pollen grains with H2SO4- CH3COOH (for hydrolyzation of exine and intine), followed by identification and counting of germinative pores; the cultures of pollinic tubes in sucrose medium by different concentrations (5%, 10%, 15%), followed by carmine-acetic identification under the light microscope for the germination level, observed at every 30 minute (Epifluorescent Microscope Fluo 2 with a Bel Photonics DV-1300 digital camera). The usual shape of pollen grains was oval or triangular; the medium diameter of pollen grains was 19-21μm; the viability and fertility of pollen grains was between 88,6 and 91,6 % and the number of germinative pores for each pollen grain was 3. For the germination and the formation of pollinic tubes, the comparative analysis of the two hybrids and a variety of almond has shown that at the Prunus amygdalus Tuono was observed the highest germination capacity, on a general nutrient medium with sucrose 15% after 2-hour time of germination (90,1%), followed by the general nutrient medium with sucrose 15% after 1-hour time of germination (81,2%). This variety appears to be the most fertile. The following variety as fertility has proved to be Prunus amygdalus A2, with a maximum germination capacity observed on a general nutrient medium with sucrose 15% after 2-hour time of germination (84,1 %). The results of our research may represent genetic and ecophysiological indexes for the Prunus amygdalus Batsch varieties under study. [ABSTRACT FROM AUTHOR]