129. N. MIĆIĆ, G. ĐURIĆ, T. JOVANOVIĆ-CVETKOVIĆ, M. CVETKOVIĆ (2018): Pollen functional ability in two indigenous grapevine cultivars in Bosnia and Herzegovina Eur. J. Hortic. Sci. 83(1), 35–41 /doi.org/10.17660/eJHS.2018/83.1.5
A large number of grapevine cultivars have func¬tionally female flowers. The causes of male sterility in these cultivars in the spheres of microsporogene¬sis and pollen morphology are only partially tackled. This study examines microsporogenesis and pollen functional ability in two most economically import¬ant indigenous grapevine cultivars in Bosnia and Her¬zegovina by the evaluation of permanent histological sections and the use of a scanning electron micro¬scope. When observed at the cytogenetic and embry¬ological level, microsporogenesis in cvs. Blatina with sterile pollen and Žilavka with fertile pollen shows regularity, they coincide and there are no differenc¬es in the sequence of differentiation events, except in their timing and duration. In ‘Žilavka’, the develop¬ment of pollen in the anther locule at all sequential events, including pollen release from the tetrad, for¬mation of the structural elements of the exine, phys¬iological and morphological preparations for pollen to be dispersed and its release from the anthers, progresses normally with typical – vital cytogenetic characteristics maintained. In ‘Blatina’, during pollen development in the anther locule upon release from the tetrads and during the formation of the structural elements of the exine, uncontrolled coverage of pol¬len by the exine occurs, ultimately resulting in the formation of inaperturate pollen – morphologically sterile pollen grains.