Abstract
Meiotic studies were performed on 11 populations of 8 Stipa species concerning polyploidy level, chiasma frequency and distribution, chromosomes association and segregation. All the species and populations studied possessed n=22 (2n=4x=44) chromosome number. The chromosome numbers of 3 species are reported for the first time. The populations and species studied differed significantly in their meiotic characteristics. Meiotic abnormalities observed included laggard chromosome formation, stickiness and cytomixis. Cytomixis led to the formation of aneuploid meiocytes. Unreduced pollen grains were observed in 2 species, which differed significantly in their size compared to the normal (reduced) pollen grains.
