Aberrant meiosis and spindle abnormalities in Paspalum paspaloides (Michx.) Scribn (Gramineae)

Abstract

Meiotic chromosome behaviour was studied in two collections of Paspalum paspaloides (Michx.) Scribn. In one of these chromosome mosaicism, restitution nuclei, multinucleate microsporocytes and multipolar and divergent spindles were observed. Chromosome mosaicism resulted from abnormal cell cleavage. In microsporocytes exhibiting chromosome mosaicism, the number of univalents per cell decreased as the chromosome number per cell increased. The increase in chromosome number brought it close to the euploid number (2n=60). Chromosome mosaicism never involved any increase above the euploid number. In the other collection, meiosis was relatively normal.