Morphology and Cytology of Different Aneuploids in Avena sativa L

Abstract

In a study of the progenies derived from mono-trisomic genotypes of Avena sativa (2n=6x=42), the effect of deletion of a chromosome was more deleterious than a duplication on plant height and yield components. The combination of a duplication and deletion in nulli-trisomic progenies did not produce a more deteri-mental effect than in nullisomic condition. All other genotypes which were monosomic for each chromosome of the complement were as vigorous as the euploid one's and showed a relatively high degree of fertility.
Meiotic behaviour of euploid and aneuploid genotypes clearly indicated that diploid-like pairing was under genetic control, but not completely dependent upon allopolyploidic origin. Homologous chromosome pairing ensured regular assort-ment and disomic inheritance together with consistent maintainance of genetic duplication.