Abstract
Nineteen double monosomics of Avena byzantina cv. Kanota (i.e. DMk-9 series) were obtained from 19 monosomics pollinated with another monosomic Mk-9. Several characteristics of the double monosomics lacking a chromosome 9 in common were examined. It was considered that a gene for awn formation is located on chromosome 8. There observed a non-allelic gene action for awn development between the epistatic suppressor gene on chromosome 9 and the promotor gene on chromosome 8. Selfed seed fertilities of DMk-9 series varied greatly, being divided into three fertility groups 0-10%, 22-39% and 45-65%. It suggests three different chromosome interactions between chromosome 9 and the other 19 chromosomes. The double monosomics which had high frequency of trivalent formations showed high selfed seed fertility in comparison with those which had high frequency of univalents. The progeny of double monosomics showing low selfed seed fertility had a tendency of nearing the euploid condition in chromosome number. From this study, 19 monosomes of hexaploid oats were identified.
