Restitution Gametes in Sugar Beet Primary Trisomics

• Published in: The Journal of heredity 1988-07, Vol.79 (4), p.306-308
• Main Authors: Romagosa, I., Cistue, L., Lasa, J. M., Hecker, R. J.
• Format: Article
• Language: English
• Subjects: Agronomy. Soil science and plant productions; Biological and medical sciences; Classical genetics, quantitative genetics, hybrids; Cytogenetics; Fundamental and applied biological sciences. Psychology; Generalities. Genetics. Plant material; Genetics and breeding of economic plants; Genetics of eukaryotes. Biological and molecular evolution; Pteridophyta, spermatophyta; Vegetals
• ISSN: 0022-1503; 1465-7333; 1465-7333
• DOI: 10.1093/oxfordjournals.jhered.a110515

Restitution gametes were observed at the end of the meiotic cycle in five primary trisomic types of sugar beet (Beta vulgaris L., 2n = 18). Nuclear restitution as measured by the percentage of pollen mother cells showing triads or dyads at the sporad stage was less than 2% for four trisomic types. Dosage effects of chromosome 5 seemed to enhance 2n pollen formation. Rants trisomic for chromosome 5 showed triads and dyads at the sporad stage with a frequency ranging from 6 to 48% among plants. Conclusive evidence of sexual polyploidization was shown by the presence of 28 chromosome progeny obtained from 2x × (2x + 1) and (2x + 1) × (2x + 1) crosses. The average frequency of triploids on the offspring of Triplo 5 was 4% in plants of a homozygous trisomic series and 8% among plants of the other available series.