Chromosome identification of seven primary trisomics in inbred rye (Secale cereale L.) by acetocarmine Giemsa C-banding.

Abstract

Seven primary trisomics were isolated in the progeny of autotriploids of an inbred rye line (Secale cereale L.). Each triplicated chromosome was cytologically identified by the improved acetocarmine Giemsa C-banding method. This method elucidates qualitative and quantitative traits of the individual chromosomes in the complement. Chromosomes 1 and 2 were non-satellited, while the others (chromosomes 3, 4, 5, 6, and 7) had secondary constrictions in the short arms with different sizes of satellites. Chromosomes 4 and 5 had clear tertiary constrictions in their long arms. After C-banding, prominent bands were observed on both terminal ends of chromosomes 1 and 3. Chromosome 2 had somewhat weak bands on both terminal ends. The satellites of chromosomes 4, 5, 6, and 7 were heavily stained, but the long arm of chromosome 4 had three weakly stained bands, whereas chromosome 5 had two weak and two still weaker bands. Two weakly stained bands were observed in the long arm of chromosome 6. A prominent band on the end of the long arm and a weak one close to the terminal band were recognized in chromosome 7. A diamond shaped centromere was detected in some cells. These characteristics were cytologically confirmed in all seven types of primary trisomics. Homoeologous relationships to the wheat chromosomes were discussed. Rye chromosomes 1 to 7 in this study are homoeologous with wheat chromosomes and designated as 2R, 7R, 3R, 4R, 6R, 5R, and 1R, respectively.