The Analysis And Identification On The Karyotype And Giemsa-C Banding Pattern Of The Ae.tauschii- H.vulgare Amphidiploid

The karyotypes and the Giemsa-C banding patterns of Aegilops tauschii (85A-34) and Hordium vulgare (H2) and regenerated plants from embryo callus of hybrids between Ae.tauschii and H.vulgare (2n=28) were confirmed by karyotype analyzing and Giemsa-C banding technique in this study, thus proved that the regenerated plants from embryo callus of hybrids between Ae.tauschii and H.vulgare (2n=28) were spontaneously chromosal doubling amphidiploid.Studies showed that the chromosomes of barley H2 from No.1 to No.6 are all the central centric chromosomes but the No.7 is the submedian centric chromosome. The No.6 and the No.7 have distinct satellites, the satellite of the No.6 is larger than that of the No.7, and its kartype formula is 2n=2x=14=12m(2SAT)+2sm(2SAT). The chromosomes of Aegilops tauschii (85A-34) are the central centric chromosomes except that the chromosomes of No.5 is the submedian centric chromosome.Its kartype formula is 2n=2x=14=12m+2sm(2SAT).The kartype formula of regenerated plants from embryo callus of hybrids between Ae.tauschii and H.vulgare is 2n=4x=28＝24m(2SAT)＋4sm(4SAT),which consisted of the D genome and the H genome and were real amphidiploid.By Giemsa--C technique, the chromosomes of Aegilops tauschii (85A-34) and Hordeum vulgare (H2) and Ae.tauschii- H.vulgare amphidiploid were all produced clear bands, the terminal band, centromeric band, secondary constrition band and rich intercalary bands were displayed distinctly, thus the corresponding Giemsa-C banding patterns were confirmed. Studies showed that the Giemsa-C banding patterns of Ae.tauschii- H.vulgare amphidiploid is much in accord with that of its two parents, and this further proved that the regenerated plants from embryo callus of hybrids between Ae.tauschii and H.vulgare (2n=28) were spontaneously chromosal doubling amphidiploid. At the same time, the mechanism of chromosomal Giemsa-C banding was further studied in this article, the reason why the earlier metaphase of chromosome can be produced distinct bands more easily was put forward, and the result was considered that whether the dyestuff can be combined ornot and its extent of the combination were directly decided by the distance of the bases in the DNA and the amino acids in the protein during the chromosome's banding to effect the banding. The important cytological evidences for utilizing this plant were provided and the theories of somaclonal variation and chromosome banding were further riched in this study.