Karyotype Analysis and Ribosomal DNA Fluorescent in Situ Hybridization in Pennisetum purpureum
ZHAO Li-Juan et al (Department of Life Science,Huai hua University,Huaihua,Hunan 418000)
[Objective]The aim of the study was to identify the chromosomes of Pennsetum purpureum,and know the genome structure and evolution.[Method] Mitotic metaphase chromosomes of Pennsetum purpureum were prepared using flame-drying method and fluorescent in situ hybridization technology,a classic karyotype of Pennsetum was constructed according to chromosome length,centromere position and the number of satellite.Kymogram of mitotic metaphase chromosomes on the basis of the 4'-6-diamino-2-phenylindole dihydrochloride staining pattern was developed,and the distribution characteristics of heterochromatin in the Pennseturm purpureum genome was studied.[Result] By fluorescent analysis there were two pairs of 45S rDNA signals located on different chromosomes,and one pair of 5S rDNA signals mapped on the long arms of chromosome 9.The karyotype of the Pennsetum purpureum was 2n=28=10sm+12m(4SAT)+4st+2T,it belonged to 2C.[Conclusion] The study provided theoretical basis for identification of the choromosomes.