Fluorescent chromosome banding patterns of several species in the Cupressaceae sensu stricto

摘要

Thirteen species among eight genera in Cupressaceae sensu stricto were studied on somatic chromosome bandings by sequential fluorescent staining with chromomycin A₃ (CMA) and 4',6-diamidino-2-phenylindole (DAPI). All species were diploid (2n=22) and had symmetric and homogeneous karyotype. Two CMA-bands appeared on chromosome complements of Callitris rhomboidea , Chamaecyparis obtsusa , Ch. pisifera , Cupressus lusitanica , Juniperus rigida , Microbiota decussate , Platycladus orientalis , Thuja plicata , and T. standishii . Actinostrobus pyramidalis , Ch. lawsoniana , and Cup. duclouxiana had four CMA-bands. Cupressus macrocarpa had six CMA-bands. CMA-bands appeared at interstitial region of chromosomes and their location was coincided with the site of secondary constrictions in all species. Microbiota decussate had unique weak CMA-bands at the proximal regions of 10 chromosomes in addition to two bright CMA-bands. After DAPI-banding whole chromosome arms of each species fluoresced excepting for region of CMA-bands. Cupressus duclouxiana had weak DAPI-bands on few chromosomes.