Staining and slide-preparing technique of chromosome and karyotype analysis of root-tip in Desmodium styracifolium (Osbeck.) Merr.
Objective To investigate the optimal staining and slide-preparing technique of root-tip chromosome in order to provide references for identification of chromosome numbers in Desmodium styracifolium (Osb.) Merr.Methods The root-tips of D.styracifolium was used to study the effects of root-tip length,sampling time,pre-treating solution,dissociation and staining time on slide-preparing for chromosome and karyotype analysis by using a conventional chromosome mounting technique.Results The mitotic index was the highest and morphology was clear when the root tips length was approximately 0.5 cm at 9:00 AM,then pretreated with 0.05% colchicine for 3 hours,fixed with Carnoy solution for 24 h,and dissociated in 1.0 mol/L hydrochloric acid at 60 ℃ for 10 min.Karyotype analysis of D.styracifolium showed that the chromosome number was 22 and the kayotype formula was 2n=2x=22.7 pairs were metacentric (m),3 pairs were submetacentric (sm),and 1 pair were subtelocentric (st).The kayotype of D.styracifolium was type 2A and the kayotype asymmetry coefficient was 60.61%.Conclusion This study provided the best conditions of chromosome mounting technique for root-tip in D.styracifolium.
国家科技期刊平台
NSTL
万方数据
维普
