Karyotyping Analysis and Genome Size Determination of Two Sechium edule Varieties
In this study,the karyotype,genome size,chromosome number and ploidy of the main vari-eties of green and white Sechium edule in Huishui County,Guizhou Province were studied by chro-mosome dissection and flow cytometry.The results showed that both white-skinned and green-skinned Sechium edule were diploid and had 28 chromosomes.The karyotype formulas of white-skinned Sechium edule and green-skinned Sechium edule were 2n=2x=28m,the karyotype of white-skinned Sechium edule was type 1B,and that of green-skinned Sechium edule was type 1C.The asymmetry coefficient of green-skinned Sechium edule was 52.38%,and the asymmetry coefficient of white-skinned Sechium edule was 52.07%,by flow cytometry,the genome size of white-skinned and green-skinned Sechium edule was(0.73±0.02)Gb and(0.70±0.02)Gb,respectively.