Studies On The Chromosomes Of Chinese Deltocephalinae (Hemiptera: Cicadellidae)

Male meiosis karyotypes of 14 tribes, 25 generas, 36 species of Deltocephalinae in Deltocephalini,Athysanini,Scaphoidenini,Chiasmini,Opsiini,Hecalini,Platymetopiini,Goniagnathini,Macrostelini,Stenometopiini,Paralimnini,Penthimiini,Mukarini were studied in this paper, and the relative volumes of every chromosome were calculated. The conclutions were:1. The present paper deals with meiosis and chromosomes in 36 species of Deltocephalinae, among which 28 species are cytologically studied for the first time. The chromosome numbers vary from 2n=10 to 20, and the predominant type is 2n=12(10+XO). The sex determine is XO type in all species, and no XY was discovered here.2. In Deltocephalinae, the chromosome numbers vary from 2n=8 to 28, with the predominant type of 2n=18(16+XO), and 2n=12 also has a high frequency. Positive trend on chromosome number evolution was not found.3. It is common to show a bouquet stage at prophase in Deltocephalinae.4. At metaphase I, the spatial disposition mode of the chromosomes in the nuclear is: the autosomes are parallel, vertical with the equatorial plane, and the centric regions are at the equatorial plane. The X chromosome is at one side of the nuclear which is far away from the equatorial plane, and also far away from the autosomes.5. The relative volumes of species in the same genera are similar, and the diversity is aways represents between the X and the largest autosome.6. The numbers and relative volumes are relative stable only in the same genera, and at higher taxonomic categories they are of great difference.