| Cytotaxonomy, as an important branch of comprehensive taxonomy, not only has offered plentiful the knowledge of cytology to taxonomy, but also impelled the classical classification to a progress in technique method. Phylogenetic and evolutional analyses belong to a new content of taxonomy. Morphological, physiological and ecological characters and their differences are result of gene and gene expression regulation. Relationship revealed by cytotaxonomy, which based on gene vector chromosome, is an improvement and examination of original classification and investigation of speciation mechanism and their evolution direction.Testes from grasshoppers representing 15 genera 42 species of Oedipodiae were sampled in this paper. Testis squash technique was used for preparation of chromosomes and method of BSG (Barium hydroxide / Saline / Giemsa) was adopted for C-banding staining. Then Leica cell image workstation was used to collect digital micro images. Image analyses were performed with lmageProPlus4.5 software and results were saved in EXCEL for consequent statistic operation and obtaining chromosome patterns. 4 indexes were chose, such as chromosome karyotype, C-band pattern, chromosome behavior and B chromosome for comparative analyses, and adopted SPSS to reconstruct dendrogram. Combined with studies on insect morphology and insect geography, we made a detailed analysis and speculation on the relationship of taxa concerned. Finally we got the conclusions as follows:1.The number of chromosomes in grasshoppers of Oedipodiae is 2n =23=22+XO. All chromosomes are telocentric chromosomes. Most of the genome formulas are 3L+6M+2S+X and 3L+7M+1S+X. In another words, most grasshoppers have 3 pairs of large chromosomes, 6-7 pairs of medium ones, 2~3 pairs of small ones and most of X chromosomes are medium and rank 4-7 in genome formula. Positive centromeric bands were found in all chromosomes, but few intercalary and telomere ones. The content of heterochromatin converges between 10% and 15%. Frequencies of chromosome crossover fluctuate between 6.5-10. Most of chiasma in chromosomes of Bryodema, Angaracris, Bryodemella and Compsorhipis are proximal chiasma and others are intercalary chiasma. Six species are found the existence of B chromosomes in cell meiosis phase.2.The method of adopting appropriate indexes to compare different genera and species, and then reconstructing dendrogram with SPSS program is proved to be effective and reliable, which is validated by studies on insect morphology and insect geography. This method pioneers in insect systematics.3.Cluster analysis of 15 genera of Oedipodiae in SPSS showed that the relationship of Bryodema, Angaracris, Bryodemella and Compsorhipis is closer than others. So it is reasonable to group the four genera to one subfamily-Bryodeminae.4.Bryodema kozlovi and Boydema ngroptera have a close location in the clustering, which shows their similarity of chromosomes. Their cytogenetic similarity is also revealed in the chromosome behavior and C-banding. We speculate that they were directly evolved from one species considering their significant morphological difference and confined geographical distribution.5.Sphingonotus tsinlingonsis and Sphingonotus mongolicus are very similar to each other in the phenotype, and slight differences exist in size of the organism and breadth of mesosternal interspace. In the clustering, they are partitioned by Sphingonotus yamlkensis and Sphingonotus ningsianus, which show that these two species are closer to Sphingonotus mongolicus. In C-band patterns, Sphingonotus ningsianus and Sphingonotus mongolicus both showed positive centromeric bands and one intercalary band in 9th chromosome. So a conclusion can be drawn that it is correct to define them as two species.6.In Oedaleus, Ritchie (1981) merged Oedaleus manjius into Oedaleus infernalis and considered Oedaleus asiaticus as a subspecies of Oedaleus decorus. Our results disagree with this revision. From the clustering based on chromosome r...
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