Chromosome Polymorphism of Three Populations of the Grasshopper Yunnanacris yunnaneus (Ramme)

Purpose Yunnanacris yunnaneus (Ramme) is an endemic species of China, in order to understand the cytogenetic characteristics of different populations of Y. yunnaneus.

Method The chromosome karyotype and C-band patterns of the three geographic populations of Y. yunnaneus have been studied using squashing and BSG chromosomal banding technique in this paper.

Results Three populations of Y. yunnaneus have a diploid chromosome number of 2n (♂)=21, with an XO sex-determining mechanism and a diverse chromosome type consisting of telocentric, subtelocentric, metacentric and submetacentric chromosomes. The autosomes can be divided into 3-4 large, 3-6 medium and 1-3 short groups according to their relative length, the X chromosome is the large one in size. C-banding reveals that the three populations have a simple type only with centromeric and terminal C-band, and the numbers are different among populations, and the most having 21 C-bands. The average value of heterochromatic content in this species is 20.99%.

Conclusion The three populations show obvious differences in the two aspects of C-band karyotype and external morphology, and which provide an important references for further study of the population differentiation of this species.