河南棉蚜种群组成的染色体分析

STUDIES ON THE POPULATION COMPONENTS OF APHIS GOSSYPII GLOVER IN HENAN PROVINCE WITH CHROMOSOME ANALYSIS

The results of experiment using the techniques of chromosome analysis for studying natural population components of cotton aphid, Aphis Gossypii Glover, are reported in this paper. The somatic chromosome preparation of cotton aphid were prepared in the different periods. Karyotype analysis was based on chromosome length and G-banding patterns. The relusts show that the natural population of the aphid is a complex population consisted of the normal karyotype (NK), the 1,2 translocated and 1,3 translocated karyotype (T1-2 and T1-3) aphids. The proportion of each karyotype changes with time. The NK aphids are the dominant population on the Chinese prickly ash and cotton at seedling stage. The T1-2 aphids are the dominant on cotton at the bud and boll stage. The karyotype of aphids on different host plant, such as Chinese prickly ash, pomegranate, rose of Sharon, cotton, and in the different regions such as Zhengzhou, Nanyang, Xinxiang, Shangqiou, Lingbao in Henan Province, were compared. No differences were discovered. In the article, the author discusses the problems of emergence and maintaining of translocated karyotype aphids and believes that these aphids can't be eliminated at the sexual stage because of the rapid reproduction and parthenogenesis characteristic of the cotton aphids.