1. Research Institute of Resource Insect, Chinese Academy of Forestry; Kunming 650224, China; 2. The Key Laboratory of Breeding and Utilization of Resources Insects of State Forestry Administration, Kunming 650224, China
Chromosome quantities, forms and karyotype of seven lac insect species, which are of significant economic value, were analyzed and compared. Several type of chromosomes shape such as stick-alike, ellipse, kidney-alike and dumbbell-alike were found in the seven species. Their chromosome number was all 2n=18. All the chromosomes were composed of metacentric (or sub-metacentric) and telocentric chromosomes. And there were four kinds of chromosomes structure shape: K=10m+8T, K=8m+10T,K=6m+12T, K=4m+14T. The result of karyotype analysis showed that Kerria sindica and K. lacca had a close relationship, of which the chromosome type, karyotypic style and constitution of relative length were in consistent. Kerria pusana and K. nepalensis were similar in the chromosome type and karyotype asymmetry index, which revealed their near homology from chromosomes level. The chromosomes of K. ruralis and K. yunnanensis were both formed with eight metacentric (or sub-metacentric) chromosomes and 10 telocentric chromosomes, indicating the close nexus between them. The karyotype of K. chinensis was different from other six species and it has the far relationship with others. We concluded that the main commercial species of lac insect belonged to K. yunnanensis.