| Varroa mite is an ectoparasite of honeybee and it distributes world widely. The bee keeping industry around world has been severely impacted by the mites. Therefore, to find a new way to control Varroa mites is badly needed. In this paper, the epidemic investigation of Varroa mite paratized in A mellifera and A.carena , laboratory research work in comparison of reproductive characteristics of Varroa mite in A mellifera or A.carena brood cells artificially transferred from A mellifera or A.carena colonies and molecular identification of Varroa mites infecting A mellifera and A.carena were carried out respectively to study mite's stock structure, parasitic patterns, reproductive characteristics, harmfulness for honeydees as well as the distribution of Varroa mites in China. The main results are as follows:1. Study on mtDNA CO-1 gene sequences of Varroa mites in China showed that Varroa mites parasitizing A mellifera conolies are V. destructor Korea genotype. Varroa mites parasitizing A cerana conolies are V. destructor China genotype, V. destructor China2 genotype and V. destructor Vietnam genotype respectively. Our results demonstrated initially that all Varroa mites parasitizing either A mellifera or A. cerana are V. destructor . Up to now, no V. jacobsoni has been found in China. Therefore, there is an error in the statement in Chinese bee text book that mites in Chian is V.jacobsoni.2. Investigation of Varroa mite infected in A mellifera and A.carena in China.It was found for the first time that the rate of Varroa mites infected A mellifera and A.carena was reduced gradually from South to North in China, suggesting that geographic differences affect the parasite of Varroa mites in honeybee colonies. Our survey also showed that A.carena colonies in Guangdong province was damaged by Varroa mites which was considered to be not harmful to A.carena before.Under natural conditions, Varroa mites reproduced only in drone cells but not in worker cells in cononies of A.carena, despite worker cells were invaded by Varroa mites in large quantity. The parasited rate is very low in cononies of A.carena. However, the parasited rate is 100% in cononies of A mellifera .The results were similar to the previous results.Development of the Varroa mites population in cononies of A.carena are affected mainly by the number of drone brood cells in the colonies.3. Under artificially transferring conditions,Varroa mites from cononies of A. mellifera reproduced in drone and worker cells not only of A. mellifera and but also of A. carena. However, Varroa mites from cononies of A.carena only reproduced in drone cells of A. carena but refrained from reproduction in other 3 type of brood cells of A. mellifera and A.carena. The results indicated that Varroa mites from A. mellifera and A. carena are different and with various reproductive capability. Furthermore, mites from same kind of host reproduce differently in various brood cells, with the best reproductive ability in drone cells of A. carena and the significantly higher mean number of offspring in drone cells of A. carena than that transferred into worker brood cells of A.carena, drone brood cell and worker brood cells of A. mellifera, respectively. The results suggested that both the type of brood cell of honeybees and Varroa mite from different host affect the reproductive ability of Varroa mites.4. With the same brood in different type of brood cells, Varroa mite favors the smaller cells and reproduces more in smaller cells than in larger cells, indicating smaller cells are more suitable for V. destructor to stay and reproduce.5. when bees were parasited by Varroa mites, the concentration of hemolymph protein of bees increased significantly and the components of hemolymph protein changed greatly. The results showed that A. Mellifera could develop a resistance to parasite by Varroa mites.
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