Study On The Indoor Artifical Breeding,the Larvae Instar Determination And The Ovipositing Characters Of Monochamus Alternatus

Monochamus alternatus Hope is an important tree trunk borer and the main vector insect of Bursaphelenchus xylophilus. In this paper, Monochamus alternatus artificial rearing, larvae instar division and the adults breeding characteristics were studied. The results were as follows:(1Configurable semi-artificial diet of Monochamus alternatus could meet the nutritional needs of growth and development of larvae. Monochamus alternatus adult and pupal weight of artificial breeding was more than the mature larvae, but pupae duration both had no significant difference. The pupation rate of artificial was above80%, and emergence rate was over90%. The mean eggs of Monochamus alternatu which indoor rearing were118.97, and the hatching rate was about85%. Thus, the self-developed artificial diets can successfully satisfied Monochamus alternatu larval development.(2) Although cedar satisfied the nutritional needs of larvae development, and adults can also feed cedar branches, but it can not satisfied the needs of adult nutritional supplements. Adult feeding only on cedar branches can not spawning. Therefore, we can deduce that in pure cedar forest, Monochamus alternatus can not complete a generation.(3)Monochamus alternatus larval reared under different nutritional conditions was all5instar. The duration of larval development were60.7d,70.Id,85.8d, respectively. Monochamus alternatus can be reproduced3to4generations a year, but some indoor rearing larvae enter diapause on October to December. As to the highest head width and pronotum width values among the three diets, and the shortest developmental period, diet I was most favorable for the development of the larvae. All value of Monochamus alternatus larval head width and pronotum width, which feeding on diet I, was the highest among the three diets. It means that different nutritional conditions on the development of larvae will have a significant effects. Larval growth of head width and Pronotum were both following to Crosby, and Brooks, therefore, larval head width and pronotum width can be used as indicators of larval instar division. Brooks index average of larval head width and pronotum were1.34(Dyar constant) and1.31, and there was no significant difference between them. It is positively correlation between the growth of head and pronotum.(4)By measuring the eggs and groove, it was clear that the shape of Monochamus alternatus eggs was like rice grain, and the mean length and width were4.19mm,1.38mm. External shape of the notch groove were most similar to " Slotted ", a few were oblong. The mean distance of the groove length, width, depth, and lateral notches carved from eggs were 2.02mm,0.99mm,1.33mm,4.97mm. Through the analysis data showed that the branch diameter and the lateral depth of spawning groove has a positive correlation, and the length of branch diameter and groove has a negative correlation,and the length and width of the groove has a positive correlation. It has no correlation between the branch diameter and distance of egg to carve notches.