The multicolored Asian ladybeetle Harmonia axyridis is characterized by polymorphism of the elytral pattern. Melanization in Harmonia axyridis is crucial for their elytral coloration, but the molecular mechanisms are not fully understood in this species. Tyrosine hydroxylase (TH) and dopa decarboxylase (DDC), two key enzymes in the melanin pathway, convert tyrosine and dopa into dopa and dopamine, respectively. In this study, it was to determine the role of TH and DDC of Harmonia axyridis (HaTH and HaDDC) in body and wing pigmentaion produced via melanin pathway. The cDNA sequences of HaTH and HaDDC were cloned to perform RNAi-based functional analysis. Injected dsRNA to the 4th larvae caused knockdown of target genes, and it was verified by quantative realtime PCR. Both TH and DDC RNAi adult show loss of black pigmentation in their body and wing pigmentaion. These results is expected to be helpful to investigate polymorphism by melanin pigment in Harmonia axyridis.

For the studying of effects of matrine and azadirachtine against Aphidius colemani, it was conducted to test the toxic effect of ecofriendly materials. Matrine and azadirachtine are active ingredient of the most commonly used eco-friendly insecticidal materials against insect pests. The effects of materials are investigated by spraying solution to mummies and adults in laborartory condition (Temp: 25℃; 16L:8D; RH: 50-60%). Each materials was diluted and treated with 5 concentrations, 10 wasps for each replications and 3 replications for each concentration. Fitness of A. colemani was assessed by measuring survival rate, emergence rate, longevity and fecundity. Wasps adults were used for experiments within 48 hours after their hatching. Emergence rates were checked for 12 days after spray to mummies of A. colemani, and survival rates were checked at 24 and 48 hours after vial test for adult parasitoids with 10% sugar solution. Adult wasps were exposed to dry residue of material for 24 hours. Longevity was monitored every 12 hours and fecundity was measured by the number of mummies produced by A. colemani adults.