Monochamus alteatus Hope(Coleoptera:Cerambycidae)is not onlY a serious Dest insect to pine trees but alSO the main vector of pine wood nemadote Bursaphelenchus xylophilus,which causes pine wilt disease.To explore the insecticidal mechanism of insecticides to M alteatus,we chose methamidophos and deltamethrin as the representa-tives of two groups of insecticides(organophosphates and pyrethroids),which arc widely used for pest controlin China and investigated their effects on phosphorylation of proteins from the insect.Phosphorylation of proteins from the insect fat body and head was determined by fn vitro 32P-labelling.In the fat body,deltamethtin obviously reduced basal phosphorylation levels of proteins at 111,95,77,and 44 kDa,but enhanced the basal phosphorylation level of a protein at 138 kDa.However,in the presence of calmodulin but not cyclic adenosine monophosphate(cAMP),deitamethrin increased phosphorylation of the protein at 111 kDa.In the head,deltamethrin inhibited basal phosphorylation levels of proteins at 113,98,and 51 kDa,but potentiated phosphorylation of a protein at 167 kDa activated by cAMP.Methamidophos inhibited phosphorylation of a protein at 44 kDa in the fat body.Although methamidophos did not impact basal phosphorylation levels of any proteins in the head,it inhibiled calcium/calmodulin(Ca2+/CAM) stimulated phosphoryla-tion of a protein at 5 1 kDa.Together.our dam indicate that methamidophos and deltamethrin altered phosphorylation levels of various proteins in thc head and fat body of the pine insect and these two kinds of inseeticides acted on the proteins that call be phosphorylated in the tissues respectively,Which is possibly related to their toxicity.