Effect Of Climatic Factors On The Individual Development And Brood Amount Of Dendrolimus Punctatus

Dendrolimus punctatus (Walker) is one of the main forest pine pests, major harm to Pinusmassoniana Lamb. The climate was one of the important physical and chemical factors to affectindividual development and population reproduction of D.punctatus. In recent decades, global climateshowed significant warming trend, which greatly affected the occurrence of forest pest disasters. Undercertain conditions, temperature, precipitation and the time of sunshine had an impact on developmentduration and egg-hatching rate of D.punctatus’s eggs, and development duration, pupation ratio of D.punctatus larvae, and weight of pupal cocoon, eclosion ratio of pupae and number of egg produced byfemale adult. In this study, D.punctatus was the object, on the basis of analyzing climatic factors toaffect D.punctatus disaster, we in-depth studied the effects of temperature on the development of D.punctatus eggs and larvae, and imago reproductive capacity, the main conclusions were obtained asfollows:1. The main climate factors which affect D.punctatus disaster are temperature and precipitation,among which the temperature of the first winter and early spring were the first factors. There was apositive correlation between them, and summer precipitation was the second factor, a negativecorrelation between them;2. Strong sunlight can significantly shorten the developmental period of D. punctatus’s eggs, buthad no significant effect on hatchability;3. High temperature pulse below38℃had no significant effect on the developmental period of D.punctatus’s eggs, but the high temperature pulse of41℃can significantly shorten the developmenttime of the egg, and can also reduce egg hatchability;4. In the range of20-30℃, D. punctatus’s developmental progress accelerated with the increaseof temperature, but the pupation rate, pupae weight, brood amount and pupae eclosion rate achieve itsmaximum at27.5±1℃, indicating that27.5±1℃was the most conducive to D. punctatus’sdevelopment, thus causing population growth and occurrence of disasters.