STUDY ON THE DEVELOPMENTAL THRESHOLD AND TOTAL OF EFFECTIVE TEMPERATURE OF THE LAC INSECT IN CHINA

Under natural condition, the developmental threshold temperature for the first, second and third instar larvae and the female adults of K. lacca is 9.1℃,8.8℃,10.2℃ and 18.1℃ respectively,with that of the larval stage being 8.8℃ as a whole. The total of effective temperature for the first, second, third instar larvae, the larval stage and female adult stage are 291.6±44.2℃, 193.4±22.8℃,168.7±44.1℃, 694.2±88.7℃ and 304.9±29.4℃ respectively, while their relative coefficiencies between the developmental durations and total of effective temperature are 0.97, 0.99, 0.93, 0.97 and 0.99 correspondingly. It then appears that temperature exerts decisive influence on the insect during its developmental course.