Abstract: To identify the relative fitness of propargiteresistant strain of Tetranychus cinnabarinus, a propargiteresistant strain (PRR34) was established after 34generation selection of the susceptible strain (SS) by using propargite. The differences in development, reproduction, and population parameters between these two strains were analyzed by comparing experimental population life table. The result showed that after 34generation, the resistance ratio of PRR34 increased to 37.78fold. Compared with SS, the hatching rate of eggs, duration of development stages, and generation time of PRR34 showed no difference, but its preoviposition period significantly increased by 37.07%, the fecundity of single female decreased by 14.61%, and the ratio of female/male (♀/♂) increased by 23.38%. The survival curve was determined as Deevey I according to Weibull distribution, and the parameter c for SS and PRR34 were 2.04 and 2.38, respectively. The population tendency index, intrinsic rate of increase (r_m), and net reproduction rate (R₀) were 123.78, 0.24 and 25.34 for SS, and 111.91, 0.26 and 28.99 for PRR34, respectively. Besides, the relative fitness of PRR34 was 1.14, which showed advantage over SS. In conclusion, compared with SS, the fecundity of single female of PRR34 decreased, but its female ratio and population fitness increased, which may result in the expansion of the resistant strain population and the increase of difficulty for pest control.

Key words: temperature sensitivity., soil enzyme kinetic parameter, soil organic carbon mineralization rate