Abstract: 【Objective】 The ladybird beetle Harmonia axyridis Pallas is a well-known aphid predator and plays an important role as a biological control agent in its native regions. Life table can provide a comprehensive description of the development, survival, and fecundity of a population. The life history of H. axyridis has been studied using the traditional life table in controlled laboratory conditions. However, when released, H. axyridis were exposed to fluctuating temperatures which can significantly change the biological characteristics of insects. The objective of this study is to build life tables for H. axyridis both at constant temperature in the laboratory and at fluctuating temperatures in the greenhouse, and to facilitate the effective use of this species as a biological control agent.【Method】Developmental, survival, and fecundity rate data were analyzed by using the age-stage, two-sex life table under laboratory and greenhouse conditions and the significant differences were compared with t-tests at a 5% significance level by SPSS17.0. Means and standard errors of population parameters were calculated by using the bootstrap method and the significant differences were compared with t-tests by the TWOSEX-MSChart computer program. 【Result】 H. axyridis at constant temperature in the laboratory developed more quickly in the pre-adult stage and were longer-lived compared with those in the greenhouse. Moreover, significant reductions in survival and reproduction of H. axyridis under greenhouse conditions were observed in the curves of s_xj, l_x, f_x and m_x. The life expectancy of H. axyridis decreased gradually with age while the life expectancy were shorter and varied significantly at fluctuating temperatures in the greenhouse. The contribution of an individual to the future population was described by the reproductive value (v_xj) which under greenhouse conditions was lower and more varied than that in the laboratory.According to the age-stage, two-sex life table, the intrinsic rate of increase (r), net reproductive rate (R₀), finite rate of increase (λ), the mean generation time (T) were 0.1395 and 0.0613 d^-1, 257.3 and 13.3 offspring, 1.150 and 1.062 d^-1, 39.7 and 42.7 d, respectively, under laboratory and greenhouse conditions. 【Conclusion】 It revealed significant differences of life history and population parameters between life tables collected under laboratory and greenhouse conditions. The results indicated that at constant temperature, one could under- or over-estimate the values of numerous life-history traits compared to the fluctuating temperatures. There exist some definite errors in the field release application according to life table data obtained by constant temperature, which affects the control effects.

Key words: Harmonia axyridis, age-stage, two-sex life table, experimental population, greenhouse population, population parameters