Effects of Elevated CO(2) on the Fitness of Three Successive Generations of Lipaphis erysimi

SIMPLE SUMMARY: Global warming caused by the increase in atmospheric CO(2) concentration is becoming a major environmental issue. Lipaphis erysimi is one of the most damaging pests of cruciferous crops worldwide, and L. erysimi has strong adaptability to the environment and reproductive capacity. The age-stage, two-sex life table is currently used by many researchers in place of the traditional age-specific life table, providing many details such as fitness and potential damage. In this study, the individual fitness and population dynamics parameters of three successive generations of L. erysimi were analyzed using the age-stage, two-sex life table. The results show that a high CO(2) concentration had a cumulative effect on the survival rate and fecundity of L. erysimi, and elevated CO(2) had a negative effect on the individual fitness parameters of L. erysimi. The life expectancy (e(xj)) is significantly lower in elevated CO(2) than that in ambient CO(2) treatment in the three successive generations, indicating that L. erysimi was more sensitive to CO(2) concentration and the life of L. erysimi was shortened under elevated CO(2). Additionally, we can find that elevated CO(2) has a short-term effect on the population parameters, including the intrinsic rate of increase (r) and finite rate of increase (λ) in L. erysimi. Through the data from this experiment, we believe that the individual and population fitness of L. erysimi will be decreased under elevated CO(2), which indicates that the damage caused by L. erysimi may be reduced in the future with increasing CO(2) levels. ABSTRACT: To assess the effect of elevated CO(2) on the development, fecundity, and population dynamic parameters of L. erysimi, the age-stage, two-sex life table was used to predict the individual fitness and population parameters of three successive generations of L. erysimi in this study. The results show that a significantly longer total pre-adult stage before oviposition (TPOP) was observed in the third generation compared with the first generation of L. erysimi under the 800 μL/L CO(2) treatment. The fecundity is significantly lower in the 800 μL/L CO(2) treatment than that in the 400 μL/L CO(2) treatment in the third generation of L. erysimi, which indicates that elevated CO(2) had a negative effect on the individual fitness parameters of L. erysimi. Additionally, the life expectancy (e(xj)) is significantly lower under the 800 μL/L CO(2) treatment than that under the 400 μL/L CO(2) treatment in the three successive generations. A significantly higher intrinsic rate of increase (r) and finite rate of increase (λ) were found in the second generation compared with those in the first and third generations of L. erysimi under the 800 μL/L CO(2) treatment. Moreover, significantly lower r and λ were observed under the 800 μL/L CO(2) treatment compared with those under the 400 μL/L and 600 μL/L CO(2) treatments in the first generation of L. erysimi, which indicates that elevated CO(2) has a short-term effect on the population parameters (r and λ) of L. erysimi. Our experiment can provide the data for the comprehensive prevention and control of L. erysimi in the future with increasing CO(2) levels.