关键词: 桃蛀螟, 高效氯氟氰菊酯, 亚致死效应, 年龄-龄期两性生命表, 繁殖力

Abstract: 【Aim】 This study aims to explore the sublethal effects oflambda-cyhalothrin on Conogethes punctiferalis, so as to provide a theoretical basis for its scientific application in field management of this pest. 【Methods】 The 48-h toxicity of lambda-cyhalothrin to the 3-day-old adults of C. punctiferalis was determined using the residual film method. Sublethal concentrations (LC₁, LC₅ and LC₁₀) of lambda-cyhalothrin were applied to the 3-day-old adults of C. punctiferalis, the adult longevity, fecundity and survival rate of the F₀ generation, and the larval and pupal duration, fecundity, hatching rate, pupation rate and emergence rate of the F₁ generation were observed and recorded. The age-stage, two-sex life table was constructed for the F₁ generation. 【Results】 Within 48-h exposure, the LC₁, LC₅ and LC₁₀ values of lambda-cyhalothrin against the 3-day-old adults of C. punctiferalis were 0.233, 0.601 and 0.995 mg/L, respectively. Exposure of the 3-day-old adults of C. punctiferalis to LC₁, LC₅ and LC₁₀ of lambda-cyhalothrin resulted in reductions in the average number of eggs laid per female by 5.56%, 24.55% and 51.06%, respectively. After the 3-day-old adults of C. punctiferalis were exposed to LC₁₀ of lambda-cyhalothrin, the adult longevity of the F₀ generation was significantly shortened by 1.60 d, and the oviposition period significantly decreased by 1.29 d, as compared to those in the control group exposed to acetone. The results for the F₁ population showed that, in the treatment groups with LC₁, LC₅ and LC₁₀ of lambda-cyhalothrin, the survival rates at the egg stage decreased by 8.70%, 13.75% and 30.38%, respectively, the average number of eggs laid per female decreased by 38.05%, 30.75% and 24.84%, respectively, and the survival rates at the pupal stage decreased by 2.70%, 13.87% and 27.68%, respectively, as compared to those in the control group. In addition, in the treatment groups with LC₁, LC₅ and LC₁₀ of lambda-cyhalothrin, the peak values of the age-specific reproductive rate (f_x) curve in the F₁ generation of C. punctiferalis decreased by 39.76%, 34.68% and 39.56%, respectively, and the pre-oviposition period, the peak of the female age-specific fecundity, intrinsic rate of increase (r), finite rate of increase (λ) and net rate of increase of the F₁ generation (R₀) were all significantly reduced as compared to those in the control group. 【Conclusion】 Sublethal concentrations of lambda-cyhalothrin significantly reduced the longevity and fecundity of the F₀ generation of C. punctiferalis, and also caused a significant decline in the number of eggs laid of the F₁ generation, thereby suppressing population growth. The results of this study provide a theoretical foundation for the scientific application of lambda-cyhalothrin in the management of C. punctiferalis.

Key words: Conogethes punctiferalis, lambda-cyhalothrin, sublethal effect, age-stage, two-sex life table, fecundity