亚致死浓度毒死蜱对小麦禾谷缢管蚜生长和繁殖的影响

Sublethal effects of chlorpyrifos on the growth and reproduction of Rhopalosiphum padi

为探讨毒死蜱对小麦禾谷缢管蚜Rhopalosiphum padi(Linnaeus)的亚致死效应,采用玻璃管药膜法确定了其亚致死浓度(LC10、LC20和LC30),并研究了该浓度下毒死蜱对小麦禾谷缢管蚜生长和繁殖的影响。结果表明:以LC10、LC20和LC30浓度处理后,禾谷缢管蚜成蚜的寿命分别为(8.60±0.22)、(8.03±0.18)和(6.68±0.18)d,均显著短于对照的(10.36±0.31)d;单雌产仔量分别为(21.88±0.63)、(20.41±0.53)和(16.68±0.35)只,也均显著少于对照的(26.40±0.89)只;产仔历期分别为(7.55±0.22)、(6.69±0.17)和(5.64±0.15)d,均显著短于对照的(9.13±0.31)d;试验浓度药剂处理对下一代若蚜期的影响不显著;LC30浓度处理对下一代成蚜繁殖有显著的抑制作用,可减少单雌产仔量3.74只,缩短产仔历期1.39 d。生命表参数分析表明:LC30浓度毒死蜱处理使小麦禾谷缢管蚜的净增殖率(R0)比对照降低了34.71%,使种群加倍时间(t)比对照延长了17.37%;LC20浓度处理使小麦禾谷缢管蚜的平均世代历期(T)延长了12.59%;LC10浓度处理组各项指标与对照间无显著性差异。研究表明,亚致死浓度毒死蜱能够缩短小麦禾谷缢管蚜成蚜的寿命,降低其繁殖力,该结果对小麦禾谷缢管蚜综合防治策略的制定具有积极意义。

In order to provide guidance for rational application of chlorpyrifos and understand the sublethal effects of chlorpyrifos on Rhopalosiphum padi（ Linnaeus）,sublethal concentration（ LC10,LC20 and LC30） of chlorpyrifos to adults of R. padi were determined by residual film in glass tube,and the sublethal effects on the grow th and reproduction of R. padi w ere evaluated. Results show ed thatafter being exposed to LC10,LC20 and LC30of chlorpyrifos,the longevity of R. padi adult w ere（ 8. 60 ± 0. 22）,（ 8. 03 ± 0. 18） and（ 6. 68 ± 0. 18） days,respectively,which were significantly shorter than that of the control（ 10. 36 ± 0. 31） days; the nymph number per aphid w ere（ 21. 88 ±0. 63）,（ 20. 41 ± 0. 53） and（ 16. 68 ± 0. 35）,respectively,w hich w ere significantly less than that of the control（ 26. 40 ± 0. 89）; the reproductive period w ere（ 7. 55 ± 0. 220）,（ 6. 69 ± 0. 17） and（ 5. 64 ± 0. 15） days,respectively,which were significantly shorter than that of the control（ 9. 13 ±0. 31） days. The duration of nymph of R. padi offspring w as not affected significantly w hen the adult w as exposed to sublethal concentration of chlorpyrifos. LC30 of chlorpyrifos could inhibit the offspring fecundity,the number of nymph per aphid decreased by 3. 74 and reproductive period shortened by1. 39 days as compared w ith that of the control. The demographic grow th parameters show ed that the net reproductive rate（ R0） of R. padi decreased by 34. 71% and population doubling time（ t） prolonged by 17. 37% after exposure to LC30 of chlorpyrifos; the mean generation time（ T） increased by 12. 59%after exposure to LC20 of chlorpyrifos; no significant difference w as observed betw een the parameters of LC10-treatment and control. The results that chlorpyrifos could reduce the longevity and reproduction of R. padi adult at sublethal concentration w ill be helpful in developing strategies for the IPM of R. padi.