Abstract:

To further understand the effects of sublethal dosage of imidacloprid on the growth, development and population parameter of red and green morphs of pea aphid (Acyrthosiphon pisum Harris) (Hemiptera: Aphidiae), both color morphswere treated by imidacloprid of different concentrations in the laboratory using life table method, respectively. The results showed that the fecundities of red and green morphs treated by imidacloprid (LC₂₀, LC₁₀ and LC₅) were significantly lower than that of control (P<0.05). The mean longevities of both color morphs treated by imidacloprid (LC₂₀) were significantly lower than that of control (P<0.05). The minimum mean longevities and fecundities of red and green morph adults treated by imidacloprid (LC₂₀) were 16.82, 21.44 and 2.84, 3.60 d, respectively. However, mean longevity was no significant difference between color morphs treated by imidacloprid (LC₁₀ and LC₅) and control. The developmental durations of F₁ generations of both color morph adults treated by imidacloprid (LC₂₀) had no significant difference compared with that of control, while the mean longevities were significantly shorter than that of control (P<0.05) and the survival rates were higher than that treated by imidacloprid (LC₁₀). The average fecundities of F₁ generations of both red and green morphs treated by imidacloprid (LC₁₀) reached the maximum values of 81.95 and 72.27. The reproductive peaks of F₁ generations differed between both color morphs, the reproductive peak of green morph was 3 to 7 d, and that of red morph was later than green morph. The population parameters of F₁ generations of red and green morphs treated by imidacloprid had no significant difference compared with that of control, whereas the net reproductive rates (R₀)(44.22) and mean generation times (T)(11.29) of F₁ generations of green morph treated by imidacloprid (LC₂₀) were significantly different compared with that of control (P<0.05). The study indicated that the mean longevities and fecundities of both red and green morph adults decreased and the red morph was more sensitive to different sublethal concentrations of imidacloprid than green morph, while the influences of imidacloprid on the F₁ generations of red and green morph were improved with the sublethal concentrations of imidacloprid increasing.

Key words: Imidacloprid, Sublethal effect, Color morph, Acyrthosiphon pisum Harris, Growth and development

摘要：

以不同亚致死剂量的吡虫啉分别处理2种色型豌豆蚜，采用实验种群生命表的方法，测定了不同亚致死剂量的吡虫啉处理2种色型豌豆蚜后其F₀及F₁代生长发育和种群参数的变化。结果表明：经处理的2种色型成蚜后，其平均产蚜量均显著低于同色组对照（P<0.05），平均寿命表现为LC₂₀处理后均显著短于同色组对照（P<0.05），而LC₁₀和LC₅处理后平均寿命与对照无显著差异，LC₂₀处理后红、绿色型成蚜的平均产蚜量（16.82和 21.44头）和平均寿命（2.84 d，3.60 d）均达到最小值；LC₂₀处理2种色型成蚜后，F₁代若虫期与同色组对照差异不显著，而成虫寿命显著短于同色组对照（P<0.05），若蚜存活率均高于LC₁₀处理，LC₅处理后F₁代红、绿色型豌豆蚜平均繁殖力均达到最大值81.95头和72.27头；不同亚致死剂量处理后F₁代2种色型成虫产蚜高峰期也存在差异，绿色型均集中在3～7 d，而红色型产蚜高峰期均晚于绿色型；除LC₂₀处理后F₁代绿色型豌豆蚜净增殖率（R₀）（44.22），平均世代周期（T）（11.29）与同色组对照差异显著外，2种色型豌豆蚜的其余参数在LC₂₀，LC₁₀和LC₅处理下均与同色组对照差异不显著。表明吡虫啉不同亚致死剂量处理2种色型成蚜后，对其F₀代寿命和繁殖力均起到抑制作用，且红色型较绿色型敏感，但对F₁代影响表现为高浓度较低浓度显著。

关键词: 吡虫啉, 亚致死效应, 色型, 豌豆蚜, 生长发育