College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou, Zhejiang, China.
Beijing Key Laboratory of Environment Friendly Management on Fruit Diseases and Pests in North China, Institute of Plant and Environment Protection, Beijing Academy of Agriculture and Forestry Sciences, Beijing, China.
Chemosphere. 2020 Nov;259:127497. doi: 10.1016/j.chemosphere.2020.127497. Epub 2020 Jun 30.
Heavy metal pollution is an increasingly serious problem in agricultural ecosystems. Zinc accumulation in the food chain may harm the physiological functions of organisms, including herbivorous and predatory insects. Its effects on development and reproduction in Harmonia axyridis are largely unknown. In this study, five Zn solutions (25, 50, 100, and 150 mg/kg) plus control (0 mg/kg) were used to treat broad beans and to water the resulting seedlings. Aphids fed on these seedlings were eaten by H. axyridis ladybugs. Zn accumulation was found at all three trophic levels. Compared with the control group, ladybugs in the 25, 50, and 100 mg/kg groups had significantly reduced weight gain from the 4 instar to adulthood. Pupae and larvae (instars 1-4) in the 150 mg/kg group had the lowest survival of any group; pupal mortality in the 100 mg/kg group was significantly higher than that in the control group. Under Zn stress, female adults had inhibited expression of Vg1, Vg2 and VgR, reducing egg production and hatchability. Zn thus negatively affected their fertility. These results provide a theoretical basis for future exploration of soil heavy metal pollution impacts in ecosystems.
重金属污染是农业生态系统中一个日益严重的问题。食物链中的锌积累可能会损害包括草食性和肉食性昆虫在内的生物体的生理功能。其对异色瓢虫发育和繁殖的影响在很大程度上尚不清楚。在本研究中，使用了五种 Zn 溶液（25、50、100 和 150mg/kg）加对照（0mg/kg）处理蚕豆，并浇灌由此产生的幼苗。取食这些幼苗的蚜虫被异色瓢虫捕食。在所有三个营养级都发现了 Zn 积累。与对照组相比，25、50 和 100mg/kg 组的成虫从 4 龄到成虫期体重增加明显减少。150mg/kg 组的蛹和幼虫（1-4 龄）存活率是所有组中最低的；100mg/kg 组的蛹死亡率显著高于对照组。在 Zn 胁迫下，雌性成虫抑制了 Vg1、Vg2 和 VgR 的表达，从而降低了产卵量和孵化率。因此，Zn 对它们的繁殖力有负面影响。这些结果为未来探索土壤重金属污染对生态系统的影响提供了理论依据。
