Kreutzweiser David, Good Kevin, Chartrand Derek, Scarr Taylor, Thompson Dean
Canadian Forest Service, Natural Resources Canada, 1219 Queen St. East, Sault Ste. Marie, Ontario, Canada, P6A 2E5.
Ecotoxicol Environ Saf. 2007 Nov;68(3):315-25. doi: 10.1016/j.ecoenv.2007.04.011. Epub 2007 May 23.
Imidacloprid is effective against emerald ash borer when applied as a systemic insecticide. Following stem or soil injections to trees in riparian areas, imidacloprid residues could be indirectly introduced to aquatic systems via leaf fall or leaching. Either route of exposure may affect non-target, aquatic decomposer organisms. Leaves from ash trees treated with imidacloprid at two field rates and an intentionally-high concentration were added to aquatic microcosms. Leaves from trees treated at the two field rates contained imidacloprid concentrations of 0.8-1.3 ppm, and did not significantly affect leaf-shredding insect survival, microbial respiration or microbial decomposition rates. Insect feeding rates were significantly inhibited at foliar concentrations of 1.3 ppm but not at 0.8 ppm. Leaves from intentionally high-dose trees contained concentrations of about 80 ppm, and resulted in 89-91% mortality of leaf-shredding insects, but no adverse effects on microbial respiration and decomposition rates. Imidacloprid applied directly to aquatic microcosms to simulate leaching from soils was at least 10 times more toxic to aquatic insects than the foliar concentrations, with high mortality at 0.13 ppm and significant feeding inhibition at 0.012 ppm.
吡虫啉作为一种内吸性杀虫剂，对翡翠灰螟有效。在河岸地区对树木进行树干注射或土壤注射后，吡虫啉残留可能通过落叶或淋溶间接进入水生系统。这两种暴露途径都可能影响非目标水生分解生物。将以两种田间施用量和一个故意设定的高浓度处理过的灰树树叶添加到水生微宇宙中。以两种田间施用量处理过的树木的树叶中吡虫啉浓度为0.8 - 1.3 ppm，对碎叶昆虫的存活、微生物呼吸或微生物分解速率没有显著影响。当叶面浓度为1.3 ppm时，昆虫取食率受到显著抑制，但在0.8 ppm时未受抑制。故意高剂量处理的树木的树叶中浓度约为80 ppm，导致碎叶昆虫死亡率达89 - 91%，但对微生物呼吸和分解速率没有不利影响。直接施用于水生微宇宙以模拟从土壤中淋溶的吡虫啉对水生昆虫的毒性比对叶面浓度至少高10倍，在0.13 ppm时死亡率很高，在0.012 ppm时取食受到显著抑制。
