三种杀线虫剂对甘薯茎线虫扩散的Hormesis效应

在实验室条件下应用沙柱法及水琼脂平板法,测定了低剂量水平的涕灭威、甲氨基阿维菌素苯甲酸盐和丙溴磷对甘薯茎线虫Ditylenchus destructor扩散行为的影响。结果表明:在含5 μ g/mL 药剂的沙柱中,以及甘薯茎线虫经0.1 μ g/mL的药剂浸渍24 h后在不含药剂的沙柱中,其运动扩散能力均受到抑制;在含较低质量浓度(5×10－3 μ g/mL)药剂的沙柱中,以及线虫经较低质量浓度(10－2,10－3 μ g/mL)的涕灭威和(10－4,10－5 μ g/mL)甲氨基阿维菌素苯甲酸盐浸渍24 h后在不含药剂的沙柱中,其通过率均比空白对照高10%以上,差异显著,表现出Hormesis效应(兴奋效应);经较低质量浓度(10-1 μ g/mL)的丙溴磷浸渍后在不含药剂的沙柱中未表现出该效应。在水琼脂平板试验中,虽然在低剂量水平下药剂对线虫的扩散具有促进作用,但产生的Hormesis效应不如沙柱法的结果明显。

Hormesis effect of three nematicides on the dispersal of Ditylenchus destructor

Effects of low-dose aldicarb,emamectin benzoate and profenofos on the dispersal activity of Ditylenchus destructor were tested by using sand columns and water agar plate.The results showed that the movement of nematodes was adversely affected at the highest concentration of nematicides (5 μ g/mL nematicides solution in sand columns and 0.1 μ g/mL nematicides solution which was used to dip nematodes for 24 h),while the percentage of nematodes that moved through sand columns was increased by more than 10%(P－3 μ g/mL nematicides solution in sand columns and 10－2 ,10－3 μ g/mL aldicarb,10－4 ,10－5 μ g/mL emamectin benzoate solution which was used to dip nematodes for 24 h),which was a Hormesis phenomenon.The hormetic effect of nematodes that had treated by low-concentration of profenofos (10-1 μ g/mL) was not observed.In water agar plate bioassay,low-dose nematicides could promote the dispersal of nematodes,but the hormetic effects were less than that in sand column assay.