有机磷杀虫剂——灭克磷对丛枝菌根真菌Glomus mosseae生长的效应

采用多室隔网培养法,在宿主植物生长状况相同的条件下研究了土壤中不同浓度灭克磷对AM真菌生长的直接效应。与对照相比,0.5、1.5和3.5mg/kg灭克磷使Glomusmosseae菌丝生长量和具有琥珀酸脱氢酶活性的菌丝生长量明显地增加;随着灭克磷剂量的增加,菌丝总量的相对生长速率呈降低趋势,但在数值上仍然高于对照的;与此同时,高剂量(1.5和3.5mg/kg)灭克磷使Glomusmosseae活性菌丝量的相对增长速率明显低于对照,达到几乎停止的水平。上述结果说明,低剂量灭克磷(0.5mg/kg)对AM真菌生长和代谢活性都有一定刺激作用,但是在高剂量灭克磷(1.5和3.5mg/kg)下菌丝生物量的增加和周转速度的加快只是AM真菌对毒物的应激反应。

The impact of ethoprophos, an organic-pesticide, on arbuscular mycorrhizal fungus

We used a newly developed compartmented growth-system to investigate the effect of ethoprophos,a phosphorus containing pesticide, on the growth of AM fungus under the same host-growing condition. Comparing to control, addition of 0.5, 1.5 and 3.5 mg/kg ethoprophos increased the total hyphal length and the hyphal length with succinate dehydrogenase activity of Glomus mosseae significantly. With increasing of ethoprophos concentrations in soil, the relative growth rates of total hyphae were slowly decreased, but the values were still higher than those of control; however, the relative growth rates of hyphae with succinate dehydrogenase activity were lower than those of control and became almost zero under the higher doses of ethoprophos (1.5 and 3.5 mg/kg). It is concluded that low dose of ethoprophos (0.5 mg/kg) stimulated the growth and metabolic activity of AM fungus, and the increase of mycelium biomass and acceleration of turnover under high dose of ethoprophos (1.5 and 3.5 mg/kg) might be attributed to an emergency responding to the toxicity stress.