磺胺间甲氧嘧啶在玉米根-土界面毒性研究

通过根际袋土培试验,研究了磺胺间甲氧嘧啶（SMM）对玉米根际与非根际土壤酶活性和土壤呼吸强度的影响。结果表明,无论是否有根系作用,过氧化氢酶对磺胺间甲氧嘧啶胁迫的反应均不敏感。但在高浓度磺胺间甲氧嘧啶（50 mg.kg-1）作用下,试验初期对脲酶有明显的抑制作用,而在试验后期则表现出一定的促进作用,且在SMM胁迫下根际效应表现得更为明显。SMM胁迫下对根际与非根际土壤呼吸均有抑制作用,随浓度的增大,抑制作用越明显。且由于玉米根际作用,一定程度上缓解了SMM污染对根际微生物的毒害。一般情况下,根际土壤脲酶和过氧化氢酶活性及土壤呼吸强度均要大于非根际土壤,根际效应明显。

The Eco-toxicological Effect of Sulfamonomethoxine on Corn Rhizospheric and Non-rhizospheric Soil

The effects of sulfamonomethoxine（SMM）on soil respiration and activities of urease and catalase in corn rhizosphere and non-rhi-zosphere were investigated by using a rhizobox simulating rhizosphere environment.The study showed that SMM had not significantly effect on the catalase activity during the most incubation period whether it effected by corn root or not.The activity of soil urease was inhibited at the beginning but stimulated afterwards in high dosage concentration of SMM（50 mg.kg-1）.The urease activities of rhizosphere soil polluted by SMM were higher than the control,and had a significant rhizosphere effects.Soil respiration was inhibited by SMM both in corn rhizo-spheric and non-rhizospheric soil,the higher of treated concentration of SMM,the stronger inhibition of soil respiration suffered.SMM was less poisonous to soil respiration with the effect of corn rhizospheric.Meantime,the enzyme activities and soil respiration in rhizospheric soil were higher than that of non-rhizosphere all along,the rhizosphere effect was significant.