淹水对Bt玉米秸秆地表覆盖还田条件下Bt蛋白降解的影响  

Impacts of Flooding on the Degradation of Bt Protein Released from Bt Corn Straws under Soil Surface

作　　者：范慧芝[1] 冯远娇[1] 王建武[1] 

机构地区：[1]华南农业大学热带亚热带生态研究所,广东广州510642

出　　处：《土壤通报》2010年第5期1077-1080,共4页Chinese Journal of Soil Science

基　　金：国家自然科学基金资助项目(30470335;30770402);广东省自然科学基金资助项目(E039254;06025813);广东省科技计划项目(2006B50104002;2007A020300009-1)资助

摘　　要：采用网袋法在室内模拟研究了Bt（Bacillus thuringiensis）玉米34B24和1246×1482秸秆地表覆盖还田淹水和非淹水条件下Bt蛋白的降解动态,并应用移动对数模型进行拟合及估算DT50和DT90,探讨淹水对Bt玉米秸秆地表覆盖下Bt蛋白降解过程的影响。结果表明：两品种秸秆中Bt蛋白在室内模拟地表覆盖淹水和非淹水条件下均能快速降解,降解动态均呈前期快速大量降解和中后期极低量稳定下降两个阶段,1周内两品种秸秆淹水和非淹水条件下Bt蛋白均已降解了90%以上,但到180 d时,还可检测到占初始含量0.009%~0.017%的Bt蛋白。Bt蛋白ELISA法实测数据和移动对数模型拟合得出的DT50和DT90均表明非淹水条件下Bt蛋白降解较慢,但淹水促进秸秆中Bt蛋白降解的作用仅表现在地表覆盖初期（第1 d）,其后影响不大。Impacts of flooding on the degradation dynamics of Bt protein released from Bt corn straws（34B24 and 1246×1482） under soil surface were investigated in laboratory using litterbag technique.Besides,DT50 and DT90 were also estimated according to the shift-log model proposed by Herman to explore the effects of flooding on the degradation process of Bt protein released from Bt corn straws under soil surface.The results showed that Bt protein released from the straws of Bt corns either under soil surface in flooded or non-flooded conditions could be degraded very fast.The degradation dynamics demonstrated a two-stage pattern,a rapid decline in the early stage and then stable at extremely low concentration in the middle and later stage.More than 90% of Bt protein from the straws of two Bt corn varieties was degraded under both flooded and non-flooded conditions within one week,but 0.009%-0.017% of the initial Bt protein amount could also be detected after the degradation of Bt corn straws for 180 days.The data from both ELISA and estimation of DT50 and DT90 indicated that Bt protein degraded relatively slower under non-flooded condition,but the accelerated effects of flooding on the degradation of Bt protein were only observed in the early stage（the first day） of the soil covering.

关 键 词：BT玉米 BT蛋白 淹水 地表覆盖 拟合模型 

分 类 号：X705[环境科学与工程—环境工程]