中文摘要：

在大棚水泥池内种植两个Bt玉米（5422Bt1和5422CBCL）及其同源常规玉米5422,研究了种植Bt玉米及秸秆还田过程中根际土、根围土、3层根外土（0~20、20~40和40~60cm）中Bt蛋白含量的时空动态特征及其对土壤养分含量的影响.结果表明：种植Bt玉米和常规玉米后,根围土（种植后90 d）和3层根外土（种植后30、60和90 d）中均检测到少量的Bt蛋白（含量〈0.5 ng·g-1）,在Bt玉米5422Bt1和5422CBCL根际土中则分别检测到1.59和2.78 ng·g-1的Bt蛋白.玉米秸秆还田后,Bt蛋白能在3 d内快速降解,在还田后第7天只检测到少量的Bt蛋白.与常规玉米5422相比,种植Bt玉米5422Bt1 90 d后根围土和3层根外土中有机质、速效养分（碱解氮、速效磷和速效钾）和全量养分（全氮、全磷和全钾）含量均没有显著差异;5422Bt1秸秆还田60 d后0~20 cm土层的有机质和全氮含量显著升高,速效钾含量显著降低,而其他养分指标则没有显著差异,20~40 cm和40~60 cm土层的所有养分指标均没有明显差异.种植Bt玉米5422CBCL后根围土中仅速效磷含量显著低于种植常规玉米5422,但0~20 cm土层中全磷含量显著提高,其他养分指标均没有差异;还田5422CBCL秸秆后仅0~20 cm土层的速效磷含量显著高于常规玉米5422.研究结果表明,通过玉米根系分泌和秸秆分解进入土壤的Bt蛋白不会在土壤中累积,对养分含量也基本没有显著影响.

英文摘要：

The spatiotemporal dynamics of Bt protein in soil and the change of soil nutrients in rhi- zosphere soil, root surface soil and soils at 0-20, 20-40 and 40-60 cm were measured in green- house experiments. Two Bt corns, 5422Btl and 5422CBCL, and their near isogenic non-Bt variety 5422 were grown for 90 days and the crop residues were retained to soil. Results showed that 1.59 and 2.78 ng . g-1 Bt protein were detected in the rhizosphere soil with Bt corns 5422Btl and 5422CBCL immediately after harvest. However, there were only trace amounts of Bt protein （〈0.5 ng g-l） were detected in root surface soil after 90 days and in bulk soil in the two Bt corn treat- ments after 30, 60 and 90 days. When corn residues returned to soil, Bt protein declined rapidly within 3 clays and only trace amounts of Bt protein were measured after 7 days. There were no significant differences in organic matter, available nutrient （ alkaline hydrolytic N, available P, availa- ble K） or total nutrient （total N, total P, total K） in root surface soils and soils at 0-20 cm, 20- 40 cm and 40-60 cm among the Bt and non-Bt corns after 90 days. Sixty days after returning crop residues of 5422Btl to soil, the contents of organic matter and total N increased and the content of available K reduced significantly in the 0-20 cm soil depth. There were no significant differences in any other parameter at the 0-20 cm depth, neither for any parameter in the 20-40 cm and 40-60 cm soil depths compared to those in the non-Bt corn 5422 treatment. There were no significant differences in soil nutrient contents in Bt corn 5422CBCL treatment compared to those in non-Bt corn 5422 treatment except that available phosphorus content was reduced in root surface soils, and total P content increased at the 0-20 cm soil depth after 90 days. When crop residues of Bt corn 5422 CBCL were returned to soil, only available P higher compared to the soil receiving crop residues content in the 0-20 cm soil layer was evidently of non-Bt corn 5422. Results suggeste