Griffiths Bryan S, Heckmann Lars-Henrik, Caul Sandra, Thompson Jacqueline, Scrimgeour Charlie, Krogh Paul Henning
Environment Plant Interactions Programme, Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA, UK.
Plant Biotechnol J. 2007 Jan;5(1):60-8. doi: 10.1111/j.1467-7652.2006.00215.x.
A glasshouse experiment was undertaken to provide baseline data on the variation between conventional maize (Zea mays L.) varieties and genetically modified maize plants expressing the insecticidal Bacillus thuringiensis protein (Bt, Cry1Ab). The objective was to determine whether the variation in soil parameters under a range of conventional maize cultivars exceeded the differences between Bt and non-Bt maize cultivars. Variations in plant growth parameters (shoot and root biomass, percentage carbon, percentage nitrogen), Bt protein concentration in shoots, roots and soil, soil nematode abundance and soil microbial community structure were determined. Eight paired varieties (i.e. varieties genetically modified to express Bt protein and their near-isogenic control varieties) were investigated, together with a Bt variety for which no near-isogenic control was available (NX3622, a combined transformant expressing both Bt and herbicide tolerance) and a conventional barley (Hordeum vulgare L.) variety which was included as a positive control. The only plant parameter which showed a difference between Bt varieties and near-isogenic counterparts was the shoot carbon to nitrogen ratio; this was observed for only two of the eight varieties, and so was not attributable to the Bt trait. There were no detectable differences in the concentration of Bt protein in plant or soil with any of the Bt-expressing varieties. There were significant differences in the abundance of soil nematodes, but this was not related to the Bt trait. Differences in previously published soil nematode studies under Bt maize were smaller than these varietal effects. Soil microbial community structure, as determined by phospholipid fatty acid (PLFA) analysis, was strongly affected by plant growth stage but not by the Bt trait. The experimental addition of purified Cry1Ab protein to soil confirmed that, at ecologically relevant concentrations, there were no measurable effects on microbial community structure.
进行了一项温室试验，以提供关于常规玉米（Zea mays L.）品种与表达苏云金芽孢杆菌杀虫蛋白（Bt，Cry1Ab）的转基因玉米植株之间差异的基线数据。目的是确定一系列常规玉米品种下土壤参数的变化是否超过了Bt和非Bt玉米品种之间的差异。测定了植物生长参数（地上部和根部生物量、碳百分比、氮百分比）、地上部、根部和土壤中的Bt蛋白浓度、土壤线虫丰度和土壤微生物群落结构。研究了八对品种（即经基因改造以表达Bt蛋白的品种及其近等基因对照品种），以及一个没有近等基因对照的Bt品种（NX3622，一种同时表达Bt和除草剂耐受性的复合转化体）和一个作为阳性对照的常规大麦（Hordeum vulgare L.）品种。Bt品种与其近等基因对应品种之间唯一显示出差异的植物参数是地上部碳氮比；在八个品种中只有两个品种观察到了这种情况，因此这并非归因于Bt性状。在任何表达Bt的品种中，植物或土壤中Bt蛋白浓度均未检测到差异。土壤线虫丰度存在显著差异，但这与Bt性状无关。先前发表的关于Bt玉米下土壤线虫研究的差异小于这些品种效应。通过磷脂脂肪酸（PLFA）分析确定的土壤微生物群落结构受植物生长阶段的强烈影响，但不受Bt性状的影响。向土壤中实验性添加纯化的Cry1Ab蛋白证实，在生态相关浓度下，对微生物群落结构没有可测量的影响。
