转cry1Ac基因抗虫玉米叶片残体降解对土壤动物群落结构的影响
Effects of leaf residue decomposition of cry1Ac-transgenic insect-resistant maize on community structure of soil animals

为研究转cry1Ac基因抗虫玉米Bt-799老熟叶片降解过程中对土壤动物群落结构的影响,采用凋落物分解袋法,调查了Bt-799及其对应的非转基因对照郑58和当地主栽常规品种郑单958共3个品种(系)玉米田自然条件下的土壤动物群落组成、类群丰富度和个体数,比较分析了土壤动物群落各特征参数。结果显示,共采集土壤动物42540头,隶属6纲11目,其中Bt-799田7481头,隶属4纲8目,郑58田8994头,隶属5纲8目,郑单958田26062头,隶属6纲8目,3个品种(系)在土壤动物群落组成上除少数稀有类群存在差异外,其优势类群均为蜱螨目和弹尾纲。Bt-799及其对照郑58的田间土壤动物类群丰富度、多度、Pielou均匀度指数、Simpson优势度指数、Shannon-Wiener多样性指数分别是3.49、138.54、0.50、0.33、0.76和3.30、166.56、0.46、0.29、0.73,均显著差异,郑单958田间土壤动物群落各特征参数则分别是2.67、489.46、0.47、0.30、0.68,与Bt-799及其对照郑58相比只有类群丰富度和多度存在显著差异,其它特征参数均显著差异。初步判定转基因玉米Bt-799叶片残体降解不会对土壤动物群落结构造成影响。
To study the effect of aging leaf decomposition of cry1Ac-transgenic insect-resistant maize (Bt-799) on community structure of soil animals, the litterbag method was used. Three varieties (lines) of maize, including cry1Ac-transgenic insect-resistant maize line (Bt-799), non-GM maize line Zheng 58 and the local major line Zhengdan 958 were studied. The soil fauna richness and numbers of individuals under natural conditions were analyzed, and the characteristic parameters of soil animal communities were compared. The results showed that the individual number of soil animals collected in these maize fields was 42540 in total, belonging to six classes, 11 orders. Among them, the number of soil animals in the group Bt-799 was 7481, belonging to four classes, eight orders; the number of soil animals in the group Zheng 58 was 8994, belonging to five classes, eight orders, and the number in the group Zhengdan 958 was 26062, belonging to six classes, eight orders. Except the differences in a few rare species, the dominant species in the community structure of soil animals of the three maize varieties (lines) all belonged to Collembola and Acarina. The soil fauna richness, abundance, Pielou index, Simpson index and Shannon-Wiener index of the group Bt-799 and its control group Zheng 58 were 3.49, 138.54, 0.50, 0.33, 0.76 and 3.30, 166.56, 0.46, 0.29, 0.73, respectively, and there was no significant difference between the above parameters. However, the indexes of the group Zhengdan 958 were 2.67, 489.46, 0.47, 0.30, 0.68, which only showed significant differences from the other two groups in soil fauna richness and abundance, and the other characteristics of soil animal communities had no significant difference. Therefore, we can initially determine that leaf residue decomposition of transgenic maize Bt-799 will not affect the community structure of soil animals.