转植酸酶基因玉米对步甲群落动态的影响

Effect of phytase transgenic maize on the community dynamics of carabid beetles (Coleoptera:Carabidae)

本研究以陷阱法研究转植酸酶基因玉米及其亲本玉米在整个生长季节对地表步甲类群的影响。每个玉米品系设置6块样地,两个玉米品系交替排列,每个样地设置2个采样点,共设置24个样点,整个玉米生育期取样8次。本研究共采集步甲标本8012头,隶属于11属23种,其中黄斑青步甲Chlaenius micans个体数量分别占个体总数的87.54%,为玉米田内的主要常见物种,蠋步甲Dolichus halensis、后斑青步甲Chlaenius posticalis和单齿蝼步甲Scarites terricola个体数量分别占除黄斑青步甲之外所有步甲个体总数的34.77%,31.16%和6.21%,这些物种组成当地玉米田内的常见物种。步甲物种多样性与常见物种个体数量随季节变化明显,且转植酸酶基因玉米与其亲本玉米田内步甲物种多样性和常见物种个体数量的季节变化趋势相似度较高。重复测量方差分析(RepeatedANOVA)结果表明,转植酸酶基因玉米对步甲物种丰富度、物种多度、香农威纳多样性指数和均匀度指数均没有显著影响;转植酸酶基因玉米田内的后斑青步甲个体数量明显增加,但其他常见物种没有显著变化。基于非度量多维度(NMDS)的群落结构分析表明转植酸酶基因玉米与亲本玉米田内的步甲群落结构非常相似。本文结果表明转植酸酶基因玉米的种植对步甲物种多样性及常见物种没有明显影响。

We compared the phytase transgenic maize and its isogenic maize to examine the effect of phytase transgenic maize on the carabid beetles in the growing seasons （June to September） of 2012. Using the pitfall traps, beetles were collected from 12 plots along six replicated blocks for each maize. Each block was composed of two plots which were planted with phytase transgenic maize and its isogenic maize, respectively. Two sample locations with five traps for each location were set in each plot, and traps were emptied twice each month. A total of 8 012 specimens were collected, belonging to 7 genera and 23 species. Chlaenius micans represented 87.54% of the total capture and was the most abundant species. Dolichus halensis, Chlaenius posticalis and Scarites terricola occupied 34.77%, 31.16% and 6.21% of the total specimens, respectively, when the individuals of C. micans were excluded, and were also considered as common species in this study. Most carabid beetles showed a similar pattern in seasonal changes in phytase transgenic maize. There were no significant differences in richness, abundance, Shannon-Winner diversity index and evenness index of carabid beetles between phytase transgenic maize and its isogenic maize. Repeated ANOVA analysis showed that C. posticalis had significantly higher abundance in phytase transgenic maize compared with its isogenic maize, but other abundant species did not show significant differences between the two maize fields. Multivariate analysis （NMDS） also indicated that high similarity in carabid assemblages were shared between phytase transgenic maize and its isogenic maize. These results suggest that phytase transgenic maize has no significantly adverse effect on carabid beetles.