抗草甘膦转基因大豆(RRS)在黑土生态系统种植的安全性研究

Biosafety of Roundup Ready Soybean(RRS) Planted in Black Soil Ecosystem

为明确抗草甘膦转基因大豆(RRS)在黑土生态系统种植的安全性,经过连续3年田间和盆栽试验,分析了抗草甘膦转基因漂移(漂流)可能性,及抗草甘膦转基因大豆(RRS)在黑土区对根际生态系统微生物数量,氮代谢和两种土壤酶活性的影响。结果表明:在自然条件下花粉漂移几乎是不可能的,但如人为加大虫媒传播(大于10头·m-2),抗草甘膦基因的漂移概率接近0.05%,漂移距离为0.7m。RRS除对根际真菌数影响不显著外,对根际土壤细菌、放线菌、氨化和硝化细菌均表现降低趋势。在大豆不同生育期,RRS除对根际土壤真菌数影响不显著外,对根际土壤细菌,放线菌,氨化和硝化细菌均表现降低趋势;RRS根际土壤细菌多样性指数与均匀度指数均低于亲本RRS-S;氨化强度与RRS-S相比差异不显著,RRS根际土壤硝化强度显著低于亲本RRS-S;RRS降低了过氧化氢酶和脲酶活性。

In the three-year field and pot experiments, this study investigates possibility of the CP4 -EPSPS gene flow of Roundup Ready Soybean（RRS） in black soil ecosystem,and impacts of RRS on numbers of its rhizosphere microorganisms, N-cycling and some enzymes in soil. According to the field experiments, the CP4 -EPSPS gene flow did not happen in natural condition,but under insects（ more than 10 insects per square meter） helping to pollen, the floating possibility of this gene was 0.05 % , and the floating distance was 0.7 meter. In different soybean growth stages ,in rhizosphere soil of RRS, the amount of bacteria, actinomycete, ammonifying bacteria, and nitrifying bacteria showed decreasing tendencies, except no effect on total number of fungus. The bacterial diversity indexes and homogeneous degrees indexes in rhizospheric soil of RRS were lower than that of its parent RRS- S. The difference of ammonification intensity was not significant in RRS and RRS-S rhizosphere soil,and nitrification intensity in RRS was significantly lower than that in RRS-S rhizosphere soil in different growth stages and RRS inhibited activities of catalase and urease.