富含硫氨基酸转基因大豆对根际土壤有机元素含量和微生物群落多样性的影响

Effects of Sulfur-rich Amino Acids Transgenic Soybeans on Soil Organic Elements and Microbial Community Diversity

为揭示种植富含硫氨基酸的转基因大豆对土壤生态系统的影响,在网室栽培条件下,测定了成熟期根际土的有机元素含量,并利用Biolog ECO/GN/GP/FF系统分析了种植转基因大豆(A组:受体为南农88-1,3个转基因株系为OE-8,OE-7和RNAi-3;B组:受体为N2899,3个转基因株系为Gagal 17-4,Gagal 21-8和Gagal 57)对土壤微生物活性和群落功能多样性的影响。结果表明:种植2组转基因大豆后土壤硫元素与各自受体相比均极显著下降(P<0.01),A组中3个转基因大豆株系的每孔颜色平均变化率(Average well color development,AWCD)表征的土壤微生物活性和McIntosh等多样性指数均低于对照,其中,3个转基因大豆株系根际土革兰氏阴性菌的AWCD值极显著低于对照(P<0.01),革兰氏阳性菌的AWCD值和McIntosh指数均显著低于对照(P<0.05);转基因品系OE-8根际土真菌的McIntosh指数也极显著低于对照(P<0.01)。B组中转基因品系Gaga1 17-4和Gaga1 21-8的革兰氏阳性菌AWCD值显著高于对照,而Gagal 57的革兰氏阳性菌AWCD值显著低于对照(P<0.05)。转基因大豆根际土壤微生物在Bi-olog生态板上与对照组相比没有显著差异。因此,试验所用转基因大豆能够显著影响土壤革兰氏阴性菌和阳性菌的活性以及革兰氏阳性菌与真菌的群落多样性,且这种影响与受体品种的基因型有关。

In this study,the effects of sulfur-rich amino acids transgenic soybeans on soil organic elements and functional diversity of microbial community were investigated to reveal the safety of transgenic soybeans on soil ecology environment.Microorganism community of transgenic soybeans（Group A：three transgenic soybean lines OE-8,OE-7,RNAi-3 and their recipient Nannong 88-1;Group B：three transgenic soybean lines Gagal 17-4,Gagal 21-8,Gagal 57 and their recipient N2899）in mature stage were analyzed by Biolog ECO/GN/GP/FF systems.The results showed that sulfur contents in rhizosphere soil were significantly decreased in the soil of all transgenic soybean lines（P0.01）.There were also differences in activities,community diversities and richness of soil microbial between transgenic soybeans and non-transgenic soybeans.Two groups of soybeans showed different patterns because of their different recipient genotypes.In Group A,average well color developments（AWCDs）and McIntosh indexes of transgenic soybeans were lower than CK1,especially AWCDs of gram-negative bacteria,and AWCDs,McIntosh indexes of gram-positive bacteria.In rhizosphere soil of three transgenic soybeans,AWCDs of gram-negative bacteria were significantly lower than Nannong88-1（P0.01）,and McIntosh index of gram-positive bacteria were significantly lower than Nannong88-1（P0.05）.McIntosh index of fungi in rhizosphere soil of transgenic soybean OE-8 was significantly lower than Nannong88-1（P0.01）.In Group B,AWCDs of gram-positive bacteria of Gagal 17-4 and Gagal 21-8 were significantly higher than N2899,while AWCD of gram-positive bacteria of Gagal 57 was significantly lower than N2899（P0.05）.As for both groups,there were no significant differences in whole microorganisms when we compared AWCDs and indexes of community diversity in Biolog ECO plates.These results suggested that transgenic soybeans in our study could change activities of gram-negative and gram-positive bacteria,community diversities of gram-positive bacteria and fungi,and at the same time depended on the genotypes of recipients.