基改香蕉生物安全評估：對根圈土壤微生物相之影響

Biosafety Assessment of GM Banana: The Effect on Microflora Community in Rrhizosphere Soil

陳涵葳(Han-Wei Chen) ； 陳敬文(Jing-Wen Chen) ； 曾清山(Ching-Shan Tseng) ； 吳明哲(Min-Tze Wu) ； 杜元凱(Yuan-Kai Tu)

《台灣農業研究》 66卷2期 (2017/06) Pp. 134-145

https://doi.org/10.6156/JTAR/2017.06602.06

摘要

基因改造作物可能對環境造成未知的風險，本研究利用平板計數法、微生物群落層級生理譜 (community-level physiological profiles; CLPP) 等方法評估pflp (plant ferredoxin like protein) 香蕉轉殖系對根圈土壤微生物相之影響。試驗結果顯示，部分pflp 轉殖系定植1 mo 後，根圈土壤樣品之游離固氮菌及硝化細菌族群數目分別降低至5.84-6.44 (log_(10) CFU g^(-1)) 及5.38-5.96 (log_(10) CFU g^(-1))，顯著低於未轉殖對照品系Gros Michel 之6.59及6.52 (log_(10) CFU g^(-1))，但定植3 yr 轉殖系與未轉殖對照品系之根圈土壤樣品中，纖維分解菌、尿素分解菌、游離固氮菌、硝化系菌和氨氧化菌族群數目均無顯著差異。本試驗共檢測2,052 個菌落，皆未檢測出有外源基因nptII 的水平轉移情形。將CLPP 參數進行主成分分析、群集分析以及生物多樣性分析，結果顯示轉殖系與未轉殖對照品系間根圈土壤微生物相無顯著差異，亦不會影響根圈土壤微生物群落多樣性及均勻度。

關鍵字

基改作物 ； 生物安全評估 ； 根圈 ； 微生物群落

並列摘要

The environmental impacts on genetically modified (GM) crops are still unknown. This study aimed to explore the potential risk of pflp (plant ferredoxin-like protein) transgenic banana lines on rhizosphere microbial community and to investigate whether the gene flow occurs through horizontal gene transfer. The conventional plate counting method and the community-level physiological profiles (CLPP) method were used for evaluating rhizosphere microbial community. The results showed that most rhizosphere soil samples taken from pflp transgenic banana lines had reduced levels of Azotobacteria and nitrite oxidizing bacteria at respective 5.38-5.96 (log_(10) CFU g^(-1)) one month after transplanting. However, no significant difference was found in the quantity of culturable microorganisms in rhizosphere soils 3 years after transplanting. In this study, 2,052 colonies were analyzed for horizontal gene transfer, but no nptII fragment was detected. Results of cluster analysis for CLPP showed no difference between transgenic banana lines and their non-transgenic counterparts in microflora community composition. In addition, no significant difference was observed in species diversity and evenness of rhizosphere microorganisms between GM and non-GM banana plants. We conclude that pflp transgenic banana lines may not affect the diversity of rhizosphere microflora community structure, but have slight effects on microbial community in rhizosphere during first few months after transplanting.

並列關鍵字

Genetic modified crops ； Biosafety assessment ； Rhizosphere ； Microflora community