Team:TzuChiU Formosa/Humanpractice/review

A review written by Dr. Chen Chun-Yao

Prof. Chun-Yao Chen

PhD in Comparative Biology
Cornell University, USA

Associate Professor
Department of Life Sciences
Tzu Chi University, Hualien, Taiwan
Field : Bacteriology, Microbiology, Ecology

Is genetically modified crop (GMC) ecologically safe? More research is needed.
Chun-Yao Chen, Department of Life Science, Tzu-Chi University

This issue can be examined at four levels.


1. Will the GMC survive and outcompete local plants?
These crop species are generally less fit in the environments when compared with the indigenous species, therefore we probably spare ourselves from worrying about their direct impact on local community.


2. Will the indigenous plant species acquire the transgene?
It is widely accepted that genes can be transferred from crops to their wild relatives[1]. The resulting hybridization, if followed by polyploidization, can stabilize and keep the gene in the population. Changes in relative fitness of this genetic transfer and the potential ecological consequences, as well as how to streamline decision-making processes for transgenes that could cause unwanted ecological change, has becoming an emerging focus of research [2].


3. Will the transgenic plants affect the insect community?
The strategic use of transgene, for example Cry toxins from Bacillus thuringiensis (Bt), to help the crop ward off insect pest has been successful. The use of Bt crops results in significant reductions of insecticide use, which is beneficial to the environment [3]. However, they also found changes in insect community composition, in that abundance of some beneficial insects increased. More research effort is needed to clarify and calculate the risk.


4. Will the transgene affects the plant-microbe interaction?
Highly diversified microbiota can be seen in plant rhizosphere, and is known to be affected by root/plant physiology. A study has shown that cultivating Bt cotton did not adversely affect the soil microbiota [4]. However another study using genetically modified poplar detected changes in microbial composition [5]. GMC affected growth of arbuscular mycorrhizal fungi, and may affect fungal diversity after long-term cultivation [6]. Still, more research effort is needed to clarify and calculate the risk.

References
1.Raven PH. Does the use of transgenic plants diminish or promote biodiversity? N Biotechnol. 2010 Nov 30;27(5):528-33. Epub 2010 Aug 1. Review. PubMed PMID: 20678596.
2.Wilkinson M, Tepfer M. Fitness and beyond: preparing for the arrival of GM crops with ecologically important novel characters. Environ Biosafety Res. 2009 Jan-Mar;8(1):1-14. Epub 2009 May 7. PubMed PMID: 19419648.
3.Yu HL, Li YH, Wu KM. Risk assessment and ecological effects of transgenic Bacillus thuringiensis crops on non-target organisms. J Integr Plant Biol. 2011 Jul;53(7):520-38. doi: 10.1111/j.1744-7909.2011.01047.x. PubMed PMID: 21564541.
4.Kapur M, Bhatia R, Pandey G, Pandey J, Paul D, Jain RK. A case study for assessment of microbial community dynamics in genetically modified Bt cotton crop fields. Curr Microbiol. 2010 Aug;61(2):118-24. Epub 2010 Jan 23. PubMed PMID: 20098990.
5.Hur M, Kim Y, Song HR, Kim JM, Choi YI, Yi H. Effect of genetically modified poplars on soil microbial communities during the phytoremediation of waste mine tailings. Appl Environ Microbiol. 2011 Sep 2. [Epub ahead of print] PubMed PMID: 21890678.
6.Liu W. Do genetically modified plants impact arbuscular mycorrhizal fungi? Ecotoxicology. 2010 Feb;19(2):229-38. Epub 2009 Oct 6. PubMed PMID: 19806453.