The Effects Of Transgenic Bt Rice On The Community Structure And Biodiversity Of Endophytes

A genetically modified organism (GMO) is any organism whose genetic material has been altered using genetic engineering techniques. Recent two decades, more and more GMO crops have been introduced, and cultivated. Meanwhile, scientists and consumer paid more attention toward the evnironmnet biosafety concerns. An endophyte is an endosymbiont, often a bacterium or fungus that lives within a plant for at least part of its life without causing apparent disease. Endophytes are ubiquitous and have been found in all the species of plants studied to date; however, most of these endophyte/plant relationships are not well understood. GMO rice and its influence on endobacteria biodiverisity and claded structure is an important topic of GMO rice biosafety. In this study, we compared the endobacteria in GMO rice (transformation Bt protein, TT51) and its wild type parental cultivar (MH63) difference growth stages (seedling stage, tillering stage, flowering stage and fruiting stage). Followed isolation and identification of endobacteria, we also addressed those cultivable endobacertia whether they have Bt gene horizontal transfer.1:GMO rice influence on cultivable endobacteria biodiversity. Endobacteria (1193isolates) from four different growth stages of GMO rice HH51and wild type MH63were isolated and identified. We identified664isolates from GMO rice and529isolates from wild type rice.16S rDNA sequences revealed that those endobacteria isolated from GMO rice was belonging to4Phylum,16Class,41genuses, and92species; while those endobacteria isolated from wild type rice were belong to55genus and99species. The number of species in different growth stages was also varied. Furthermore the species of endobacteria was difference between GMO rice and its wild type rice.2:Rice endobacteria isolated from both GMO rice and Non-GMO rice in this study showed great diversity. Regardless the difference of GMO and Non-GMO, rice endobacteria diversity increased from seedling stage and reach diversity peak at tillering stage, and gradually decreased at flowering and increase again at fruiting stage. At each growth stage, the difference of endobacteria diversity isolated from GMO rice and non-GMO rice is significant. Our date suggested the relative lower diversity in GMO rice at seedling stage, tillering stage, and flowering stage, but higher in fruiting stage comparing to non-GMO rice.3:Our data did not find positive Bt gene horizontal transformation from GMO rice to endobacteria. PCR result from all the664endobacteria from GMO rice show negative PCR products, suggested extremely low gene transfer efficiency.