Genetically modified (GM) crops have been developed worldwide through the recombinant DNA technology and commercialized by global agricultural companies. Until now, GM crops have not been cultivated commercially in Korea. Commercialization of GM crops requires a compulsory assessment of environmental risk associated with the release of GM crops. This study was conducted to evaluate the frequency of pollen mediated gene flow from Bt transgenic rice (Agb0101) to japonica non-GM rice (Nakdongbyeo), indica non-GM rice (IR36), and weedy rice (R55). A total of 729,917, 596,318 and 230,635 seeds were collected from Nakdongbyeo, IR36, and R55, respectively, which were planted around Agb0101. Selection of the hybrids was determined by repeated spraying of herbicide and Cry1Ac1 immunostrip assay. Finally, the hybrids were confirmed by PCR analysis using specific primer. The hybrids were found in all non-GM rice and out-crossing ranged from 0.0005% at IR36 to 0.0027% at Nakdongbyeo. All of hybrids were located within 1.2 m distance from the Agb0101 rice plot. The meteorological elements including rainfall and temperature during rice flowering time were found to be important factors to determine rice out-crossing rate. Consideration should be taken for many factors like the meteorological elements of field and physiological condition of crop to set up the safety management guideline to prevention of GM crops gene flow.

A variety of genetically modified (GM) crops have been developed in Korea. In these crops, the resveratrol-enriched transgenic rice plant (Agb0102) has moved ahead to generate the dossier for regulatory review process required for commercialization of GM crop. The resveratrol-enriched transgenic rice plant could be released to farmers for cultivation after national regulators have determined that it is safe for the environment and human health. Here, we developed a PCR-based DNA marker based on flanking sequences of transgene for the discrimination of resveratrol-enriched transgenic rice plant. This DNA markers will be useful for identifying of resveratrol-enriched transgenic rice plant, and can also be used to estimate transgene movement occurred by pollen transfer or seed distribution. Moreover, it is helpful for prompt screening of a homozygote-transgenic progeny in the breeding program.

In this study, we compared disease incidence rate and phyllosphere microbial community between drought resistance transgenic rice (Agb0103) and non-transgenic Ilmi (NGM) during 2011-2014 to examine an environmental risk assessment of drought resistance transgenic rice (Agb0103). As the results, major diseases such as sheath blight, brown spot, leaf blast and false smut were occurred, however, there were no significant disease incidence rate between Agb0103 and NGM. As the results of counting bacterial and fungal viable cell, the colonies were increased or decreased which affected by environmental conditions, however there were no differences between Agb0103 and NGM. Also unweighted pair-group method with arithmetic averaging (UPGMA) analysis based on polymerase chain reaction with denaturing gel electrophoresis (PCR-DGGE) revealed that DGGE band pattern of bacterial and fungal communities were clustered by each month and there were no differences between Agb0103 and NGM. Furthermore, isolated casual agents causing sheath blight and brown spot were collected from Agb0103 and NGM, and they revealed that each of pathogens were no differences in morphology and pathogenicity. Therefore, our results suggested that Agb0103 showed no differences in disease incidence rate, characteristic of pathogens and phyllosphere community with NGM. In this way, it can be assumed that transgenic rice Agb0103 could not influence phyllosphere microorganism community and environmental conditions.

The selectable marker-free rice plants containing mcry1Ac insecticidal gene isolated from Bacillus thuringiensis (Bt) were generated using a non-selection approach by Agrobacterium tumefaciens-mediated transformation. The nutritional composition of two lines of transgenic rice plants (RTB5 and RTB11) was compared with that of its non-transgenic counterpart. The results showed that, except for small differences in dietary fiber and some minerals, there was no significant difference between transgenic rice and conventional counterpart variety with respect to their nutrient composition. Most of measured levels of nutrients were within the range of values reported for other commercial cultivars, showing substantial equivalency. Therefore, the insertion of transgenes did not affect the nutritional composition of transgenic RTB5 and RTB11 rice grains.

The β-carotene biofortified transgenic rice was developed by transforming rice cv. Nakdongbyeo with phytoene synthase (Psy) and carotene desaturase (Crt I) genes isolated from Capsicum and Pantoea. The aim of this study was to perform molecular characterization of rice transformants of T5-T7 generation harboring Psy and Ctr I genes driven by endosperm specific globulin promoter for biosafety evaluation of β-carotene biofortified transgenic rice. The structure and sequence of T-DNA in the transformation vector and the insertion sites, flanking sequences and generational stability of inserted T-DNA in transgenic rice lines were analyzed. The transformation vector consisted of right border, MAR gene, carotenogenic genes unit, herbicide resistance selectable marker unit, MAR gene and left border in sequential order. T-DNA was introduced at the position of 30,363,938-30,363,973 bp of chromosome No. 2 by adaptor-ligation PCR. Stable integration of T-DNA and stable expression of bar gene was confirmed in T5 to T7 generations. It was also confirmed that the backbone DNA of transformation vector containing antibacterial gene was not present in the genome of β-carotene biofortified transgenic rice. HPLC analysis confirmed that carotenoids were consistently detected through T5-T7 generations.

Content of key nutrients and anti-nutrients of the insect-resistant transgenic rice (Btt12R) developed in Korea that contains a cryIIIA insecticidal gene was compared with those of its non-transgenic counterpart (Oryza sative L. cv. Nakdongbyeo). Grains of Btt12R, its parent cultivar, and two commercial rice plants (cv. Yeonganbyeo and Hwaseongbyeo) grown in the adjoining fields under the same environmental conditions and field management were used for this study. Among the analyzed 47 nutrients (8 proximates, 17 amino acids, 8 fatty acids, 9 minerals, and 5 vitamins) and two anti-nutrients (trypsin inhibitors and phytic acid), although the levels of 17 components differed between Nakdongbyeo and Btt12R, all of the measured values from Btt12R were within the ranges of values observed in the two typical Korean varieties and commercial rice provided by the OECD. These results confirm that the nutritional quality of rice grains was not affected by the insertion of the cryIIIA gene.

This study was carried out to develop of macro-protocol and the biosafety guide for drought-tolerant transgenic rice (Agb0103) at large scale GMO field, a total of 4,700 m². In GMO quarantine area of Kyungpook National University, insect species diversities and population densities on Agb0103 and wild type (Ilmi) were investigated. There was no difference between the population densities of insect pests and natural enemies on two varieties, while sometimes insect pest density on Ilmi was slightly higher than on Agb0103, but natural enemy density on Agb0103 was a little higher. These results provided the insect diversity for risk assessment analysis of Agb0103 and suggested that the macro-protocol could be useful to detect GM plants.