‘Jungmo2501’ (Avena sativa L.), a winter oat for forage use, was developed by the breeding team at the National Institute of Crop Science, RDA in 2010. The following is the characteristics of ‘Jungmo2501’ that is characterized as light green leaf, yellow brown culm and whitish yellow grain. The heading date of ‘Jungmo2501’ was about 3 days earlier than that of check cultivar ‘Samhan’(May 7 and May 10, respectively). Its plant height was 11 cm longer than 103 cm of the check, and the leaf blade ratio of aerial parts was 26 % higher than the check (11.8% and 9.4%, respectively). The cold tolerance, resistance to lodging and wet injury of ‘Jungmo2501’ were similar to those of the check. The average forage dry matter yield of ‘Jungmo2501’ harvested at milk-ripe stage was 5% higher than the check (15.5 ton ha -1 and 14.7 ton ha -1 , respectively). ‘Jungmo2501’ was higher than the check in terms of protein content (6.6% and 5.9%, respectively), neutral detergent fiber (58.5% and 57.6%, respectively), and acid detergent fiber (34.5% and 32.1%, respectively), while total digestible nutrients was lower than the check (61.6% and 63.6%, respectively), and TDN yield was 0.37 ton ha -1 more than that of the check (9.71 ton ha -1 and 9.34 ton ha -1 , respectively). The silage grade of ‘Jungmo2501’ estimated by Flig score showed level Ⅱ, meaning good quality. Fall sowing cropping of ‘Jungmo2501’ is recommended only for areas where average daily minimum mean temperatures in January are higher than －6°C.

The β-carotene biofortified transgenic soybean was developed recently through Agrobacterium-mediated transformation using the recombinant PAC (Phytoene synthase-2A-Carotene desaturase) gene in Korean soybean (Glycine max L. cv. Kwangan). GM crops prior to use as food or release into the environment required risk assessments to environment and human health in Korea. Generally, transgenic plants containing a copy of T-DNA were used for stable expression of desirable trait gene in risk assessments. Also, information about integration site of T-DNA can be used to test the hypothesis that the inserted DNA does not trigger production of unintended transgenic proteins, or disrupt plant genes, which may cause the transgenic crop to be harmful. As these reasons, we selected four transgenic soybean lines expressing carotenoid biosynthesis genes with a copy of T-DNA by using Southern blot analysis, and analyzed the integration sites of their T-DNA by using flanking sequence analysis. The results showed that, T-DNA of three transgenic soybean lines (7-1-1-1, 9-1-2, 10-10-1) was inserted within intergenic region of the soybean chromosome, while T-DNA of a transgenic soybean line (10-19-1) located exon region of chromosome 13. This data of integration site and flanking sequences is useful for the biosafety assessment and for the identification of the β-carotene biofortified transgenic soybean.

In recent years, novel plant breeding techniques (NPBTs) have emerged, and safety assessment of the novel plant(s) generated using the NPBTs has drawn the attention of many stakeholders. The notable characteristics of the novel plants are as follows: firstly, it is almost impossible to distinguish from the natural mutations in the conventional counterparts, because site-directed nuclease (SDN) and oligonucleotide-directed mutagenesis (ODM) could introduce short indel(s) in the targeted region(s) of the chromosomes. Secondly, the genome constitution of novel plants is almost identical to that of their conventional counterparts, eventually becoming indistinguishable by the introduction of only unmodified gene(s) from sexually compatible species to the target host plant. Thirdly, it is possible to generate new plants that have the desired traits, but without introducing genes. These plants will have some modified bases in their genome by selecting null-segregant(s) from heterozygous transgenic plants or by other epigenetic methods. The Organisation for Economic Co-operation and Development (OECD) and many countries developing genetically modified organisms (GMOs) have concluded that novel plants developed using SDN, ODM, cisgenesis, intragenesis, or null-segregant techniques are treated in the same manner as non-genetically modified (GM) plants or may even have less strict risk assessments depending on the case. Additionally, grafting and agro-infiltration are methods that can be used to avoid or reduce the burden of current strict GMO risk assessment. The risk assessments of some of the novel plants have already been performed and those of commercially important plants are expected to be performed in the near future. Hence, it is necessary to develop a competitive and practical NPBT that can mitigate the concern and revulsion toward GMOs in Korea.

The purpose of this study was to characterize the T-DNAs introduced into the transgenic OsCK rice, as part of a biosafety evaluation. Choline Kinase (CK) gene is upregulated in the transgenic OsCK rice. We identified the insertion sites, flanking sequences, structures and sequences of the inserted T-DNAs. Based on the adaptor-ligation PCR, we found that the right border of the T-DNA was inserted at position no. 129971, on BAC clone OSJNBa0014J14 of chromosome 10. The flanking sequences of the left border region of the T-DNA (which was later identified as a region harboring a 1-kb long deleted sequence), could not be identified by various PCR-based trials. However, it was finally identified with whole-genome shotgun sequencing, using an Illumina sequencer. The result indicated that one of the T-DNAs was inserted into the CaMV 35S promoter region, whereas the other T-DNA was introduced at position 128947 on OSJNBa0014J14 clone, with an inverse orientation. During the insertion process, a 1024-bp-long chromosome sequences flanked by the right border of the T-DNA region was deleted. A 370-bp long left border region and 199-bp long right border region corresponding to the matrix attachment region (MAR) sequences of the T-DNA were also deleted. Collectively, these results indicate that whole-genome shotgun sequencing is a useful tool to reveal the detailed sequences and structures of the introduced T-DNAs, especially in the case of multiple T-DNA insertions. The expenses incurred on genome sequencing can be easily compensated by minimizing the time and efforts invested in conventional molecular analyses.