Soybean mosaic virus (SMV), a member of Potyviridae family, is one of the most typical viral diseases and results in yield and quality loss of cultivated soybean. Due to the depletion of genetic resources for resistance breeding, a trial of genetic transformation to improve disease resistance has been performed by introducing SMV-CP and HC-Pro gene by RNA interference (RNAi) method via Agrobacterium-mediated transformation. Transgenic plants were infected with SMV strain G5 and investigated the viral response. As a result, two lines (3 and 4) of SMV-CP(RNAi) transgenic plants and three lines (2, 5 and 6) of HC-Pro(RNAi) transgenic plants showed viral resistance. In genomic Southern blot analysis, most of lines contained at least one T-DNA insertion in both SMV-CP(RNAi) and HC-Pro(RNAi) transgenic plants. Subsequent investigation confirmed that no viral CP and HC-Pro gene expression was detected in two SMV-resistant lines of SMV-CP(RNAi) and three lines of HC-Pro(RNAi) transgenic plants, respectively. On the other hand, non-transgenic plants and other lines showed viral RNA expression. Viral symptoms affected seed morphology, and clean seeds were harvested from SMV-resistant line of SMV-CP(RNAi) and HC-Pro(RNAi) transgenic plants. In addition, strong viral gene expression was detected from seeds of SMV-susceptible non-transgenic plants and SMV-susceptible transgenic lines. When compared the viral resistance between SMV-CP(RNAi) and HC-Pro(RNAi) transgenic plants, soybean transgenic plants with the HC-Pro gene using RNAi strategy showed much stronger and higher frequency of viral resistance.

• Young Soo Chung(Dept. of Genetic Engineering, Dong-A University) Corresponding Author
• Kook-Hyung Kim(Dept. of Agricultural Biotechnology and Plant Genomics and Breeding Institute, Seoul National University)
• Ki Hyun Ryu(Division of Environmental and Life Sciences, Seoul Women’s University)
• Yeong Hoon Lee(National Institute of Crop Science, RDA)
• Hyun Hee Im(Dept. of Genetic Engineering, Dong-A University)
• Yoon Jeong Lee(Dept. of Genetic Engineering, Dong-A University)
• Hyun Suk Cho(Dept. of Genetic Engineering, Dong-A University)
• Su Yeong Yun(Dept. of Genetic Engineering, Dong-A University)
• Hye Jeong Kim(Dept. of Genetic Engineering, Dong-A University)