CGMMV (cucumber green mottle mosaic virus) infects many cucurbitaceae species causing mosaic symptoms, yellowish leaf, and fruit deterioration. Several isolates of CGMMV from Korea, Israel, Japan, Greece and Spain have been characterized. In fact, CGMMV outbreaks have caused huge losses in the total yields of cucurbitaceous crops in Korea. Unfortunately, no genetic source is available for the resistance against CGMMV infection, and therefore, the breeding management offers no access to a solution yet. Thus, an alternative was to transform the viral gene such as CGMMV-CP into crops to induce tolerance against CGMMV. Here, we present the successful transformation of watermelon rootstock (gongdae) by Agrobacterium-mediated transformation with the CGMMV-CP gene. We obtained 29 independent T0 watermelon rootstock plants from the transformation of 7,887 explants. T0 plants were self-crossed and T1 plants were screened by the virus infection. Those gongdaes tolerant to virus were selected continuously, and BC2T1 and T3 generation were obtained. We have also obtained watermelons of BCF generation by crossing GM gongdae to watermelon line and those BCF watermelones were strongly tolerant to CGMMV.

• So Youn Lee(Biotechnology Institute, Nongwoo Bio Co.)
• Yuon Sub Shin(Biotechnology Institute, Nongwoo Bio Co.)
• Ki Hyun Ryu(Breeding Institute, Nongwoo Bio Co.)
• Chee Hark Harn(Biotechnology Institute, Nongwoo Bio Co.) Corresponding Author