Disease-resistant transgenic adzuki bean plants obtained through an efficient transformation system

Abstract

An efficient regeneration and transformation system was established and optimised for adzuki bean (Vigna angularis (Willd.) Ohwi & Ohashi). 6-Benzylaminopurine at 5 mg L–1 was used to increase adventitious bud induction frequency. The highest frequency of shoot elongation was 92.8% when using a medium composition of MS salts combined with 0.1 mg L–1 of IAA, 0.5 mg L–1 of GA3, 1.0 mg L–1 of zeatin-riboside, 50 mg L–1 of aspartic acid, and 50 mg L–1 of glutamic acid. In vitro rooting was 100% when shoots were cultured on the solid MS medium supplemented with 1.0 mg L–1 of NAA. Reproducible transformation of epicotyl explants was developed using the A. tumefaciens EHA105 strain. Using a concentration of 40 mg L–1 of acetosyringone, 20 mm MES, and 5 mg L–1 of 6-benzylaminopurine in the co-cultivation medium, a transformation efficiency of 12.6% was attained. Using this transformation protocol, we obtained transgenic adzuki bean plants resistant to soybean mosaic virus by introducing the V. angularis VaPR3 gene.