L-Cysteine Increases the Transformation Efficiency of Chinese Cabbage ( ssp. ).

Successful -mediated transformations of Chinese cabbage have been limited owing to the plant's recalcitrant nature, genomic background and explant necrosis upon infection, which hinders the transfer of T-DNA region into the Chinese cabbage. Consequently, in the current experiment, a stable mediated transformation method for Chinese cabbage cv. Kenshin established by employing important anti-oxidants in the co-cultivation and subsequent regeneration media. Four-day-old derived cotyledon explants were infected with strain GV3101 harboring the vector pCAMIBA1303. Cotyledon explants exposed to an suspension (OD of approximately 0.6) for 10 min and then incubated for 3 days co-cultivation in Murashige and Skoog medium containing an L-cysteine + AgNO combination exhibited the highest β-glucuronidase (GUS) expression (94%) and explant regeneration efficiency (76%). After 3 days, the cotyledon explants were subjected to three selection cycles with gradually increasing hygromycin B concentrations (10 to 12 mg/L). The incorporation and expression of in T transformed plants were verified by polymerase chain reaction and Southern blot analyses. These transgenic plants (T) were fertile and morphologically normal. Using the present protocol, a successful transformation efficiency of 14% was achieved, and this protocol can be applied for genome editing and functional studies to improve Chinese cabbage traits.