High-Level Expression of Sporamin in Transgenic Chinese Cabbage Enhances Resistance Against Diamondback Moth

This study introduced the protease inhibitor-encoding gene sporamin from sweet potato together with the wound-responsive promoter pMSPOA into the Chinese cabbage (Brassica campestris ssp. chinensis var. parachinensis) through Agrobacterium tumefaciens-mediated transformation. Transgenic lines were confirmed via PCR detection of both the sporamin and hygromycin gene fragments in the cloning vector. The expression level of sporamin in the different lines was determined using RT-PCR analysis. Leaves from four individual transgenic lines including T0-2, T0-3, T0-4 and T0-5, possessing higher levels of sporamin than control plants, were then used to conduct insect feeding studies. Second instar larvae of diamondback moth (Plutella xylostella L.) were used in feeding assays. All four transgenic lines demonstrated high levels of resistance against diamondback based on average body weight of total incubated larvae following feeding assays and amount of leaf damage.