An efficient beet severe curly top virus-based VIGS vector in Beta vulgaris

Abstract

Sugar beet (Beta vulgaris L.) is one of the most important sugar crops worldwide. However, studies on sugar beet gene functions are still lagging compared to other crops due to the lack of an effective genetic manipulation. In this study, we generated an infectious clone of beet sever curly top virus (BSCTV) and engineered it into a VIGS vector. BSCTV-BvPDS can induce strong and persistent bleached PDS-silencing phenotype in 8 tested sugar beet varieties. We further efficiently silenced B. vulgaris MYB1 gene that regulating the betalain pathway in sugar beet by BSCTV-based VIGS system. Finally, we used this system to silence the effector CbNip1 of Cercospora beticola through cross-kingdom RNAi, resulting in reduced disease symptoms in sugar beet plants. Therefore, the BSCTV VIGS system can be used to study sugar beet-pathogen interactions. In summary, we have established an easy and efficiency BSCTV-based VIGS vector in sugar beet. This system will be an attractive tool for functional genomic studies for sugar beet.