A fast and efficient method to introduce apple latent spherical virus to legume plants via Agrobacterium rhizogenes-mediated transformation of hairy roots

Virus-induced gene silencing (VIGS) is a functional genomics tool used to determine the function of unknown genes or assess the impact of gene silencing on plant phenotype. However, VIGS methods for analyzing gene function are not equally efficient across species, and virus inoculation is difficult for some legume species. We describe a fast and efficient inoculation method using Agrobacterium rhizogenes K599 harboring an apple latent spherical virus (ALSV) full-length cDNA clone. Pisum sativum cv. AAC Lacombe and Lens culinaris cv. CDC Viceroy showed silencing rates of 100% and 47.7%, respectively, within 30 days starting from seed. To our knowledge, this is the first report of virus inoculation by A. rhizogenes-mediated introduction to legume plants. This work paves the way for high throughput gene function screening in Pisum sativum and other closely related legume crops using ALSV as a symptomless VIGS vector.