Plant Virome Analysis by the Deep Sequencing of Small RNAs of Fritillaria thunbergii var. chekiangensis and the Rapid Identification of Viruses

Thunberg fritillary (Fritillaria thunbergii), a perennial used in traditional Chinese herbal medicine, is a members of the family Liliaceae. The degeneration of germplasm is a severe problem in the production of Fritillaria thunbergii var. chekiangensis. However, no information about viral infections of F. thunbergii var. chekiangensis has been reported. In this study, we sequenced the small RNAs of F. thunbergii var. chekiangensis from leaves and bulbs, and viruses were identified using a phylogenetic analysis and BLAST search for sequence. In addition, multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) was used to rapidly detect viruses in this variety. Our study first reported that five viruses infected F. thunbergii var. chekiangensis. Among them, fritillary virus Y (FVY), lily mottle virus (LMoV), Thunberg fritillary mosaic virus (TFMV), and hop yellow virus (HYV) had been reported in F. thunbergii, while apple stem grooving virus was first reported in the genus Fritillaria. A multiplex RT-PCR method was developed to rapidly test the four viruses FVY, LMoV, TFMV, and HYV in F. thunbergii var. chekiangensis. Our results provide a better understanding of the infection of F. thunbergii var. chekiangensis by viruses and a basic reference for the better design of suitable control measures.