Molecular Identification Of The Mosaic Disease From Salvia Splendens

【Objective】 Salvia splendens is an important annual ornamental plant grown worldwide. It isvery popular as bedding plant, seen in public gardens. After close observation of thevariegated foliage at a local garden in Shihezi, the resembled symptoms caused by plantviruses were noticed. The symptoms consisted of mosaic, stunt and wither. The pathogen weredetected and identified for prevention and cure of this disease.【Methods】 The leaf samples with mosaic symptom were collected from garden in Shihezi.Following mechanical inoculation onto a range of indicator plants, symptoms were observedand dsRNA or total RNA was extracted from leaves. The RT-PCR was amplified. The DNAfragments were cloned into pMD18-T and the sequence were determined and analysed.【Results】 The necrotic lesions and/or systemic symptoms were obtained on several testplants by mechanical inoculation onto leaves.The approximate4700bp and6300bp dsRNAfragments were obtained by extraction from mosaic leaves of S4isolate Salvia (Salviasplendens). As the template, the approximate400bp fragments were amplified by usinguniversal primers of Fabavirus. The sequences was determined to be391nucleotides andshared from78to100percent nucleotide sequence identities with5，-NCR of RNA1of Beanbroad wilt virus2(BBWV2). It was concluded that Salvia showing mosaic symptom wereinfected by BBWV2. Based on the determined sequence and accessed genomes of BBWV2inGenBank, the primer pairs in conserved region were designed to further amplify the genomesequence of S4. The results showed that complete genomes RNA1was comprised of5957nucleotides and contained a large open reading frame (ORF). It shared from78.4to100.0percent sequence identities with RNA1of other BBWV2isolates in GenBank and equaled toisolate XJP1-1in pepper from same geography region in China. The genomes RNA2wascomprised of3618nucleotides and contained a large open reading frame (ORF) also. It sharedfrom80.4to93.0percent sequence identities with RNA2of other BBWV2isolates inGenBank. It shared the highest identities with isolate XJP1-1(93.0%) and the lowest identitieswith XJ14-3a solate (80.4%) from same geography region in China.【Conclusion】 In this study, the symptoms consisted of mosaic, stunt and wither was infectedby BBWV2of Shihezi, and the molecular characters of S4were isolate clear and definite.This is the first report of this virus infected S. splendens.