云南丽江金沙江流域优质烟区番茄斑萎病毒中间寄主调查与鉴定OA

Tomato spotted wilt virus(TSWV)belongs to the genus Orthotospovirus and is a negative-sense RNA virus that often causes serious damage to economically important crops such as tomato,pepper and tobacco.During 2021-2023,33 tobacco and 219 weeds leaf samples suspected of TSWV infection were collected from tobacco-growing areas in the Jinsha River Basin of Lijiang,Yunnan province.Using a colloidal gold immunochromatographic rapid test kit,TSWV infection was detected in 24 tobacco samples(72.72％)and 89 weed samples(40.63％).The positive weed hosts belonged to 13 families,21 genera and 24 species,among which Pinellia ternata and Melissa axillaris were identified as new hosts of TSWV.Electron microscopy observation revealed spherical virions with diameters of approximately 80-90 nm in infected tobacco and Bidens pilosa,exhibiting typical morphological characteristics of viruses in the genus Orthotospovirus.Through RT-PCR detection,cloning,and sequencing,a total of 19 TSWV N gene sequences were obtained.Sequence similarity analysis showed that the nucleotide identities of these 19 N gene sequences and their identities with TSWV N gene sequences from other isolates ranged from 97.8％to 99.9％.Phylogenetic trees showed that the 19 TSWV N gene sequences obtained in this study clustered with TSWV isolates from China and showed close genetic relationships.Population genetic diversity analysis revealed that the genetic diversity of the TSWV weed population was higher than that of the TSWV tobacco population.These results contribute to a better understanding of host species and the occurrence and epidemic patterns of TSWV in the Jinsha River Basin of Lijiang,Yunnan province,and provide a theoretical basis for the integrated management of diseases caused by TSWV infection in this region.