西藏部分地区紫花苜蓿病毒病病原鉴定

Identification the pathogen of alfalfa virus disease in some areas of Tibet

对西藏自治区扎囊县、达孜县和林芝市部分地区紫花苜蓿(Medicago sativa)病毒病进行调查,发现病毒病在以上地区均有发生,症状表现为花叶、小叶、斑驳、皱缩、红化、黄化等。利用深度测序技术结合RT-PCR,对2020年8月和2021年7月采自扎囊县、达孜县和林芝市的211份疑似病毒病的紫花苜蓿样品进行检测,发现侵染西藏紫花苜蓿的病毒有苜蓿花叶病毒(AMV)、苜蓿混合病毒1(MsAV1)、苜蓿暂时性线条病毒(LTSV)和黄瓜花叶病毒(CMV)4种,病毒总检出率为31.8%,AMV、MsAV1、LTSV和CMV的检出率分别为17.1%、10.4%、3.3%和5.7%。存在两种病毒复合侵染的现象,检出率分别为AMV+MsAV11.4%、AMV+LSTV 2.4%、CMV+MsAV10.5%、AMV+CMV0.5%。这是MsAV1、AMV和LTSV在西藏地区的首次报道,也是CMV在中国苜蓿上的首次报道,研究结果将为西藏地区紫花苜蓿病毒病的防控提供参考。

Medicago sativa viral diseases were surveyed in partial planting areas of Zhanang County,Dazi County and Nyingchi City in Tibet Autonomous Province.The results showed that viral diseases occurred in all the above regions with symptoms of mosaic,smaller leaves,mottle,shrinking,reddening and yellowing.To identify the disease plants’potential pathogen,deep sequencing and RT-PCR technology were conducted on 211 symptomatic leaves samples collected in August 2020 and July 2021.Four viruses of alfalfa mosaic virus(AMV),M.sativa virus 1(MsAV1),lucerne transient streak virus(LTSV)and cucumber mosaic virus(CMV)were found infecting these samples with a total detection rate of 31.8%.The detection rates of AMV,MsAV1,LTSV and CMV were 17.1%,10.4%,3.3%and 5.7%respectively.The complex infection occurred between two viruses with the detection rate of AMV+MsAV11.4%,AMV+LSTV 2.4%,CMV+MsAV1 and AMV+CMV 0.5%.This is the first report of AMV,MsAV1and LTSV in Tibet and CMV in alfalfa in China.These results will provide a reference for preventing and controlling alfalfa virus disease in Tibet.