Abstract Sugarcane yellow leaf virus (SCYLV) is an aphid-transmitted virus for which Melanaphis sacchari is the main vector. Almost all sugarcane varieties grown in Florida are susceptible to SCYLV infection. In this study, we investigated the prevalence of SCYLV in accessions of Sorghum bicolor which is another natural host of this virus. Two field experiments, one in 2016 with 19 sorghum lines and the other in 2017 with 15 lines, were established at Belle Glade, FL. Stalks collected randomly in planted and ratoon crops were tested by tissue-blot immunoassay (TBIA) and reverse transcription-polymerase chain reaction (RT-PCR). Over the two-year period, 366 of 423 S. bicolor samples tested positive by TBIA but SCYLV was detected by RT-PCR in only 12 of 161 randomly selected subsamples. Full genome sequences of SCYLV, sugarcane mosaic virus (SCMV) and a new marafivirus were obtained by high-throughput sequencing (HTS) from three TBIA positive sorghum samples. HTS data for all three viruses were confirmed by RT-PCR. The SCMV isolate from S. bicolor appeared to be a new strain of this virus species. Positive reaction of S. bicolor by TBIA using SCYLV antibodies could not be systematically associated with plant infection by SCYLV or another virus. This suggested the occurrence of a non-specific serological reaction with an unknown S. bicolor antigen. SCMV and the new marafivirus were also detected in Sorghum almum, suggesting that this weed is a reservoir for S. bicolor-infecting viruses in Florida.

中文翻译：

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佛罗里达州高粱中甘蔗黄叶病毒的筛查揭示了它在甘蔗花叶病毒和一种新的马拉菲病毒的混合感染中发生

摘要 甘蔗黄叶病毒（SCYLV）是一种蚜虫传播的病毒，以甘蔗黑斑病为主要传播媒介。佛罗里达州种植的几乎所有甘蔗品种都易受 SCYLV 感染。在这项研究中，我们调查了 SCYLV 在双色高粱种质中的流行情况，该种质是该病毒的另一个天然宿主。在佛罗里达州贝尔格莱德 (Belle Glade) 开展了两项田间试验，一项于 2016 年进行了 19 个高粱品系，另一项于 2017 年进行了 15 个品系。通过组织印迹免疫分析 (TBIA) 和逆转录聚合酶链反应 (RT-PCR) 测试在种植和宿根作物中随机收集的茎。在两年期间，423 个双色链球菌样本中有 366 个经 TBIA 检测呈阳性，但通过 RT-PCR 仅在 161 个随机选择的子样本中的 12 个中检测到 SCYLV。SCYLV的全基因组序列，通过高通量测序 (HTS) 从三个 TBIA 阳性高粱样品中获得甘蔗花叶病毒 (SCMV) 和一种新的 marafivirus。所有三种病毒的 HTS 数据均通过 RT-PCR 确认。来自双色链球菌的 SCMV 分离物似乎是该病毒种的新毒株。S. bicolor 使用 SCYLV 抗体通过 TBIA 产生的阳性反应不能与 SCYLV 或其他病毒感染植物系统相关。这表明发生了与未知双色链球菌抗原的非特异性血清学反应。在 Sorghum almum 中也检测到 SCMV 和新的 marafivirus，这表明这种杂草是佛罗里达州双色链球菌感染病毒的宿主。来自双色链球菌的 SCMV 分离物似乎是该病毒种的新毒株。S. bicolor 使用 SCYLV 抗体通过 TBIA 产生的阳性反应不能与 SCYLV 或其他病毒感染植物系统相关。这表明发生了与未知双色链球菌抗原的非特异性血清学反应。在 Sorghum almum 中也检测到 SCMV 和新的 marafivirus，这表明这种杂草是佛罗里达州双色链球菌感染病毒的宿主。来自双色链球菌的 SCMV 分离物似乎是该病毒种的新毒株。S. bicolor 使用 SCYLV 抗体通过 TBIA 产生的阳性反应不能与 SCYLV 或其他病毒感染植物系统相关。这表明发生了与未知双色链球菌抗原的非特异性血清学反应。在 Sorghum almum 中也检测到 SCMV 和新的 marafivirus，这表明这种杂草是佛罗里达州双色链球菌感染病毒的宿主。