云南西瓜银灰斑驳病毒病害的鉴定

 应用DAS-ELISA和RT-PCR方法从褪绿和银色斑驳的西瓜叶片中检测到病毒分离物（WSMoV-YN），感病样品能与WSMoV/GBNV复合抗血清（Agdia）呈阳性反应。获得WSMoV N蛋白的多克隆抗体，抗体能与WSMoV血清组成员CaCV和TZSV反应，但不能与INSV、TSWV、HCRV和GYSV反应。为明确引起该病害的病毒种类，采用Tospovirus通用引物对样品的总RNA进行RT-PCR扩增，获得长度为3 554 nt的S RNA全序列，经Blastn比对分析与WSMoV中国台湾分离物同源性最高，为95.8%，其N和NSs蛋白氨基酸序列同源性分别为99%和97.6%。构建系统进化树发现，西瓜银灰斑驳病毒云南分离物（WSMoV-YN）与其他WSMoV聚为一支。确定引起云南西瓜病害的病毒为WSMoV。

Identification of Watermelon silver mottle virus infecting watermelon in Yunnan

Using DAS-ELISA and RT-PCR, a viral isolate (WSMoV-YN) was detected in watermelon showing chlorotic and silver mottle. Diseased samples were positive for antibodies to Watermelon silver mottle virus (WSMoV) and Groundnut bud necrosis virus (GBNV) (Agdia, USA). The polyclonal antiserum of N protein were obtained and could react with Capsicum chlorosis virus (CaCV) and Tomato zonate spot virus (TZSV), the members of Watermelon silver mottle virus (WSMoV) serogroup, but not react with Impatiens necrotic spot virus (INSV), Tomato spotted wilt virus (TSWV), Hippeastrum chlorotic ringspot virus (HCRV) and Groundnut yellow spot virus(GYSV). To further confirm the presence of WSMoV, the samples were examined by RT-PCR using tospovirus universal primer pairs. Full-length sequence of WSMoV-YN S RNA with a length of 3 554 nt was obtained and sequence alignment indicated that WSMoV-YN shares 95.8% identity with WSMoV isolates from Taiwan, China (NC_003843) at the nucleotide level. The nucleocapsid protein (N) and non-structual (NSs) shared 99% and 97.6% amion acid identity with the Taiwan(China) isolates, respectively. Taken together, our results suggested that the WSMoV-YN formed a distinct cluster with the other WSMoV isolates.