番茄斑驳花叶病毒在我国茄科作物上的发生及生物学特性

【目的】鉴定烟草花叶病毒属（Tobamovirus）新种番茄斑驳花叶病毒（Tomato mottle mosaic virus,ToMMV）当前在我国茄科作物上的发生危害情况、主要分布地区和自然寄主,明确其主要寄主范围、传播途径和致病性等生物学特性。【方法】利用RT-PCR方法对2013—2017年采自我国云南、贵州、四川、海南、湖南、河南、陕西、山东、湖北、浙江、辽宁、西藏和内蒙古13个省（自治区）,表现为花叶、皱缩、畸形、黄化、坏死等疑似病毒病症状的茄科作物辣椒、番茄、茄子、马铃薯和烟草等样品进行ToMMV的检测。分别将ToMMV进行摩擦接种和注射接种,对感染ToMMV的珊西烟获得的种子及由种子萌发的幼苗进行ToMMV检测,对由健康种子萌发且在含有ToMMV毒源土壤中生长的6—8叶龄辣椒和番茄幼苗进行ToMMV检测,以此开展ToMMV传播方式的测试。在茄科、葫芦科、豆科和十字花科等6科30种植株上开展ToMMV的寄主范围鉴定和不同辣椒、番茄材料对ToMMV的抗性鉴定。【结果】我国13个省（区）共采集茄科作物疑似病毒病样品1 622份,ToMMV的平均检出率为2.59%,目前ToMMV已在我国云南、湖南、海南、辽宁、陕西、西藏和内蒙古7个省（区）发生。其中云南、湖南、海南、陕西和西藏的辣椒上有ToMMV的发生,而云南、海南、辽宁及内蒙古的番茄上有ToMMV的发生,平均检出率分别为2.51%和3.46%,尚未在茄子、马铃薯和烟草样品中检测到ToMMV的侵染。ToMMV可通过摩擦、注射、种子带毒及土壤带毒进行传播,且种子带毒率越高,对种苗生长的影响越大;寄主范围测试发现,ToMMV可侵染几乎所有供试的茄科和十字花科植物,及部分豆科和葫芦科植物。筛选出对ToMMV免疫的辣椒材料1份、高抗的辣椒材料2份以及对ToMMV高抗的番茄材料2份。【结论】ToMMV目前已在我国辣椒、番茄上发生,人工条件下ToMMV的寄主范围较广,致病力强,在我国有逐渐扩散和流行的趋势,很可能会成为未来蔬菜作物尤其是茄科作物上危害严重的主要病毒之一。

Occurrence and Biological Characteristics of Tomato mottle mosaic virus on Solanaceae Crops in China

【Objective】The objective of this study is to determine the occurrence, main distribution area, natural host and biological characteristics including host range, transmission way and pathogenicity of Tomato mottle mosaic virus (ToMMV) in solanaceae crops of China, which is a newly identified species in the genus Tobamovirus.【Method】Using RT-PCR method, the suspected virus-infected pepper, tomato, eggplant, potato, tobacco of solanaceae crops showing mosaic, shrinking, malformation, yellowing, necrosis symptoms collected from 13 provinces/autonomous regions (Yunnan, Guizhou, Sichuan, Hainan, Hunan, Henan, Shaanxi, Shandong, Hubei, Zhejiang, Liaoning, Tibet and Inner Mongolia) of China in 2013-2017 were detected. Transmission ways were tested by mechanical inoculation and injection, by ToMMV detection in the seeds obtained from ToMMV-infecting tobacco and the seedlings germinated from the seeds, as well as in the 6-8 leaves seedlings of pepper and tomato germinated from the healthy seeds grew in the ToMMV-contaminated soils. Host range test of ToMMV on 30 plants in 6 families such as Solanaceae, Cucurbitaceae, Leguminosae, Cruciferae and disease resistance evaluation of different pepper and tomato varieties against ToMMV were carried out.【Result】A total of 1 622 suspected virus-diseased samples of solanaceae crops were collected from 13 provinces/autonomous regions, and the average detection rate of ToMMV was 2.59%, which occurred in 7 provinces/autonomous regions including Yunnan, Hunan, Hainan, Liaoning, Shaanxi, Tibet and Inner Mongolia. ToMMV infection in pepper was detected in Yunnan, Hunan, Hainan, Shaanxi and Tibet, while the infection of ToMMV in tomato was detected in Yunnan, Hainan, Liaoning and Inner Mongolia, with the average detection rates of 2.51% and 3.46%, respectively. No ToMMV was detected in eggplant, potato and tobacco. ToMMV could be transmitted by mechanical inoculation, injection, virus-contaminated seeds and virus-contaminated soils under experimental conditions, and showed the higher ToMMV infection rate in the seeds, the greater impact on the growth of seedlings. ToMMV could infect almost all of the tested solanaceae and cruciferae plants, and some leguminosae and cucurbitaceae plants. One pepper germplasm material was identified as immune to ToMMV, and two pepper germplasm materials were high resistance to ToMMV, while two tomato germplasm materials showed high resistance to ToMMV.【Conclusion】ToMMV has been occurring on pepper and tomato in China at present, and the host range of ToMMV is wide and the pathogenicity is strong under experimental conditions. ToMMV has a gradual spread and epidemic trend in China, and it is likely to become one of the most harmful viruses on vegetable crop production, especially in solanaceae crops in the future.