Tomato chlorosis virus (ToCV), transmitted by whiteflies, is an important virus that infect tomato plants worldwide. The incidence of ToCV in tomato crops in Brazil is usually high, especially in the Distrito Federal and the state of Goiás, in the central part of the country. We conducted a survey in central Brazil to detect natural infections of ToCV in weeds near tomato plants with typical criniviral symptoms to determine the possible causes of its high incidence. We also conducted an experimental host range study using a Brazilian ToCV isolate, ToCV-BR. ToCV was only detected in three out of 19 weed species collected under natural conditions: Solanum americanum, Nicandra physaloides and Amaranthus viridis. Although these species are the most important weeds, occurring at high frequencies associated with tomato crops in Brazil, the number of weed species infected by ToCV was low in the vicinity of tomato fields. In experimental trials of whitefly ( Bemisia tabaci ) transmission, the ToCV-BR isolate infected 10 out of 50 plant species tested. The natural abundance of both whiteflies and ToCV-susceptible plants in the field throughout the year may affect the incidence of ToCV in tomato in central Brazil.

中文翻译：

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巴西中部采集的杂草中番茄萎黄病病毒的宿主范围和自然感染

由粉虱传播的番茄萎黄病毒（ToCV）是一种重要的病毒，可感染全世界的番茄植物。巴西番茄作物中 ToCV 的发病率通常很高，尤其是在该国中部的联邦区和戈亚斯州。我们在巴西中部进行了一项调查，以检测具有典型新病毒症状的番茄植株附近杂草中 ToCV 的自然感染，以确定其高发病率的可能原因。我们还使用巴西 ToCV 分离株 ToCV-BR 进行了实验性宿主范围研究。ToCV 仅在自然条件下收集的 19 种杂草中的 3 种中检测到：Solanum americanum、Nicandra physaloides 和 Amaranthus viridis。尽管这些物种是最重要的杂草，在巴西与番茄作物相关的发生频率很高，在番茄田附近，受 ToCV 感染的杂草种类数量很少。在粉虱 (Bemisia tabaci) 传播的实验性试验中，ToCV-BR 分离株感染了 50 种测试植物中的 10 种。全年田间粉虱和 ToCV 易感植物的自然丰度可能会影响巴西中部番茄中 ToCV 的发病率。