Virus host range, i.e., the number and diversity of host species of viruses, is an important determinant of disease emergence and of the efficiency of disease control strategies. However, for plant viruses, little is known about the genetic or ecological factors involved in the evolution of host range. Using available genome sequences and host range data, we performed a phylogenetic analysis of host range evolution in the genus Potyvirus, a large group of plant RNA viruses that has undergone a radiative evolution circa 7000 years ago, contemporaneously with agriculture intensification in mid Holocene. Maximum likelihood inference based on a set of 59 potyviruses and 38 plant species showed frequent host range changes during potyvirus evolution, with 4.6 changes per plant species on average, including 3.1 host gains and 1.5 host loss. These changes were quite recent, 74% of them being inferred on the terminal branches of the potyvirus tree. The most striking result was the high frequency of correlated host gains occurring repeatedly in different branches of the potyvirus tree, which raises the question of the dependence of the molecular and/or ecological mechanisms involved in adaptation to different plant species.

中文翻译：

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杯状病毒宿主范围的进化：全球系统发育分析。

病毒宿主范围，即病毒宿主种类的数量和多样性，是决定疾病出现和疾病控制策略效率的重要因素。但是，对于植物病毒，关于宿主范围进化的遗传或生态因素知之甚少。我们使用可获得的基因组序列和寄主范围数据，对马铃薯病毒属中的寄主范围进化进行了系统进化分析。该病毒是一大批植物RNA病毒，大约在7000年前就经历了辐射进化，同时与全新世中期的农业集约化同时进行。基于一组59种夜蛾病毒和38种植物的最大似然推断显示，在夜蛾病毒进化过程中宿主频率频繁变化，平均每株植物发生4.6种变化，包括3.1种宿主增加和1.5种宿主损失。这些变化是最近才发生的，其中74％是在马铃薯病毒树的末端分支上推断出来的。最惊人的结果是在马铃薯花叶病毒树的不同分支中反复出现的相关寄主获得的频率很高，这提出了依赖于适应不同植物物种的分子和/或生态机制的依赖性问题。