We isolated and compared three tomato spotted wilt virus (TSWV) isolates from lettuce (TSWV-Let), pepper (TSWV-Pep), and tomato (TSWV-Tom) from central Mexico to determine their ability to infect a set of eighteen differential plant species from seven families. TWSV-Let was an aggressive isolate with the ability to infect up to 52% of the differential plants, including maize, under greenhouse conditions. The nucleotide (nt) sequences of the three isolates are more than 90% similar in the M and S RNA segments. In the M segment of the TSWV-Let isolate, we detected nt changes in their intergenic region (IGR) and, in the Gc gene, a region containing a recombination site, as well as a synapomorphy associated with one of three sites under positive selection with a change in one aa residue (a cysteine-to-valine mutation). We speculate on the association of these features in the Gc gene with host selection, adaptation, aggressiveness, and ability to infect maize plants.

我们从墨西哥中部的莴苣（TSWV-Let），胡椒（TSWV-Pep）和番茄（TSWV-Tom）分离并比较了三种番茄斑萎病毒（TSWV）菌株，以确定它们感染一组18种差异植物的能力来自七个科的物种。TWSV-Let是一种攻击性分离株，能够在温室条件下感染多达52％的差异植物，包括玉米。这三个分离株的核苷酸（nt）序列在M和S RNA片段中有超过90％的相似性。在TSWV-Let分离物的M段中，我们检测到其基因间区域（IGR）的nt变化，并且在Gc基因中检测到包含重组位点的区域，以及与正选择作用下与三个位点之一相关的突触改变一个氨基酸残基（半胱氨酸到缬氨酸突变）。