Small RNA Analysis of Virus-virus Interaction between Two Orthotospoviruses

Mixed infections of plant viruses are commonly found in natural patho-systems and present a valuable opportunity to understand how multiple viruses can co-infect the same host. Tomato spotted wilt orthotospovirus (TSWV) and impatiens necrotic spot orthotospovirus (INSV) are present in the same geographic areas and are closely related. More mixed infections of TSWV and INSV have been reported in recent years, and the INSV host range has been reported to be increasing. In a previous study, we have isolated one strain of INSV and one of TSWV and showed that they have an antagonistic relationship in their vectors, but we were unable to determine, the underlying mechanisms governing their antagonism in planta and the contribution of the host to this. Here, we used small RNA sequencing to study TSWV-INSV antagonistic interaction and showed that INSV alters plant responses and the processing of TSWV.