LAUSR

Abstract Orthotospoviruses have become one of the major threats to vegetable crops worldwide. Recently, severe outbreaks of Tomato spotted wilt virus (TSWV) and Tomato yellow ring virus (TYRV) have been observed in tomato production regions in Poland. In this study, a multiplex RT-PCR assay was developed and optimized for the simultaneous detection of these two viruses. Primers were designed to amplify 666 bp and 328 bp of the nucleocapsid (N) genes of TYRV and TSWV, respectively. The multiplex RT-PCR detection limit was 1 pg μL−1 of total RNA, and it was successfully applied for the detection of TSWV and TYRV in 21 samples of tomato, tobacco and weed plants collected in Poland. Four samples were found to be co-infected with both viruses, whereas infection solely with TSWV and TYRV was found in 9 and 8 samples, respectively. Overall, this study presents a rapid, specific and sensitive method for orthotospoviruses identification in plants that can be applied to mixed infections.