Preliminary Study of Viruses Infecting Strawberry (Fragaria spp.) in the Midsouthern United States

Abstract

Strawberry is an important economic crop in the midsouthern United States; however, limited information is known about the viruses present in strawberry fields in Arkansas, Missouri, Oklahoma, and Texas. The purpose of this study was to determine the presence of particular viruses infecting strawberry crops in these four states. A total of 816 strawberry leaf samples were randomly collected from growers’ fields during the 2014 and 2016 growing seasons and tested by dot-immunobinding assay against antisera of eight available viruses: apple mosaic virus (ApMV), arabis mosaic virus (ArMV), raspberry bushy dwarf virus (RBDV), raspberry ringspot virus, strawberry mild yellow edge virus (SMYEV), tobacco necrosis virus, tomato black ring virus, and tomato ringspot virus (ToRSV). Of the eight viruses, ApMV, RBDV, and SMYEV had the highest infection rates in 2014, whereas ApMV, ArMV, ToRSV and SMYEV were the most prevalent viruses in 2016. Mixed infection of more than one virus was very common in samples collected from all four states. Our preliminary results showed that the distribution of virus relative frequencies differed significantly among seven sample locations across the states within a sample year, but we could not show statistical differences among the years based on our sample sizes. Mixed infections in strawberries were higher than expected in 2014 and lower than expected in 2016 based on viruses being independent infections. Overall, the occurrence of the viruses in strawberry crops could have important potential impacts for strawberry production in the midsouthern states.