Effect of strawberry vein banding virus and strawberry mottle virus co-infection on the growth and development of strawberry

Abstract

Strawberry mottle virus (SMoV) and strawberry vein banding virus (SVBV) cause diseases on strawberry plants, but the effect of coinfection of SMoV and SVBV on the growth, development, and defense system of strawberry (Fragaria × ananassa Duchesne) remains unknown. We investigated the effect of SMoV and SVBV co-infection on strawberry cultivar ‘Benihope’. The results showed that stem diameter, leaf size, leaf number, relative chlorophyll content, total chlorophyll content, photosynthetic parameters, and stomatal aperture of SMoV and SVBV co-infected strawberry (VIS) plants were in a weaker level than uninfected control plants, indicating that viruses inhibited the growth and photosynthesis of strawberry plants. Furthermore, the initiation of flowering and fruiting stages of VIS plants were delayed by about three weeks compared with the controls, and the fruiting period was shortened, demonstrating that the reproduction of VIS plants was inhibited. Fruit quality was damaged in VIS plants due to a significant increase in fruit firmness and titratable acidity and decrease in total soluble solid content than control fruits. More dead cells and H₂O₂ accumulated along the veins of VIS leaves, and the content of abscisic acid and catalase activity significantly increased, whereas anthocyanin content was lower than that of control plants. The results demonstrate that SVBV and SMoV coinfection inhibits the growth and development of ‘Benihope’ strawberry plants, and the plants respond to viruses by regulating stomatal aperture, the accumulation of ABA and antioxidants. To our knowledge, this study contributes information to understand how both viruses impair the strawberry growth and development for the first time.