Viruses and the Diseases They Cause in Berries

More than 100 viruses infect berry crops. Some of them have a wide host range and cause severe symptoms, such as tobacco ringspot virus (TRSV), which can infect all of the crops covered by NCPN.  Others have a very narrow host range, such as blueberry scorch virus, which is only known to infect Vaccinium and Sambucus species. Blueberry scorch virus can cause nearly 100% flower and leaf necrosis in some blueberry cultivars.

 

In many cases, virus diseases in berry crops are caused by a complex of two or more viruses (Martin et al., 2012; Martin and Tzanetakis, 2013). Combinations of different viruses can cause similar symptoms, making diagnosis difficult. For example, blackberry yellow vein disease is caused by virus complexes with at least a dozen viruses that can contribute to this disease. With one or two exceptions these viruses are symptomless in single infections in blackberry. Similarly, strawberry decline is caused by a complex of two to seven viruses. 

A plant infected with just one of these viruses may not exhibit symptoms; however, when multiple viruses are present, the disease manifests. These complexities highlight the importance of laboratory testing for an accurate diagnosis