No silver bullet to mitigate co-infection with the ToBRFV virus.

Pepino mosaic virus (PepMV) is present in many tomato-producing countries, while the relatively new tomato brown rough fruit virus (ToBRFV) is becoming more widespread. It is therefore possible for tomatoes to be infected with PepMV, ToBRFV, or a combination of both. It is therefore important to understand the best way to protect plants and to observe whether the order of infection with the virus creates differences in symptoms or expression. This article explains the mechanisms underlying infection by different viruses.

Viruses can have different effects on each other, and these effects are not always the same. There are three different types of interactions that can occur between two viruses:

1. Synergy: The two viruses help each other and the symptoms of both viruses are stronger.

2. Antagonism: one of the viruses becomes predominant and the effects of the other are reduced.

3. Neither virus affects the other.

In some cases, ToBRFV is detected together with other viruses such as PepMV, Tomato Bronzing Disease Virus (TSWV), Tomato Mosaic Virus (ToMV), etc. It has been observed that symptoms on leaves may be more pronounced when ToBRFV infection is followed by PepMV infection. This is probably applicable to other viruses such as TSWV or tomato spoon yellow leaf virus (TYLCV).

For all of these viruses, it is unclear whether these more pronounced symptoms are a true synergy or whether they are due to other stressors, such as a suboptimal growing environment for the plant.

ToBRFV can be easily diagnosed, but even when ToBRFV is detected, we will still need to look for other viruses present in the plant, as they may be causing some or all of the visible symptoms.

No silver bullet to mitigate co-infection with the ToBRFV virus

Co-infection with aggressive viruses is a major challenge, as any uncontrolled infection will reduce yields. Growers will need to adopt and maintain high levels of hygiene practices to maximize the number of productive plants and minimize ToBRFV infections until the end of the crop cycle.

Article Source: Co-infection with tomato brown rough fruit virus (ToBRFV) and Pepino mosaic virus (PepMV) (bayer.com) Read more articles related to ToBRFV on this site.  It is infomative and important New Zealand growers are prepared if ToBRFV enters NZ.