“There is a risk that this virus has already been introduced here in Brazil…”
Alice Kazuko Inoue Nagata is a researcher at Embrapa Hortaliças, graduated in agronomy from the University of Brasília, with a M.Sc from the University of Hokkaido and a Ph.D from the University of Brasília.
The Tomato Brown Rugose Fruit Virus (ToBRFV) was recently detected in Argentina. This virus is spreading around the world. With the detection of the virus in Argentina, the chance of it being introduced in Brazil is high.
The virus causes varied symptoms of chlorosis, mosaic, and deformation in tomato leaves. On fruits, it can cause yellowish or brown spots and roughness. This can harm production; if the fruits show strong symptoms, they cannot be sold.
The virus is transmitted easily by contact, hands, and equipment. It can also be transmitted by seeds and by some insects. Brazil must adopt strict measures to prevent the entry of ToBRFV. The first measure should be controlling the quality of tomato seeds, as most of them are imported. We must make sure that imported seeds are produced in regions where the virus does not occur and monitor the quality of these seeds.
As the virus is transmitted by contact, it is important to ensure that fruits from infected plants in Argentina do not enter Brazil for consumption. If a farmer touches the fruit, they can contaminate their hands, and the virus can reach the tomato plants and multiply.
The good news is that hybrid cultivars are being developed with resistance to ToBRFV infection. These seeds will be available soon in Brazil. This is what seed companies guarantee.
If the virus is introduced somehow and its distribution is restricted, it is still possible to eradicate the plants and prevent further spread.
The analysis of plants in search of virus symptoms should not be done only in the States bordering Argentina, as we do not know how the virus entered that country. There is a risk that this virus has already been introduced here in Brazil.
Identifying potential farms with infected plants, performing confirmation tests and, in the case of positive results, performing isolation procedures, destroying plants and sanitizing work equipment may result in successful eradication of the virus.
Identification of infected plants is not easy. Other viruses can cause similar symptoms, in addition to the interference of other factors in the development of symptoms, such as the presence of pathogens (including other viruses), the nutritional status of the plant, cultivar, temperature, insect damage, etc. Currently, the most worrying viral diseases for farmers are Tomato Spotted Wilt Virus (TSWV), Geminivirus, Tomato Chlorosis Virus (ToCV), and Potato Virus Y (PVY).
Tomato Mosaic Virus (ToMV) is a disease caused by a virus of the same family as the ToBRFV, but its occurrence in Brazil is low. The symptoms of this disease are similar, but the main differences are the capacity of the ToBRFV to cause symptoms of roughness and necrosis in the fruits and to be able to infect cultivars with resistance to Mosaic (ToMV).
All this monitoring and eradication efforts will be very worthwhile, considering the damage that this virus causes and the experience reported by farmers in other countries.