“Do not try to resolve a ToBRFV infection on your own.”

What if your new greenhouse becomes infected with ToBRFV? This happened to the team at British greenhouse horticulture company La Sierra. “At first we thought it was a strong pepino infection, but tapeworm disease was also found,” Nick Ernst recently shared during the British Tomato Conference. He has been working closely with other parties, such as laboratories, seed producers and others in the industry, to overcome this problem as quickly as possible, but he also wants other farmers to learn from their experiences in eliminating the virus. “Do not try to fix the infection yourself.”

NFT and Substrate
The La Serra tomato greenhouse in Throckmorton, England, is special because it combines NFT (nutrient film technologies) with growing tomatoes in substrate. This is done on an area of ​​4 hectares. It is a modern site which is why growers choose the latest LED lighting available for their bulbs.

However, during construction in 2019, not all the lights were available on time, meaning contractors were still busy once the plants were established and growing. “We had strict procedures such as requiring contractors to bring clean clothes, use our own vehicles, and take every measure possible,” Nick recalls.

Later, it is believed that moving employees to another greenhouse may also have caused the infection. “Issues with staff availability and lack of knowledge resulted in us having to move staff to other locations.”

Nick shares his experiences at the British Tomato Conference.

Pepino and rogoz
The reason for this will never be known for sure, but after the first crops were planted in July 2019, farmers began seeing signs of what appeared to be a strong mixed pipino infestation in November 2019 – something that was confirmed by specialist testing. “You can grow through it,” Nick says. But in March 2020, APHA conducted a national survey of tomato growers, and La Serra’s results were strongly positive. “We’ve already had strong pepino and rugus infections.”

The farmers conducted a deep clean-up, burned crops on the site, took samples to test for the virus, and after their results came back negative, began planting again — but by the end of the year, mild symptoms were found in the new crops. More intensive cleaning and disinfection took place, but by the end of the year investigations again confirmed contamination. The company decided to hire a specialist to clean/disinfect the greenhouse in July 2022. This team, equipped with a special kit, has successfully disinfected the virus from other commercial greenhouses in the Netherlands and abroad.

“With this kit, including pumps, extra hoses and everything necessary, we followed the protocol, soaking the structure continuously for several days, using special tools for thorough cleaning under the gutters, as well as treating the screens with specialized equipment,” says Nick. It worked: the virus was never seen again. “We hired the company again this year, and their visit has become standard protocol in our cleaning.”

What can you learn from him?
This doesn’t mean hygiene measures are no longer important – they remain extremely important, as Nick believes resistant varieties are currently the only way. Share your story during British Tomato Conference To let other farmers know what worked and what didn’t work for them. “What can you learn from it? Don’t try to clear up the infection yourself,” he says. “Specialists have the right equipment and can target specific areas,” he explains, adding that he realizes that in the event of an infection, individual business decisions must be made depending on the age of the crop. The longer an infected crop remains in the greenhouse, the greater the viral load at the site.

for more information:
No walk
www.laserra.org.uk