Botanigard a biopesticide from Certis, containing the fungus Beauveria bassiana, has been granted CRD approval for the control of whitefly (Trialeurodes vaporariorum) in a range of protected crops.
Growers of strawberries, aubergines, courgettes, squash, cucumbers, melons, tomatoes, sweet peppers, chillies, ornamentals and nursery fruit trees will all benefit from this new addition to the armoury, which has zero harvest interval and no maximum residue level (MRL).
Dr. Dave Chandler, Principal Research Fellow at Warwick University, is a specialist in biological pest control and integrated pest management (IPM) and has been working with Botanigard for some time.
"We've found this particular strain of Beauveria bassiana to be effective when used correctly, because it has a comparatively high spore count," he explains.
Beauveria bassiana is a fungus that occurs naturally in the soil. Dr. Chandler explains how it works on soft-bodied insects as a biopesticide. "The fungus produces spores which stick to the insect’s cuticle and germinate. Its hyphae penetrate the cuticle and continue to grow inside the insect, eventually overwhelming its immune system and causing death to occur after five to seven days."
Because Botanigard contains a living organism, there are a number of things growers need to be aware of. "It’s affected by temperature and humidity, with optimum conditions for sporulation between 20 to 30°C and 70% relative humidity, so growers will need to pay attention to product storage because excessive heat can kill the spores," he says. "Achieving good spray coverage is also critical for optimum control."
Botanigard isn't a stand-alone treatment, it won't give a fast knock-down of whitefly populations and it should therefore be used as part of an IPM solution, explains Dr. Chandler.
"Botanigard provides a useful second line of defence behind front-line predators and parasitoids and it's important for growers to develop their own systems of using them.
“We'll be relying on more of these types of products with the number of available pesticides continuing to decline and resistance problems on the increase."
Certis' Alan Horgan advises growers to use Botanigard alongside Eradicoat (maltodextrin) as part of their IPM strategy. "This approach targets all stages of the whitefly lifecycle, with Botanigard effective on the first to fourth larval stages, and Eradicoat controlling the puparia and eggs.
“This strategy results in a very robust control option,” he adds.
"This is good news for British growers. It's important that they have access to this technology which has been available to growers in the USA and mainland Europe for some time.”