The product, which contains dimethomorph and mancozeb, has new label recommendations for the control of downy mildew (Peronospora destructor) in bulb onions, garlic and shallots and the reduction of white tip (Phytophthora porri) in leeks.
BASF representative Simon Townsend said: "Invader has performed consistently well on all strains of onion downy mildew, including metalaxyl-resistant strains. In trials, it reduced levels of downy mildew from more than 55 per cent of leaf plant affected down to 10 per cent.
"A new label recommendation for Invader, which contains two actives with different modes of action, will be welcomed by allium growers - especially when other fungicides such as straight chlorothalonil and some chlorothalonil formulations will be going this year."
He added that the recommended label rate of 2.5kg/ha for bulb onions, shallots and garlic delivers a full dose of both actives - equivalent to 187.5g ai of dimethomorph per hectare and 1,667g ai of mancozeb per hectare.
"This is more than other mancozeb-containing fungicides and means more robust control," said Townsend. "Invader also has a very useful 14-day pre-harvest interval for bulb onions, shallots and garlic, while all other onion fungicides containing mancozeb have an interval twice as long - 28 days."
In leeks, its pre-harvest interval is 21 days. Invader should be applied in a protectant programme starting before the appearance of disease symptoms or when local monitoring and forecasting indicates a high risk of infection.
Townsend said: "In outdoor bulb onions, shallots and garlic it can be applied up to a maximum total dose of 10kg of product per hectare, equivalent to four applications at its recommended dose of 2.5kg/ha and in leeks up to 6kg of product per hectare, equivalent to three applications at its recommended dose of 2kg/ha."