Isaria fumosoroseus (PREFERAL® WG)

PREFERAL® WG is a biological insecticide that provides excellent control of whiteflies in protected crops of tomato, cucumber and ornamentals. It contains spores of the naturally-occurring strain of the fungus Isaria (=Paecilomyces) fumosoroseus strain Apopka 97 and is highly efficient against all whitefly stages (egg, larva, pupa and adult).

After germination of the spore, the fungus penetrates and proliferates inside its host.
A white-grey colored mycelium will be visible on the outside of the insect cadaver.
Under suboptimal conditions, the mycelium will not become visible; however, infected hosts are recognized as deformed insects which turn brown.


PREFERAL® WG contains 2 x 109 CFU/g and issupplied per 500 g in a plastic reclosable container.


Only available in Belgium, Netherlands, France, Norway, Sweden and Finland.


Local regulations may impose restrictions on the use of this product. Contact your authorities or contact your Biobest consultant.
We produce our products and solutions for professional growers in horticulture.

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