Strawberry and Raspberry Pest Management in Wisconsin

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Raspberry Disease Management
Cane diseases, Verticillium wilt, and gray mold are the more important
fungal diseases that affect raspberries in Wisconsin. Viral diseases, such
as crumbly berry and mosaic, are apparently widespread in Wisconsin
and may be the limiting factor for raspberry production in older
plantings. Accurate diagnosis of a disease problem is essential before
effective disease management can be implemented.
Bear in mind that several important diseases of raspberry, including
Verticillium wilt and viral diseases, cannot be controlled with
fungicides. While certain cultivars of raspberry are notably susceptible
to some diseases, cultivars that are highly resistant to the most
important diseases in Wisconsin have not been identified. These facts
underscore the importance of sanitation and cultural practices in
managing diseases of raspberry.
FUNGICIDE UPDATE In recent years there have been several changes in fungicides registered
on raspberry and other brambles. Always read labels carefully to be
certain that the product formulation is registered on the type of
bramble or “caneberry” crop you wish to treat.
Myclobutanil fungicide previously was sold for use on fruit crops under
the trade name “Nova” and now is sold under the trade name “Rally.”
The formulation is identical, and use recommendations on strawberry
and raspberry, including rates and timing, have not changed. Growers
may continue to use existing stocks of Nova according to that product’s
label. Myclobutanil is especially effective in controlling rust diseases of
brambles.
Azoxystrobin fungicide previously was marketed to strawberry and
raspberry growers under the trade name “Quadris” and now is
marketed as “Abound.” Existing stocks of Quadris may be used on
strawberry and raspberry only if you hold the original label listing these crops.
Quadris is still labeled and marketed for use on many vegetable crops,
but newly purchased Quadris may not be used on strawberries or
raspberries. Abound is effective in controlling several diseases of
raspberry, including anthracnose, spur blight, leaf spot, rusts, and
powdery mildew.
Abound and Quadris both are highly toxic to certain apple varieties,
especially McIntosh and related varieties. Even a small amount of
Abound or Quadris, such as spray drift or spray tank residue, is toxic to
apple leaves and fruit. Therefore, these products are not recommended
for berry growers who also grow apples.
Orbit (propiconazole) is an older fungicide that only recently has been
labeled for use on strawberry and raspberry. Propimax is another brand
of propiconazole; it is registered on raspberry and other “caneberries”
and “bushberries,” but not on strawberry. Orbit and Propimax are in the
same class of fungicides as myclobutanil (Nova, Rally). On raspberry
these fungicides are labeled for control of Septoria leaf spot, rusts, and
powdery mildew.
Various phosphorous acid products (also called phosphites or
phosphonates) are registered on fruit crops. These are related to
fosetyl-aluminum (Aliette), which has been used to control
Phytophthora pathogens of small fruits for years. On raspberry, these
products are used to control Phytophthora root rot. Because these