Q. I have been hearing about a new fungicide to control late
blight on tomatoes called Serenade®. Can you tell me more about it?
A.Seren key diseases of
fruits, vegetables and ornamental plants, including late
blight on tomatoes. Biofungicides such as Serenade® are
made from beneficial microorganisms such as bacteria and
fungade® is a biological fungicide (biofungicide) that
has a broad label to suppress and control manyi. The active ingredient in Serenade® is the QST 713
Strain of Bacillus subtilis.
Serenade® has multiple modes of action to protect plants
from pathogens. It inhibits pathogens from infecting
leaves by preventing them from attaching to the leaf in
the first place. If pathogens do manage to attach to a
leaf, Serenade® outcompetes them for space on the leaf
and inhibits their ability to absorb nutrients. It also
destroys their ability to reproduce.
Red tomatoes at the produce market
Serenade® is approved for organic production by the
Organic Materials Review Institute (OMRI). It can be
used up to the day of harvest. Like most fungicides,
Serenade® is most effective when used to prevent
disease; it is not an effective “cure” once late blight
gets started. The label recommends application every
seven days, and it can be applied more frequently when
disease pressure is high or when environmental
conditions favor rapid disease development.
LATE BLIGHT ON TOMATOES
Late blight has been detected throughout western
Pennsylvania again this year, including Allegheny
County. Daytime temperatures between 70-80 degrees and
nighttime temperatures between 50-60 degrees favor late
blight, as does moisture on the foliage from rain, fog,
dew or overhead watering.
OTHER LATE BLIGHT TREATMENTS
If you are concerned about your tomato or potato crop,
it is time to apply fungicides to protect them from late
blight. In addition to Serenade®, copper-based
fungicides are available for organic gardeners.
Conventional gardeners can use fungicides that contain Daconil (chlorothalonil) to protect susceptible crops
from late blight.