July 2022 - 9

GLVPN VEG CONNECTIONS
of thrips from outside. Check
sticky cards every week and record
the number of thrips captured to
monitor population levels and inform
management decisions.
Spray insecticides in the morning,
Figure 5. Weeds within and between high
tunnels that can harbor both the insect and
the virus.
or greenhouses have the potential
to host both the insects and the
pathogens they transmit. Remove the
weeds and leave the structure open
throughout the winter if possible.
Prepare for Next Year
Variety selection can be key for
managing TSWV. If possible, select a
tomato variety that is resistant to the
virus.
Look at your insecticide regime and
be sure that you are rotating products.
Thrips develop resistance quickly to
insecticides. It may be necessary to
invest in some different products to
break the thrips life cycle. Be sure that
you refer to the Insecticide Resistance
Action Committee (IRAC) code.
These codes have been established,
in part, for growers to easily select
chemistries that have different modes
of action (the way it works to kill the
pest). To reduce the development of
resistance, do not make more than
two applications of the same product
in a row. Be sure to check label
requirements in your state.
Consider incorporating a beneficial
organism to prey on the soil-dwelling
stages of thrips. This should be
considered in the off-season, because
it will take time to find a supplier
and determine ordering and shipping
deadlines. You should plan to
incorporate these organisms early in
the season.
Two commonly available options
include predatory soil-dwelling
mites (Stratiolaelaps scimitus) and
entomopathogenic nematodes
(nematodes that eat insects,
Steinernema spp.). Chemistries such
as novaluron, spinosad, tolfenpyrad
and acetamiprid applied in the soil as
a drench or drip are compatible with
the predatory mite species. Bifenthrin,
imidacloprid and lambda-cyhalothrin
have been reported as non-toxic and
safe to use with entomopathogenic
nematodes. Various suppliers of
beneficial insects have an interactive
tool on their websites to look at the
impacts of a chemical product on the
beneficial organism.
Reflective mulches can reduce
TSWV infection by repelling thrips.
During the Growing Season
Monitor for the presence of thrips
by placing yellow sticky cards just
above the crop canopy (Figs. 6 and
7). Place 1 sticky card per 1,000
square feet, as well as near doors and
air vents to monitor the movement
when thrips are most active. Five-day
insecticide application intervals are
more effective than 7-day intervals
in reducing thrips infestation.
Follow a rotation plan when
applying insecticides to prevent the
development of resistance.
Follow the label closely. Many
products kill the insect by coming into
contact directly so adequate coverage
and rates of application are crucial
to get the most out of a product.
If possible, apply insecticides with
equipment that produces very small
spray particles that will penetrate
foliage and flowers to provide the best
coverage. Note: Some insecticides may
damage certain plants, so read and
follow all label instructions.
Extremely Effective Post
Emergent Herbicide
¬ACTIVE INGREDIENT - 15.9 % Phenmedipham
¬PROVIDES Control of Broadleaf Weeds in
Spinach (grown for processing and seeding)
and Red Garden Beets.
¬NEW FIFRA 2(ee)* Recommendation
(AZ, CA & TX)
Offers Application Window Flexibility
Now Available in One Gallon Jugs!
Byron DuBois of Springbrook Farms, Pittsgrove New
Jersey, uses Spin-Aid®
Herbicide on all of his 500 acres of
Figure 6. Several thrips captured on a
yellow stick card. Photo: J. P. Sanderson,
Cornell University.
processed spinach. " I have been using Spin-Aid as long
as I can remember. " Weeds commonly seen in the South
Jersey fields are Lambsquarters, Pigweed and Chickweed.
" I am a real stickler about getting early control of weeds.
If weeds get out of control, we need to hire a hand weed
crew, which is costly and difficult to find. As soon as I
see weeds emerging, I do my first application of Spin-Aid
at 3 pints per acre. " Byron follows up 7-10 days with a
second 3 pint per acre application to make sure he gets
any additional weeds that emerge; after that, the plant
canopy is wide enough to fight off any other ones that
might appear.
Figure 7. Close up of adult thrips
captured on a yellow sticky card. Photo:
John Obermeyer, Purdue University.
Protect plants early, when they are
young and most vulnerable, which is
also when thrips populations tend to
be lower and you have a better chance
of getting them under control.
Continue to manage weeds. They
can be a continuous source of pests
(the insects and the virus) during
the growing season, either between
planting dates or even between
applications of a chemical.
If infection rates are low and it is
early in the season, it is advantageous
to remove infected plants to reduce
the spread of the virus.
If feasible, install exclusion netting.
The number of thrips entering a
greenhouse may be greatly reduced
by covering the doors and air intakes
with a fine mesh (400 mesh) cloth.
Finally, TSWV can be difficult
to diagnose. If you are unsure, be
sure to get an official diagnosis. The
diagnosis may be Impateins Necrotic
Spot Virus (INSV). This cousin of
TSWV has a very similar biology and
management options.
In any case, watch out for
symptoms of TSWV in your
greenhouse tomatoes this year. VGN
Moves Water and Chemicals
Into The Rootzone
¬PROVIDES Uniform Penetration and
Lateral Movement of Water
¬ENCOURAGES Improved Rooting and
Nutrient Uptake
¬ENHANCES Initial Wetting and
Subsequent Rewetting of Soils
¬IMPROVES Distribution and Effectiveness
of Soil Applied Chemicals
¬SAVES WATER - Reduces Irrigation
Requirements by Up To 25%
Other Quality Products Offered From Belchim USA
* See complete 2ee Recommendation prior to use.
All products are not registered in all states.
Ask your Belchim representative for current registration status.
Integrate is a registered trademarks of
Belchim Crop Protection USA, LLC.
2751 Centerville Road | Suite 100
Wilmington, DE 19808
Phone: 855-445-7990 | www.belchimusa.com
info.usa@belchim.com
VGN | JULY 2022 | 9
http://www.belchimusa.com
July 2022

Table of Contents for the Digital Edition of July 2022
