July 2021 - 7

New research seen on Reflex's crop safety on vegetables
By Dean Peterson
VGN Correspondent
Reflex (fomesafen) has a 24C label
in several states for certain vegetables.
With Reflex's ability to control warm
season broadleaf weeds like pigweed
and lambsquarters, Purdue University
is evaluating crop tolerance in pursuit
of a 24C label for Indiana, said Stephen
Meyers, Purdue University assistant
professor of weed science. Meyers spoke
on Purdue's fomesafen research at the
Indiana Horticulture Conference and
Expo, held virtually in 2021.
Purdue researchers looked at Reflex at
1x, 2x, 3x and 4x rates. This correlated to
rates of 16 ounces, 32 ounces, 48 ounces
and 64 ounces per acre for pumpkin,
summer squash, winter squash and
bell pepper, and rates of 12 ounces, 24
ounces, 36 ounces and 48 ounces per
acre for watermelon.
Watermelon leaves had minor injury
at the 1x rate at two locations two
weeks after transplant. The amount of
injury gradually faded and was hardly
noticeable six weeks after transplant.
" Injury was temporary and did not
reduce the number of fruit or yield, "
said Jeannine Arana, Purdue University
graduate research assistant. Arana also
spoke at the conference.
Both winter squash and bell peppers
had a moderate level of injury at the
Summer squash had inconsistent results in Purdue University's trials. The 1x rate of
Reflex (fomesafen) was inconsistent in causing enough injury to reduce plant height
and yield. Photos: Dean Peterson
1x rate two weeks after transplant, and
hardly any visible damage at six weeks.
Yields were similar between the 1x and
nontreated plots.
In summer squash, the 1x rate
sometimes caused enough injury to
reduce plant height and yield. " Summer
squash had inconsistent results, " Arana
said.
Pumpkin's emergence was reduced by
about one fourth at the 1x rate, but the
amount of total fruit and marketable
fruit were only slightly decreased.
" The 1x rate reduced emergence, but
didn't have an effect on yield, " Meyers
said.
The two pumpkin cultivars in
the study did respond differently to
treatment. When adopting any new
practice, including the use of an
additional herbicide, Meyers suggested
that growers not make whole farm
changes in the first year. Growers should
test a small portion of their pumpkins in
the first year to ensure crop safety in the
cultivars they grow.
With the exception of summer squash,
" the 1x rates resulted in minimal injury
at two weeks after planting, " Arana
said, and didn't affect the yield of
watermelon, pumpkin, bell pepper or
winter squash. The 2x, 3x, and 4x rates
Jeannine Arana, Purdue University graduate
research assistant, is part of the school's
efforts to study Reflex's (fomesafen) ability
to control warm season broadleaf weeds
like pigweed and lambsquarters.
showed progressively more damage until
it became very severe.
Purdue's trials will be repeated in
2021. Growers interested in using Reflex
should consult their state pesticide
regulatory office, Extension service, or
Syngenta representative to ensure it is
registered and to secure the applicable
label. VGN
GREENHOUSES
ANY CLIMATE,
ANY CROP
FOR OVER
40 YEARS
GROWSPAN HAS
BEEN HELPING
GROWERS
ENERGY-EFFICIENT DESIGNS
ENVIRONMENTAL CONTROL
EXPERT CONSULTATION
IN-HOUSE SERVICES
www.growspan.com
877.835.9996
VGN | JULY 2021 | 7
http://www.growspan.com
July 2021

Table of Contents for the Digital Edition of July 2021
