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PI(s): H. Reissig, A. Agnello, J. Nyrop,
Department of Entomology, NYSAES, Geneva, NY 14456
COOPERATORS: D. Breth, Area IPM Specialist,
Cornell Cooperative Extension Program, J. Carroll, Fruit IPM Coordinator,
Cornell University.
Type of Grant: Pheromones; biorationals;
microbials; conventional pesticides
Project location(s): Results from this
project can be applied throughout the Northeastern United States and
also apple production regions in the midwestern United States.
Abstract: Recently, apple growers in western
NY have suffered severe financial losses from unacceptable levels of
fruit infestation by internal lepidoptera larvae. If this new crisis
is not solved quickly, it could hasten the decline of this already beleaguered
industry. Furthermore, if growers are forced to use harsh insecticides
and revert to applying sprays on a calendar basis at 14-day intervals
throughout the season to control these pests more than 30 years of IPM
research and implementation may be subverted. The objectives of this
project were : (1) Provide apple growers with effective ways of controlling
internal fruit feeding Lepidoptera that are consistent with and integral
to existing apple pest management systems. (2) Develop better understanding
of internal Lepidoptera distribution in time and space, and susceptibility
to insecticides so that control tactics can be made more robust and
effective. This year's studies showed that currently available technology
for timing insecticide applications against the summer generations of
oriental fruit moths, developmental models based on heat unit accumulations
and trap catch threshold levels are not adequate for use in NY apple
orchards. Warrior, a synthetic pyrethroid insecticide, which is toxic
to beneficials, was the most effective insecticide in protecting fruit,
but Avaunt (Indoxacarb) provided similar levels of control. Laboratory
bioassays were conducted to compare the susceptibility of field populations
of oriental fruit moth in orchards in western NY to a standard organophosphate
insecticide, Guthion (Azinphsomethyl) that has been widely used in the
past. These studies indicated this pest has developed low levels (about
2-fold) to organophosphates. However, Imidan, another widely used standard
organophosphate insecticide, provided adequate control of fruit damage
from internal lepidoptera in 9 out of 10 plots in different orchards
when it was applied at high rates. Mating disruption alone using sprayable
formulations of oreintal fruit moth pheromones did not provide adequate
control of summer damage in orchards that were subjected to high pressure
from this pest. However, an integrated program utilizing sprayable pheromones
and two initial applications of Avaunt provided slightly better control.
Periodic sampling of fruit throughout the summer in various management
programs showed that damage was very low from late July through August.
Generally, higher levels of damage were observed in all plots when fruit
was evaluated in mid-late October, although fruit infestation levels
were generally below 2% at harvest in most of the treatments. The overall
results of this study suggest that mating disruption, and standard organophosphate
insecticides as well as newer selective insecticides can provide adequate
control of internal lepidoptera in problem orchards in western NY. In
the future, additional work should be done to determine the optimum
seasonal timing of insecticides or even pheromones (particularly sprayable
formulations) for management of internal lepidoptera. Different management
programs including integrated programs utilizing insecticides and mating
disruption that are designed to be cost effective and IPM compatible
should be compared in large scale tests in grower's orchards throughout
western NY. It would also be useful if practical monitoring programs
for detecting fruit infestation during the season could be developed
so that growers or consultants could monitor orchards periodically to
determine when and if control measures are necessary. Finally, additional
monitoring of susceptibility of field populations of oriental fruit
moths and perhaps codling moth to commonly used classes of compounds
such as organophosphates and pyrethroids should be continued. These
studies are necessary to determine if there are regional patterns of
susceptibility differences throughout apple production regions in western
NY and to monitor any changes during the future.
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