Pest Control by Vacuum Removal
by Phyllis Weintraub
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the state of agriculture today is highly dependent on chemicals
to control pest species, and that many of these species exhibit
resistance to pesticides, is axiomatic. New and innovative
means of controlling pest populations are being explored,
albeit slowly. We have designed and tested a new field-scale
vacuum machine.
| Arrows indicate direction of air flow.
A - housings for impellers; B - cover of exit portal for
insects an debris; C - frame to raise and lower suction
inlet with respect to outlet air jets; D - junction point
to raise and lower unit (D=male; F=female); E - suction
inlet; F- outlet air jets. |
This schematic shows the unique design: two blowers are
directed perpendicularly to, and on either side of a bed of
plants, to dislodge insects; a vacuum located above encompasses
the entire area between the blowers to immediately remove
the insects that are dislodged. Walklate (1994) showed, using
a computer simulation, that an outlet jet of air blowing at
30m/sec affects a much greater area than a suction inlet of
the same size and airflow. The vacuum unit can be raised or
lowered to accommodate plant height. Furthermore, the unit
can be completely raised above the plants by hydraulics at
the end of a row for turning. Insects are exhausted through
the impeller blades and thus even the smallest are completely
destroyed
 Since
1991, trials have been run on celery, tomato, potato and melon
crops to evaluate the efficacy of the vacuum unit for use
in insect pest management. Efficacy was evaluated by field
observations, yellow sticky traps, hand vacuum sampling before
and after treatment, and by taking leaf samples. All insects
evaluated were effectively removed by the vacuum unit; typically,
population reductions of 50 - 75% were achieved with agromyzid
leafminers, whiteflies, leafhoppers, and aphids. In some trials,
notably, whiteflies, reductions were achieved which lasted
from week to week (Weintraub et al., 1996; Weintraub and Horowitz,
1999)
| Densities of Whiteflies on Melon. Samples
(1 meter-row) were taken with a hand-held vacuum unit
immediately before and after the field was vacuumed, and
from the non-treated control and insecticide-treated plots.
|
One concern is that there might be extensive physical damage
to the plants as a direct result of the tractor and blowing/vacuuming
actions on the plants, or to the yield (as in potato crops)
as a result of soil compression. Visual observations and comparison
of yield results have shown that the plants are not significantly
damaged. Further, there is no observable increase in plant
diseases (such as Phytophthora).
While we do not envision that this form of mechanical control
will ever be the sole means of insect control in a field situation,
we can foresee its benefits when used in insect pest management
programs. Predator/parasitoid complexes usually can not overcome
high pest populations. However, by reducing insect populations
first by field vacuuming and then immediately releasing biological
control agents, efficacy may be greatly improved. Field vacuuming
is likewise fully compatible with chemical control measures,
reducing pest populations either instead of a regular pesticide
treatment or immediately before application.
Literature Cited:
- Walklate, P.J. 1994. Aerodynamic methods for controlling
insects. Vine Weevil Workshop Conf. Proc., 6 June 1994,
Rochester, Kent, U.K. pp. 1-6.
- Weintraub, P.G., Arazi, Y. and Horowitz, A.R. (1996) Management
of insect pests in celery and potato crops by pneumatic
removal. Crop Protection 15, 763-769.
- Weintraub P.G. and Horowitz, A.R. (1999) Management of
the whitefly, Bemisia tabaci (Genn.), on melon by
pneumatic removal. Ins. Sci. Applicat. 19:173-178.
Additional Information on Mechanical Control:
Weintraub, P.G. and A.R. Horowitz. (2000). Vacuuming Insect
Pests: the Israeli Experience. In, La Lutte Physique en
Phytoprotection. Eds. C. Vincent, B. Panneton and F. Fleurat-Lessard.
pp. 315-324. Editions INRA, Paris. English edition to follow.
Broad mites in the Arava,
Israel
Pest control by vacuum removal
The pea leafminer in Israel
Vectors of phytoplasmas in carrots
Vectors of phytoplasmas
in hybrid Limonium 
Vectors of phytoplasmas in vineyards
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