Oregon Strawberry Commission
Research Progress Report

1994 - 1995


Insect Control Efficacy for Strawberries Treated with
Admire 2F Compared to a Standard Commercial Insecticide
and an Untreated Check


Conducted by
Donald L. Kloft Collins Agricultural Consultants, Inc.
33668 S.W. Bald Peak Road Hillsboro, Oregon 97123


ABSTRACT

Admire 2F insecticide was applied to an established stand of strawberries, at two separate rates, to investigate the potential of the material in controlling mites which commonly feed on strawberries. Treatments were compared to an untreated check and a commercial standard. One application was made as a directed-band treatment during the early flowering stage of the crop when ten percent of the initial blooms were present.

No phytotoxic effects where noted on any strawberry plant,.for any treatment, on the date of evaluation. No mite populations developed in the trial while in progress. Excellent spittlebug control was noted for the Admire 2F treatments.

MATERIALS AND METHODS

The below listed materials were applied to the crop in a directed-band technique. Application rates are based on the amount of active ingredient, for each test product, applied to the actual treated area as a band.

I. Treatments
 Trt. No.TreatmentRate/Unit
 
 1Untreated--------------
 
 2Admire 2F0.10 lbs. a.i./A
  Sylgard0.50 pts. per/100 gal.
 
 3Admire 2F0.25 lbs. a.i./A
  Sylgard0.50 pts. per/100 gal.
 
 4Metasystox-R.0.50 lbs. a.i./A


The two treatments containing Admire 2F were tank mixed with Sylgard, a silicone based adjuvant, to enhance the penetration of the material into the plants.

II. Test Plot Description and History

Treatments were applied to plots arranged in a randomized completed block design. Plots consisted of one raw of berries. Row spacing was 40 inches, or 3.33 feet between rows. A banded width of only 30 inches or 2.5 feet per row was actually treated. The plots were 25 feet long and the treatments were replicated four times.

The trial was established in a commercial production field of strawberries, Fragaria spp., of the variety Red Gem. The crop was established July 07, 1994 using techniques common for the area. Standard commercial practices of crop maintenance was pe:~formed by the grower/cooperator accept for the application of insecticides prior to or while the trial was in progress.

The test area was irrigated using overhead in-pact sprinklers on the following date at the following rate indicated: 5/23/94 - 4.00 in.

1.47 inches of precipitation fell throughout the duration of the test, as measured and recorded on site with a precipitation monitoring tipping bucket and data recording pod. Excellent ground moisture was present throughout the trial period. The attached air temperature and precipitation record weather data was collected from a NOAA weather station located in Forest Grove, Oregon approximately six miles southeast of the trial site.

Soil at the test site is a McBee silty clay loam according to the local Soil Conservation Service soil maps for the area. A soil characterization analysis performed by Midwest Laboratories indicates the soil is a loam containinqr28% sand, 48% silt, and 24% clay materials with 3.3% organic matter. The soil has a cation exchange capacity of 12.8 meq./100 gm at a pH of 5.4.

The experiment was located in Washington County, approximately six miles north west of Forest Grove, Oregon.

III. Treatment Application

All treatments were applied using a CO2-powered backpack plot sprayer with a banding boom equipped with three D-6 hollow cone nozzles. The nozzle placement and boom configuration placed the spray material directly onto the foliage of each individual row. One nozzle was located directly over the center of the row spraying down into the canopy from above. Two drop nozzles, one located on either side of the row, were positioned such that spray material was directed into the row from either side.

One application timing was made to the test crop. The application was made May 04, 1994 to a healthy stand of strawberries which were at a growth stage of 10 percent initial bloom. The test materials were applied at this time in the attempt to follow common application timing techniques for the area. Metasystox-R had an application restriction where it had to be applied prior to bloom. No mite populations had developed by this time; it was decided to apply and hope for a mite population to build.

The product mixed well with water during the mixing and application procedures with no problems encountered.

Environmental conditions present at the time of application are listed below:


 Date:May 04, 1994
 Air/Soil Temperature (°F):67 / 67 @ 3"
 % Relative Humidity:52
 Wind Direction/Velocity (m.p.h.):West / 0-1
 Sky/Soil Conditions:80% Clouds / Friable
 Soil/Leaf Moisture:Moist / Dry
 GPA/PSI:100 / 40
 Treatments Applied:2, 3, 4


IV. Evaluations

Visual assessment of strawberry plant injury resulting from the application of the test materials was made June 08, 1994.

Attempted mite counts were made by randomly harvesting 20 leaves from plants randomly chosen in each plot. These leaves were run through a mechanical mite brush onto a counting plate and examined under a dissecting scope. Counts were attempted immediately before the application of test materials and again 7, 14, 28, and 35 days after the application.

Meadow Spittlebug, Philaenus spumarius L., counts were taken immediately before the application of test materials and again 7, 14, 28, and 35 days after the application.


RESULTS AND DISCUSS

I. Phytotoxic Effects

  1. No phytotoxic effects were noted on the foliage or fruit for any treatment on the date of evaluation. Good fruit formation was present with no signs of deformities or blemishes attributable to the insecticide treatments.

II. Mite Control

  1. A population of mites did not develop in the trial area during any period the trial was monitored. No mite populations developed in any area of the adjacent commercial field as well.

III. Meadow Spittlebug Control

  1. A good population of spittlebugs was present in the trial area prior to the application of the test materials. Excellent control of the spittlebug infestation was noted in those treatments containing the Admire 2F material. The Metasystox-R treatment had a limited level of control on the spittlebugs present in the plots. Spittlebug ]populations for the entire trial crashed between the May 18, 1994 evaluation and the June 01, 1994 evaluation. No spittlebugs were noted in any treatment during the June 10, 1994 evaluation.

IV. General Discussion

  1. Test results with Admire 2F indicates the potential for excellent spittlebug control when applied to strawberries in a timely manner. The potential use of Admire 2F as a commercial insecticide for an aphid problem looks excellent.