Effects of SITKO insecticide for control of Two Spotted Spider Mites on strawberry in North Carolina, 2016.
Biological Applied Research Inc.,
Dr. James Driver
Raleigh, NC 27603
Objective: The trial was conducted at the Biological Applied Research Inc., research farm in Elm City, NC to evaluate product efficacy on Two Spotted spider mite control. The product tested was SiTKO, manufactured by Growth Products, a propietary product containing phosphite, silicate and salicylic acid as compared to a commercial standard and control.
Method: The soil type in the research field was a sandy loam. Plots were established on 8-in. high, 30-in. wide, black VIF, 1.25-mil plastic-mulched beds on 60-in. row centers. Plots were established with plug plants on 10 Oct 15. Plot length was 12-ft long and consisted of two staggered rows containing 24 plants. Treatments were randomized in four replicated complete blocks. There were 5treatments including an untreated check. Product applications were applied on a weekly basis starting 24 Mar through 6 May for a total of 7 sprays. Application start date coincided with 10% bloom. Deliver 50 gal/A at 60 psi through three-nozzles spaced 19 in. apart on the boom. Plots were harvested weekly beginning 14 Apr through 6 May for a total of 5 harvests.
Results: Fruit harvest evaluations included marketable, diseased, and cull fruit (undersized, misshapen) were determined by number of berries and weight of each grade.
The mite count was highest in the untreated check and treatment 4 with 397 and 226 total mites, respectively. Treatments 2 (SiTKO 1 Qt. /A), 3 (SiTKO 2 qt/A), and 5 (M-PEDE 2 gal/A) had lower mite counts of 135, 137, and 170, respectively. Total marketable yield was greatest in treatment 5 with 5,437.9 total marketable weight. Treatments 2, 3, 4, and the untreated check all had similar marketable yields of 3,982.1, 3,632.1, 3,391.2, and 3,172.7, respectively.
Percent marketable yield was highest in treatment 5 and 2 with 53.4% and 44.8% marketable yield, respectively. The lowest % marketable yield was harvested from the untreated check with 28.8%. Treatments 3 and 4 both had adequate % marketable yield of 36.5% and 37.9%, respectively. The untreated control had the most mites, highest cull weight, lowest % marketable yield, and low total yield weight.
Treatment 2 and 3 also show promise with low mite counts, low cull weights, adequate % marketable yield, and low % cull yield.
Control of Twospotted Spider Mites on Strawberry Total Mite Count
Twospotted Spider Mite Strawberry Trial, 2016
Application March – May, 7 sprays per product, Delivery 50 gal per acre
Biological Applied Research Inc., Raleigh, NC