Peanut Miticide Efficacy Trials
Overview
- Levels of twospotted spider mites were low in our experimental research trials during the 2025 growing season.
- The regular precipitation experienced in 2025 did not favor conditions for mite populations.
- Low numbers of twospotted spider mites were observed in the plots in 2025.
- Field trials to address the management of twospotted spider mites in Oklahoma were established in 2025 at experimental research plots.
- Field trials were conducted during the 2025 peanut growing season to evaluate the efficacy of currently available and experimental miticides with different active ingredients.
- A new Fact Sheet, EPP-7346 Mite Control in Oklahoma Peanut Production, was developed to provide guidance on scouting for mites, recognizing their damage in peanuts, and available miticides with known activity for mite management.
Twospotted Spider Mite Control – Miticide Products
Methods for Conducting Field Experiments
A field trial was conducted at the Caddo Research Station near Fort Cobb to quantify the effect of available and experimental miticides on twospotted spider mite populations and yield (pounds per acre). The soil was classified as a Binger fine sandy loam and had previously been cropped with cotton. Approximately 100 pounds per acre (lbs./A) of a granular fertilizer at 18-46-0 (N-P-K) + 2 lbs./A Sulfur + 1 lb./A Boron was incorporated into the soil on April 28. The herbicide Roundup Power Max (quarts per acre) was also applied on the same date. The herbicide Gramoxone (1 qt/A) + Crop Oil (1 qt/A) was also applied on the field on May 5 at crop pre-emergence. The research trials to evaluate the efficacy of miticides to manage twospotted spider mites were planted on May 12.
The experimental design was a randomized complete block with four blocks separated by a 5-foot-wide fallow buffer. Each plot consisted of four 25-foot-long rows spaced 36 inches apart. Olé, a Spanish market-type cultivar, was planted at the edge of the research station fields to allow irrigation to be shut off, so dry conditions would attract natural mite infestations. Plots were scouted weekly for mite presence following emergence.
Twospotted spider mites from a greenhouse infestation were used to artificially infest the research plots in early to mid-August when natural infestations were not occurring. Four clippings containing 75-100 mites each, one per row, were randomly placed in the canopies of peanuts growing in each trial plot. Irrigation was turned off for four to five days, so mites would not be washed from the peanut plots. Three mite infestations were made on Aug. 5, Aug. 22 and Sept. 5.
Results
The total rainfall during the cropping period (May 12 to Oct. 8) totaled
- 1.13 inches for May
- 4.03 inches for June
- 0.78 inches for July
- 4.58 inches for August
- 3.49 inches for September
- 0.02 inches for October.
Minimum, average and maximum air temperatures were as follows:
- May 12-31: 46.4 ºF, 67.4 ºF and 93.2 ºF
- June: 57.2 ºF, 77.9 ºF and 93.2 ºF
- July: 66.2 ºF, 82.5 ºF and 102.2 ºF
- August: 62.6 ºF, 79.1 ºF and 100.4 ºF
- September: 53.6 ºF, 73.7 ºF and 95 ºF
- October 1-10: 57.2 ºF, 73.9 ºF and 89.6 ºF
The rainfall totals during the 2025 growing season were above normal (30-year average) in June, August and September but below normal in May, July and October. The average monthly temperatures were below normal (30-year average) in May, June, July, August and September but above normal in October. The consistent rainfall experienced in most of the cropping period, coupled with the below-normal temperatures, did not favor mite infestations or population growth. Artificial mite infestations did not take hold due to the rainfall received in August and September at the experimental research plots. Twospotted spider mite pressure was not present even after the three artificial mite infestation attempts. Therefore, miticide applications of available products and experimental chemistries listed in Table 1 were not made. Since no miticide applications were made, yield data were not collected.
| Treatment: Product, rate | Application frequency, interval | Active Ingredient (% Active ingredient) | Mite Life Stage Targeted |
|---|---|---|---|
| Portal 1 pint/A | 2 applications, 14 days | Fenpyroximate (5%) | All life stages |
| Portal 2 pint/A | 2 applications, 14 days | Fenpyroximate (5%) | All life stages |
| Comite II 36 fl oz/A | 2 applications, 14 days | Propargite (69.6%) | Juveniles and adults |
| Vertento 1 fl oz/A | 2 applications, 14 days | Isocycloseram (25.7%) | Not labelled for mites in peanuts, experimental |
| Zeal SC 23 fl oz/A | 2 applications, 14 days | Etoxazole (31.7%) | Eggs and juveniles |
| Hero 10.3 fl oz/A | 2 applications, 14 days | Bifenthrin (11.25%) + zeta-cypermethrin (3.75%) | Juveniles and adults |
| Briagde 2EC 6.4 fl oz/A | 2 applications, 14 days | Bifenthrin (25.1%) | Juveniles and adults |
| Elevest 7.7 fl oz/A | 2 applications, 14 days | Bifenthrin (14.4%) + chlorantraniliprole (9.6%) | Juveniles and adults |
Acknowledgments
Thank you to Michael Pettijohn, Brennan Leighton and Harley Houston of the Caddo Research Station, Maíra Duffeck’s row crop pathology crew and Maxwell Smith for their help and cooperation in establishing and maintaining the field plots for this trial. Thank you to the Oklahoma Peanut Commission and the National Peanut Board for their generous financial support for this research. Special thanks to FMC, Syngenta, UPL and Nichino for providing additional funding and miticide product for use in this trial.