Garlic-Thrips

Includes

Onion thrips (Thrips tabaci)
Western flower thrips (Frankliniella occidentalis)

Pest description, crop damage and life history

See:

Adults overwinter in trash, under bark, and in other protected places. Adults become active in the spring and lay eggs in the tissues of plants with one end of the egg protruding slightly. The eggs hatch into nymphs, which begin feeding in flowers, buds, and leaves. When mature, nymphs drop to the ground and molt into adults. Under favorable conditions, a life cycle may require only 2 weeks.

Pest monitoring Thrips tend to have clumped distribution both through the field and on individual plants. Thrips are active and are dispersed readily by wind. White or yellow sticky traps are useful to monitor for thrips flights. On onions, an action threshold of one to two per leaf or 30 per plant is suggested. Treatment usually is not necessary on seedlings, because most plants recover from thrips injury.

Management-cultural control

Sanitation is very important. Volunteers should be rogued out. Cloves used for planting should be free of contamination. Thrips populations tend to build up on weeds. Cultivating nearby weedy areas early in the year reduces the potential for a thrips problem when the weeds begin to dry out. Cultivating weedy areas after plant emergence may increase thrips problems.

Management-chemical control: HOME USE

  • acetamiprid
  • azadirachtin (neem oil)-Some formulations are OMRI-listed for organic use.
  • Beauvaria bassiana-Some formulations are OMRI-listed for organic use.
  • cyhalothrin
  • deltamethrin
  • gamma-cyhalothrin
  • insecticidal soap-may require several applications-Some formulations are OMRI-listed for organic use.
  • kaolin-Applied as a spray to foliage, it acts as a repellent to some insect pests. Some formulations are OMRI-listed for organic use.
  • lambda-cyhalothrin
  • malathion
  • permethrin
  • pyrethrins-Some formulations are OMRI-listed for organic use.
  • spinosad -Some formulations are OMRI-listed for organic use
  • zeta-cypermethrin

Management-chemical control: COMMERCIAL USE

  • abamectin (Agri-Mek) at 0.009 to 0.019 lb ai/a. PHI 30 days. REI 12 hr. Retreatment interval 7 days. Limit 2 sequential treatments. Do not exceed 0.056 lb ai/a per season.
  • acetamiprid (Assail 30SG) at 0.094 to 0.15 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 7 days. Limit 4 treatments per year. Do not exceed 0.6 lb ai/a per season.
  • borate complex (Prev-Am Ultra) apply as 0.8% solution. Spray for complete coverage. REI 12 hr. Retreatment interval 7-10 days. OMRI-listed for organic use.
  • Burkholderia spp. (Venerate XC) at 1 to 8 quarts/a product. PHI 0 days. REI 4 hr. Suppression only. OMRI-listed for organic use.
  • Chenopodium ambrosioides extract (Requiem 25EC) at 1.5 to 3 quarts formulated product per acre. REI 4 hr. OMRI-listed for organic use.
  • Chromobacterium subtsugae (Grandevo) at 0.6 to 0.9 lb ai/a. PHI 0 days. REI 4 hr. OMRI-listed for organic use.
  • cyantraniliprole (Exirel) at 0.088 to 0.133 lb ai/a. PHI 1 day. REI 12 hr. Retreatment interval 5 days. Limit 6 treatments per year. Do not exceed 0.4 lb ai/a per year. Suppression only.
  • cypermethrin (Holster) at 0.08 to 0.1 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.5 lb ai/a per season. Adjuvants such as MSO or COC increase efficacy.
  • deltamethrin (Delta Gold) at 0.018 to 0.028 lb ai/a. PHI 1 day. REI 12 hr. Retreatment interval 5 days. Do not exceed 0.112 lb ai/a per season.
  • dinotefuran (Scorpion 35SL) at 0.135 to 0.18 lb ai/a foliar; 0.225 to 0.27 lb ai/a soil. PHI 1 day. REI 12 hr. Do not exceed 0.383 lb ai/a per crop season.
  • gamma-cyhalothrin (Declare) at 0.01 to 0.015 lb ai/a. PHI 14 days. REI 24 hr. Do not exceed 0.12 lb ai/a per season. Use of a COC or nonionic surfactant improves performance.
  • GS-omega/kappa-Hxtx-Hv1a (Spear Biological Insecticide) at 0.05 to 0.4 lb ai/a. PHI 0 days. REI 4 hr. Do not exceed 2 lb ai/a per year.
  • imidacloprid (Admire Pro) at 0.5 lb ai/a soil. PHI 21 days. REI 12 hr. Do not exceed 0.5 lb ai/a per season
  • lambda-cyhalothrin (Warrior II) at 0.02 to 0.03 lb ai/a. PHI 14 days. REI 24 hr. Retreatment interval 5 days. Do not exceed 0.24 lb ai/a per season. A silicone surfactant increases efficacy.
  • malathion (Malathion 8) at 1.0 to 1.56 lb ai/a. PHI 3 days. REI 24 hr. Retreatment interval 7 days. Limit 3 treatments per year. Do not exceed 1.56 lb ai/a year.
  • oxamyl (Vydate L) at 0.5 to 1 lb ai/a. PHI 14 days. REI 48 hr. Retreatment interval 7 days. Do not exceed 4.5 lb ai/a. WA only. SLN WA-000018.
  • permethrin (Loveland Permethrin) at 0.15 to 0.3 lb ai/a. PHI 1 day. REI 12 hr. Do not exceed 0.8 lb ai/a per season. Retreatment interval 10 days.
  • spinetoram (Radiant SC) at 0.047 to 0.078 lb ai/a. PHI 1 day. Retreatment interval 4 days. Do not exceed 0.234 lb ai/a per season. Limit 5 treatments per season.
  • spirotetramat (Movento) at 0.08 lb ai/a. PHI 3 days. REI 4 hr. Do not exceed 0.16 lb ai/a per season. Retreatment interval 7 days.
  • spinosad (Success, Entrust SC) at 0.06 to 0.12 lb/a. PHI 1 day. REI 4 hr. Retreatment interval 4 days. Do not exceed 0.45 lb ai/a per crop or make more than 5 application per year. Thrips suppression. Entrust SC is OMRI-listed for organic use.
  • zeta-cypermethrin (Mustang) at 0.0375 to 0.05 lb ai/a. PHI 7 days. REI 12 hr. Retreatment interval 7 days. Do not exceed 0.25 lb ai/a per season.