Greenhouse ornamentals-Whitefly

Greenhouse whitefly (Trialeuroides vaporarium)
Silverleaf whitefly (Bemisia argentifolia)
Sweet potato whitefly (Bemisia tabaci)

Pest description and crop damage Whitefly outbreaks are often associated with warm temperatures and susceptible plant material. The small football-shaped eggs are laid on the leaf underside with white wax deposits. Small, clear-to-beige, flat scales are evidence of immature whiteflies. The adult whitefly are tiny yellow-bodied insects with white wings that fly when disturbed.

Biology and life history The eggs are generally laid in clusters on the underside of leaves. The eggs hatch in about 9-12 days (70°F), and move to feeding sites, where they remain throughout the rest of the juvenile stages. The nymphs go through several instars or molts, than a final pupal stage from which the adult emerges. Egg to adult development takes about 32-39 days.

Scouting and thresholds Scout for whiteflies on incoming transplants. Look for the adults on leaf undersides and yellow sticky cards. The eggs can be seen near white wax deposits with a hand lens.

Management-biological control

Natural enemies include:

  • lady beetle (Delphastus pusillus)
  • parasitic wasp (Encarsia formosa; Eretmocerus mundis)- Encarsia has been very successful in some greenhouses.
  • pathogenic fungi (Beauveria bassiani; Paecilomyces fumosoroseus)

Management-chemical control

Direct control efforts at larvae feeding on leaf surfaces.

  • abamectin (Avid 0.15) at 0.009 lb ai/100 gal (8 fl oz). REI 12 hr. Suppression.
  • acephate (Precise, Orthene TR) at 0.024 lb ai/1,000 sq ft broadcast (0.6 oz). REI 24 hr.
  • acephate/fenpropathrin (Valent Tame/Orthene)
  • acetamiprid (Tristar 30SG) at 0.5 to 0.1 lb ai/100 gal (2.7 to 5.3 oz). REI 12 hr.
  • azadiractin (Azahar, Azatin XL)-Some formulations are OMRI-listed for organic use.
  • Beauvaria bassiana (Botanigard, Mycotrol, Naturalis L)-Some formulations are OMRI-listed for organic use.
  • bifenthrin (Talstar) at 0.168 to 0.335 lb ai/1,000 sq ft. REI 12 hr. Restricted use pesticide.
  • buprofezin (Talus 70DF) at 0.38 lb ai/a. REI 12 hr.
  • canola oil/pyrethrins (E.B. Stone, Earth-tone, Worryfree)-Some formulations are OMRI-listed for organic use.
  • chlorpyrifos (Quali-Pro Chlorpyrifos) at 0.25 to 0.5 lb ai/100 gal. REI 24 hr. Restricted use pesticide.
  • clarified hydrophobic extract of neem oil (Triact50)-Some formulations are OMRI-listed for organic use.
  • clothianidin (Arena 0.25G) at 0.45 to 0.63 oz ai /100 gal. REI 12 hr. Soil treatment refer label.
  • cyantraniliprole (Mainspring) at 0.013 to 0.1 lb ai/100 gal foliar or 0.16 lb ai/100 gal drench. REI 4 hr.
  • cyfluthrin (Decathlon) at 1.9 oz/100 gal. REI 12 hr.
  • cyfluthrin/imidacloprid (Discus N/G) at 0.063 lb ai/100 gal foliar; 0.009 to 0.014 lb ai/1,000 ft soil. REI 12 hr.
  • diflubenzuron (Adept) at 0.5 oz ai/100 gal.
  • dinotefuran (Safari 20SG) at 0.1 to 0.2 lb ai/1,000 ft sq; 0.05 to 0.1 lb ai/100 gal. REI 12 hr.
  • fenazaquin (Magus Miticide) at 0.15 to 0.3 lb ai/a. REI 12 hr.
  • fenproxymate (Akari 5SC) at at 0.079 lb ai/100 gal. REI 12 hr.
  • flonicamid (Aria) at 0.09 to 0.134 lb ai/100 gal. REI 12 hr.
  • flupyradifurone (Altus) at 10.5 to 14 fl oz/a. REI 4 hr.
  • garlic oil/powder (Allityn)-Some formulations are OMRI-listed for organic use.
  • imidacloprid (Marathon II) at 0.027 oz ai /100 gal foliar. REI 12 hr. Drench and irrigation permitted.
  • Isaria fumosoroseus (PFR 97) at 0.175 to 3.5 lb ai/100 gal foliar. REI 4 hr. Some formulations are OMRI-listed for organic use.
  • lambda-cyhalothrin (Scimitar GC) at 0.023 to 0.043 lb ai/100 gal. REI 24 hr.
  • Metarhizium anisopliae strain F52 (Met52 EC)
  • naled (Dibrom 8) as vapor treatment
  • novaluron (Pedestal) at 0.039 to 0.052 oz ai/100 gal. REI 12 hr.
  • oil of rosemary/peppermint (Ecotec for WA only)-Some formulations are OMRI-listed for organic use.
  • potassium laurate (several labels)-Some formulations are OMRI-listed for organic use.
  • pymetrozine (Endeavor) at 1.25 to 2.5 oz ai/100 gal. REI 12 hr.
  • pyrethrum/piperonyl butoxide
  • pyridaben (Sanmite) at 4 to 6 oz/100 gal. REI 12 hr.
  • pyrifluquinazon (Rycar) at 0.023 to 0.045 lb ai/100 gal. REI 12 hr. Limit 2 treatments per crop.
  • pyriproxyfen (Distance) at 0.041 to 0.054 lb ai/100 gal (6 to 8 fl oz) foliar. REI 12 hr.
  • s-kinoprene (Enstar AQ) at 0.012 to 0.024 lb ai/10,000 sq ft. REI 4 hr.
  • spiromesifen (Judo) at 1 to 4 fl oz/100 gal. REI 12 hr.
  • tau-fluvalinate (Mavrik Aquaflow) at 0.063 to 0.156 lb ai/100 gal. REI 12 hr.
  • thiamethoxam (Flagship 25WG) as fogger. REI 12 or 24 hr.
  • tolfenpyrad (Hachi-Hachi) at 0.14 to 0.33 lb ai /100 gal. REI 12 hr.