Christine Casey Michael Parrella Department of Entomology UC Davis

IR-4 Ornamental Horticulture Program 2011 October 5 – Sacramento, CA

Effect of Pesticides Used for

Western Flower Thrips Control on Thrips Natural Enemies

Acknowledgements

Technical assistance Andrew Melicharek and Machiko Murdock

Funding USDA-IR4, protocol #11-017

Products evaluated Pesticides • Hachi-Hachi (tolfenpyrad EC, 21A) • Kontos (spirotetramat, 23) • Pylon (chlorfenapyr, 12B) • Overture (pyridalyl, unknown) • NNI-0101(pyrifluquinazon, unknown) • Tolfenpyrad SC (21A)

Hypoaspis miles

• Will consume most soil-dwelling arthropods

• Comes in 1 liter bottle that contains 10,000 mites

• Provides slow, consistent control

Photo K. Hall

Amblyseius swirskii

• Will consume thrips larvae and whitefly eggs and larvae

• Comes in 500 ml bottle that contains 5000 mites

Photo Sesil IPM

Methods • Swirskii:

– ½ tsp. vermiculite carrier applied to petri dish – Pesticide applied with airbrush

• Hypoaspis – ½ tsp. peat carrier applied to petri dish – Pesticide applied with airbrush (Trial 1) and

hand sprayer (Trial 2)

Both counted at 24 and 48 HAT

• Half teaspoon weighs approximately 0.75g

• Contains 5 to 10 adult A. swirskii and over 100 bran mites

Results -- Swirskii

Treatment Adult % mortality 24 HAT ± SE

Adult % mortality 48 HAT ± SE

Hachi-Hachi 0 0 Kontos 0 0 NNI 0 1 ± 1 Overture 0 0.71 ± 0.71 Pylon 2.06 ± 1.38 0 Tolfenpyrad 0.63 ± 0.63 1.11 ± 1.11 Untreated control 1.88 ± 1.33 0 Water treated control 3.17 ± 1.8 0

Mea

n %

mor

talit

y ±

SE

Results -- Hypoaspis

Mea

n %

mor

talit

y ±

SE

Results -- Hypoaspis

Summary

• Swirskii – Better method needed; residue test?

• Hypoaspis – Kontos was the safest in both trials – Hachi-Hachi and NNI were variable – Overture, Pylon and Tolfenpyrad were

consistently toxic between the two trials

Thank you

Questions?