The predatory mite Thyphlodromus piry was chosen as non-target arthropod (NTA) standard specie since it proved to be the most sensitive in a range of experiments carried out on different species of NTA with many different Plant Protection Products.
Protonymphs 24 hours old, are exposed to the test substance applied on glass plate (laboratory test) or on natural surface as plants or parts of plants (extended laboratory test) in order to evaluate the effects in terms of mortality over 7 days exposure period and sub-lethal effects in terms of viability of surviving females over the following 7 days.

TEST SYSTEM
Thyphlodromus piry protonymphs 24 hours old.

STUDY DESIGN
Range finding is carried out with at least 3 application rates of the test substance and 1 untreated control (3 replicates/treatment or control)  with 20 mites/replicate.
Limit test includes 1 application rate of the test substance, 1 untreated control and 1 toxic reference treatment (5 replicates/treatment or control) with 20 mites/replicate.
Rate-response test includes at least 5 application rates of the test substance, 1 untreated control and 1 toxic reference treatment (3 replicates/treatment or control) with 20 mites/replicate.

In order to evaluate the duration of the effects of the test substance and the recovery capacity of the insects it is possible to carry out an extended laboratory test with aged residues of the test substance.
The plants are treated in semi-field conditions and the leaves of the treated plants, after an adequate aging time, are moved to laboratory to perform the standard test as previously described.

ENDPOINTS
Mortality: NOER/LR₅₀ at 7 days after treatment.
Reproduction capacity: NOER/ER₅₀ from 7 days to 14 days after treatment.
Study includes GLP management and reporting.

REFERENCES AND GUIDELINES
IOBC/WPRS Guidelines (Mead-Briggs et al., 2000).
ESCORT I Guidance Document (Barret K.L. et al., eds. 1994).
ESCORT II Guidance Document (Candolfi et al., eds. 2001).
ESCORT 3 (Setac publication, 2010).