Comparative toxicity of spirodiclofen and lambdacihalotrin to Tetranychus urticae, Tarsonemus pallidus and predatory mite Amblyseius andersoni in a strawberry site under field conditions
Laboratory of Plant Protection, Lithuanian Institute of Horticulture,LT-54333 Babtai, Kaunas distr., Lithuania;e-mail: l.raudonis@lsdi.lt
Abstract:
The relative toxicity of broad-spectrum acaricide spirodiclofen 240 g AI l-1 from a new class of active ingredients and synthetic pyrethroid insecticide–acaricide lambdacihalotrin 50 g AI l-1 to the seasonal abundance of Tetranychus urticae Koch (Acari: Tetranychidae), Tarsonemus pallidus Banks (Acari: Tarsonemidae) and predatory mite Amblyseius andersoni Chant (Acari: Phytoseiidae) was evaluated in strawberry sites under field conditions in 2003–2004. The field rate (96 g AI ha-1) of spirodiclofen was very toxic (82.3–96.1% mortality) after 7 and 21 days after treatment to T. urticae. The mortality to T. pallidus ranged from 76.6- 79.3% after 7 days, and from 59.0–74.9% after 21 days following treatment respectively. The rate (48 g AI ha-1) of spirodiclofen was very toxic (78.8–87.8% mortality) after 7 days and moderately toxic (54.1–73.4% mortality) after 21 days following treatment to T. urticae. The lower rate of spirodiclofen was moderately toxic after 7 days and from non- to slightly toxic after 21 days following treatment to T. pallidus. The toxicity of lambdacihalotrin (25 g AI ha-1) to T. urticae was similar to a lower rate of Spirodiclofen. Lambdacihalotrin was non-toxic to T. pallidus, but moderately toxic (51.4–62.5% mortality) after 7 and 21 days following treatment to A. andersoni. Both rates of spirodiclofen were non-toxic to predatory mites.
Key words:
Amblyseius andersoni, lambdacihalotrin, spirodiclofen, strawberry