sodininkystė ir daržininkystė 25(4)

SCIENTIFIC WORKS OF THE LITHUANIAN INSTITUTE OF
HORTICULTURE AND LITHUANIAN UNIVERSITY OF AGRICULTURE.
SODININKYSTË IR DARÞININKYSTË. 2006. 25(4).
THE EFFECT OF ABAMECTIN ON STRAWBERRY
MITE TARSONEMUS PALLIDUS
(ACARI: TARSONEMIDAE) IN STRAWBERRIES
Laimutis RAUDONIS
Lithuanian Institute of Horticulture, Laboratory of Plant Protection.
LT-54333 Babtai, Kaunas distr., Lithuania.
E-mail l.raudonis@lsdi.lt
The effect on the seasonal abundance of strawberry mite (Tarsonemus pallidus
Banks.) and toxicity of Abamectin 18 g l -1 was studied in strawberries under field
conditions in 2005–2006. Abamectin 18 g l -1 , 21.6 g AI ha -1 was from moderately to
very toxic 3 and 7 days after treatment and slightly toxic 21 days after treatment.
The mortality of strawberry mite ranged from 58.9 to 77.8 proc. 3 and 7 days and
41.9–48.4 proc. 21 days after treatment, respectively. Abamectin 18 g l -1 , 18.0 g
AI ha -1 was only moderately toxic (mortality – 50.5–56.9 proc.) 3 and 7 and slightly
toxic (mortality – 40.9 and 41.6 proc.) 21 days after treatment. The field rate (9.0 g
AI ha -1 ) of Abamectin 18 g l -1 was slightly toxic (mortality – 43.7–45.6 proc.) 3 and
7 and from non to slightly toxic (mortality – 16.3–30.6%) 21 days after treatment.
The toxicity of Lambdacihalotrin 50 g l -1 , 25.0 g AI ha -1 was similar to Abamectin
18 g l -1 , 9.0 g AI ha -1 , meanwhile the toxicity of Spirodiclofen 240 g l -1 , 96.0 g AI ha -1
was similar to the toxicity of Abamectin 18 g l -1 , 21.6 g AI ha -1 to strawberry mite.
Key words: Abamectin, rates, strawberry, Tarsonemus pallidus, toxicity.
Introduction. Outbreaks of phytophagous mites have been induced mostly
due to applications of broad-spectrum pesticides that kill predators, which would
control these mites. The widely used synthetic pyrethroids are very effective against
pest insects, but it has not any effect on mites and it causes increasing phytophagous
mite populations that induce severe damage of plants (Edland, 1994; Raudonis
2004). On the other hand, frequent acaricide applications against the increased phytophagous
mite population result in greater resistance (Elzen, Hardee, 2003; Van
Leeuwen et al., 2005). Integrated pest management (IPM), which is based on selective
toxicity to the phytophagous mites and harmless to predatory mite, became the
most relevant strategy of plant protection (Edland, 1994; Leake, 2000; Linquist,
2000; Klassen, 2000).
Strawberry mite is one of the key pests of horticultural plants, causing serious
indirect damage to the crop in Lithuania (Raudonis, 2002, 2005). There have not
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