الفهرس 
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Abstract
The aim of this work was to determine the efficacy and residues of spinosad, lufenuron and hexythiazox for controlling strawberry pests. To achieve this aim, laboratory and field bioassay experiments were carried out and residues of the tested insecticides were determined in fruit and leaves of strawberry. Laboratory experiments showed that the spinosad was the most effective insecticide after 24 h of exposure and was similar in efficacy with lufenuron after 48 or 72 h of exposure. While, hexythiazox was the least effective on S. littoralis larvae tested. Time-mortality relationship experiments showed that spinosad was faster than lufenuron or hexythiazox in killing either 50 or 90% of the treated larvae when tested at 10 or 100 ppm. The efficacy of spinosad and lufenuron against thrips and aphid when tested under field conditions showed mean effect ranged from 73.8 to 82 %. Residues and loss rates of hexythiazox and spinosad in and on strawberry fruit and leaves showed that the initial deposits detected in strawberry fruit and leaves were 2.321 and 4.621 mg kg-1 (hexythiazox) and 0.972 and 4.406 mg kg-1 (spinosad), respectively. The initial concentrations were gradually dropped in fruit and leaves to 0.019 and 0.169 mg kg-1 (hexythiazox with 99.18 and 96.34% loss rate) and 0.007 and 0.103 mg kg-1 (spinosad with 99.28 and 97.66% loss rate), respectively, after 15 days of spraying. The amounts of hexythiazox and spinosad residues in strawberry fruit after 6 days of spraying were lower than the residue tolerance in strawberry fruit (0.3 mg kg-1) reported by EU Pesticides Database (European Commission). Results of processing showed good effect of washing and preparing strawberry into jam which indicating 91.81 and 100% reduction in residues of hexythiazox and spinosad, respectively due to processing with a hazard index <1 after 6 days of spray. Depending on the findings, the treated strawberry fruit from the 6th day after spraying to the end of the experiment is considered acceptable for human consumption.