Control of blueberry thrips, Frankliniella vaccinii Morgan, with permethrin and effect on yield and residue in fruit.

Permethrin at 0.4 kg a.i./ha controlled blueberry thrips Frankliniella vaccinii Morgan. There was no plant damage and crop yield was notably increased. Permethrin was extracted from berries with acetone, partitioned in hexane, cleaned-up on Florisil column and analysed by the electron capture gas chromatography using a 3% OV-210 column. No permethrin residues were found in the berries. The relative retention times of cis-, and trans-permethrins to aldrin were 10.3 and 12.1, respectively. The absence of permethrin from berries was further confirmed by TLC.