Microencapsulated essential oils active agaist indianmeal moth

The toxic effects of Rosmarinus officinalis and Thymus vulgaris microencapsulated essential oils were assayed against Plodia interpunctella larvae. The activity of the oil was observed after diet contamination with the microencapsules and vapour exposition. the effect of the oils is maily produced by the contamination of the diet with the active principles released from the microcapsules and is a consequence of ingestion. Thymus and rosmarinus oils wer extremely effective against I-II instr larvae, that at low concentration (0,1%) gave martalities over 50%. By increasing the microcapsules concentration in the diet, proportional increase in mortality were recorde, which reached values up to 80% in both treatments. The difference found in the release pattern of the oils could be due to the different hydrophilic characteristics. thymus microcapsules sitll contain about 75% of the oli after 25 dys while Rosmarinus formulation only 25%