PMC

a)% of time (±s.e.m.) spent in the quadrant containing methyl salicylate (regardless of concentration), and in the quadrant containing uninfested cowpea; b) repellency of methyl salicylate (±s.e.m.) by flight form at 1 mg/ml; c) graph showing role of age, sex and morph in repellency of 1 mg/ml methyl salicylate (expressed as log-transformed ratio of time spent in methyl salicylate quadrant over time spent in any treatment quadrant), in which repellency is shown to increase with age in inactive males. Methyl salicylate was overall significantly repellent for females and inactive morph insects, but was not significantly repellent for males and active morph insects. 25% would indicate no preference for a quadrant in a) and b). Dots and stars indicate a difference between bars or groups with a significance threshold of: #  =  0.1, *  =  0.05, **  =  0.01.

Micrograph of methyl salicylate microcapsules.

Chemical structure of compound DL0309 (methyl salicylate 2-O-β-D-lactoside).

Infrared spectroscopy (FTIR) of methyl salicylate, gelatin and gum Arabic and the microcapsules obtained.