The potential abilities of 3-methylbenzaldehyde derived from Myosotis arvensis oil and its structural analogues to actas new acaricide and mite kit (mite color deformation) against Tyrophagus putrescentiae (Schrank) were evaluated in thepresent study. Based on the LD50 values, 2,4,5-trimethylbenzaldehyde (0.78 μg/cm3) had highest vapor action against T.putrescentiae, followed by 2,4-methylbenzaldehyde (1.14 μg/cm3), 2,5-dimethylbenzaldehyde (1.29 μg/cm3), 2-methylbenzaldehyde (1.32 μg/cm3), 2,3-dimethylbenzaldehyde (1.55 μg/ cm3), 3-methylbenzaldehyde (1.97 μg/cm3), and4-methylbenzaldehyde (2.34 μg/cm3). The color deformation of seven methylbenzaldehyde analogues mixed with2,3-dihydroxybenzaldehyde against T. putrescentiae showed mite color deformation, from coloress to reddish brown, andvaluable to distinguish with the naked eye. In addition, there was no antagonistic interactions between 2,3-dihydroxybenzaldehydeand the methylbenzaldehyde analogues. These finding suggests that the methylbenzaldehyde analogues could be developedas dual functional agent to protect from fall in the commercial value of stored food products.

The repellent constituents of essential oils from Zanthoxylum armatum (Rutaceae) seed and Zanthoxylum piperitum fruit against female Stomoxys calcitrans were analyzed by gas chromatography and gas chromatography-mass spectrometry. The repellency of two Zanthoxylum essential oils and 11 oil compounds against female S. calcitrans was examined using a skin bioassay. Results were compared with those of the most widely used repellent DEET. Both Z. armatum seed and Z. piperitum fruit oils provided complete and good protection from fly bites for 30 min at 0.4 and 0.2 mg/cm2, respectively. At 0.05 mg/cm2, both oils gave ca 70 and 40% repellency at 30 and 60 min post-treatment, respectively, whereas DEET provided 83 and 73% protection. Of test compounds, cuminaldehyde at 0.05 mg/cm2 gave 92 and 69% repellency at 10 and 30 min post-treatment, respectively, whereas 1,8-cineole, and citronellal provided approx. 76% repellency at 10 min. The Zanthoxylum oils and their constituents, particularly cuminaldehyde, merit further study as potential insect repellents for the protection from humans and domestic animals from biting and nuisance caused by S. calcitrans.