02741naa a2200373 a 450000100080000000500110000800800410001902400520006010000220011224501230013426000090025752016660026665000150193265000200194765000190196765000210198665000280200765000100203565000140204565000110205965000140207070000210208470000170210570000200212270000160214270000250215870000160218370000240219970000230222370000190224670000200226570000170228577300650230221490402022-12-01       2022    bl uuuu     u00u1 u    #d7 ahttps://doi.org/10.1007/s10493-022-00743-62DOI1 aGONZAGA, B. C. F.  aCombination of synthetic acaricides with (E)-cinnamaldehyde to control Rhipicephalus microplus.h[electronic resource]  c2022  aThis work had the objectives to (1) evaluate the susceptibility of various Rhipicephalus microplus populations to commercial acaricides, and (2) select commercial acaricides (50-80% effective) and evaluate the effects of binary combinations of the phenylpropanoid (E)-cinnamaldehyde with selected commercial acaricides to control R. microplus under laboratory and field conditions. Using adult immersion tests with 116 populations and 14 commercial acaricides, products showing 50-80% effectiveness (percent control) with the lowest number of active ingredients were selected. Acaricides containing amitraz or chlorfenvinphos were tested in combination with (E)-cinnamaldehyde on a field population (strain CM). We found that (E)-cinnamaldehyde enhanced the activity of both commercial acaricides against R. microplus larvae; however, the enhancement was more accentuated when using amitraz. Experiments combining (E)-cinnamaldehyde + amitraz on unfed larvae and engorged females from another population (strain Gyn) were performed, verifying (E)-cinnamaldehyde enhanced the activity of amitraz. In the field experiment, the application of (E)-cinnamaldehyde appeared toxic to the tick hosts (cattle). We concluded that (E)-cinnamaldehyde enhanced the activity of amitraz against unfed larvae and engorged females of R. microplus; however, in the field test this phenylpropanoid caused intoxication in the cattle. Studies searching for new combinations of compounds from essential oils with amitraz deserve attention, as well as studies to develop formulations using amitraz + (E)-cinnamaldehyde that will be efficient and will not have toxic effects in cattle.  aAcaricides  aChlorfenvinphos  aEssential oils  aPhenylpropanoids  aRhipicephalus microplus  aTicks  aAcaricida  aBovino  aCarrapato1 aMORAES, N. R. de1 aGOMES, G. W.1 aCOUTINHO, A. L.1 aVALE, F. L.1 aSOUSA, L. J. M. P. e1 aMARRETO, L.1 aRODRIGUES, D. de C.1 aPRATA, M. C. de A.1 aMARCHESINI, P.1 aLOPES, W. D. Z.1 aMONTEIRO, C.  tExperimental and Applied Acarologygv. 88, p. 191-207, 2022.