Acaricidal activity of essential oils from five endemic conifers of New Caledonia on the cattle tick Rhipicephalus (Boophilus) microplus

Abstract

The aim of the present study was to demonstrate acaricidal activity on the cattle tick Rhipicephalus (Boophilus) microplus of essential oils from endemic conifers of New Caledonia in the context of the development of natural alternatives. Acaricidal activity of essential oils extracted from resin and heartwood of five endemic conifers of New Caledonia (Araucaria columnaris, Agathis moorei, Agathis ovata, Callitris sulcata, and Neocallitropsis pancheri) was evaluated on 14- to 21-day-old Rhipicephalus microplus tick larvae using the Larval Packal Test bioassay. A first screening with 5% dilute solution was carried out and the oils with 100% of mortality at this rate were diluted until no activity was shown. The heartwood oils of the two Cupressaceae were the most active with LC50 value of 0.65% for C. sulcata and 0.55% for N. pancheri while resin oil of A. columnaris (LC50=1.62%) was the most active of the Araucariaceae family. Negative control (ethanol) was not toxic to the larvae. The chemical composition of essential oil from resin of A. columnaris was analyzed by gas chromatography-mass spectrometry. The essential oil was characterized by high level of sesquiterpene hydrocarbons and oxygenated sesquiterpenes and was composed mainly of aromadendrene (23.1%) and bicyclogermacrene (16.0%). In order to compare different plant resources in a sustainable program of natural acaricide, an "essential oil efficiency EOE" can be measured as the ratio between the yield of extraction and LC50 value. This study shows that A. columnaris (EOE=2.36) and N. pancheri (EOE=3.51) could provide valuable and effective natural acaricides for control of the cattle tick R. microplus.

Interaction of plant essential oil terpenoids with the southern cattle tick tyramine receptor: A potential biopesticide target

“…These alternatives may include new chemistry and/or the identification of novel or underutilized biochemical targets. Several essential oils have been shown to be toxic to the cattle fever tick (R. annulatus) and to the southern cattle tick (R. microplus) [8,22,26,36,37,39,40,46]. Here, we report on the development of an expression system for the southern cattle tick's tyramine receptor (RmTAR1), and present evidence that this receptor may be a potential target of biopesticides.…”

“…Recently, there has been a growing interest in the use of botanical acaricides, particularly essential oils, to control R. microplus and R. annulatus [8,22,26,36,37,39,40,46]. For instance, the essential oil from cumin seeds (Cuminum cyuminum) and allspice berries (Pimenta dioica) resulted in 100% mortality at concentrations between 2.5% and 20% (v/v).…”

First Report on Chemical Composition and Acaricidal Activity on the Cattle Tick <i>Rhipicephalus microplus</i> of Essential Oil from <i>Monanthotaxis parvifolia</i> (Oliv.) Verdc

“…[9,19,20]. The non-strong acaricidal activity observed may due to the low proportion of compounds with acaricidal potential.…”

“…Plant extracts with acaricidal activity provide a potential alternative as a substitute for synthetic acaricides currently used for tick control, since promising results have been obtained through testing some plant extracts against R. microplus [5,6,7,8,9].…”

Effect of Organic Fertilizer Doses on the Plant Growth, Essential Oil Production and Chemical Substances of “Carqueja” over Two Harvest Moments

“…Lago et al [40] studied the composition of six species of Baccharis (Southeast of Brazil) and also detected bicyclogermacrene in the essential oil samples. Lebouvier et al [41] identified that the essential oil from five species of conifer primarily consisted of bicyclogermacrene, and this essential oil was effective as a natural acaricide.…”