Entomopathogenic nematodes associated with essential oil of Lippia sidoides for control of Rhipicephalus microplus (Acari: Ixodidae)

Abstract

In vitro effect of the association of the entomopathogenic nematodes Heterorhabditis bacteriophora HP88 and Heterorhabditis indica LPP1 with the essential oil of Lippia sidoides on engorged females of Rhipicephalus microplus was assessed. Engorged females with homogeneous weights (p >0.05) were divided into six groups of ten ticks each (each female = an experimental unit). In the treated groups, the ticks were exposed to the oil (40 μl/ml=4%) and nematodes (300 entomopathogenic nematodes (EPNs/tick) separately and also to the nematodes together with the oil, while in the control group, the females were immersed in Tween 80 (3%). All the treatments caused a significant reduction in the egg mass weight (p <0.05). The hatching percentage of larvae was reduced (p <0.05) in the groups treated with H. bacteriophora HP88, H. indica LPP1, and H. bacteriophora HP88 associated with the oil, but in the group treated only with the oil, the hatching of percentage of larvae rate was similar to that of the control group (p >0.05). The percentage of control in the group exposed only to the oil was 50.7%, while in the other treated groups, the percentage of control was greater than 95 %, reaching 100 %in the group treated with H. indica LPP1 associated with the oil. The results of the L. sidoides essential oil in the concentrations tested in association with both H. bacteriophora HP88 and H. indica LPP1 indicate that these combinations can be used to control R. microplus.

General Characteristics, Phytochemistry and Pharmacognosy of Lippia sidoides

“…Pure essential oil in association with pathogenic nematodes Heterorhabditis bacteriophora and Heterorhabditis indica showed an insecticidal effect when applied on engorged females of R. microplus. All treatments reduced egg mass weight, but larval hatching percentage only reduced in treatments with the association of essential oil and nematodes, showing a control ranging between 99.7 and 100% [49].…”

Daños de Strategus aloeus (Coleoptera: Scarabaeidae) en dos especies de agave y su manejo a base de hongos entomopatógenos en suspensiones de aceite

“…Acuña et al (2015) trabajaron con el hongo M. robertsii para el control del gusano de la fruta Chloridea virescens (Fabricius) (Lepidoptera: Noctuidae) reportando un 100 % de mortalidad, Ahedo-Quero (2019) trabajó con el picudo del agave (S. acupunctatus) a base de formulaciones de aceites, y encontró que a las 72 horas hubo una efectividad del 100 % con el hongo B. bassiana + aceite de P. americana al 40 %. Es necesario evaluar la compatibilidad de aceites y agentes de control biológico (hongos y nematodos entomopatógenos) para saber si existen efectos sinérgicos, como mejorar la patogenicidad, evitar la desecación o mejorar la supervivencia (Monteiro et al, 2014;Shapiro et al, 1985).…”

Assessment of Entomopathogenic Nematodes in Oil Emulsions to Control Scyphophorus acupunctatus in Agave under Laboratory Conditions

“…The entomopathogenic nematodes S. feltiae and S. carpocapsae at a concentration of 9000 JIs applied in water presented 60% mortality 44 days after inoculation in S. acupuncatatus adults [22]. With Lippia sidoides oil associated with entomopathogenic nematodes, 100% mortality was observed in the control of Rhipicephalus microplus (Acari: Ixodae) [19,24]. It is important to continue searching for chemical materials and their combinations either as coadjuvants or additives to increase the mortality of biological controllers [25].…”