Comparative toxicity of an acetogenin-based extract and commercial pesticides against citrus red mite.
Acetogenins, a class of natural compounds produced by some Annonaceae species, are potent inhibitors of mitochondrial electron transport systems. Although the cellular respiration processes are an important biochemical site for the acaricidal action of compounds, few studies have been performed to assess the bioactivity of acetogenin-based biopesticides on spider mites, mainly against species that occur in orchards. Using residual contact bioassays, this study aimed to evaluate the bioactivity of an ethanolic extract from Annona mucosa seeds (ESAM) (Annonaceae) against the citrus red mite Panonychus citri (McGregor) (Acari: Tetranychidae), an important pest of the Brazilian citriculture. ESAM is a homemade biopesticide which was previously characterized by its high concentration of acetogenins. It caused both high mortality of P. citri females (LC50 = 7,295, 4,662, 3,463, and 2,608 mg l(-1), after 48, 72, 96, and 120 h of exposure, respectively) and significant oviposition deterrence (EC50 = 3.194,80 mg l(-1)). However, there was no effect on P. citri female fertility (hatching rate). In addition, the ESAM efficacy (in terms of its LC90) was compared with commercial acaricides/insecticides (at its recommended rate) of both natural [Anosom(®) 1 EC (annonin), Derisom(®) 2 EC (karanjin), and Azamax(®) 1.2 EC (azadirachtin + 3-tigloylazadirachtol)] and synthetic origin [Envidor(®) 24 SC (spirodiclofen)]. Based on all of the analyzed variables, the ESAM exhibited levels of activity superior to other botanical commercial acaricides and similar to spirodiclofen. Thus, our results indicate that ESAM may constitute a biorational acaricide for citrus red mite integrated pest management in Brazilian citrus orchards, particularly for local use.
Department of Entomology and Acarology, "Luiz de Queiroz" College of Agriculture, University of São Paulo (ESALQ/USP), Av. Pádua Dias, 11, Agronomia, Piracicaba, São Paulo, CEP 13418-900, Brazil, leandro_universidade@hotmail.com.
Leandro do Prado
Ldo P
Ribeiro
Odimar Zanuzo
OZ
Zanardi
José Djair
JD
Vendramim
Pedro Takao
PT
Yamamoto
D056810:Acaricides / Q000494:pharmacology*; D054378:Acetogenins / Q000494:pharmacology*; D000818:Animals; D005260:Female; D005298:Fertility / Q000187:drug effects; D010058:Oviposition / Q000187:drug effects; D010571:Pest Control / Q000379:methods*; D040102:Tetranychidae / Q000187:drug effects* / Q000502:physiology
D056810:Acaricides; D054378:Acetogenins