Ethanolic Plant Extracts as Potential Biomiticides Against Oligonychus perseae (Acari: Tetranychidae) on Avocado in Mexico

Abstract. Oligonychus perseae Tuttle, Baker & Abbatiello (Acari: Tetranychidae) is an economically important pest of avocado (Persea americana Mill.) in Mexico. Resistance reduced the efficacy of broad-spectrum miticides used to control this pest. Identification of reliable and more environmentally friendly alternatives is crucial for reduction of pesticide use in agriculture. This study determined the efficacy of three plant extracts derived from wild species, Petiveria alliacea L. (Phytolaccaceae), reseda luteola L. (Resedaceae), and Isocoma hartwegii (A. Gray) Greene (Asteraceae) for control of the mite. In vitro and field experiments were done. Ethanolic wild plant extracts from Petiveria alliacea and Isocoma hartwegii killed most mites by 24 hours after application in in-vitro assays. At field conditions, most effective extracts were from Petiveria alliacea and reseda luteola. Two commercial products derived from Azadirachta indica extract and combination of pepper + garlic extracts had good efficacy at in vitro and field conditions.