Experimental and Applied Acarology (2002) 26, 243-251

Fernando Joly Campos and Celso Omoto (2002)
Resistance to hexythiazox in Brevipalpus phoenicis (Acari: Tenuipalpidae) from Brazilian citrus
Experimental and Applied Acarology 26 (3-4), 243-251
Abstract: The objective of this study was to collect baseline information for implementing an acaricide resistance management program of Brevipalpus phoenicis (Geijskes) to hexythiazox in Brazilian citrus groves. The egg susceptibility of B. phoenicis to hexythiazox was measured by a direct contact bioassay. The estimated LC₅₀ for the S strain was 0.89 mg hexythiazox L^-1 of water (95% FL 0.75-1.03). After hexythiazox selection of a field-collected population associated with intense hexythiazox use, a resistance ratio greater than 10,000-fold was detected. Results from a survey revealed a great variability in the frequency of resistance in populations of B. phoenicis collected from citrus groves located in the State of São Paulo. No relationship was observed between the intensity of hexythiazox use and the frequency of resistance. Studies on dynamics of resistance showed that the resistance of B. phoenicis to hexythiazox is stable under laboratory conditions. Therefore, there is an urgent need to implement resistance management of B. phoenicis to hexythiazox in order to prolong its effective use in Brazilian citrus groves.
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Link to article at publishers website
Database assignments for author(s): Celso Omoto

Research topic(s) for pests/diseases/weeds:
pesticide resistance of pest

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Brevipalpus phoenicis	Citrus (genus)	Brazil (south)