Piperonyl butoxide resistance mechanisms

Resistance to pyriproxyfen was observed only in whitefly, and has been reported in Israel [40] and the United States [41]. The resistance to pyriproxyfen in Israel is reviewed briefly as an example. Pyriproxyfen was introduced in Israel in 1991. Although it was sprayed once a season to control whitefly (B. tahaci), the whitefly developed a middle to high resistance up to 1996. The use of pyriproxyfen was stopped in 1996 and 1997. The resistance mechanism is unknown it is reported that piperonyl butoxide, an oxidase inhibitor, does not have a synergistic effect [42]. The resistance is incompletely or partially dominant [43], and the susceptibility of whitefly was recovered by stopping the use of pyriproxyfen [44, 45]. 

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