The tolerance of the lucerne flea, Sminthurus viridis (Collembola: Sminthuridae), to currently registered pesticides in Australia

Abstract

Abstract Sminthurus viridis (lucerne flea) is a major crop and pasture pest throughout southern regions of Australia that experience a Mediterranean type climate. It is particularly problematic at the establishment phase, and chemicals are currently the main option available to farmers for their control. Few studies have assessed the currently registered pesticides for the control of S. viridis, and rates of application are generally similar to the frequently co‐occurring red‐legged earth mite, Halotydeus destructor, despite few comparisons between species for their susceptibility being made. Here, we examine the response of S. viridis to six pesticides (α‐cypermethrin, bifenthrin, omethoate, methidathion, chlorpyrifos and phosmet) and then directly compare them with H. destructor. S. viridis displayed similar dose–response curves for bifenthrin, omethoate, chlorpyrifos and phosmet. It had greater sensitivity to methidathion and greater tolerance to α‐cypermethrin. S. viridis was found to be significantly more tolerant than H. destructor to all pesticides tested, with the exception of chlorpyrifos. This indicates that rates of application for control of S. viridis should be greater than H. destructor and that the organophosphates are likely to provide the most effective control of this pest.