Effects of Insecticides on Immature and Adult Western Flower Thrips (Thysanoptera: Thripidae) in Israel

Management strategies for western flower thrips in vegetable greenhouses in Iran: a review

“…In another study to determine the most effective insecticides for the control of WFT, insecticides toxicity was tested in the LC99.99 and results showed that fipronil, with two formulations of WG and SC, came out as one of the most effective (Herron et al 1996). Kontsedalov et al (1998) evaluated the effect of abamectin, carbosulfan, methiocarb, monocrotophos, methamidophos, cypermethrin, and acrinathrin on fertility, mortality, and feeding behaviour of the adult F. occidentalis and the effect of abamectin, carbosulfan, methiocarb, and acrinathrin on immature stages in Israel. According to the results, cypermethrin at 2000 ppm had no direct effect on adult and carbosulfan had a greater impact on the feeding behaviour and fertility.…”

“…In a field experiment with the use of α-cypermethrin with and without rotation, more than a 114-fold resistance to α-cypermethrin (LC 50 ) was found (Herron & Cook 2002). Nonetheless, cypermethrin resistance in pepper greenhouses in Israel evolved while no new individuals had entered the population for 7 years and the population had not been under any selection pressure (Kontsedalov et al 1998). This may occur as a result of the host plant secondary metabolites.…”

Management Strategies for Western Flower Thrips and the Role of Insecticides

“…There are cases of long term maintenance of resistance in the absence of insecticide exposure. Kontsedalov et al (1998) reported that resistance to the pyrethroid cypermethrin did not decline after more than seven years of non-exposure for a laboratory colony. Likewise, resistance to organophosphates can be maintained in field and laboratory populations for several years without exposure (Brødsgaard, 1994;Robb, 1989).…”

“…In northern areas of Europe, western flower thrips is largely restricted to glasshouses 2 because climatic conditions prevent persistent populations from establishing (McDonald et al, 1997). In more southerly areas around the Mediterranean basin, populations have become established in open field crops, which facilitates the repeated colonization of protected crops (Brødsgaard, 1993;Kontsedalov et al, 1998). Since the distribution review by Kirk and Terry (2003), western flower thrips has continued to spread to new regions.…”

“…The potential for continual recolonization of crops limits the observed field efficacy of insecticides (Eger et al, 1998;Reitz et al, 2003). This ongoing dispersal means that even repeated insecticide applications have little utility in reducing pest damage, especially in high value crops with low damage thresholds (Bauske, 1998;Kontsedalov et al, 1998). Once having landed on plants, western flower thrips preferentially reside within flowers or other concealed, protected places on plants (Hansen et al, 2003;Kirk, 1997a).…”