Susceptibility of the predatory stinkbug Picromerus bidens to selected insecticides

Abstract

The Palaearctic stinkbug Picromerus bidens L. (Heteroptera: Pentatomidae) has been considered as a potential biocontrol agent of several defoliator pests in various agricultural and forest ecosystems. It may therefore be a valuable alternative for the Nearctic pentatomid Podisus maculiventris (Say) (Heteroptera: Pentatomidae), the augmentative use of which has largely been abandoned in Europe given its possible environmental impact as an exotic polyphagous predator. However, no study has yet documented the impact of insecticides on P. bidens, which is essential to evaluate the possible combination of this predatory pentatomid with current insecticide applications in integrated pest management (IPM) programmes. This study reports on laboratory experiments investigating the susceptibility of P. bidens to five insecticides with different modes of action: the pyrethroid deltamethrin, the diacylhydrazine methoxyfenozide, the juvenile hormone mimic pyriproxyfen, the spinosyn spinosad, and the neonicotinoid imidacloprid, all of which are used to control defoliator pests. Fourth-instar nymphs and female adults of the predator were exposed to formulated materials of the insecticides by residual contact. Methoxyfenozide and spinosad did not cause significant mortality to 4th instars and female adults of P. bidens. In contrast, deltamethrin and imidacloprid were harmful to nymphs and adults of the predator, with LC 50 values ranging between 1.5 and 9.9 mg a.i./l. Pyriproxyfen was toxic to 4th instars with an LC 50 value of 13.9 mg a.i./l but did not affect female adults. Reproduction and longevity of P. bidens were not adversely affected when the predator was exposed to field concentrations of spinosad, methoxyfenozide, or pyriproxyfen, or sublethal concentrations (around LC 10 ) of deltamethrin and imidacloprid. The results from residual contact experiments suggest that methoxyfenozide, spinosad, and to a lesser extent, pyriproxyfen may be compatible with P. bidens in an IPM programme. Further experiments assessing food chain toxicity of these compounds should offer a more complete picture of their selectivity.

Effect of Surround WP on Behavior and Mortality of Apple Maggot (Diptera: Tephritidae)

“…Kamminga et al (2009) reported that spinosad was as effective as lambda-cyhalothrin in laboratory bioassays against C. hilaris and E. servus. Spinosad was also promising against H. halys in our studies, and this material has demonstrated selectivity against the predatory stink bug, Picromerus bidens (L.) (Mahdian et al 2007).…”

“…Organic insecticides may also continue being used in conjunction with other management tactics. To date, very little is known regarding the efficacy of insecticidal materials approved for use in organic farming against H. halys and fewer organic insecticides are available compared with conventional insecticides that have proven effective against other pentatomids (Durmusoglu et al 2003;Trdan et al 2006;Mahdian et al 2007;Kamminga et al 2009). …”

The negative effect of some selective insecticides on the functional response of a potential biological control agent, the spider Philodromus cespitum

“…In our study, it caused almost 10% mortality. Its residues were not toxic to Orius bugs (Studebaker and Kring 2003) or Picromerus bugs (Mahdian et al 2007), but reduced the fecundity and slowed the development of Deraeocoris bugs (Kim et al 2006).…”

“…It was found to be toxic to heteropterans (Studebaker and Kring 2003;Myers et al 2006), some hymenopteran parasitoids (Nowak et al 2001), staphylinid beetles, and earwigs (Cisneros et al 2002). It has, however, little negative effect on the survival or reproduction of predatory mites, Harmonia coccinellids (Musser and Shelton 2003), Deraeocoris bugs (Kim et al 2006), Picromerus bugs (Mahdian et al 2007), and braconid wasps (Vargas et al 2001).…”

Spinosad Affects Chemical Communication in the German Cockroach, Blatella germanica (L).

“…When ingested or topically applied to an insect, spinosad acts on the nicotinic acetylcholine and GABA receptors (Watson 2001). While spinosad is active against a wide range of insect pests (Thompson et al 1997), it appears to be harmless to mammals and predatory insects (Madhian et al 2007). …”