Side effects of diflubenzuron on a pear psylla predator:Forficula auricularia

Abstract

A series of laboratory, semi-field and field tests showed the high toxicity of diflubenzuron to Forficula auricularia L. nymphs, at concentrations of 15 and 20 g a.i./hl registered in various European countries and the United States to control Cydia pomonella L. Diflubenzuron proved more selective using the 10g/hi concentration registered in France, but several sublethal effects have been observed: morphological abnormalities, reduced weight increase and mobility. Unexpectedly for a chitin-deposit inhibitor, intake was reduced, which became apparent from the beginning of exposure to the insecticide, before the onset of the moulting process. In the semi-field tests, and despite diflubenzuron's slowing down effect on psylla nymphs, the earwig's reduced predatory activity due to the product resulted in greater growth of the psylla populations than without treatment. The field-test confirmed the efficacy of F. auricularia as a psylla predator, and the relative selectivity of diflubenzuron at the lowest concentration.

Biological control of woolly apple aphid,Eriosoma lanigerum(Hausmann), during transition to integrated fruit production for pipfruit in Central Otago, New Zealand

“…However, the lack of effect of lufenuron on the predators of WAA is less certain. These results with lufenuron contrast strongly with the known toxicity of diflubenzuron (another chitin synthesis inhibitor) to M. tasmaniae in the field and laboratory (Rumpf et al 1997), and to F. auricularia (Ravensberg 1981;Sauphanor et al 1993). In addition, Shaw et al (1997) reported reduced numbers of M. tasmaniae in the field following the use of oil plus buprofezin (another chitin synthesis inhibitor) when compared with oil alone; and Bueno and Freitas (2004) recorded moulting inhibition in the larvae of another lacewing Chrysoperla externa (Hagen) following treatment of eggs or larvae with lufenuron in the laboratory.…”

Non-target consequences of insecticides used in apple and pear orchards on Forficula auricularia L. (Dermaptera: Forficulidae)

“…Products shown to be safe for earwigs by other workers include B. thuringiensis (Sauphanor et al, 1993), etoxazole (Beliën, 2013), pirimicarb (Ffrench-Constant and Vickerman, 1985;Peusens and Gobin, 2008) and spirotetramat (Shaw and Wallis, 2010, Table 5). …”

“…They have been demonstrated to be important predators of many pests orchard including scale insects (McLeod and Chant, 1952;Karsemeijer, 1973), psyllids (Lenfant et al, 1994;Solomon et al, 1999), woolly apple aphid, Eriosoma lanigerum Hausmann (Phillips, 1981;Ravensberg, 1981;Noppert et al, 1987;Mueller et al, 1988;Nicholas et al, 2005;Dib et al, 2010) and codling moth, Cydia pomonella L. (Glen, 1977). For example, excluding earwigs from woolly apple aphid or psyllid infested trees leads to a proliferation of the pests (Mueller et al, 1988;Sauphanor et al, 1993;Nicholas et al, 2005;Gobin et al, 2008). Also, in laboratory tests, He et al (2008) found that earwigs were capable of eating up to 68 apple leaf curling midge, Dasineura mali Keiffer, larvae in a single evening and trees with earwig refuges were more actively foraged for midge larvae than trees without refuges.…”

“…In laboratory tests broad-spectrum insecticides, such as chlorpyrifos, thiacloprid and spinosad, appear to be harmful to earwigs (Cisneros et al, 2002;Peusens and Gobin, 2008;Vogt et al, 2009Vogt et al, , 2010Shaw and Wallis, 2010;Logan et al, 2011) and some more selective insecticides less harmful (e.g. abamectin , Bacillus thuringiensis (Sauphanor et al, 1993), etoxazole (Beliën, 2013), pirimicarb (Ffrench-Constant andVickerman, 1985;Peusens and Gobin, 2008) and spirotetramat (Shaw and Wallis, 2010)). Although progress has been made in determining earwig sensitivity to insecticides the sensitivity of the different life stages to pesticides requires investigation (Ffrench-Constant and Vickerman, 1985).…”

Efeito de doses e de refúgio sobre a seletividade de inseticidas a predadores e parasitóides de pragas de soja

“…Entretanto, alguns autores referem impactos como mortalidade ou distúrbios de desenvolvimento ou reprodução em Amblyseius gossipi (El-Banhawy & Reda, 1988), Chrysopa carnea (Hassan et al, 1987;Zaki & Gesraha, 1987), Deraecoris brevis e Anthocoris nemoralis (Burts, 1983), e Cirrospilus vitratus (Mey, 1988). Efeitos subletais como anormalidades morfológicas e redução do peso corpóreo e da mobilidade foram observadas como efeito do diflubenzuron em Forficula auricularia por Sauphanor et al (1993).…”