Seletividade de inseticidas para ovos e ninfas de Orius insidiosus (Say) (Hemiptera: Anthocoridae)

Abstract

-The predator Orius insidiosus (Say) feeds on thrips, aphids, whiteflies, mites and small caterpillars and contributes to regulate the population of these pests in different agroecossystems. The present research aimed to evaluate the selectivity of the pesticides abamectin, cartap, cyromazine, fenpropathrin and imidacloprid, which are registered for chrysanthemum crops, to eggs and first-, second-and third-instar nymphs of O. insidiosus. A Potter tower was used to spray the insecticides on the eggs and nymphs at the highest recommended rates. After spraying, the individuals were kept under controlled conditions at 25 ± 1 o C, 70 ± 10% RH and 12h photophase. The effects of the pesticides on the embryonic period, on egg viability, instar duration and nymph survival were evaluated. The eggs of O. insidiosus were tolerant to all pesticides. Both cartap and cyromazine were selective, whereas abamectin, fenpropathrin and imidacloprid were toxic to all tested instars of O. insidiosus. Fenpropathrin was the most toxic pesticide and killed 100% of the nymphs. The insecticides cartap and cyromazine can be recommended for integrated pest management programs in chrysanthemum crops.KEY WORDS: Toxicity, biological control, chrysanthemum RESUMO -O predador Orius insidiosus (Say) alimenta-se de tripes, afídeos, moscas-brancas, ácaros e pequenas lagartas, contribuindo para a regulação populacional dessas pragas em diferentes agroecossistemas. Este trabalho teve por objetivo avaliar a seletividade dos inseticidas abamectina, cartape, ciromazina, fempropatrina e imidaclopride, registrados para a cultura do crisântemo, para ovos e ninfas

Lethal and Sublethal Effects of Fenpropathrin on the Biological Performance of <I>Scolothrips longicornis</I> (Thysanoptera: Thripidae)

“…Fenpropathrin has also been shown to negatively affect T. pyri (Solomon et al 1993), Deraeocoris lutescens Schilling (Heteroptera: Miridae) (Azimizadehi et al 2012), and natural enemies of Bemisia tabaci (Gennadius) (Homoptera: Aleyrodidae) (Bacci et al 2007). This supports the general adverse lethal and sublethal effects of fenpropathrin on reproduction, mating behavior, egg development, oviposition, and egg hatch in many insect and mite species (Carvalho et al 2005, Villanueva and Walgenbach 2005, Bacci et al 2007, Azimizadehi et al 2012.…”

“…In addition, further studies under higher tiers (semiÞeld and Þeld conditions) with experiments involving multiple routes of exposure (topical, residual, and ingestion) as well as mixed age classes (Kim et al 2006) will be needed for a full ecotoxicological evaluation of fenpropathrin on predatory thrips in agroecosystems (Stark et al 1995, Sterk et al 1999, Biondi et al 2012). The present research, although using concentrations lower than the recommended Þeld rate for T. urticae control, has demonstrated adverse effects of sublethal concentrations on the performance of S. longicornis even for the lowest concentrations that have previously been suggested for use in combination with biological control agents within IPM systems (Carvalho et al 2005).…”