Persistência de agrotóxicos utilizados na cultura do milho ao parasitoide Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae)

Abstract

II Persistência de agrotóxicos utilizados na cultura do milho ao parasitoide

Impact of insecticides used to control Spodoptera frugiperda (J.E. Smith) in corn on survival, sex ratio, and reproduction of Trichogramma pretiosum Riley offspring

“…These authors also classified chlorfenapyr as slightly harmful (class 2). Stefanello Júnior et al (2008a) showed that triflumuron did not affect T. pretiosum parasitism capacity when tested females were exposed to triflumuron-treated host eggs; this was similar to the findings of the present Sterk et al (1999) in which class 1 = harmless, class 2 = slightly harmful, class 3 = moderately harmful, and class 4 = harmful. 3 Figures followed by the same letter, lower case in columns and upper case in rows, show no differences between them according to Scott-Knott test (P > 0.05) (Scott and Knott, 1974); CVmaternal generation (%) = 35.9 and CVF1 generation (%) = 27.2.…”

“…When chlorpyrifostreated host eggs were offered to these females 48 h after treatment, a decrease of 96.9% was observed in parasitism capacity and the compound was considered moderately harmful (class 3) (Table 1). Moura et al (2006) andStefanello Júnior et al (2008a;2008b) also observed that chlorpyrifos drastically reduced T. pretiosum parasitism capacity and classified the pesticide as harmful (class 4).…”

Selectivity of pesticides used in rice crop on Telenomus podisi and Trichogramma pretiosum

“…This is highly relevant, given that weeds are the main limiting factor for rice yield, and weed control is generally performed using herbicides (Sosbai 2014). Low toxicity to egg parasitoids in different developmental stages was also reported for herbicides registered for soybean (Carmo et al 2009, Magano et al 2013) and maize (Stefanello Júnior et al 2008b and.…”

“…and Trichogramma spp. (Moura et al 2006, Giolo et al 2007, Stefanello Júnior et al 2008a, Preetha et al 2009, Carmo et al 2010, Koppel et al 2011, Goulart et al 2012, Oliveira et al 2013. As reported by Stefanello Júnior et al (2008a), this toxicity originates from the similarity in the transmission mode of nerve impulses not only between the different orders of insects, but also between the various animal phyla.…”

“…Some of the hosts are the eggs of the Asiatic rice borer Chilo suppressalis (Walker) (Lepidoptera: Crambidae) (Chen et al 2010, Ko et al 2014, the rice leafroller Cnaphalocrocis medinalis (Guenee) (Lepidoptera: Pyralidae) (Gurr et al 2012) and the rice yellow stem borer Scirpophaga incertulas (Walker) (Lepidoptera: Crambidae) (Guo et al 2002), among others. In Brazil, several species of Trichogramma have been described (Querino & Zucchi 2003), and Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) is one of the most used for controlling Lepidoptera pests (Brugger et al 2010, Stefanello Júnior et al 2012.…”