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The Borer moth Crocidosema aporema (Walshingham J9/4) (Lepidoptera: Tortricidae) is a potentially harmful species to the soybean crops, particularly in the areas of temperate weather, like those in the southernmost section of Rio Grande do Sul State. Level of damage caused on the late crops of the season is influenced by sowing time and varies according to the genotype. Currently the available information in Brazil pertinent to the variaton on C. aporema onslaught on commercial genotypes is scarce. This paper evaluated the damage provoked on late-season crops upon eighteen soybean commercial genotypes, compared in two groups according to relative maturity degree (RMD), in the V.4, V.6, V.8, V.10, R.2 and R.4 phenological states, during the agricultural year 2009/ 2010, in the Campanha Region of Rio Grande do Sul. Significant differences on attack levels were found among the longer cycle genotypes, being the 'Fundacep 59' cultivar the least attacked in this group and 'Fepagro RS-IO' and 'Fundacep 45 - Missions' cultivars the genotypes presenting the highest damage to the crops. Level of damage varied differently according to the phenological stage for each genotype; there were cultivars suffering from highest attack levels during their vegetative stages and cultivars under heavier attack on reproductive stages. Monitoring of damage to the late-season crops identified only once, in the 'Fepagro RS-10' cultivar, the need for control adoption, when the level of 30% of attacked crops by C. aporema was reached. [ABSTRACT FROM AUTHOR]

This research aimed to evaluate the effect of nineteen pesticides used in peach orchards on eggs and pupae of the predator Chrysoperla externa in bioassays carried under laboratory conditions (temperature of 25±1°C, relative humidity 70±10% and 14 hours photophase). The pesticides were directly sprayed on eggs and pupae trough a Potter tower using the maximum recommended dosage for peach orchards. It was evaluated eggs and pupae viability, in addition to fecundity and fertility of adults emerged from treated pupae. The pesticides were classified to eggs according to reduction in eggs hatch, and to pupae according to the total effect into IOBC toxicity categories. Most of pesticides evaluated (8 insecticides, 8 fungicides and 2 herbicides) were harmless (category 1) to eggs and pupae, with a reduction in eggs hatch and total effect to pupae lower than 30%, except for the insecticide mineral oil, which reduced eggs hatch in 69.55% and caused a total effect of36.22% in pupae, being therefore classified as slightly harmful (category 2) to eggs and pupae of C. externa. [ABSTRACT FROM AUTHOR]