-This research aimed to point out the most suitable trichogrammatid strains to control the soybean looper Pseudoplusia includes Walker. Biological parameters and parasitism ratio of 11 Trichogramma pretiosum Riley, one Trichogramma atopovirilia Oatman & Platner and one Trichogrammatoidea annulata De Santis strains reared on P. includens eggs were evaluated. Among all tested strains/species, T. pretiosum strain RV, collected in Rio Verde, GO, had the fastest development cycle and the highest percentage of parasitism of P. includens eggs. There was no difference in the parasitism and in the number of parasitoid emerged per egg among the tested parasitoid species and strains. Accordingly to the cluster analysis, T. pretiosum strain RV reared on P. includens eggs had the best performance. Considering the higher parasitism rate, shorter biological cycle, higher survival and sex ratio, T. pretiosum strain RV is the most appropriated to be used in fi eld releases aiming at P. includens control.

25, 50, 75, 100, 150, 200, 250 or 300 eggs of S. frugiperda for 24 h. Complete randomized design with ten replications was adopted. The parameters evaluated to construct the functional response curve were daily average parasitism, searching rate and oviposition time. It was observed that the higher the egg density, the higher the parasitism for 24-h and 48-h-old females although there was a tendency of parasitism stabilization at 150-egg density. The results showed a type II functional response curve for both 24-h and 48-h-old female.

In this study, the effect of temperature on the growth of the European pepper moth, Duponchelia fovealis (Zeller), was assessed at five constant temperatures (18, 21, 24, 27 and 30 °C). The European pepper moth was observed to complete its developmental stages (from egg to adult) at all the temperatures evaluated. From the results, it was evident that temperature affected the rate and development time of all the growth stages, to a significant degree. The length in time of the embryonic, larval, pupal and total (egg-adult) stages was observed to drop as the temperature rose from 18 to 24 °C, but remained constant between 27 and 30 °C. The developmental time in the pre-pupal stage dropped between 18 and 30 °C. The European pepper moth takes 454 degree-days to complete development at 11.7 °C temperature threshold. The D. fovealis survival was thus inversely proportional to temperature over range of 18 to 30 °C. On assessing the number of annual generations for the five largest strawberry-producing municipalities in Espírito Santo State, an average of 5.5 generations per year was estimated. This is a first report of temperature on D. fovealis development.

Controle químico do coró Liogenys fuscus (Blanchard 1851) (Coleoptera: Melolonthidae) na cultura do milho RESUMO -Pragas de solo como o complexo de corós são de grande importância nas culturas de milho e soja em várias regiões produtoras do Brasil, sendo que Liogenys fuscus (Blanchard) é a espécie mais comum na região Centro-Oeste. Os produtores de milho têm utilizado inseticidas para controle dessas pragas iniciais; entretanto, pouco se conhece sobre a eficiência dos diferentes inseticidas no controle de L. fuscus. Sendo assim, o objetivo do presente trabalho foi avaliar a eficiência de alguns inseticidas, aplicados no solo no sulco de plantio ou em tratamento de sementes, para o manejo de L. fuscus na cultura do milho no Estado de Goiás, durante as safras de 2004/2005 e 2005/2006. Durante a safra 2004/2005, os tratamentos testados foram clorpirifós 450, 675, 900 e 1170 g.ha -1 , endosulfan 525 g.ha -1 , fipronil 160 g.ha -1 aplicados no sulco de plantio e durante a safra 2005/2006 os tratamentos foram clorpirifós 450 e 675 g.ha -1, fipronil 160 g.ha -1 aplicados no sulco de plantio e também fipronil 37,5 e 50 g.100 kg de sementes -1 e tiametoxam 70 g.100 kg sementes -1 em tratamento de sementes. Os resultados mostraram que: clorpirifós (450,0 g.ha -1 ) pulverizado no sulco de plantio foi suficiente para o controle de L. fuscus, observando-se um estande de até sete vezes maior e um tamanho de planta de aproximadamente duas vezes maior em relação ao tratamento testemunha na safra 2004/2005 devido ao ataque da praga. Resultados semelhantes foram obtidos com fipronil (160,0 g.ha -1 ) também aplicado no sulco de plantio sendo que ambos foram superiores ao endosulfam na dose de 525,0 g.ha -1 nesta safra. Já na safra 2005/2006 não se observou incremento ao tamanho de planta e estande devido à aplicação dos inseticidas, sendo que as plantas não apresentaram sintomas de ataque da praga. Nessa safra os resultados apresentados pelos tratamentos de sementes (fipronil 37,5 e 50 g.100 kg de sementes -1 e tiametoxam 70 g.100 kg de sementes -1 ) também foram similares ao clorpirifós e fipronil na aplicação realizada no sulco de plantio, podendo, portanto ser considerada uma outra opção de controle químico para o manejo dessa praga. Sendo assim clorpirifós e fipronil aplicados no sulco de plantio além de fipronil e tiametoxam aplicados em tratamento de semente podem ser alternativas de controle químico de L. fuscus na cultura de milho em condições semelhantes ao encontrado nesses experimentos. PALAVRAS-CHAVE-Zea mays L., clorpirifós, endosulfam, fipronil, tiametoxam, pragas de solo.ABSTRACT -Soil pests such as the white grub complex are of great importance in different Brazilian regions, and Liogenys fuscus (Blanchard) is the most common species at the Brazilian Western Central Region. Corn producers had largely relied on pesticides to keep initial pest outbreaks under control, however, there is little information regarding the efficacy of different insecticides to control L. fuscus. The objective of this research was to evalua...

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An observed increase in the populations of Omiodes indicata (Fabricius) in Brazil's soybean crops is causing population outbreaks. Specimens were collected at Experimental Farm Lageado, in São Paulo State University (UNESP), Faculty of Agronomic Sciences, Botucatu, São Paulo, Brazil. Samples of individuals (larvae and pupae) were collected in the field and kept in the laboratory until emergence of adults to confirm the species. The species O. indicata occurred in four soybean areas with no previous record of this pest. The population dynamics showed that this lepidopteran is present throughout crop development, with population peaks occurring during the reproductive period of soybean. These observations are unique to this crop and planting site, showing that the insect has been adapting to the conditions of the region where it was found, demanding attention from soybean producers.

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