Development and reproduction of Podisus nigrispinus (Hemiptera: Pentatomidae) fed with Thyrinteina arnobia (Lepidoptera: Geometridae) reared on guava leaves

The aim of this study was to evaluate the development and reproduction of P. nigrispinus in laboratory when fed with T. arnobia reared on guava leaves. This predator showed nymphal stage of 21.11 days, survival of 60 percent and periods of pre-oviposition, number of eggs/mass and eggs/female and egg viability of 6.10 days, 26.24 eggs, 314.90 eggs and 82.65 percent, respectively. These results demonstrated that T. arnobia fed with guava leaves was an adequate supply of food to P.nigrispinus.

Parasitismo e sítios de diapausa de adultos do percevejo marrom, Euschistus heros na região da grande Dourados, MS / Parasitism and diapause sites of brown stink bug adults, Euschistus heros in the great Dourados region, MS, Brazil

Entre os insetos que atacam a soja, o percevejo marrom Euschistus heros (Fabricius) é considerado uma das principais pragas. Os objetivos deste trabalho foram avaliar a ocorrência de parasitismo em adultos do percevejo marrom E. hero, no período de cultivo da soja e de entressafra, e identificar seus sítios de diapausa no período de entressafra, na região da Grande Dourados, Mato Grosso do Sul (MS). Foram coletados adultos do percevejo em lavouras de soja, durante as safras 2004/05 e 2005/06, sendo as coletas realizadas semanalmente. No período de entressafra da soja de 2005 e 2006, foram realizadas inspeções em diferentes ambientes vegetais visando a constatar possíveis sítios de diapausa do percevejo, bem como avaliar a ocorrência de parasitismo nesses ambientes. Em cada coleta, foram individualizados 40 adultos em caixas gerbox contendo Ligustrum lucidum Ait. (Oleraceae), sendo os insetos observados durante um período de 40 dias. Os parasitoides foram armazenados em álcool 70 por cento e encaminhados para identificação. O índice natural de parasitismo de adultos de E. heros amostrados no período de safra e de entressafra de soja variou de 0,0 a 5,0 por cento, considerando-se as diferentes coletas realizadas, sendo Hexacladia smithii Ashmead (Hymenoptera: Encyrtidae) a única espécie de parasitoide ocorrente. No período de entressafra, foi verificada maior incidência do percevejo E. heros em folhas secas de mangueira (Mangifera indica L.) caídas no chão, evidenciando que esse ambiente é um importante sítio de diapausa para essa praga na região.

Among the insects that attack soybeans, brown stink bug Euschistus heros (Fabricius) is considered a major pest. The aim of this research was to evaluate the occurrence of parasitism in adults of brown stink bugs E. heros during soybean crop season and to identify diapause sites during the period of soybean absence in the great region of Dourados, MS. Adults of brown stick bugs were collected weekly in soybean crops during the 2004/05 and 2005/06 growing seasons. In the off-season soybean in 2005 and 2006 inspections were conducted in different environments to find possible sites of bugs' diapause , and to evaluate the occurrence of parasitism in these environments. For each sampling date, 40 adults were put inside one gerbox, fed with Ligustrum lucidum Ait. (Oleraceae), and observed for a period of 40 days. Parasitoids were kept in alcohol 70 percent and send to identification. The natural incidence of parasitism of adults collected in the period with and without soybean crops varied from 0.0 percent and 5.0 percent, and considering different samples, Hexacladia smithii Ashmead (Hymenoptera: Encyrtidae) was the only one parasitoid found. During the period of soybean absence was observe the highest incidence of E. heros on dry fallen leaves of Mangifera indica L., showing that this environment is an important diapause sites for this pest in this region.