RESUMO

Grazing-based production systems are a source of soil greenhouse gas (GHG) emissions triggered by excreta depositions. The adoption of Urochloa forages (formerly known as Brachiaria) with biological nitrification inhibition (BNI) capacity is a promising alternative to reduce nitrous oxide (N2O) emissions from excreta patches. However, how this forage affects methane (CH4) or carbon dioxide (CO2) emissions from excreta patches remains unclear. This study investigated the potential effect of soils under two Urochloa forages with contrasting BNI capacity on GHG emissions from cattle dung deposits. Additionally, the N2O and CH4 emission factors (EF) for cattle dung under tropical conditions were determined. Dung from cattle grazing star grass (without BNI) was deposited on both forage plots: Urochloa hybrid cv. Mulato and Urochloa humidicola cv. Tully, with a respectively low and high BNI capacity. Two trials were conducted for GHG monitoring using the static chamber technique. Soil and dung properties and GHG emissions were monitored in trial 1. In trial 2, water was added to simulate rainfall and evaluate GHG emissions under wetter conditions. Our results showed that beneath dung patches, the forage genotype influenced daily CO2 and cumulative CH4 emissions during the driest conditions. However, no significant effect of the forage genotype was found on mitigating N2O emissions from dung. We attribute the absence of a significant BNI effect on N2O emissions to the limited incorporation of dung-N into the soil and rhizosphere where the BNI effect occurs. The average N2O EFs was 0.14%, close to the IPCC 2019 uncertainty range (0.01-0.13% at 95% confidence level). Moreover, CH4 EFs per unit of volatile solid (VS) averaged 0.31 g CH4 kgVS-1, slightly lower than the 0.6 g CH4 kgVS-1 developed by the IPCC. This implies the need to invest in studies to develop more region-specific Tier 2 EFs, including farm-level studies with animals consuming Urochloa forages to consider the complete implications of forage selection on animal excreta based GHG emissions.

RESUMO

This study determined the species of parasitoids of Diptera present in forest, rural, and urban areas in the municipality of Monte Alegre, MG, from March to November 2006. The percentages of parasitism in forest, rural, and urban areas were 14.3 percent, 11.0 percent, and 18.8 percent, respectively. The most frequent species (34.7 percent) was Triplasta atrocoxalis (Ashmead) (Hymenoptera: Figitidae).

Assuntos

RESUMO

This study determined the species of parasitoids of Diptera present in forest, rural, and urban areas in the municipality of Monte Alegre, MG, from March to November 2006. The percentages of parasitism in forest, rural, and urban areas were 14.3 percent, 11.0 percent, and 18.8 percent, respectively. The most frequent species (34.7 percent) was Triplasta atrocoxalis (Ashmead) (Hymenoptera: Figitidae).(AU)

Assuntos

RESUMO

The aim of this study is to report the first occurrence of the parasitoid Triplasta coxalis (Ashmead, 1865) (Hymenoptera: Figitidae: Eucoilinae) in pupae of Archisepsis scabra (Loew, 1861) (Diptera: Sepsidae) in cattle dung in Brazil. The experiment was carried out in Monte Alegre, MG. One obtained the pupae through the flotation method. They were individually placed in gelatin capsules until the emergence of the adult dipterous or their parasitoids. Fourty seven pupae of A. scabra were obtained, two of which yielded the parasitoid T. coxalis. The percentage of parasitism was 4.3 percent.

Objetivou-se, no presente trabalho, relatar a primeira ocorrência do parasitóide Triplasta coxalis (Ashmead, 1865) (Hymenoptera: Figitidae: Eucoilinae) como inimigo natural de Archisepsis scabra (Loew, 1861) (Diptera: Sepsidae) em fezes bovinas no Brasil. O experimento foi realizado em Monte Alegre, MG. As pupas foram separadas pelo método de flutuação e individualizadas em cápsulas de gelatina onde foram mantidas até a emergência dos dípteros e/ou dos parasitóides. Obtiveram-se 47 pupas de A. scabra, das quais emergiram dois parasitóides pertencentes à espécie T. coxalis. A porcentagem de parasitismo foi de 4,3 por cento.

RESUMO

ABSTRACT This paper reports the first occurrence of the parasitoid Spalangia nigra Latrielle 1805 (Hymenoptera: Pteromalidae) in pupae of Cyrtoneurina pararescita Couri 1995 (Diptera: Muscidae) in cattle dung in Brazil. The experiment was carried out in Itumbiara, state of GO, Brazil. The pupae were obtained by the flotation method. They were individually placed in gelatin capsules until the emergence of the adult flies or their parasitoids. The percentage of parasitism was 10%.

RESUMO Este trabalho relata a primeira ocorrência do parasitóide Spalangia nigra Latrielle 1805 (Hymenoptera: Pteromalidae) sobre pupas de Cyrtoneurina pararescita Couri 1995 (Diptera: Muscidae) em fezes bovinas no Brasil. O experimento foi realizado em Itumbiara, GO. As pupas foram obtidas pelo método de flutuação, individualizadas em cápsulas de gelatina e mantidas até a emergência das moscas e/ou parasitóides. A porcentagem de parasitismo foi de 10%.

RESUMO

RESUMO Este estudo relata a ocorrência de superparasitismo em pupas de Cyrtoneurina pararescita Couri (Diptera: Muscidae) pelo parasitóide Spalangia nigroaenea Curtis (Hymenoptera: Pteromalidae) em fezes bovinas em Itumbiara, Goiás, Brasil. Amostras de fezes foram coletadas em intervalos de duas semanas de sua exposição no campo, levadas para o laboratório para extração das pupas pelo método de flutuação. As pupas foram individualizadas em cápsulas de gelatina e mantidas até a emergência das moscas e/ou parasitóides. Foram coletadas duas pupas de C. pararescita, das quais de cada uma emergiram 2 parasitóides pertencentes a espécie S. nigroaenea. Este é o primeiro relato de superparasitismo de S. nigroaenea em pupas de C. pararescita em fezes bovinas no Brasil.

ABSTRACT This study reports the occurrence of superparasitism in pupae of Cyrtoneurina pararescita Couri (Diptera: Muscidae) by the parasitoid Spalangia nigroaenea Curtis (Hymenoptera: Pteromalidae) in bovine dung in Itumbiara, Goias, Brazil. Manure samples, collected at two intervals, were taken to the laboratory and the pupae were extracted by water flotation. The pupae were placed in gelatin capsules until the emergence of flies or their parasitoids. Parasitoids of the species S. nigroaenea emerged from two of the pupae. This is the first report of superparasitism by S. nigroaenea in pupae of C. pararescita in bovine dung in Brazil.

RESUMO

The frequency of Pteromalidae species found in Diptera pupae that were collected from cattle dung in Panamá, State of Goiás, Brazil, between May and December 2003 was studied. The pupae were obtained by the flotation method and were individually placed in gelatin capsules until the emergence of the adult flies or their parasitoids. The overall percentage of parasitism was 14.7%. The percentage of parasitism presented by the parasitoids Pachycrepoideus vindemmiae (Rondani), Spalangia cameroni Perkins, Spalangia drosophilae Ashmead , Spalangia endius Walker, Spalangia nigra Latrielle and Spalangia nigroaenea Curtis were 1.7%, 1.4%, 2.4%, 0.7%, 2.4% and 6.1%, respectively.(AU)

Assuntos

RESUMO

This study had the objective of determining the species of microhimenopterous in pupae of Diptera present in cattle dung, collected in the county of Itumbiara, GO, Cachoeira Dourada, GO and Panamá, GO, from January 1998 to June 2004. The dipterous pupae were obtained by the flotation method. They were individually placed in gelatin capsules until the emergence of the flies and/or their parasitoids. The overall prevalence of parasitism was 7.36%. The species more frequent were: Spalangia drosophilae Ashmead (Hymenoptera: Pteromalidae) with 30.8% e Triplasta atrocoxalis Ashmead (Hymenoptera: Figitidae) with 16.2%.

Este estudo teve como objetivo determinar as espécies de microhimenópteros parasitóides em pupas de Diptera presentes em fezes bovinas, coletadas nos municípios de Itumbiara, Cachoeira Dourada, e Panamá, GO, no período de janeiro de 1998 a junho de 2004. As pupas dos dípteros foram isoladas pelo método de flotação, individualizadas em cápsulas de gelatina até a emergência das moscas e/ou dos seus parasitóides. A porcentagem total de parasitismo observada foi de 7,36%. As espécies mais freqüentes foram: Spalangia drosophilae Ashmead (Hymenoptera: Pteromalidae) com 30,8% e Triplasta atrocoxalis Ashmead (Hymenoptera: Figitidae) com 16,2%.

RESUMO

A coleta de Diptera em fezes bovinas depositadas nas pastagens foi conduzida de janeiro a agosto de 2001 em Itumbiara, Goiás. As fezes foram expostas nas pastagens por 24, 48, 72, 96, 120, 144, 168, 192, 216 e 240 horas e posteriormente levadas para laboratório para extração e separação dos dípteros. Um total de 100 fezes bovinas foram expostas nas pastagens, das quais 3099 dípteros muscóides foram coletados. As espécies mais abundantes foram: Palaeosepsis spp. e Sarcophagula occidua. A maioria dos exemplares foi coletada em fezes bovinas expostas nos períodos de 72 e 144 horas no campo.(AU)

Assuntos

RESUMO

Dung beetles were collected in pasture areas in Piracicaba (State of São Paulo), Aquidauana (State of Mato Grosso do Sul) and Capão do Leão (State of Rio Grande do Sul). In the first two sites, the beetles were collected in pitfall traps, while in the third site they were collected in a light trap. Mites of the families Scutacaridae and Pygmephoridae were commonly found on those beetles. In the family Scutacaridae, the following species were found: Pygmodispus (Pygmodispus) bicornutus Ebermann & Rodrigues, Scutacarus longitarsus (Berlese) and Scutacarus sp. In the family Pygmephoridae, the following genera were found: Elattoma, Bakerdania, Elattosoma, Pediculaster sp. near brasiliensis and Sicilipes. Only female mites were collected.

Besouros coprófagos foram coletados em áreas de pastagem em Piracicaba (Estado de São Paulo), Aquidauana (Estado de Mato Grosso do Sul) e Capão do Leão (Estado de Rio Grande do Sul). Nas duas primeiras localidades, os besouros foram coletados em armadilhas pitfall, enquanto que na terceira localidade foram coletados em armadilha luminosa. Acaros das famílias Scutacaridae e Pygmephoridae foram encontrados comumente nos besouros. Na família Scutacaridae, as seguintes espécies foram encontradas: Pygmodispus (Pygmodispus) bicornutus Ebermann & Rodrigues, Scutacarus longitarsus (Berlese) e Scutacarus sp. Na família Pygmephoridae, os seguintes gêneros foram encontrados: Elattoma, Bakerdania, Elattosoma, Pediculaster sp. aff. brasiliensis e Sicilipes. Apenas ácaros fêmeas foram coletados.

RESUMO

This work reports, for the first time, the occurrence of Triplasta atrocoxalis (Hymenoptera: Eucoilidae) parasitizing pupae of Cyrtoneurina pararescita (Diptera: Muscidae) in cattle dung in Brazil.

RESUMO

Four hymenopterous parasitoids were found from Cyrtoneurina pararescita Couri pupae: Spalangia cameroni Perkins, Spalangia endius Walker, Spalangia nigroaenea Curtis and Spalangia sp. The predominant parasitoids of C. pararescita was S. nigroaenea. These parasitoids accounted for 0.63% of the parasitism.