ABSTRACT
The aim of this paper is to present the termite impact on sampled soil structures during a controlled experiment. The structures used were sampled in a red yellow Latosol. The Cornitermes cumulans colonies were sampled in the same site and were maintained in controlled conditions during 9 months. Two types of structures were tested: dense macrostructures and a strong granular structure sampled in the same site than the colonies. Two replicates of the conceptual termite-structure model were developed. Two pots, one of them with the colony and food material, the second with the same structured material and food, composed each replicate; a tube associated the two pots. Macro and micromorphological descriptions were done, the distribution and localization of galleries were described and compared with those sampled at field. The termites colonies maintained their exploring and construction activities, during the period, with some restrictions. In the experimental model with dense macrostructures the activities were important and equivalent in all of the volumes. But, in the experimental model with the strong granular structure the activities were essentially done in the volumes with the mounds. The new structures that were built, soil particles were oriented, and formed rigid walls as they were observed in field samples. C. cumulans colonies explored the volume aleatory in all dire
O objetivo deste trabalho foi avaliar o comportamento de térmitas em estruturas oriundas de um Latossolo Vermelho Amarelo. Ninhos em atividade de Cornitermes cumulans (Isoptera, Nasutitermitinae) foram coletados a campo e mantidos em vasos em casa de vegetação por nove meses. As estruturas utilizadas no experimento foram macroestruturas densas e estrutura granular, ambas amostradas no mesmo solo que as colônias. O experimento foi realizado com duas repetições para cada estrutura, sendo cada repetição composta de um vaso com estrutura, ninho e alimento, e um vaso com a mesmo material e alimentação. As estruturas fabricadas pelos térmitas foram descritas macro e micromorfologicamente e comparadas com amostras coletadas no campo, também se verificou a distribuição das galerias. Os térmitas mantiveram as atividades de forrageamento e construção do ninho até o final do experimento, com algumas restrições. Para os vasos com estruturas densas a atividade desenvolveu-se tanto no vaso onde havia o ninho quanto no vaso com alimentação. Em comparação, para os vasos com estrutura granular as construções foram menos desenvolvidas e localizadas nos volumes associados aos ninhos. Nas estruturas construídas, as partículas de solo eram orientadas, formando uma parede rígida, como observado em feições coletadas no campo. As colônias de C. cumulans exploravam o ambiente de forma aleatória em tod
ABSTRACT
Insect pests have not been recorded for amaranth (Amaranthus cruentus L.) in Brazil. Generalized plant lodging was observed after the grain-filling period in an irrigated commercial amaranth crop (7 ha), located in Cristalina, state of Goiás (Brazil), which was cultivated between Aug. and Dec. 2009. Almost all sampled plants presented internal galleries bored by lepidopteran larvae. The larvae were reared, and the adults were identified as Herpetogramma bipunctalis (F.) (Crambidae). This is the first report of an insect pest causing significant damage in a commercial amaranth crop in Brazil, which indicates the need to develop pest management strategies in order to support the increased production in Brazil.
ABSTRACT
Insect pests have not been recorded for amaranth (Amaranthus cruentus L.) in Brazil. Generalized plant lodging was observed after the grain-filling period in an irrigated commercial amaranth crop (7 ha), located in Cristalina, state of Goiás (Brazil), which was cultivated between Aug. and Dec. 2009. Almost all sampled plants presented internal galleries bored by lepidopteran larvae. The larvae were reared, and the adults were identified as Herpetogramma bipunctalis (F.) (Crambidae). This is the first report of an insect pest causing significant damage in a commercial amaranth crop in Brazil, which indicates the need to develop pest management strategies in order to support the increased production in Brazil.
ABSTRACT
The aim of this paper is to present the termite impact on sampled soil structures during a controlled experiment. The structures used were sampled in a red yellow Latosol. The Cornitermes cumulans colonies were sampled in the same site and were maintained in controlled conditions during 9 months. Two types of structures were tested: dense macrostructures and a strong granular structure sampled in the same site than the colonies. Two replicates of the conceptual termite-structure model were developed. Two pots, one of them with the colony and food material, the second with the same structured material and food, composed each replicate; a tube associated the two pots. Macro and micromorphological descriptions were done, the distribution and localization of galleries were described and compared with those sampled at field. The termites colonies maintained their exploring and construction activities, during the period, with some restrictions. In the experimental model with dense macrostructures the activities were important and equivalent in all of the volumes. But, in the experimental model with the strong granular structure the activities were essentially done in the volumes with the mounds. The new structures that were built, soil particles were oriented, and formed rigid walls as they were observed in field samples. C. cumulans colonies explored the volume aleatory in all dire
O objetivo deste trabalho foi avaliar o comportamento de térmitas em estruturas oriundas de um Latossolo Vermelho Amarelo. Ninhos em atividade de Cornitermes cumulans (Isoptera, Nasutitermitinae) foram coletados a campo e mantidos em vasos em casa de vegetação por nove meses. As estruturas utilizadas no experimento foram macroestruturas densas e estrutura granular, ambas amostradas no mesmo solo que as colônias. O experimento foi realizado com duas repetições para cada estrutura, sendo cada repetição composta de um vaso com estrutura, ninho e alimento, e um vaso com a mesmo material e alimentação. As estruturas fabricadas pelos térmitas foram descritas macro e micromorfologicamente e comparadas com amostras coletadas no campo, também se verificou a distribuição das galerias. Os térmitas mantiveram as atividades de forrageamento e construção do ninho até o final do experimento, com algumas restrições. Para os vasos com estruturas densas a atividade desenvolveu-se tanto no vaso onde havia o ninho quanto no vaso com alimentação. Em comparação, para os vasos com estrutura granular as construções foram menos desenvolvidas e localizadas nos volumes associados aos ninhos. Nas estruturas construídas, as partículas de solo eram orientadas, formando uma parede rígida, como observado em feições coletadas no campo. As colônias de C. cumulans exploravam o ambiente de forma aleatória em tod