Age and Morphological Changes in the Epiponini Wasp Polybia paulista Von Ihering (Hymenoptera: Vespidae)

The division of labor is a central theme in the study of social insects. In bees and wasps, this activity is regulated by age polyethism. Important physiological and morphological changes have been widely studied in the polyethism of honeybee workers. In contrast, this is a relatively unexplored subject in social vespids. Our goal was to determine if there are detectable morphological changes in the body of the Epiponini wasp Polybia paulista Von Ihering or in certain glands in relation to age polyethism. We observed changes in the body weight, the salivary gland, and the mandibular gland that were associated with age, and our results suggest that social relationships and task performance are important to these changes. This contrasts with observations in Polistes and is different from the Apis mellifera Linnaeus age polyethism model. © 2013 Sociedade Entomológica do Brasil.

A survey of DNA methylation across social insect species, life stages, and castes reveals abundant and caste-associated methylation in a primitively social wasp

DNA methylation plays an important role in the epigenetic control of developmental and behavioral plasticity, with connections to the generation of striking phenotypic differences between castes (larger, reproductive queens and smaller, non-reproductive workers) in honeybees and ants. Here, we provide the first comparative investigation of caste- and life stage-associated DNA methylation in several species of bees and vespid wasps displaying different levels of social organization. Our results reveal moderate levels of DNA methylation in most bees and wasps, with no clear relationship to the level of sociality. Strikingly, primitively social Polistes dominula paper wasps show unusually high overall DNA methylation and caste-related differences in site-specific methylation. These results suggest DNA methylation may play a role in the regulation of behavioral and physiological differences in primitively social species with more flexible caste differences. © 2013 Springer-Verlag Berlin Heidelberg.

Toxicidade de Lantana camara (Verbenaceae) em operárias de Apis mellifera (Hymenoptera: Apidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Efeito da infestação do ácaro Varroa destructor (Anderson e Treuman, 2000) (Arachnida : Acari : Varroidae) no desenvolvimento de abelhas africanizadas Apis mellifera (Linnaeus, 1758) (Hymenoptera: Apidae)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da própolis sobre a produção de citocinas por camundongos submetidos a estresse crônico e desafiados com melanoma

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Efeito da cafeína no comportamento e na longevidade de operárias de abelhas africanizadas Apis mellifera L. (Hymenoptera: Apidae)

Pós-graduação em Ciências Biológicas (Zoologia) - IBRC

Efeito de recurso floral na composição qualitativa de apitoxina

Pós-graduação em Zootecnia - FMVZ

Influence of agrochemicals fipronil and imidacloprid on the learning behavior of Apis mellifera L. honeybees

Agrochemicals on crop cultivated areas is a source of contamination for bees and may cause physiological and behavioral disorders and mortality. The LD50 of the pesticides fipronil and imidacloprid was determined and their effect on the learning behavior of Apis mellifera L. honeybee evaluated. LD50 was determined by the ingestion of contaminated food with different concentrations of insecticide concentrations: Fipronil (0, 0.8, 0.4, 0.2, 0.1 and 0.05 µg bee-1) and imidacloprid (0, 0.4, 0.2, 0.1, 0.05 and 0.025 µg bee-1). The method of proboscis extension reflection (PER) and learning through citral odor evaluated their responses to food stimulation. LD50 obtained were 0.28 ± 0.11 and 0.10 ± 0.04 µg bee-1 for fipronil and imidacloprid, respectively. The PER test showed no significant difference (p < 0.05) although agrochemicals affected the learning of bees. Insecticides fipronil and imidacloprid are extremely harmful to foraging Africanized Apis mellifera bees.

Increased brood viability and longer lifespan of honeybees selected for propolis production

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Africanized honeybees in urban areas: a public health concern

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Modification of the brain proteome of Africanized honeybees (Apis mellifera) exposed to a subaEurolethal doses of the insecticide fipronil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Análises morfológica e histoquímicas do ventrículo e do cérebro de operárias recém emergidas de Apis Mellifera L. (Hymenoptera, Apidae) tratadas com Thiamethoxam

Apis mellifera honeybees are social insects of economic importance, by providing honeybee products, and by the pollination of natural areas of vegetation or agricultural areas. The constant use of pesticides, including the thiamethoxam, which is an insecticide belonging to the class of neonicotinoids with neurotoxic action, is subjecting pollinators to situations of severe stress, which has been evidenced by the decrease in the density of honeybees in many parts of the world. By these considerations, the present study aimed to assess the acute toxicity of thiamethoxam for newly emerged workers of A. mellifera, and to investigate the effect of sublethal doses of this insecticide on the survival time and its cytotoxicity to the brain and midgut to the honeybees. It was established the value of the lethal concentration 50 (LC50) equal to 4.28 ng thiamethoxam/μL of food and from it, the sublethal concentrations of 0.428 ng thiamethoxam/μL (CL50/10) and 0.0428 ng thiamethoxam/μL (CL50/100), which were used in bioassays of intoxication of the honeybees. After the bioassays the bees were dissected and the brain and midguts were collected to analyze possible morphological (staining with Hematoxylin-Eosin) and histochemical alterations (Xylidine Ponceau technique, and Feulgen and PAS reactions) caused by exposure to thiamethoxam, and to calculate the lethal time (LT50) for the workers. The duration of the bioassays was 8 days after beginning of feeding. The results obtained showed that the thiamethoxam is toxic to newly-emerged workers of A. mellifera, causing changes in survival time of individuals. This study also shown that the thiamethoxam causes morphological and histochemical alterations on the midgut and brain of workers. These alterations may be reflected in physiological and behavioral changes that can modify the operation of the colony

Desenvolvimento de uma plataforma analítica para aquisição de imagens moleculares em tecidos animais

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The genomes of two key bumblebee species with primitive eusocial organization

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Avaliação bioquímica e imunohistoquímica dos efeitos subletais do tiametoxam sobre Apis mellifera (Hymenoptera, Apidae)

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)