RESUMO

Africanized Apis mellifera colonies with promising characteristics for beekeeping have been detected in northern Argentina (subtropical climate) and are considered of interest for breeding programs. Integral evaluation of this feral material revealed high colony strength and resistance/tolerance to brood diseases. However, these Africanized honeybees (AHB) also showed variable negative behavioral traits for beekeeping, such as defensiveness, tendency to swarm and avoidance behavior. We developed a protocol for the selection of AHB stocks based on defensive behavior and characterized contrasting colonies for this trait using NGS technologies. For this purpose, population and behavioral parameters were surveyed throughout a beekeeping season in nine daughter colonies obtained from a mother colony (A1 mitochondrial haplotype) with valuable characteristics (tolerance to the mite Varroa destructor, high colony strength and low defensiveness). A Defensive Behavior Index was developed and tested in the colonies under study. Mother and two daughter colonies displaying contrasting defensive behavior were analyzed by ddRADseq. High-quality DNA samples were obtained from 16 workers of each colony. Six pooled samples, including two replicates of each of the three colonies, were processed. A total of 12,971 SNPs were detected against the reference genome of A. mellifera, 142 of which showed significant differences between colonies. We detected SNPs in coding regions, lncRNA, miRNA, rRNA, tRNA, among others. From the original data set, we also identified 647 SNPs located in protein-coding regions, 128 of which are related to 21 genes previously associated with defensive behavior, such as dop3 and dopR2, CaMKII and ADAR, obp9 and obp10, and members of the 5-HT family. We discuss the obtained results by considering the influence of polyandry and paternal lineages on the defensive behavior in AHB and provide baseline information to use this innovative molecular approach, ddRADseq, to assist in the selection and evaluation of honey bee stocks showing low defensive behavior for commercial uses.

RESUMO

Royal jelly is an essential substance for the development of bees from larval to adult stages. Studies have identified a group of key proteins in royal jelly, denominated major royal jelly proteins (MRJPs). The group currently consists of nine proteins (MRJP1-MRJP9), with MRJP1 being the most abundant and MRJP3 being used as a microsatellite marker for the selection of queens with a greater production of royal jelly. The diet of bees is mostly composed of proteins, and supplementing this intake to encourage a higher production of their primary product is important for producers. It is estimated that, by adding probiotic and prebiotic organisms to their diets, the benefits to bees will be even greater, both for their immune systems and primary responses to stress. Circumstances that are adverse compared to those of the natural habitat of bees eventually substantially interfere with bee behavior. Stress situations are modulated by proteins termed heat shock proteins (HSPs). Among these, HSP70 has been shown to exhibit abundance changes whenever bees experience unusual situations of stress. Thus, we sought to supplement A. mellifera bee colony diets with proteins and prebiotic and probiotic components, and to evaluate the expression levels of MRJP3 and HSP70 mRNAs using qRT-PCR. The results revealed that differences in the expression of MRJP3 can be attributed to the different types of feed offered. Significant differences were evident when comparing the expression levels of MRJP3 and HSP70, suggesting that protein supplementation with pre/probiotics promotes positive results in royal jelly synthesis carried out by honey bee nurses.

RESUMO

Analysis of the mtDNA variation in Apis mellifera L. has allowed distinguishing subspecies and evolutionary lineages by means of different molecular methods; from RFLP, to PCR-RFLP and direct sequencing. Likewise, geometric morphometrics (GM) has been used to distinguish Africanized honey bees with a high degree of consistency with studies using molecular information. High-resolution fusion analysis (HRM) allows one to quickly identify sequence polymorphisms by comparing DNA melting curves in short amplicons generated by real-time PCR (qPCR). The objective of this work was to implement the HRM technique in the diagnosis of Africanization of colonies of A. mellifera from Argentina, using GM as a validation method. DNA was extracted from 60 A. mellifera colonies for mitotype identification. Samples were initially analyzed by HRM, through qPCRs of two regions (485 bp/385 bp) of the mitochondrial cytochrome b gene (cytb). This technique was then optimizing to amplify a smaller PCR product (207 bp) for the HRM diagnosis for the Africanization of colonies. Of the 60 colony samples analyzed, 41 were classified as colonies of European origin whereas 19 revealed African origin. All the samples classified by HRM were correctly validated by GM, demonstrating that this technique could be implemented for a rapid identification of African mitotypes in Apis mellifera samples.

Assuntos

RESUMO

Africanized honey bee populations (Apis mellifera L.) have been decreasing mainly due to the intense use of synthetic insecticides associated with pollution and climate change. To minimize these impacts on the environment and bee populations, the use of biological control agents has been intensified. These products are generally safer for non-target insects, such as bees, which are important pollinating insects. Thus, the objective of this study was to evaluate the impact of entomopathogenic nematodes on the longevity of the Africanized honey bee A. mellifera workers. Seven treatments were used: Heterorhabditis amazonensis, Heterorhabditis bacteriophora, Heterorhabditis indica, Steinernema carpocapsae, Steinernema feltiae, and Steinernema rarum, at a concentration of 40 infective juveniles per cm² (IJs/cm²), and a control in which autoclaved distilled water was used. Two bioassays were performed: 1) spraying nematodes on the workers and 2) spraying nematodes on glass plates, in which the bees remained for two hours. Each treatment consisted of five replicates with 20 bees each. Bees were kept in cages of PVC (20 × 10 cm) covered with a voile fabric and provided pieces of cotton soaked in water and Candy paste. The cages were kept in a climatized room (27 ± 2 °C temperature, 60 ± 10% relative humidity, and 12 h photophase) and the mortality was evaluated from 12 to 240 hours. In bioassay 1, the three treatments with nematodes of the genus Steinernema reduced the longevity of the workers (103.9, 96.3, and 99.6 h) when compared to treatments with Heterorhabditis (149.7, 126.8, and 134.7 h), of which, only H. amazonensis (149.7 h) did not differ from the control (166.0 h). In bioassay 2, all treatments reduced the longevity of honey bees (155.4 to [...].

As populações de abelhas africanizadas (Apis mellifera L.) vêm diminuindo devido, principalmente, ao intenso uso de inseticidas sintéticos. Desde modo, o emprego de agentes de controle biológico tem-se intensificado de forma a minimizar este impacto no ambiente. Estes produtos são, de modo geral, mais seguros aos insetos não-alvos, como as abelhas que são importantes insetos polinizadores. Desta forma, o objetivo deste trabalho foi avaliar os efeitos de nematoides entomopatogênicos utilizados para controle de insetos pragas, sobre a longevidade de operárias de A. mellifera africanizada. Foram utilizados sete tratamentos: Heterorhabditis amazonensis, Heterorhabditis bacteriophora, Heterorhabditis indica, Steinernema carpocapsae, Steinernema feltiae e Steinernema rarum, na concentração de 40 juvenis infectantes por cm² (JIs/cm²), e como testemunha água destilada autoclavada. Para isso foram realizados dois bioensaios: 1) Pulverização dos nematoides sobre as operárias e 2) Pulverização dos nematoides em placas de vidro, nas quais as abelhas permaneceram por duas horas em contato. Cada tratamento foi composto por cinco repetições com 20 abelhas cada. As abelhas foram mantidas em gaiolas de PVC (20x10cm) cobertas com tecido voile e fornecidos pedaços de algodão embebido em água e pasta Candy. As gaiolas foram mantidas em sala climatizada (27 ± 2 °C, U.R. 60 ± 10%, fotofase de 12h) e a mortalidade avaliada de 12 até 240 horas. No bioensaio 1 os três tratamentos com nematoides do gênero Steinernema reduziram a longevidade das operárias (103,9; 96,3 e 99,6 horas) quando comparados aos tratamentos com Heterorhabditis (149,7; 126,8 e 134,7 horas). Entretanto, dentre estes apenas H. amazonensis (149,7 horas) não diferiu da testemunha (166,0 horas). No bioensaio 2, todos os [...].

Assuntos

RESUMO

Africanized honey bee populations (Apis mellifera L.) have been decreasing mainly due to the intense use of synthetic insecticides associated with pollution and climate change. To minimize these impacts on the environment and bee populations, the use of biological control agents has been intensified. These products are generally safer for non-target insects, such as bees, which are important pollinating insects. Thus, the objective of this study was to evaluate the impact of entomopathogenic nematodes on the longevity of the Africanized honey bee A. mellifera workers. Seven treatments were used: Heterorhabditis amazonensis, Heterorhabditis bacteriophora, Heterorhabditis indica, Steinernema carpocapsae, Steinernema feltiae, and Steinernema rarum, at a concentration of 40 infective juveniles per cm² (IJs/cm²), and a control in which autoclaved distilled water was used. Two bioassays were performed: 1) spraying nematodes on the workers and 2) spraying nematodes on glass plates, in which the bees remained for two hours. Each treatment consisted of five replicates with 20 bees each. Bees were kept in cages of PVC (20 × 10 cm) covered with a voile fabric and provided pieces of cotton soaked in water and Candy paste. The cages were kept in a climatized room (27 ± 2 °C temperature, 60 ± 10% relative humidity, and 12 h photophase) and the mortality was evaluated from 12 to 240 hours. In bioassay 1, the three treatments with nematodes of the genus Steinernema reduced the longevity of the workers (103.9, 96.3, and 99.6 h) when compared to treatments with Heterorhabditis (149.7, 126.8, and 134.7 h), of which, only H. amazonensis (149.7 h) did not differ from the control (166.0 h). In bioassay 2, all treatments reduced the longevity of honey bees (155.4 to [...].(AU)

As populações de abelhas africanizadas (Apis mellifera L.) vêm diminuindo devido, principalmente, ao intenso uso de inseticidas sintéticos. Desde modo, o emprego de agentes de controle biológico tem-se intensificado de forma a minimizar este impacto no ambiente. Estes produtos são, de modo geral, mais seguros aos insetos não-alvos, como as abelhas que são importantes insetos polinizadores. Desta forma, o objetivo deste trabalho foi avaliar os efeitos de nematoides entomopatogênicos utilizados para controle de insetos pragas, sobre a longevidade de operárias de A. mellifera africanizada. Foram utilizados sete tratamentos: Heterorhabditis amazonensis, Heterorhabditis bacteriophora, Heterorhabditis indica, Steinernema carpocapsae, Steinernema feltiae e Steinernema rarum, na concentração de 40 juvenis infectantes por cm² (JIs/cm²), e como testemunha água destilada autoclavada. Para isso foram realizados dois bioensaios: 1) Pulverização dos nematoides sobre as operárias e 2) Pulverização dos nematoides em placas de vidro, nas quais as abelhas permaneceram por duas horas em contato. Cada tratamento foi composto por cinco repetições com 20 abelhas cada. As abelhas foram mantidas em gaiolas de PVC (20x10cm) cobertas com tecido voile e fornecidos pedaços de algodão embebido em água e pasta Candy. As gaiolas foram mantidas em sala climatizada (27 ± 2 °C, U.R. 60 ± 10%, fotofase de 12h) e a mortalidade avaliada de 12 até 240 horas. No bioensaio 1 os três tratamentos com nematoides do gênero Steinernema reduziram a longevidade das operárias (103,9; 96,3 e 99,6 horas) quando comparados aos tratamentos com Heterorhabditis (149,7; 126,8 e 134,7 horas). Entretanto, dentre estes apenas H. amazonensis (149,7 horas) não diferiu da testemunha (166,0 horas). No bioensaio 2, todos os [...].(AU)

Assuntos

RESUMO

The aim of this study was to assess the effects of three strains of Bacillus thuringiensis (Bt) on the longevity of workers of Africanized honey bee. Solutions at a concentration of 3 × 108 spores.mL-1 (dosage) were prepared for each strain of Bt (IPS 82, BR 81, and BR 147). Three bioassays were performed as follows: spraying on the bees, contact with the sprayed surface, and candy paste incorporated with Bt. The bees of the Bt bioassay were submitted to histological analysis of the mesenteron. The longevity of workers was assessed from one to 120 hours using different ranges. It was found that the bees that were exposed to the strain of Bt IPS 82, in the spraying test, exhibited a reduced longevity. In the contact test, the BR 147 strain reduced the longevity of the bees. In the food test, in turn, the three studied strains reduced the longevity of the bees as follows: Bt IPS 82: 64.5 hours; Bt BR 81: 64.5 hours; and Bt BR 147: 60.0 hours. The Bt BR 81 strain was considered the most selective of the evaluated strains on Apis mellifera, reducing the longevity of this bee only when it came into contact by the method of ingestion.

O objetivo deste trabalho foi avaliar o efeito de três linhagens de Bacillus thuringiensis (Bt) sobre a longevidade de operárias de Apis mellifera africanizadas. Para isso foram preparadas soluções, na concentração de 3x108 esporos/mL-1 (dosagem comercial), para cada linhagem de Bt (IPS 82, BR 81 e BR 147). Foram realizados três bioensaios: pulverização sobre as abelhas, contato com superfície pulverizada e pasta Cândi incorporada com Bt. As abelhas do bioensaio de Bt incorporado à alimentação foram submetidos à análise histológica do mesêntero. A longevidade das operárias foi avaliada de uma até 120 horas utilizando diferentes intervalos. Verificou-se que no teste de pulverização, as abelhas que entraram em contato com a linhagem de Bt IPS 82 apresentaram redução de longevidade. No teste de contato, a linhagem BR 147 reduziu a longevidade das abelhas. No teste de alimentação as três linhagens estudadas reduziram a longevidade das abelhas Bt IPS 82: 64,5 horas; Bt BR 81: 64,5 horas e Bt BR 147: 60,0 horas. A linhagen Bt BR 81 foi considerada a mais seletiva, dentre as avaliadas, reduzindo a longevidade da abelha A. mellifera apenas quando ingerida.

Assuntos

RESUMO

The aim of this study was to assess the effects of three strains of Bacillus thuringiensis (Bt) on the longevity of workers of Africanized honey bee. Solutions at a concentration of 3 × 108 spores.mL-1 (dosage) were prepared for each strain of Bt (IPS 82, BR 81, and BR 147). Three bioassays were performed as follows: spraying on the bees, contact with the sprayed surface, and candy paste incorporated with Bt. The bees of the Bt bioassay were submitted to histological analysis of the mesenteron. The longevity of workers was assessed from one to 120 hours using different ranges. It was found that the bees that were exposed to the strain of Bt IPS 82, in the spraying test, exhibited a reduced longevity. In the contact test, the BR 147 strain reduced the longevity of the bees. In the food test, in turn, the three studied strains reduced the longevity of the bees as follows: Bt IPS 82: 64.5 hours; Bt BR 81: 64.5 hours; and Bt BR 147: 60.0 hours. The Bt BR 81 strain was considered the most selective of the evaluated strains on Apis mellifera, reducing the longevity of this bee only when it came into contact by the method of ingestion.(AU)

O objetivo deste trabalho foi avaliar o efeito de três linhagens de Bacillus thuringiensis (Bt) sobre a longevidade de operárias de Apis mellifera africanizadas. Para isso foram preparadas soluções, na concentração de 3x108 esporos/mL-1 (dosagem comercial), para cada linhagem de Bt (IPS 82, BR 81 e BR 147). Foram realizados três bioensaios: pulverização sobre as abelhas, contato com superfície pulverizada e pasta Cândi incorporada com Bt. As abelhas do bioensaio de Bt incorporado à alimentação foram submetidos à análise histológica do mesêntero. A longevidade das operárias foi avaliada de uma até 120 horas utilizando diferentes intervalos. Verificou-se que no teste de pulverização, as abelhas que entraram em contato com a linhagem de Bt IPS 82 apresentaram redução de longevidade. No teste de contato, a linhagem BR 147 reduziu a longevidade das abelhas. No teste de alimentação as três linhagens estudadas reduziram a longevidade das abelhas Bt IPS 82: 64,5 horas; Bt BR 81: 64,5 horas e Bt BR 147: 60,0 horas. A linhagen Bt BR 81 foi considerada a mais seletiva, dentre as avaliadas, reduzindo a longevidade da abelha A. mellifera apenas quando ingerida.(AU)

Assuntos

RESUMO

Very little effort has been made to investigate bee population dynamics among intact wilderness areas. The presence of newly-arrived feral Africanized honey bee (AHB), Apis mellifera (Apidae), populations was studied for 10-17 years in areas previously with few or no escaped European apiary honey bees. Here I describe and interpret the major results from studies in three neotropical forests: French Guiana, Panama and Yucatan, Mexico (5° to 19° N. latitude). The exotic Africanized honey bees did not produce a negative effect on native bees, including species that were solitary or highly eusocial. Major differences over time were found in honey bee abundance on flowers near habitat experiencing the greatest degree of disturbance, compared to deep forest areas. At the population level, sampled at nest blocks, or at flower patches, or at light traps, there was no sudden decline in bees after AHB arrival, and relatively steady or sinusoidal population dynamics. However, the native bees shifted their foraging time or floral species. A principal conclusion is that such competition is silent, in floristically rich habitats, because bees compensate behaviorally for competition. Other factors limit their populations.

Pocos estudios han considerado la dinámica de poblaciones de abejas en bosques o hábitats no alterados por el hombre. La presencia de abejas silvestres Africanizadas de Apis mellifera (Apidae) fue estudiado por 10-17 años en áreas previamente sin esta especie. Aquí presento e interpreto resultados de tres bosques neotropicales: Guyana Francesa, Panamá y Yucatán, México (5° a 19° N. latitud). La abeja Africanizada exótica no produjo efecto negativo en las abejas nativas, incluyendo especies altamente sociales y solitarias. Diferencias mayores a través del tiempo fueron encontradas en la abundancia de las abejas de miel en flores cerca de hábitat con mayor grado de disturbio, comparado con el bosque espeso. Al nivel poblacional, muestreado en bloques de nidos trampa, en flores o con trampas ultravioletas de insectos, no hubo disminución pronta de abejas, y sí hubo una población relativamente estable o sinusoidal. Sin embargo, las abejas nativas cambiaron su hora de buscar provisiones o su selección de especies florales. Una conclusión principal es que esta competencia por los recursos es ‘silenciosa';, en las áreas florísticamente ricas estudiadas, porque las mismas abejas compensan con su comportamiento. Otros factores rigen sus poblaciones.

RESUMO

O objetivo deste trabalho foi avaliar a toxicidade de inseticidas/acaricidas utilizados em cultura de citros para operárias africanizadas de Apis mellifera Linnaeus. A exposição das abelhas aos compostos foi realizada usando-se técnicas de pulverização, contaminação da dieta e contato em superfícies tratadas (folhas de citros e placas de Petri), empregando-se asdoses máximas recomendadas para a cultura. Os bioensaios foram realizados em laboratório a 25±2°C, UR 70±10% efotofase de 12h, sendo os dados de mortalidade submetidos à análise estatística, e as médias comparadas por contraste, obtendo-se grupos de efeitos semelhantes. Independente do modo de exposição, o acefato foi extremamente tóxico, matando mais de 90,0% das abelhas 24h após a aplicação. Os produtos espirodiclofeno e piriproxifem, quando aplicados diretamente sobre as abelhas, causaram níveis de mortalidade de 11,0 e 15,0%, respectivamente; os compostos buprofezina, enxofre e tetradifona apresentaram níveis de mortalidade ainda menores, com média de 5,0% entre eles. Para os ensaios decontaminação de superfície (folhas de citros e placas de Petri) e contaminação de alimento, foram obtidos dois grupos de toxicidade, um grupo somente com acefato e outro, com buprofezina, enxofre, espirodiclofeno, piriproxifem, tetradifona e água. A mortalidade média para esse segundo grupo, após 96h do início da exposição, foi de 31,0; 8,3 e 15,7%, respectivamente, para cada método de contaminação.

The aim of this research was to evaluate the toxicity of several acaricides/insecticides used in Brazilian citrus crop to africanized workers of Apis mellifera Linnaeus. The expositionof honey bees to the chemicals was performed by direct spraying, contamination of food, and contact in treated surface (citrus leaves and Petri dishes), using recommended rates ofapplication. The assays were carried out at 25±2°C, RH 70±10%, 12h of photophase and the data was statisticallyanalyzed, with mean values of mortality being compared through cluster analysis. In all assays acephate was highly toxic, with mortality at 24 hours around 90.0%. When spirodiclofen and pyriproxyfen, was sprayed directly into the honeybees, they caused mortality levels of 11.0 and 15.0%, respectively; buprofezin, sulphur and tetradifon were less toxic, with mean mortality of 5.0% among these compounds. For the assays from contamination surface (citrus leaves and Petri dishes) and food, two groups of chemicals with the same toxiceffects were observed, one with acephate and other with buprofezin, sulphur, spirodiclofen, pyriproxyfen, tetradifon and water. The average mortality after 96 hours of exposition was 31.0; 8.3 and 15.7%, respectively, for each method of contamination.

RESUMO

The aim of this research was to evaluate the toxicity of several acaricides/insecticides used in Brazilian citrus crop to africanized workers of Apis mellifera Linnaeus. The exposition of honey bees to the chemicals was performed by direct spraying, contamination of food, and contact in treated surface (citrus leaves and Petri dishes), using recommended rates of application. The assays were carried out at 25±2°C, RH 70±10%, 12h of photophase and the data was statistically analyzed, with mean values of mortality being compared through cluster analysis. In all assays acephate was highly toxic, with mortality at 24 hours around 90.0%. When spirodiclofen and pyriproxyfen, was sprayed directly into the honeybees, they caused mortality levels of 11.0 and 15.0%, respectively; buprofezin, sulphur and tetradifon were less toxic, with mean mortality of 5.0% among these compounds. For the assays from contamination surface (citrus leaves and Petri dishes) and food, two groups of chemicals with the same toxic effects were observed, one with acephate and other with buprofezin, sulphur, spirodiclofen, pyriproxyfen, tetradifon and water. The average mortality after 96 hours of exposition was 31.0; 8.3 and 15.7%, respectively, for each method of contamination.

O objetivo deste trabalho foi avaliar a toxicidade de inseticidas/acaricidas utilizados em cultura de citros para operárias africanizadas de Apis mellifera Linnaeus. A exposição das abelhas aos compostos foi realizada usando-se técnicas de pulverização, contaminação da dieta e contato em superfícies tratadas (folhas de citros e placas de Petri), empregando-se as doses máximas recomendadas para a cultura. Os bioensaios foram realizados em laboratório a 25±2°C, UR 70±10% e fotofase de 12h, sendo os dados de mortalidade submetidos à análise estatística, e as médias comparadas por contraste, obtendo-se grupos de efeitos semelhantes. Independente do modo de exposição, o acefato foi extremamente tóxico, matando mais de 90,0% das abelhas 24h após a aplicação. Os produtos espirodiclofeno e piriproxifem, quando aplicados diretamente sobre as abelhas, causaram níveis de mortalidade de 11,0 e 15,0%, respectivamente; os compostos buprofezina, enxofre e tetradifona apresentaram níveis de mortalidade ainda menores, com média de 5,0% entre eles. Para os ensaios de contaminação de superfície (folhas de citros e placas de Petri) e contaminação de alimento, foram obtidos dois grupos de toxicidade, um grupo somente com acefato e outro, com buprofezina, enxofre, espirodiclofeno, piriproxifem, tetradifona e água. A mortalidade média para esse segundo grupo, após 96h do início da exposição, foi de 31,0; 8,3 e 15,7%, respectivamente, para cada método de contaminação.

RESUMO

The aim of this research was to evaluate the toxicity of several acaricides/insecticides used in Brazilian citrus crop to africanized workers of Apis mellifera Linnaeus. The exposition of honey bees to the chemicals was performed by direct spraying, contamination of food, and contact in treated surface (citrus leaves and Petri dishes), using recommended rates of application. The assays were carried out at 25±2°C, RH 70±10%, 12h of photophase and the data was statistically analyzed, with mean values of mortality being compared through cluster analysis. In all assays acephate was highly toxic, with mortality at 24 hours around 90.0%. When spirodiclofen and pyriproxyfen, was sprayed directly into the honeybees, they caused mortality levels of 11.0 and 15.0%, respectively; buprofezin, sulphur and tetradifon were less toxic, with mean mortality of 5.0% among these compounds. For the assays from contamination surface (citrus leaves and Petri dishes) and food, two groups of chemicals with the same toxic effects were observed, one with acephate and other with buprofezin, sulphur, spirodiclofen, pyriproxyfen, tetradifon and water. The average mortality after 96 hours of exposition was 31.0; 8.3 and 15.7%, respectively, for each method of contamination.

O objetivo deste trabalho foi avaliar a toxicidade de inseticidas/acaricidas utilizados em cultura de citros para operárias africanizadas de Apis mellifera Linnaeus. A exposição das abelhas aos compostos foi realizada usando-se técnicas de pulverização, contaminação da dieta e contato em superfícies tratadas (folhas de citros e placas de Petri), empregando-se as doses máximas recomendadas para a cultura. Os bioensaios foram realizados em laboratório a 25±2°C, UR 70±10% e fotofase de 12h, sendo os dados de mortalidade submetidos à análise estatística, e as médias comparadas por contraste, obtendo-se grupos de efeitos semelhantes. Independente do modo de exposição, o acefato foi extremamente tóxico, matando mais de 90,0% das abelhas 24h após a aplicação. Os produtos espirodiclofeno e piriproxifem, quando aplicados diretamente sobre as abelhas, causaram níveis de mortalidade de 11,0 e 15,0%, respectivamente; os compostos buprofezina, enxofre e tetradifona apresentaram níveis de mortalidade ainda menores, com média de 5,0% entre eles. Para os ensaios de contaminação de superfície (folhas de citros e placas de Petri) e contaminação de alimento, foram obtidos dois grupos de toxicidade, um grupo somente com acefato e outro, com buprofezina, enxofre, espirodiclofeno, piriproxifem, tetradifona e água. A mortalidade média para esse segundo grupo, após 96h do início da exposição, foi de 31,0; 8,3 e 15,7%, respectivamente, para cada método de contaminação.

RESUMO

The aim of this research was to evaluate the toxicity of several acaricides/insecticides used in Brazilian citrus crop to africanized workers of Apis mellifera Linnaeus. The exposition of honey bees to the chemicals was performed by direct spraying, contamination of food, and contact in treated surface (citrus leaves and Petri dishes), using recommended rates of application. The assays were carried out at 25±2°C, RH 70±10%, 12h of photophase and the data was statistically analyzed, with mean values of mortality being compared through cluster analysis. In all assays acephate was highly toxic, with mortality at 24 hours around 90.0%. When spirodiclofen and pyriproxyfen, was sprayed directly into the honeybees, they caused mortality levels of 11.0 and 15.0%, respectively; buprofezin, sulphur and tetradifon were less toxic, with mean mortality of 5.0% among these compounds. For the assays from contamination surface (citrus leaves and Petri dishes) and food, two groups of chemicals with the same toxic effects were observed, one with acephate and other with buprofezin, sulphur, spirodiclofen, pyriproxyfen, tetradifon and water. The average mortality after 96 hours of exposition was 31.0; 8.3 and 15.7%, respectively, for each method of contamination.

O objetivo deste trabalho foi avaliar a toxicidade de inseticidas/acaricidas utilizados em cultura de citros para operárias africanizadas de Apis mellifera Linnaeus. A exposição das abelhas aos compostos foi realizada usando-se técnicas de pulverização, contaminação da dieta e contato em superfícies tratadas (folhas de citros e placas de Petri), empregando-se as doses máximas recomendadas para a cultura. Os bioensaios foram realizados em laboratório a 25±2°C, UR 70±10% e fotofase de 12h, sendo os dados de mortalidade submetidos à análise estatística, e as médias comparadas por contraste, obtendo-se grupos de efeitos semelhantes. Independente do modo de exposição, o acefato foi extremamente tóxico, matando mais de 90,0% das abelhas 24h após a aplicação. Os produtos espirodiclofeno e piriproxifem, quando aplicados diretamente sobre as abelhas, causaram níveis de mortalidade de 11,0 e 15,0%, respectivamente; os compostos buprofezina, enxofre e tetradifona apresentaram níveis de mortalidade ainda menores, com média de 5,0% entre eles. Para os ensaios de contaminação de superfície (folhas de citros e placas de Petri) e contaminação de alimento, foram obtidos dois grupos de toxicidade, um grupo somente com acefato e outro, com buprofezina, enxofre, espirodiclofeno, piriproxifem, tetradifona e água. A mortalidade média para esse segundo grupo, após 96h do início da exposição, foi de 31,0; 8,3 e 15,7%, respectivamente, para cada método de contaminação.

RESUMO

A key to understanding the expansion of Africanized honey bees (Apis mellifera) is distinguishing this aggressive form from its European relative. Current identification techniques have a degree of success, but each has its own set of problems, prohibiting wide-spread adoption and use. This study examined aspects of central excitatory state, persistence of mobile appendages, and a viable sting after decapitation for their use in distinguishing between these two races. Central excitatory state was not useful in distinguishing the Africanized honey bee from the European honey bee; however, appendage mobility and sting viability were significantly different between the two subspecies. Appendage mobility and sting viability are useful techniques for distinguishing the two subspecies, and alleviate the issues of expense, application, and accuracy.(AU)

Uma chave para o entendimento da expansão da abelha africanizada (Apis mellifera) é distinguir esta abelha agressiva de sua equivalente européia. Técnicas de identificação atual têm um grau de sucesso, mas cada método tem seu próprio conjunto de problemas, tornando-se proibitivo sua adoção e uso em larga escala. Este estudo examinou aspectos do estado excitatório central, persistência de mobilidade de apêndices e viabilidade da ferroada após decapitação como ferramenta na distinção entre essas duas raças. O estado excitatório central não foi útil na distinção entre a abelha africanizada e a européia; todavia, a mobilidade de apêndices e a viabilidade do ferrão foram significativamente diferentes entre essas duas raças. A mobilidade de apêndices e a viabilidade do ferrão são técnicas úteis na distinção das duas raças e atenua os aspectos relacionados a gastos, aplicação e precisão.(AU)

Assuntos

RESUMO

Sunflower plants, cv Anhandy, freely visited by insects (control) were compared to plants protected from insects. Two flower isolation methods were used: covering the plants with net cages (width 3m, lenght 4m, height 2m) and bagging the flowers with gauze. The number, the weight and the percentage of seed setting were significantly higher (P 0.05) in the visited plants (579.28; 41.17g and 82.37%; 456.97; 23.44g 79.70%, in two trials) than in plants protected by cages (81.53; 2.23g and 1.16% in the first trial and 111.92; 3.16g e 28.49%, in the second). The number and the weight of no seed settings were significantly higher (P 0.05) in the plants covered with cages (416.29 and 6.58g; 375.25 and 5.04g in two trials) than in the control (142.69 and 1.71g; 182.38 and 2.53g). The percentage of seed setting in the bagged flowers with gauze was intermediate to the control plants and the covered plants. (64.56% in the first trial and 68.61%, in the second). It is concluded that the sunflower, cv Anhandy, presents a significant increase of seed production due to visits of pollinating insects, mainly honey bees. Cage is the most indicated method to protect plants from pollinating insects.

Foram realizados dois ensaios nos quais compararam-se plantas de girassol, do cultivar Anhandy, livremente visitadas por insetos(testemunhas) e outras impedidas de visitação por dois métodos (cobertura de plantas com gaiolas teladas, de 3m de largura, 4m de comprimento e 2m de altura, e ensacamento de capítulos com filó). O número, o peso e a porcentagem de sementes granadas foram significativamente maiores (P 0,05) nas plantas visitadas (579,28; 41,17g e 82,37%; 456,97; 23,44g 79,70%, nos dois ensaios), em relação às plantas cobertas com gaiolas teladas (81,53; 2,23g e 1,16% no primeiro ensaio e 111,92; 3,16g e 28,49%, no segundo). O número e o peso de sementes não granadas foram significativamente maiores (P 0,05) nas plantas cobertas com gaiolas teladas (416,29 e 6,58g; 375,25 e 5,04g, nos dois ensaios) em relação à testemunha (142,69 e 1,71g; 182,38 e 2,53g). Os capítulos ensacados com filó apresentaram valores de porcentagem de sementes granadas intermediários entre as plantas testemunhas e as cobertas com gaiolas teladas (64,56 no primeiro ensaio e 68,61, no segundo). Pode-se concluir que o cultivar de girassol em estudo apresenta significativo aumento de produção de sementes devido a visitas de insetos polinizadores, principalmente abelhas, e que as gaiolas teladas são mais indicadas como método para impedir o acesso de insetos polinizadores.

RESUMO

With the objective to know if there is influence of the material from which are made the cups used in the production of royal jelly, and if there isinterference of the plastic cup color on the acceptance rate of the larvae and royal jelly productivity, commercial cups of three different colors were checked and compared to 9 mm diameter wax cups. Six hives were provided with two cell bars contantining 2- cups each, totaling 40 cups per hive. Larva aged 24 - 48 hours were transferred to the cups over a drop of royaljelly diluted in water (50%). The cell builders were fed with sugar syrup and proteinic food composed of caw milk, Maritene, water and honey. To royal jelly produced was harvested 69 - 72 hours after the transference for the material from which were made the cups (plastic and wax) and 3 treatments foor the plastic cup colors (orange, yellow and white). The average regarding the percentile of larvae acceptance and the average per cell builder and per cup were compared by the Tukey"s procedure at 5% probability level. The results showed that differences did not occur in the average of larvae acceptance, nor in the quantity of royal produced per cell builder or per cup.

Com o objetivo de conhecer se existe influência do material com o qual são confeccionadas as cúpulas usadas para produção de geleia real, bem como, se existe interferência da cor das cúpulas plásticas sobre a aceitação das larvas e produção de geleia real, foram testadas cúpulas normalmente encontradas no comércio, de três diferentes cores, comparadas às cúpulas de 9 mm de diâmetro confeccionadas em cera. Foram introduzidas duas barras de 20 cúpulas cada uma por colmeia, totalizando 40, sendo transferidas larvas de 24 a 48 horas de idade, sobre uma gota de geleia real diluída em água, na proporção de 50%. As recrias foram alimentadas com xarope de açúcar e alimento proteíco composto de leite, Meritene, água e mel. A geleia real produzida foi colhida 69 a 72 horas após a transferência das larvas. O delineamento experimental utilixado foi o inteiramente ao acaso, com 2 tratamentos para material com o qual foram confeccionadas as cúpulas (plástico e cera) e com 3 tratamentos para cores das cúpulas plásticas (laranja, amarelo e branco). As médias referentes à porcentagem de aceitação das larvas e à produção por recria e por cúpulas foram comparadas pelo teste de Tukey ao nível de 5% de probabilidade. Os resultados obtidos mostram que não ocorreram diferenças (p > 0,05) nas médias de aceitação das larvas, nem na quantidade de geleia real produzida por recria, ou cúpula.

RESUMO

Sunflower plants, cv Anhandy, freely visited by insects (control) were compared to plants protected from insects. Two flower isolation methods were used: covering the plants with net cages (width 3m, lenght 4m, height 2m) and bagging the flowers with gauze. The number, the weight and the percentage of seed setting were significantly higher (P 0.05) in the visited plants (579.28; 41.17g and 82.37%; 456.97; 23.44g 79.70%, in two trials) than in plants protected by cages (81.53; 2.23g and 1.16% in the first trial and 111.92; 3.16g e 28.49%, in the second). The number and the weight of no seed settings were significantly higher (P 0.05) in the plants covered with cages (416.29 and 6.58g; 375.25 and 5.04g in two trials) than in the control (142.69 and 1.71g; 182.38 and 2.53g). The percentage of seed setting in the bagged flowers with gauze was intermediate to the control plants and the covered plants. (64.56% in the first trial and 68.61%, in the second). It is concluded that the sunflower, cv Anhandy, presents a significant increase of seed production due to visits of pollinating insects, mainly honey bees. Cage is the most indicated method to protect plants from pollinating insects.

Foram realizados dois ensaios nos quais compararam-se plantas de girassol, do cultivar Anhandy, livremente visitadas por insetos(testemunhas) e outras impedidas de visitação por dois métodos (cobertura de plantas com gaiolas teladas, de 3m de largura, 4m de comprimento e 2m de altura, e ensacamento de capítulos com filó). O número, o peso e a porcentagem de sementes granadas foram significativamente maiores (P 0,05) nas plantas visitadas (579,28; 41,17g e 82,37%; 456,97; 23,44g 79,70%, nos dois ensaios), em relação às plantas cobertas com gaiolas teladas (81,53; 2,23g e 1,16% no primeiro ensaio e 111,92; 3,16g e 28,49%, no segundo). O número e o peso de sementes não granadas foram significativamente maiores (P 0,05) nas plantas cobertas com gaiolas teladas (416,29 e 6,58g; 375,25 e 5,04g, nos dois ensaios) em relação à testemunha (142,69 e 1,71g; 182,38 e 2,53g). Os capítulos ensacados com filó apresentaram valores de porcentagem de sementes granadas intermediários entre as plantas testemunhas e as cobertas com gaiolas teladas (64,56 no primeiro ensaio e 68,61, no segundo). Pode-se concluir que o cultivar de girassol em estudo apresenta significativo aumento de produção de sementes devido a visitas de insetos polinizadores, principalmente abelhas, e que as gaiolas teladas são mais indicadas como método para impedir o acesso de insetos polinizadores.

RESUMO

With the objective to know if there is influence of the material from which are made the cups used in the production of royal jelly, and if there isinterference of the plastic cup color on the acceptance rate of the larvae and royal jelly productivity, commercial cups of three different colors were checked and compared to 9 mm diameter wax cups. Six hives were provided with two cell bars contantining 2- cups each, totaling 40 cups per hive. Larva aged 24 - 48 hours were transferred to the cups over a drop of royaljelly diluted in water (50%). The cell builders were fed with sugar syrup and proteinic food composed of caw milk, Maritene, water and honey. To royal jelly produced was harvested 69 - 72 hours after the transference for the material from which were made the cups (plastic and wax) and 3 treatments foor the plastic cup colors (orange, yellow and white). The average regarding the percentile of larvae acceptance and the average per cell builder and per cup were compared by the Tukey"s procedure at 5% probability level. The results showed that differences did not occur in the average of larvae acceptance, nor in the quantity of royal produced per cell builder or per cup.

Com o objetivo de conhecer se existe influência do material com o qual são confeccionadas as cúpulas usadas para produção de geleia real, bem como, se existe interferência da cor das cúpulas plásticas sobre a aceitação das larvas e produção de geleia real, foram testadas cúpulas normalmente encontradas no comércio, de três diferentes cores, comparadas às cúpulas de 9 mm de diâmetro confeccionadas em cera. Foram introduzidas duas barras de 20 cúpulas cada uma por colmeia, totalizando 40, sendo transferidas larvas de 24 a 48 horas de idade, sobre uma gota de geleia real diluída em água, na proporção de 50%. As recrias foram alimentadas com xarope de açúcar e alimento proteíco composto de leite, Meritene, água e mel. A geleia real produzida foi colhida 69 a 72 horas após a transferência das larvas. O delineamento experimental utilixado foi o inteiramente ao acaso, com 2 tratamentos para material com o qual foram confeccionadas as cúpulas (plástico e cera) e com 3 tratamentos para cores das cúpulas plásticas (laranja, amarelo e branco). As médias referentes à porcentagem de aceitação das larvas e à produção por recria e por cúpulas foram comparadas pelo teste de Tukey ao nível de 5% de probabilidade. Os resultados obtidos mostram que não ocorreram diferenças (p > 0,05) nas médias de aceitação das larvas, nem na quantidade de geleia real produzida por recria, ou cúpula.