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The "River Disease" (RD), a disorder impacting honeybee colonies located close to waterways with abundant riparian vegetation (including Sebastiania schottiana, Euphorbiaceae), kills newly hatched larvae. Forager bees from RD-affected colonies collect honeydew excretions from Epormenis cestri (Hemiptera: Flatidae), a planthopper feeding on trees of S. schottiana. First-instar honeybee larvae fed with this honeydew died. Thus, we postulated that the nectars of RD-affected colonies had a natural toxin coming from either E. cestri or S. schottiana. An untargeted metabolomics characterization of fresh nectars extracts from colonies with and without RD allowed to pinpoint xanthoxylin as one of the chemicals present in higher amounts in nectar from RD-affected colonies than in nectars from healthy colonies. Besides, xanthoxylin was also found in the aerial parts of S. schottiana and the honeydew excreted by E. cestri feeding on this tree. A larva feeding assay where xanthoxylin-enriched diets were offered to 1st instar larvae showed that larvae died in the same proportion as larvae did when offered enriched diets with nectars from RD-colonies. These findings demonstrate that a xenobiotic can mimic the RD syndrome in honeybee larvae and provide evidence of an interspecific flow of xanthoxylin among three trophic levels. Further, our results give information that can be considered when implementing measures to control this honeybee disease.

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Studies of insect feeding behavior are useful in different areas of entomology such as plant resistance, biology, and insecticide efficacy. For chewing insects, this kind of technique is well established, but for sap-sucking insects, especially tiny ones such as whiteflies, aphids, and psyllids, these tests can be laborious. Manipulation is difficult and can damage the plant, affecting the results. We describe here three types of cages for tests with small insects, one for seedlings in pots, a second for larger plants or plants in the field, and a third for caging insects on part of a leaf. These cages have been useful for different types of studies in addition to feeding behavior and can facilitate research with small phytophagous sucking insects.

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This study aimed to differentiate bracatinga (Mimosa scabrella Bentham) honeydew honey (BHH) from blossom honeys and BHH intentionally adulterated, all of them from three harvests, associating data of aliphatic organic acids (AOA) determined by capillary electrophoresis and chemometric analyses. The profile and concentration of AOA in pure BHH were similar between harvests, but distinct from blossom honeys. Succinic, glycolic, glutaric, malic, acetic, gluconic, and lactic acids were responsible for the differentiation between these two types of honey since they were the dominant variables (r > 0.80) in the principal component analysis. Based on this, the classification and regression trees method was used to develop a classification model considering these AOA. The proposed method needed only six of these AOA and adequately classified all blossom honeys and almost all pure and adulterated BHH. Therefore, the proposed model proved to be promising and reliable for verifying authenticity and fraud detection in BHH.

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ABSTRACT Scale insects Stigmacoccus paranaensis (Foldi, 2006) associated with bracatinga trees (Mimosa scabrella) in Santa Catarina, Brazil, can play an important economic role and guarantee the production of "bracatinga honeydew honey". This scale insect has the ability to excrete large amounts of honeydew, of economic importance for beekeepers, especially due to the natural occurrence of host plants at high density, known as "bracatingais". In this sense, the objective of this study was to evaluate the honeydew produced by scale insects associated with M. scabrella in the Bom Retiro, Santa Catarina, Brazil. We determined the density of the host plant in the studied area, the intensity of infestation by scale insects, and the volume and sugar concentration of excreted honeydew. The average density of bracatinga was 437.5 individuals ha-1, and the average density of scale insects per plant was 8,287. During 10 minutes, the average rate of honeydew excretion by scale insects was 0.45 µl and 0.34 µl, respectively, in 2002 and 2004. The estimated volume of honeydew production was 0.54 L in 2002 and 0.41 L in 2004 tree-1 day-1. The highest sugar concentration was observed in 2004 (28.13%). The excretion rate was affected by climatological factors and the size of the insects. This is the first study presenting a systematic evaluation of honeydew production by scale insects in Southern Brazil. The results of the present study support production of honeydew honey in the Serra Catarinense region as an important sustainable economic and traditional activity.

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The main sources of food for stingless bees are the nectar and pollen harvested from flowers, whereas one important kind of nesting material (i.e. wax) is produced by their own abdominal glands. Stingless bees can, nonetheless, obtain alternative resources of food and wax from exudates released by sap-sucking insects as honeydew and waxy cover, respectively. To date, there are no comprehensive studies investigating how diversified and structured the network interactions between stingless bees and sap-sucking insects are. Here, we conducted a survey of the data on relationship between stingless bees and sap-sucking insects to evaluate: (1) which resources are collected by which stingless bee species; (2) how diverse the interaction network is, using species degree and specialisation index as a proxy; and if (3) there would be any phylogenetic signal in the species degree and specialisation indices. Our findings demonstrate that approximately 21 stingless bee species like Trigona spp. and Oxytrigona spp. have been observed interacting with 11 sap-sucking species, among which Aethalion reticulatum is the main partner. From ca. 50 records, Brazil is the country with most observations (n = 38) of this type of ecological interaction. We found also that stingless bees harvest fivefold more honeydew than waxy covers on sap-sucking insects. However, we did not find any phylogenetic signal for the occurrence of this interaction, considering species degree and specialisation indices, suggesting that both traits apparently evolved independently among stingless bee species. We suggest that specific ecological demands may drive this opportunistic behaviour exhibited by stingless bees, because major sources of food are obtained from flowers and these bees produce their own wax.

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Honeydew honeys have been under-evaluated about their major phenolic compounds, especially Mimosa scabrella Bentham (bracatinga) honeydew honey. In this work, a fast and robust chromatographic method was optimized for simultaneous separation and quantification by HPLC/DAD of 18 phenolic compounds detected in bracatinga honeydew honey. A simplex-centroid design, central composite rotatable design and response surface-desirability function simultaneous optimization of Derringer and Suich were used, evaluating the mobile phase composition, flow rate and oven temperature to separate all the peaks. These multivariate procedures were efficient in determining the optimal separation conditions, using peak pair resolutions and run time as responses. The 18 peaks were separated in 25 min and the mobile phase gradient started with 1.6% MeOH, 3.3% ACN, 1.0% THF and 94.1% formic acid 0.1% changing to 10.0% MeOH, 33.3% ACN, 6.0% THF and 50.7% formic acid 0.1%, oven temperature of 33 °C and flow rate of 0.73 mL min-1. The method was validated according to Eurachem guidelines and considered accurate and robust. It was applied to 18 bracatinga honeydew honey samples in which 9 phenolic compounds were identified and quantified.

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BACKGROUND: Due to the increasing valuation and appreciation of honeydew honey in many European countries and also to existing contamination among different types of honeys, authentication is an important aspect of quality control with regard to guaranteeing the origin in terms of source (honeydew or floral) and needs to be determined. Furthermore, proteins are minor components of the honey, despite the importance of their physiological effects, and can differ according to the source of the honey. In this context, the aims of this study were to carry out protein extraction from honeydew and floral honeys and to discriminate these honeys from the same botanical species, Mimosa scabrella Bentham, through proteome comparison using two-dimensional gel electrophoresis and principal component analysis. RESULTS: The results showed that the proteome profile and principal component analysis can be a useful tool for discrimination between these types of honey using matched proteins (45 matched spots). Also, the proteome profile showed 160 protein spots in honeydew honey and 84 spots in the floral honey. CONCLUSION: The protein profile can be a differential characteristic of this type of honey, in view of the importance of proteins as bioactive compounds in honey. © 2017 Society of Chemical Industry.

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A simple, reproducible and sensitive method has been optimized and validated for simultaneous determination of 32 phenolic compounds in bracatinga (Mimosa scabrella Benth.) with the diluted-and-shoot approach, without the need of any additional clean-up steps. It has been based on high performance liquid chromatography coupled with triple quadrupole tandem mass spectrometry and electrospray ionization (HPLC-ESI-MS/MS). The chromatography conditions were optimized, and due to the selectivity provided by MRM monitoring, LC separation required only 9min. The developed method was validated on the basis of Eurachem and European Commission Decision 2002/657/EC guidelines. Mean recoveries ranged from 70.4 to 110%. Intra-day and inter-day precision with RSD (relative standard deviations) from 0.14 to 18.9% and 0.34 to 20.0%, respectively were achieved. Limits of detection (LOD) and quantification (LOQ) ranged from 0.03 to 3.20µgL-1 and 0.20-12.8µgL-1. Finally, the method was applied to samples and 20 phenolic compounds were quantified in all the samples analyzed, representing a contribution to the characterization and quantification of phenolic compounds from bracatinga (M. scabrella Bentham) honeydew honey.

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Triplaris americana is a plant that has been applied as ornamental specie and also as natural medicine. Adults and immature stages of Aethalion reticulatum were observed colonizing specimens of this plant in Sinop, MT, Brazil, which represent the first record of this leafhopper colonizing this specie.

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Ant foraging on foliage can substantially affect how phytophagous insects use host plants and represents a high predation risk for caterpillars, which are important folivores. Ant-plant-herbivore interactions are especially pervasive in cerrado savanna due to continuous ant visitation to liquid food sources on foliage (extrafloral nectaries, insect honeydew). While searching for liquid rewards on plants, aggressive ants frequently attack or kill insect herbivores, decreasing their numbers. Because ants vary in diet and aggressiveness, their effect on herbivores also varies. Additionally, the differential occurrence of ant attractants (plant and insect exudates) on foliage produces variable levels of ant foraging within local floras and among localities. Here, we investigate how variation of ant communities and of traits among host plant species (presence or absence of ant attractants) can change the effect of carnivores (predatory ants) on herbivore communities (caterpillars) in a cerrado savanna landscape. We sampled caterpillars and foliage-foraging ants in four cerrado localities (70-460 km apart). We found that: (i) caterpillar infestation was negatively related with ant visitation to plants; (ii) this relationship depended on local ant abundance and species composition, and on local preference by ants for plants with liquid attractants; (iii) this was not related to local plant richness or plant size; (iv) the relationship between the presence of ant attractants and caterpillar abundance varied among sites from negative to neutral; and (v) caterpillars feeding on plants with ant attractants are more resistant to ant predation than those feeding on plants lacking attractants. Liquid food on foliage mediates host plant quality for lepidopterans by promoting generalized ant-caterpillar antagonism. Our study in cerrado shows that the negative effects of generalist predatory ants on herbivores are detectable at a community level, affecting patterns of abundance and host plant use by lepidopterans. The magnitude of ant-induced effects on caterpillar occurrence across the cerrado landscape may depend on how ants use plants locally and how they respond to liquid food on plants at different habitats. This study enhances the relevance of plant-ant and ant-herbivore interactions in cerrado and highlights the importance of a tritrophic perspective in this ant-rich environment.

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Cryptoblabes gnidiella (Millière) (Lepidoptera: Pyralidae) has been known in Uruguay for 30 years and only in vineyards, despite being polyphagous. In recent years, this pest has caused sporadic but serious damage on some grapevine cultivars. Understanding the insect's phenology and developing a monitoring program are essential aspects of integrated pest management. We monitored males using sexual pheromone traps on four cultivars of vine, Pinot noir, Tannat, Gewürztraminer, and Cabernet Sauvignon, in two vine-growing establishments in the Department of Canelones and compiled data on the accumulated effective temperatures for the southern area of Uruguay. We determined that this species undergoes three generations per year and overwinters without diapause as larvae on dried grapes remaining after harvest. Using the proportion of cumulative male moths caught from December to May from 2003-2007 on the four cultivars and the sum of effective temperatures above two previously-published lower-threshold temperatures for development, 12.26°C and 13°C, statistically significant logistic models were estimated. Predictions based on the resulting models suggested that they would be acceptable tools to improve the efficiency of integrated management of this pest in Uruguay.

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Predatory syrphid larvae feed on relatively immobile prey, but here we report the first case (as far as we are aware) of obligatory predation on very mobile prey. Larvae of an undescribed species of Ocyptamus (Diptera: Syrphidae) were found in whitefly (Hemiptera: Aleyrodidae) aggregations on the undersides of citrus leaves. However, instead of preying on the whitefly nymphs (as would be expected), the larvae preyed on adult flies (Diptera) that were attracted to the honeydew. In the laboratory, larvae captured significantly more flies on whitefly infested leaves than on washed leaves, and generally abandoned leaves that lacked whiteflies. Most cases of successful prey capture involved flies that probed the anterior part of the larva’s body with its proboscis (as if it were honeydew). The syrphid larva lashed out at the fly and entangled it in sticky oral secretion. The prey did not recover when they were removed from the larva, suggesting that this new predatory species also employs venom to subdue its prey. Although the larvae consumed some honeydew, they were unable to complete their development on this diet. Two parasitoids were reared from Ocyptamus puparia, Proaspicera sp. (Hymenoptera: Figitidae) and Paracarotomus sp. (Hymenoptera: Pteromalidae), both of which are endoparasitic koinobionts. Rev. Biol. Trop. 58 (4): 1157-1163. Epub 2010 December 01.

Las larvas depredadoras de Syrphidae se alimentan de presas relativamente inmóviles, pero aquí reportamos el primer caso (hasta ahora conocido) de la depredación obligatoria en presas muy móviles. Se encontraron las larvas de una especie no descrita de Ocyptamus (Diptera: Syrphidae) juntas con ninfas de mosca blanca (Hemiptera: Aleyrodidae) en el envés de las hojas de cítricos. Sin embargo, en vez de alimentarse de las ninfas de mosca blanca (como debería esperarse), las larvas se alimentaron de moscas adultas (Diptera) que fueron atraídas a las excreciones azucaradas de la mosca blanca. En el laboratorio, las larvas capturaron más moscas cuando estaban en hojas con mosca blanca que cuando estaban en hojas lavadas, y generalmente abandonaron las hojas sin mosca blanca. La mayoría de las capturas exitosas de presas ocurrieron cuando la mosca extendió su proboscis y tocó la parte anterior de la larva del sírfido. La larva regurgita hilos pegajosos en el momento de capturar una presa y presas removidas de la larva no recuperaron su movibilidad, lo cual sugiere que el depredador utiliza un veneno para inmovilizar la presa. Aunque las larvas se alimentaron de excreciones azucaradas de mosca blanca, no pudieron completar su desarrollo en esta dieta. Se obtuvieron dos parasitoides de los puparios del sírfido, Proaspicera sp. (Hymenoptera: Figitidae) Paracarotomus sp. (Hymenoptera: Pteromalidae), ambos son koinobiontes endoparasíticos.

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La bioactividad de la miel de abejas ha sido aplicada en apiterapia tradicional y moderna. El origen botánico ocasiona variaciones en los principios activos y en el color de este producto, desde incoloro y blanquecino hasta marrón oscuro en la escala ámbar. Se evaluó la actividad antioxidante total (AAT) de 50 mieles enviadas al servicio de Análisis Químico del Instituto de Investigaciones Apícolas en Dol, República Checa, con el método del catión radical ABTS·+. Se encontraron las siguientes variaciones de AAT (µmoles equivalentes Trolox) para 22 mieles florales (60,12-287,55), 15 mieles de mielada (53,71-280,04) y 13 mieles mixtas (43,55-290,35). La AAT no varió significativamente según el origen botánico de las mieles, pero fue directamente proporcional al color y al contenido de flavonoides y de polifenoles. Se sugiere una clasificación de mieles según su contenido bajo, medio o alto de AAT.

The bioactivity of honey has been used in traditional and modern apitherapy. The botanical origin of honey causes variations in this product's active principles and color, from almost colorless whitish to dark brown in the amber scale. The total antioxidant activity (TAA) of 50 honeys sent to the service of Chemical Analysis of the Institute of Apicultural Investigations in Dol, Czech Republic, was evaluated by the method of the radical cation ABTS·+. The following variations of AAT (µmols Trolox equivalent) were found for 22 floral honeys (60.12-287.55), 15 honeydew honeys (53.71-280.04) and 13 mixed honeys (43.55-290.35). The TAA did not vary significantly according to the botanical origin but was directly proportional to color and content of flavonoids and polyphenols. A classification of honey according to its low, medium and high TAA is suggested.

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O objetivo deste estudo foi registrar e comparar a ocorrência de adultos e imaturos da traça-dos-cachos, Cryptoblabes gnidiella (Millière), em dois vinhedos, nos diferentes estágios fenológicos de Vitis vinifera cv. Pinot Noir, em Bento Gonçalves (29°10'S 51°32'O), RS, no período de 2004-2005. Quinzenalmente a população de imaturos foi monitorada em cachos e ramos de videira, enquanto os adultos, em armadilhas com feromônio sexual sintético. Houve diferença significativa entre o número de indivíduos coletados nos diferentes estágios fenológicos da videira. No período de cachos secos registrou-se o maior número de C. gnidiella. A permanência de cachos secos nos vinhedos após a colheita permite o refúgio dos imaturos de C. gnidiella no período de entressafra.

The aim of this study was to record and compare the occurrence of adults and immature stages of honeydew moth, Cryptoblabes gnidiella (Millière), related with grape phenology in two Pinot Noir (Vitis vinifera) vineyards in Bento Gonçalves (29°10'S 51°32'O), RS, during 2004-2005. Fortnightly, immature stages were monitored in the clusters and grapevine branches, while the adults, in delta traps baited with synthetic sex pheromone. There were significant differences in the number of individuals in different phenologic stages of vineyards. The highest catches of honeydew moth were registered in the period of dry clusters. The permanence of dry cluster after harvest, could serve as refuge for C. gnidiella immatures between seasons.

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ABSTRACT The honeydew moth, Cryptoblabes. gnidiella, is an important pest on grapevine orchards, in Bento Gonçalves, state of Rio Grande do Sul, Brazil. This study was aimed to verify the parasitism on immatures stages of C. gnidiella. Samples of grapes and branches in two orchards of Vitis vinifera, managed with and without insecticide treatment, were carried out from July/2004 to July/2005. Biweekly observations revealed, at most, 100 larvae and 100 pupae of C. gnidiella from each orchard area. The immature stages were kept in an acclimatized chamber (25 ± 1º C) until the emergence of adults or parasitoids. Five species of Hymenoptera were found associated with C. gnidiella: Apanteles sp. (Braconidae), Perilampidae, Pimpla croceiventris (Cresson) (Ichneumonidae), Venturia sp. (Ichneumonidae) and Macrocentrus sp. (Braconidae). Venturia sp. was the most abundant parasitoidin the two orchards. More species were observed in the orchard without application of insecticides.

RESUMO A traça-dos-cachos Cryptoblabes gnidiella tem se destacado como praga importante no cultivo da videira em Bento Gonçalves, RS, Brasil. Com o objetivo de verificar a incidência de parasitismo sobre as formas imaturas de C. gnidiella foram realizadas amostragens quinzenais de cachos e ramos em 2 pomares de Vitis vinifera, mantidos com e sem aplicação de inseticidas, no período de julho/2004 a julho/2005. O material coletado foi examinado em laboratório com auxílio de microscópio estereoscópio Wild M5 separando-se até 100 lagartas e 100 pupas de C. gnidiella de cada pomar por amostragem. Os imaturos foram mantidos em câmara climatizada com temperatura constante de 25º C até a emergência dos adultos da traça ou de parasitóides. Desse material registrou-se a emergência dos Hymenoptera Apanteles sp. (Braconidae), Perilampidae, Pimpla croceiventris (Cresson) (Ichneumonidae), Venturia sp. (Ichneumonidae) e Macrocentrus sp. (Braconidae). Venturia sp. foi o parasitóide mais abundante nos 2 pomares. Foi constatada uma maior riqueza de espécies no pomar sem aplicação de inseticidas.

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O mel de melato é produzido a partir de secreçöes de partes vivas das plantas difere do mel floral em vários aspectos. Foram analisadas 14 amostras de mel floral e 11 amostras de mel de melato provenientes de Minas Gerais e de Santa Catarina, assim classificadas de acordo com os métodos de Kirkood e de White. Foram realizadas as determinaçöes de pH, reaçäo de Lund, viscosidade e condutividade. Foi aplicado o teste exato de Fisher que demonstrou haver associaçäo entre mel de melato e pH acima de 4,2, reaçäo de Lund abaixo de 0,6 e viscosidade acima de 19,4. Foram analisadas misturas contendo diferentes proporçöes de mel de melato em mel floral e determinados valores para polarimetria, condutividade, pH, resíduo mineral fixo, açúcares redutores de viscosidade. Á medida que aumentou a concentraçäo do mel de melato houve uma alteraçäo significativa nos valores das variáveis analisadas, verificada pelo coeficiente de regressäo b. Foi demonstrado que algumas medidas como pH e viscosidade podem ser aplicadas como critério de diferenciaçäo entre estes dois tipos de mel. (AU)

Honeydew honey differs of the floral honey in many aspects. In order to check that eleven honeydew honey and fourteen floral honey were analysed for pH, Lund reaction, conductivity and viscosity. The Fisher test was applied to check if there was any association between the kind of honey and the quantitative aspects of this study. It was demonstrated that there is association between honeydew honey and the pH above 4,2, Lund reaction below 0,6 mL and viscosity above 19,4. In order to study the effects of a gradative addition of honeydew honey on floral honey and its characteristics such as polarimetry, conductivity, pH, ashes, reducing sugars and viscosity, a linear regression analysis of these characteristics, was done using a blend of both kind of honey. It was observed by the regression coefficient b that the floral honey mixed with honeydew honey showed a significative modification of variables studied when the concentration of honeydew honey was increased. (AU)

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Com a finalidade de verificar diferenças sensoriais entre mel floral e, identificar a presença do mel de melato misturado ao mel floral, foi aplicado o teste de diferença pareado e a determinaçäo instrumantal de cor e tubidez em várias amostras de mel. Foi tomada uma amostra de mel floral puro e uma amostra de mel de melato puro como referências. Foram elaboradas no laboratório misturas de mel floral com quantidades variadas de mel de melato para a aplicaçäo dos testes. Na caracterizaçäo sensorial foi observado que o mel floral apresentou aroma e sabor mais caracteristico, menor viscosidade e gosto doce mais acentuado que o mel de melato puro. Em relaçäo às misturas, nos testes definitivos, foi observado que, entre 10 e 15(por cento), a mistura começou a perder aroma e sabor característicos, ficou mais viscosa e mais doce. No entanto, ficou demonstrado que as amostras mostraram varibilidade sensorial. A medida de cor foi afetada pela presença de mel de melato. As medidas de turbidez e luminosidade näo mostraram resultados significativos. (AU)

The paired comparison test and the instrumental determination of colour and turbidity wereapplied to identify the presence of honeydew honey in various honey samples. The references used were apure floral honey and a pure honeydew honey. Mixtures containing both of them were made at the laboratoryto run the tests. The sensorial characterization showed the floral honey presented a more characteristicflavor, less viscosity and it was sweeter than honeydew honey. The definitive test indicated that between 10and 15% the mixture started to lose its characteristic flavor, became more viscous and sweeter than the floralhoney. In fact samples showed sensorial variability. The measure of colour was affected by the presence ofhoneydew honey. Turbidity and luminosity did not show significant results. (AU)

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