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Since 1890, many observations of danaine butterflies visiting dry plants of several families in the Old and New World tropics have been published. For 50 years, it has been recognised that Danainae, along with various other insects, seek out 1,2-dehydropyrrolizidine ester alkaloids (PAs) independently of and in addition to their nutritive requirements and utilise them to increase their chances for survival and biological fitness. This represents an unusual type of insect-plant relationship ("PA-pharmacophagy"), with remarkable peculiarities but also with gaps in knowledge, many of which can be filled by employing PA-baiting. We review and analyse the history of records on the attraction of adult insects to PAs and unveil the complex background information on PA-chemistry, PA-producing plants ("PA-plants"), and PA-sequestering insects ("PA-insects") in order to come up with practical tips for successful baiting with PAs ("PA-baiting"). Studying PA-pharmacophagy integrates taxonomy, behaviour, and ecology with evolutionary biology, chemistry, and toxicology. With basic knowledge of PA-chemistry and bearing the general peculiarities of PA-plants and PA-insects in mind, PA-baiting can be conducted easily and successfully to address many questions on the multifaceted ecology of pyrrolizidine alkaloids. We aim to encourage field researchers in the tropics to employ PA-baiting as a valuable research method in this field of integrative biology.

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Attractants are a powerful tool for pest management. The lack of specific attractants for the South American fruit fly, Anastrepha fraterculus, a complex of cryptic species of great economic importance in South America, makes it difficult to monitor the pest in the field. The γ-lactone male sex and aggregation pheromones of several Anastrepha species, naturally released in a 7:3 epianastrephin to anastrephin ratio, and a structurally related naturally occurring γ-lactone ((±)-trans-tetrahydroactinidiolide) with gem-dimethyl groups (dimethyl) at C(4), were evaluated as potential attractants of this species. Different age and mating conditions of A. fraterculus males and females were evaluated during electroantennography (EAG) and field cage experiments in which polymeric lures were deployed to contain 100 mg of attractant. Epianastrephin and dimethyl were EAG+ for all fly conditions, with epianastrephin eliciting the highest response for both sexes and immature flies showing greater responsiveness than mature flies. In the field cage experiments, immature flies were only attracted to leks; virgin females were attracted to leks, dimethyl, and both epianastrephin-anastrephin formulations (95 and 70 wt.% epianastrephin); mature-mated males were attracted to leks, dimethyl and 70 wt.% epianastrephin; and mature-mated females were only attracted to leks. Our bioassays showed a promising performance of the analog dimethyl since it elicited the same response as epianastrephin, requires fewer steps to synthesize, and contains one less chiral center than the natural pheromones. The attraction to leks was recorded for all mating conditions and ages of flies and suggests that air-borne volatiles of calling males contain cues that could act as sensory traps. The addition of any of these compounds in the synthetic attractants may result in a greater attraction and thus deserves further evaluation. Dose-response experiments will provide additional information to move a step forward and validate the results obtained in open-field conditions.

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Hand-held insect nets are the standard method for capturing vector mosquitoes of sylvatic arboviruses; however, occupational risks and biases due to individual skill and attractiveness are important limitations. The use of chemical attractants and automatic traps could be an alternative to resolve these limitations. This study compares the yields achieved using nets with those employing electrical traps with CO2 and BG-Lure®, near the ground and in the canopy strata (6.0 and 8.0 m high). The study was conducted at the Cantareira State Park, which is in the Brazilian Atlantic Forest biome. In the 18 collections performed, 3570 specimens of 52 taxa were obtained. The most frequent species captured near the ground were Wyeomyia confusa and Limatus durhamii, whereas Sabethes albiprivus, Sabethes purpureus, and Haemagogus leucocelaenus were the most frequent in the canopy. The nets resulted in greater species richness and abundance, followed by the trap employing CO2. The combination of CO2 traps with BG-Lure® did not improve performance. The use of BG-Lure® alone resulted in low abundance and a low number of species. Our results demonstrate that the use of traps with CO2 can be complementary to collections with nets; however, for species of epidemiological interest such as those of the genera Haemagogus and Sabethes, especially in the canopy, the net remains the method of choice.

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Obtaining colonies of stingless bees in the wild for the formation or expansion of meliponaries and other purposes is permitted by law in Brazil using bait containers or trap nests, and other non-destructive methods. We tested the efficiency of trap nests made from plastic bottles for attraction and nesting of stingless bees in the central Brazilian Amazon. We used 2-L and 5-L bottles and three types of attractants (cerumen and geopropolis from Melipona seminigra, M. interrupta and a mix of the two). We used 216 trap nests distributed in three experimental areas during 13 months. Visitation by six species of stingless bees in 58 (26.9%) trap nests, and nesting by three species in 12 (5.6%) trap nests in two areas near meliponaries was recorded. There was no significant difference between trap-nest size, nor among attractants for visitation or nesting, suggesting that the availability of cavities or hollows is more important than odor for nesting. Monthly pooled visitation and nesting events were not correlated with monthly rainfall. Based on our results, we can conclude that, despite the low capture rate, the acquisition of swarms through nest traps is a viable alternative to obtain new colonies of stingless bees for meliponaries.(AU)

A obtenção de colônias de abelhas sem ferrão na natureza, para a formação ou ampliação de meliponários e outras finalidades, é permitida por lei no Brasil usando recipientes-isca ou ninho-isca, ou outros métodos não destrutivos. Nós testamos a eficiência do ninho-isca feito de garrafa plástica para atração e nidificação de abelhas sem ferrão na região da Amazônia central brasileira. Foram utilizadas garrafas de 2 L e 5 L e três tipos de atrativos (cerume e geoprópolis de Melipona seminigra, M. interrupta e uma mistura dos dois). Foram utilizados 216 ninhos-isca distribuídos em três áreas experimentais durante 13 meses. Foi registrada a visitação de seis espécies de abelhas sem ferrão em 58 (26,9%) dos ninhos-isca e a nidificação de três espécies em 12 (5,6%) dos ninhos-isca em duas áreas próximas a meliponários. Não houve diferença significativa entre o tamanho do ninho-isca, nem entre os atrativos na visitação ou nidificação, sugerindo que a disponibilidade de cavidades ou ocos é mais importante do que o odor para nidificação. Os dados mensais conjuntos de eventos de visitação e nidificação não foram correlacionados com a precipitação mensal. Baseados nos nossos resultados podemos concluir que, apesar da baixa taxa de captura, a aquisição de enxames por meio de ninho-isca é uma alternativa viável para obtenção de novas colônias de abelhas sem ferrão para meliponários.(AU)

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Studies have demonstrated that the addition of preservatives mixed with food attractants have provided a more expressive attractiveness for fruit fly adults. The objective of the study was to evaluate the capture of Anastrepha fraterculus (Wiedemann, 1830) adults when the addition of borax and/or benzalkonium chloride preservative in BioAnastrephaTM and Isca Samaritá TradicionalTM food attractants compared to CeraTrapTM (control, no preservatives added) in peach orchards. As well as, verifying the effect over non-target insects. BioAnastrephaTM, Isca Samaritá TradicionalTM and CeraTrapTM attractants enabled the capture of A. fraterculus adults when used by themselves in McPhail traps. However, by adding borax and benzalkonium chloride, BioAnastrephaTM and Isca Samaritá TradicionalTM food attractants significantly increased the number of adults captured. Additionally, the number of A. fraterculus adults captured by BioAnastrephaTM attractant + borax was similar to CeraTrapTM attractant over time. Regarding non-target insects, the highest percentages of subjects captured belong to the Coleoptera (4.4 to 11%) and Diptera orders (24.1 to 34.6%) (Drosophilidae family). Nevertheless, insects from the Hymenoptera order [(Formicidae (0.14 to 0.96%), Vespidae (0.02 to 0.3%), and Apidae (0.04 to 0.9%)] families. Neuroptera (0.02 to 0.98%) and Lepidoptera (0.09 to 0.7%) were also captured, although those amounted to less than 1% of the A. fraterculus total. Adding borax and benzalkonium chloride to BioAnastrephaTM and Isca Samaritá TradicionalTM food attractants potentialize the effect of A. fraterculus capture in monitoring traps. Also, adding preservatives made attractants more durable, consequently, the need to replace attractants was not as frequent.

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Anastrepha ludens is a key pest of mangoes and citrus from Texas to Costa Rica but the mechanisms of odorant perception in this species are poorly understood. Detection of volatiles in insects occurs mainly in the antenna, where molecules penetrate sensillum pores and link to soluble proteins in the hemolymph until reaching specific odor receptors that trigger signal transduction and lead to behavioral responses. Scrutinizing the molecular foundation of odorant perception in A. ludens is necessary to improve biorational management strategies against this pest. After exposing adults of three maturity stages to a proteinaceous attractant, we studied antennal morphology and comparative proteomic profiles using nano-LC-MS/MS with tandem mass tags combined with synchronous precursor selection (SPS)-MS3. Antennas from newly emerged flies exhibited dense agglomerations of olfactory sensory neurons. We discovered 4618 unique proteins in the antennas of A. ludens and identified some associated with odor signaling, including odorant-binding and calcium signaling related proteins, the odorant receptor co-receptor (Orco), and putative odorant-degrading enzymes. Antennas of sexually immature flies exhibited the most upregulation of odor perception proteins compared to mature flies exposed to the attractant. This is the first report where critical molecular players are linked to the odor perception mechanism of A. ludens.

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The citrus borer, Diploschema rotundicolle, is a Neotropical longhorn beetle that has become a serious citrus pest in southern South America. Management strategies for this insect rely on trimming off damaged shoots, which is expensive and inefficient. We studied the chemical communication system in D. rotundicolle in search of attractants for monitoring or control. GC-MS and enantioselective GC analyses of volatile extracts from field-collected adults showed that males produce (R)-3-hydroxy-2-hexanone, irregularly accompanied by minor amounts of 2,3-hexanediol (all four stereoisomers) and 2,3-hexanedione. Males emit the compounds only at night, when the adults are active. GC-EAD analyses of natural and synthetic compounds showed that both male and female antennae respond to the natural enantiomer (R)-3-hydroxy-2-hexanone, suggesting that it may function as an aggregation-sex pheromone as seen in many cerambycines. The non-natural (S) enantiomer as well as the minor component 2,3-hexanediol did not trigger antennal responses. Field tests with the racemic 3-hydroxy-2-hexanone, enantiomerically pure (R)-3-hydroxy-2-hexanone, as well as a mixture of racemic 3-hydroxy-2-hexanone and 2,3-hexanediol, showed in all cases low capture levels of D. rotundicolle. However, increasing the elevation of the trap and the emission rate of dispensers enhanced field captures in traps baited with racemic hydroxyketone. Incidental catches of another native cerambycine, Retrachydes thoracicus, in traps baited with 3-hydroxy-2-hexanone are also reported. This is the first report of pheromone chemistry in the genus Diploschema and in the tribe Torneutini, reaffirming the pheromone parsimony well established for the Cerambycinae. Potential factors explaining the weak attraction of D. rotundicolle in the field are discussed.

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The rice stalk stink bug, Tibraca limbativentris, is an important rice pest in Brazil with a high invasive potential for Mexico and the USA. The sex pheromone of this species was previously identified as a combination of two stereoisomers of 1,10-bisaboladien-3-ol (zingiberenol), but the absolute configurations of these sesquiterpenes were not determined, neither were their effect(s) on T. limbativentris behavior evaluated. In this study, using two chiral columns, we compared retention times of the two natural 1,10-bisaboladien-3-ol stereoisomers from air-entrainment samples of male T. limbativentris with those of synthetic stereoisomers of 1,10-bisaboladien-3-ol. The results showed that T. limbativentris males produce (3S,6S,7R)-1,10-bisaboladien-3-ol (1) and (3R,6S,7R)-1,10-bisaboladien-3-ol (5) as their sex pheromone. Two new minor, male-specific components were also identified as cis and trans isomers of 2,10-bisaboladien-1-ol (sesquipiperitol). Y-tube olfactometer bioassays showed that the major (3S,6S,7R) isomer 1 was essential for attraction of T. limbativentris females, but the minor (3R,6S,7R) isomer 2 was not, nor did it show synergistic/antagonistic effects when added to the major isomer. The (1S,6S,7R) and (1R,6S,7R) stereoisomers of sesquipepiritol also attracted T. limbativentris females.

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BACKGROUND: Small-scale farmers often take a double hit from pests such as tephritid fruit-flies. The high price of products against fruit-flies, together with the higher risk of reinfestation from neighboring orchards, limits options for control. Therefore, management requires low-cost local products and concerted action. Peach production in central Bolivia is increasingly affected by invasive Ceratitis capitata. To provide locally sustainable techniques that could incentivize area-wide cooperation of growers, we tested efficiency and specificity of low-cost lures and traps compared with commercial lures and traps (Tephritrap). RESULTS: In the laboratory, the local fermented beverage 'chicha' and baker's yeast were equally or more attractive than commercial lures. Both chicha and baker's yeast trapped more flies in field (average FTD 10.31 and 9.49), whereas commercially hydrolyzed protein lure (4.71) or Torula yeast (6.82). However, many non-target species were caught (57.3% and 53.4%). Of the six PET bottles-based traps used, the T-trap caught a similar number of flies (average FTD 5.55), but fewer beneficial insects (0.16) compared to the Tephritrap (0.92). CONCLUSIONS: This study provides fruit growers with an economical and effective method to capture large numbers of C. capitata, suitable to be part of integrated pest management programs for fruit fly control. © 2018 Society of Chemical Industry.

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Nocturnal flowering plants often release strong scents to attract their pollinators. Among night active flower visitors are cyclocephaline scarab beetles, which have been demonstrated to respond to uncommon volatile organic compounds released in high amounts by their host plants. In Araceae, the molecular structure of several such compounds is yet to be unveiled. We investigated headspace floral scent samples of Philodendron squamiferum, Thaumatophyllum mello-baretoanum, and Xanthosoma hylaeae by a variety of approaches, leading to the identification of novel compounds. Dehydrojasmone, (Z)-4-methylene-5-(pent-2-en-1-yl)cyclopent-2-en-1-one (1), (Z)-3-methylene-2-(pent-2-en-1-yl)cyclopentyl acetate (isojasmyl acetate, 3), and (E)-4,8-dimethylnona-1,3,7-trien-5-yl acetate (4) had not been previously reported, while full analytical data of the recently described (Z)-3-methylene-2-(pent-2-en-1-yl)cyclopentan-1-ol (isojasmol, 2) are presented here. All these compounds are derived from more common precursors, (Z)-jasmone and (E)-4,8-dimethyl-1,3,7-nonatriene, likely through biosynthetic "post-processing".

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The stable fly, Stomoxys calcitrans (Diptera: Muscidae), is a worldwide pest of livestock. Recent outbreaks of stable flies in sugarcane fields in Brazil have become a serious problem for livestock producers. Larvae and pupae found inside sugarcane stems after harvesting may indicate that stable flies use these stems as potential oviposition or larval development sites. Field observations suggest that outbreaks of stable flies are associated with the vinasse and filter cake derived from biomass distillation in sugarcane ethanol production that are used as fertilizers in sugarcane fields. Adult stable flies are attracted to vinasse, which appears to present an ideal larval development site. The primary goal of the present study is to demonstrate the role of vinasse in influencing the sensory physiological and behavioural responses of stable flies, and to identify its associated volatile attractant compounds. Both laboratory and field studies showed that vinasse is extremely attractive to adult stable flies. Chemical analyses of volatiles collected revealed a wide range of carboxylic acids, alcohols, phenols and aldehydes as potential attractant compounds. These newly identified attractants could be used to develop a tool for the attractant-baited mass trapping of stable flies in order to reduce infestations.

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The use of bee attractants, Bee-Q and Fruit BoostTM in the pollination of niger was evaluated. Bee visitations to niger flowers were observed for two weeks and an estimation of seed yield was determined. Different concentrations of Bee-Q and Fruit boostTM were evaluated to understand honeybee visitation patterns on the target crop and pollination efficiency. Results indicate that applications of Bee-Q at 12.5 g/l and Fruit boost at 0.75 ml/l on niger plots significantly increased the number of bee foragers over control plots. In addition, plots sprayed with these bee attractants significantly enhanced the seed set, seed weight, and germination of niger. This study suggests that pheromone-based bee attractants applied to niger can increase the marginal percentage of bee visitation, seed yield, and percent germination.

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Studies have shown that both carbon dioxide (CO2) and octenol (1-octen-3-ol) are effective attractants for mosquitoes. The objective of the present study was to evaluate the attractiveness of 1-octen-3-ol and CO2 for diurnal mosquitoes in the southeastern Atlantic forest. A Latin square experimental design was employed with four treatments: CDC-light trap (CDC-LT), CDC-LT and 1-octen-3-ol, CDC-LT and CO2 and CDC-LT with 1-octen-3-ol and CO2. Results demonstrated that both CDC-CO2 and CDC-CO2-1-octen-3-ol captured a greater number of mosquito species and specimens compared to CDC-1-octen-3-ol; CDC-LT was used as the control. Interestingly, Anopheles (Kerteszia) sp. was generally attracted to 1-octen-3-ol, whereas Aedes serratus was the most abundant species in all Latin square collections. This species was recently shown to be competent to transmit the yellow fever virus and may therefore play a role as a disease vector in rural areas of Brazil.

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OBJETIVO: Determinar el efecto de los compuestos volátiles en las casas sobre la respuesta conductual del vector del paludismo Anopheles albimanus. MATERIAL Y MÉTODOS: El estudio se realizó en enero de 2006 en el ejido Nueva Independencia, municipio de Suchiate, Chiapas. Se colectaron compuestos volátiles dentro de casas y los extractos se probaron sobre hembras sin alimentar en un olfatómetro en "Y". Los extractos se analizaron mediante cromatografía de gases-espectrometría de masas (CG-EM). RESULTADOS: Se obtuvieron 28 extractos, 12 presentaron respuesta de atracción y dos de repelencia. Los análisis por CG-EM indicaron variación en la presencia de compuestos volátiles y no se vincularon con compuestos específicos indicativos de algún efecto. CONCLUSIONES: Los volátiles en casas presentaron efecto de atracción y repelencia para An. albimanus. No se reconoció un patrón definido en cuanto a la presencia de compuestos químicos característicos y la respuesta obtenida.

OBJECTIVE: To determine effects of volatile compounds in homes on the behavioral response of Anopheles albimanus. MATERIAL AND METHODS: The study was conducted in January 2006, in the village of Nueva Independencia village, Suchiate, Chiapas. Volatile compounds were collected inside homes and the extracts were tested on unfed females in a Y-olfactometer. Extracts were analyzed in a gas chromatography-mass spectrometry system (GC-MS). RESULTS: Twenty eight extracts were obtained, twelve presented attraction and two repellency responses. GC-MS analyses of the extracts indicated variation in the volatile compound present in the extracts, but could not associated specific compounds with any particular effect. CONCLUSIONS: Within homes, volatiles presented attraction and repellency responses to An. albimanus. A definate pattern concerning the presence of a characteristic chemical compound and the observed response was not found.

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A broca-do-café é a praga mais importante do cafeeiro. Provoca prejuízos em quantidade e qualidade da produção. Normalmente, é controlada por aplicações de inseticidas. Estratégias alternativas de manejo são necessárias principalmente pelo aumento da produção e demanda por produtos orgânicos. O uso de armadilhas para manejo da broca é revisado. A cor, o modelo da armadilha, os atraentes e as taxas de liberação são fatores diretamente relacionados com a eficiência das armadilhas. Metanol e etanol são os compostos utilizados como atraentes. Ocorrem interações entre fatores na atração da broca. As condições ambientais nas quais o cafeeiro é cultivado também devem influenciar as capturas. Estes aspectos podem explicar algumas diferenças em resultados de alguns estudos. Resultados conflitantes também são verificados no que se refere à eficiência das armadilhas quando utilizadas como estratégia única de controle no campo. Pesquisas adicionais devem ser incentivadas para entender com mais profundidade as interações entre a broca e a planta de café. Da mesma forma, deve-se estudar as interações dos vários fatores intrínsecos das armadilhas e destes fatores com o ambiente no qual a armadilha será instalada. O uso das armadilhas, associadas a outras estratégias de redução populacional da praga, é prática recomendável para manejo da broca

The Coffee berry borer (CBB) is the most important pest in the coffee plantings. Losses are due to quality andquantity reductions. In most plantings, CBB is controlled using insecticides. Alternative management strategiesare strongly demanded due to increasing production and demand for organic products. This paper revises theuse of traps for CBB management. Color and trap designs, attractants and release rates are the factors directlyrelated to trap efficiency. Methanol and ethanol mixture is used as attractant. Interactions among these factorsin the CBB attraction are reported. Environment conditions under which the coffee plantings are conductedinfluence trap captures. These aspects may explain some differences in results for different studies. Conflictingresults are also found in relation to traps efficiency when they are used as a unique control strategy in thefield. Additional research may be encouraged to understand more deeply the interactions between the CBBand coffee plant. In the same way, we must study the interactions of the several intrinsic factors of the trapsand the environment. The use of the trap, associated with other strategies to reduce pest population, is arecommended strategy for CBB management

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The Coffee berry borer (CBB) is the most important pest in the coffee plantings. Losses are due to quality and quantity reductions. In most plantings, CBB is controlled using insecticides. Alternative management strategies are strongly demanded due to increasing production and demand for organic products. This paper revises the use of traps for CBB management. Color and trap designs, attractants and release rates are the factors directly related to trap efficiency. Methanol and ethanol mixture is used as attractant. Interactions among these factors in the CBB attraction are reported. Environment conditions under which the coffee plantings are conducted influence trap captures. These aspects may explain some differences in results for different studies. Conflicting results are also found in relation to traps efficiency when they are used as a unique control strategy in the field. Additional research may be encouraged to understand more deeply the interactions between the CBB and coffee plant. In the same way, we must study the interactions of the several intrinsic factors of the traps and the environment. The use of the trap, associated with other strategies to reduce pest population, is a recommended strategy for CBB management.

A broca-do-café é a praga mais importante do cafeeiro. Provoca prejuízos em quantidade e qualidade da produção. Normalmente, é controlada por aplicações de inseticidas. Estratégias alternativas de manejo são necessárias principalmente pelo aumento da produção e demanda por produtos orgânicos. O uso de armadilhas para manejo da broca é revisado. A cor, o modelo da armadilha, os atraentes e as taxas de liberação são fatores diretamente relacionados com a eficiência das armadilhas. Metanol e etanol são os compostos utilizados como atraentes. Ocorrem interações entre estes fatores na atração da broca. As condições ambientais nas quais o cafeeiro é cultivado também devem influenciar as capturas. Estes aspectos podem explicar algumas diferenças em resultados de alguns estudos. Resultados conflitantes também são verificados no que se refere à eficiência das armadilhas quando utilizadas como estratégia única de controle no campo. Pesquisas adicionais devem ser incentivadas para entender com mais profundidade as interações entre a broca e a planta de café. Da mesma forma, deve-se estudar as interações dos vários fatores intrínsecos das armadilhas e destes fatores com o ambiente no qual a armadilha será instalada. O uso das armadilhas, associadas a outras estratégias de redução populacional da praga, é prática recomendável para manejo da broca.

RESUMO

Responses of Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) larvae to CO2 and their behavior when exposed to host and non host plants were studied in the laboratory. First instar larvae of D. speciosa were used. In a first bioassay, larvae preferred the treatment with CO2, from the reaction of the potassium bicarbonate and acetic acid, in opposition to distillated water. When the behavior of the larvae was observed in response to host plants, a significant higher number of turns was found in corn and popcorn than in common beans, soybean, wheat and sorghum. Sorghum differed from all other treatments with a lower number of turns. Similar values were found in popcorn and corn. The greater distances ranged were found on oats in comparison to pop corn, corn, common beans and sorghum. After contact with sorghum seedlings larvae did not present searching behavior because they fell from the seedling or no movements were saw seen.

As respostas de larvas de Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) ao CO2 e o comportamento destas larvas quando expostas a plantas hospedeiras e não hospedeiras foram estudadas em laboratório. Larvas de primeiro ínstar de D. speciosa foram utilizadas. Num primeiro bioensaio, as larvas preferiram o tratamento com CO2, que foi gerado a partir da reação de bicarbonato de potássio com ácido acético em oposição a água destilada. Quando se observou o comportamento das larvas em relação a plantas hospedeiras, verificou-se que ocorreu um número significativamente maior de "mudanças de direção" em milho e milho pipoca do que em feijão, soja, trigo e sorgo. Este parâmetro foi inferior no sorgo em relação a todos os outros tratamentos. Valores similares foram verificados em milho pipoca e milho (26,2 e 24,2, respectivamente). Em relação a distância percorrida, foram verificadas maiores distâncias na aveia em comparação com milho pipoca, milho, feijão e sorgo. Após o contato das larvas com sorgo, elas não apresentaram comportamento de busca, pois a larva caía da plântula ou não se movia .

RESUMO

Responses of Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) larvae to CO2 and their behavior when exposed to host and non host plants were studied in the laboratory. First instar larvae of D. speciosa were used. In a first bioassay, larvae preferred the treatment with CO2, from the reaction of the potassium bicarbonate and acetic acid, in opposition to distillated water. When the behavior of the larvae was observed in response to host plants, a significant higher number of turns was found in corn and popcorn than in common beans, soybean, wheat and sorghum. Sorghum differed from all other treatments with a lower number of turns. Similar values were found in popcorn and corn. The greater distances ranged were found on oats in comparison to pop corn, corn, common beans and sorghum. After contact with sorghum seedlings larvae did not present searching behavior because they fell from the seedling or no movements were saw seen.

As respostas de larvas de Diabrotica speciosa (Germar) (Coleoptera: Chrysomelidae) ao CO2 e o comportamento destas larvas quando expostas a plantas hospedeiras e não hospedeiras foram estudadas em laboratório. Larvas de primeiro ínstar de D. speciosa foram utilizadas. Num primeiro bioensaio, as larvas preferiram o tratamento com CO2, que foi gerado a partir da reação de bicarbonato de potássio com ácido acético em oposição a água destilada. Quando se observou o comportamento das larvas em relação a plantas hospedeiras, verificou-se que ocorreu um número significativamente maior de "mudanças de direção" em milho e milho pipoca do que em feijão, soja, trigo e sorgo. Este parâmetro foi inferior no sorgo em relação a todos os outros tratamentos. Valores similares foram verificados em milho pipoca e milho (26,2 e 24,2, respectivamente). Em relação a distância percorrida, foram verificadas maiores distâncias na aveia em comparação com milho pipoca, milho, feijão e sorgo. Após o contato das larvas com sorgo, elas não apresentaram comportamento de busca, pois a larva caía da plântula ou não se movia .

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This experiment studied the frequency and behavior of insects on sweet orange flowers, Citrus sinensis (L.) Osbeck, their effect on fruit production (quantity and quality), nectar and pollen collection, and the effectiveness of different attractants. Over three consecutive years, the most frequent visitor to the flowers was Apis mellifera (Africanized). Flowers visited less than ten times showed low fructification. Fruit production was 35.30% greater in uncovered flowers. Fruit mean weight was much greater in uncovered (180.2g) than in covered flowers (168.5g). Fruits from the covered were more acid (1.411g of citric acid/100ml of juice) than the uncovered flowers (1.164g of citric acid/100ml of juice). The number of seeds per bud was higher in the uncovered (1 seed/bud) than in the covered treatment (0.8 seed/bud). Bee-HereR, eugenol, geraniol, citral, and lemon grass extract, mainly diluted in water, were effective in attracting honeybees to orchards. However, these compounds were less effective when diluted in sugar syrup. The same products had variable attractiveness to honeybees in different years.

RESUMO

Adding attractants can improve acceptability of artificial diets by carnivorous fish fry and fingerlings, increasing intake of unpalatable feeds and improving growth rate, while reducing feeding time and feeding wastes. This study aimed to evaluate the effects of levels of inclusion of different attractants in plant protein-based diets on the performance of largemouth bass Micropterus salmoides. Nine hundred juvenile largemouth bass (26.54 ± 1.53 g) conditioned to accept dry, artificial feed were stocked in 60, 90-L polyethylene tanks (15 fish per group) in a completely randomized design trial (n=3). Fish were fed two daily meals ad libitum at 7h00 and 17h00, for 13 days, with a diet (100% plant protein source) containing either soluble fish protein - SFP (0.5, 1.0, 1.5, 2.0, 2.5, and 3.0%); FisharonTM - FA (0.02, 0.04, 0.06, 0.08, 0.10, 0.12%); fish silage - FS (1.0, 2.0, 3.0, 4.0, 5.0, and 6.0%); a positive control diet - pCD (10% fish meal) and a negative control diet - nCD (basal diet without attractants). DL-methionine (98%) and L-lysine (80%) were added automatically by the formulation software to adjust available amino-acid profile of diets. Recorded performance data were: final weight, feed intake, weight gain and feed conversion ratio. Fish fed diet FA0.02 presented the best growth rate, best weight gain and best feed conversion ratio. Fish fed diets containing FS as attractant presented the poorest performance.

A adição de estimulantes pode melhorar a aceitabilidade de dietas artificiais por pós-larvas e alevinos de peixes carnívoros, aumentando a ingestão de alimentos não palatáveis e a taxa de crescimento, reduzindo o tempo de alimentação e perdas alimentares. Investigou-se o uso de atrativos alimentares em dietas formuladas exclusivamente à base de proteína de origem vegetal (PV), e seus efeitos no desempenho de alevinos do carnívoro "black bass", Micropterus salmoides, condicionados a aceitar ração seca. Novecentos juvenis (26,54 ± 1,53 g) foram estocados em 60 aquários de polietileno de 90 L (15 peixes por aquário), em delineamento experimental totalmente ao acaso (n=3), e alimentados ad libitum em duas refeições diárias (7h00 e 17h00), durante 13 dias, com uma dieta basal (100% PV) contendo seis níveis de proteína solúvel de peixe - PSP (0,5, 1,0, 1,5, 2,0, 2,5 e 3,0%); Fisharom®- FA (0,02, 0,04, 0,06, 0,08, 0,10 e 0,12%); silagem de peixe - SP (1,0, 2,0, 3,0, 4,0, 5,0 e 6,0%); um controle positivo (10% de farinha de peixe) e um controle negativo (dieta basal sem atrativos). Os peixes alimentados com a dieta contendo FA 0,02% apresentaram melhor taxa de crescimento, ganho de peso e conversão alimentar. Os peixes alimentados com dietas contendo SP como atrativo apresentaram os piores resultados de desempenho.