A potential mating-type biomarker to detect pathogenic Ganoderma species

Aims@#The basal stem rot disease in oil palm is caused by the pathogenic Ganoderma boninense, which is infectious after mating and forming dikaryotic hyphae. This study was aimed to generate a mating-type biomarker for the detection of pathogenic Ganoderma species.@*Methodology and results@#Mating-type region of Ganoderma was amplified using polymerase chain reaction (PCR) and primers flanking the mating-type region of other basidiomycetes. Amplified fragments were sequenced and were identified as the Ganoderma pheromone receptor gene of matB locus called the gprb2 gene. Using this biomarker, the pheromone receptor gene was detected in a total of 107 pathogenic Ganoderma spp. while the gene was not detected in the non-pathogenic Ganoderma lucidum. Phylogenetic tree analyses of the gene fragment encoding the partial amino acid sequence of gprb2 showed clades of close evolutionary relationship among the 107 pathogenic Ganoderma spp. Phylogenetic analyses using deduced amino acid sequences of the Ganoderma pheromone receptor b2 gene, gprb2 with homologous pheromone receptors of other basidiomycetous fungi revealed high conservation of this pheromone receptor within their respective taxonomy.@*Conclusion, significance and impact of study@#A potential mating-type biomarker was successfully identified that could detect pathogenic Ganoderma spp. The research findings will be helpful in oil palm screening to detect pathogenic Ganoderma spp. and gain further insight into the role of the mating-type loci of Ganoderma towards its pathogenesis in causing the basal stem rot disease of oil palm.

Efficacy of aggregation nano gel pheromone traps on the catchability of Rhynchophorus ferrugineus (Olivier) in Egypt / Eficácia das armadilhas de feromônio de nano gel de agregação na capturabilidade de Rhynchophorus ferrugineus (Olivier) no Egito

Field experiments were carried out in the reclaimed land east of Cairo-Alexandria Desert Road, Village of Wardan, Giza Governorate, Egypt, to evaluate the impact of using nano-gels pheromone for the first time on the attraction of the RPW adults by pheromone traps compared to the control which is normal pheromone during two successive seasons in 2018 and 2019. Also, this study aimed to compare the efficacy of two types of trap, traditional trap (type 1) and dry funnel trap (type 2) in capturing of RPW adults. Results revealed that the nano gel pheromone traps attracted significantly more adults with an average of (4.26 and 3.56) adults/trap and total of (55.33 and 46.33) adults/trap compared to control with an average (2.69 and 2.46) and total of (35.00 and 32.00) adults/trap for the two seasons 2018 and 2019 respectively. Results indicated that the use of nano gel pheromone for the first time in field improved the trap catchability to RPW adults by 22.51 and 18.30% of total number of RPW adults captured throw out the two successive seasons respectively. In addition, there was no significant difference between the total numbers of RPW adults collected by the two tested type of traps over the two successive seasons. Furthermore, the sex ratio between males and females of total collected RPW adults found to be1: 1.43 and 1: 1.94 at 2018 and 2019 respectively.

Experimentos de campo foram realizados na terra recuperada a leste da estrada do deserto de Cairo-Alexandria, vila de Wardan, província de Giza, Egito, para avaliar o impacto do uso de feromônio de nano géis pela primeira vez na atração de adultos RPW por armadilhas de feromônio comparado ao controle que é o feromônio normal durante duas temporadas sucessivas em 2018 e 2019. Além disso, este estudo teve como objetivo comparar a eficácia de dois tipos de armadilha, armadilha tradicional (tipo 1) e armadilha de funil seco (tipo 2) na captura de RPW adultos. Os resultados revelaram que as armadilhas de nano gel de feromônio atraíram significativamente mais adultos, com uma média de (4,26 e 3,56) adultos/armadilha e total de (55,33 e 46,33) adultos/armadilha em comparação ao controle com uma média (2,69 e 2,46) e total de (35.00 e 32.00) adultos/armadilha para as duas temporadas 2018 e 2019, respectivamente. Os resultados indicaram que o uso de feromônio nano gel pela primeira vez em campo melhorou a capturabilidade de armadilhas para adultos com RPW em 22,51 e 18,30% do número total de adultos com RPW capturados durante as duas estações sucessivas, respectivamente. Além disso, não houve diferença significativa entre o número total de adultos RPW coletados pelos dois tipos de armadilhas testados ao longo das duas estações sucessivas. Além disso, a proporção sexual entre homens e mulheres do total de adultos coletados de RPW foi de 1: 1,43 e 1: 1,94 em 2018 e 2019, respectivamente.

Weather based prediction model for beet armyworm (Spodoptera exigua Hubner) in chickpea

Aim: The study aimed to develop and validate weather based prediction model for beet armyworm (Spodoptera exigua) population in chickpea through adult catches in pheromone traps. Methodology: The data on adult trap catches of S. exigua were recorded daily and weekly means were computed. Log transformed trap catches data were used for correlation with weather parameters of current week, 1-lag, 2-lag and 3-lag weeks. Thereafter, multiple-linear regression analysis was done and a model was developed. The prediction model of S. exigua was validated with the appropriate statistical tools. Results: Peak incidence of S. exigua was recorded during 45th standard meteorological week (SMW) with 15.6 moths per trap per week. Amongst current, 1-lag, 2-lag and 3-lag week weather parameters, the male moth population had significant positive correlation with maximum temperature (Tmax) and minimum temperature (Tmin), and negative correlation with morning relative humidity (RH1) of 2-lag week. The sunshine hours/day (SSH) of current week had a significant negative association with S. exigua male moth catches, while the soil temperature (ST) of 2-lag week had highest positive correlation with trap catches. Regression equation was computed by regressing male moth catches of S. exigua against weather data of weeks with highest correlation coefficient. Interpretation: Often, pest-weather models are developed based on current week weather factors. However, it has been witnessed in this study that weather of preceding weeks (up to 3-lag) may also influence the pest population, and thus it needs to be considered for proper understanding of pest dynamics

Identification and evaluation of (3Z, 6Z, 8E)-dodeca-3, 6, 8-trien-1-ol as the trail following pheromone on Microcerotermes exiguous (Isoptera:Termitidae) / Identificación y evaluación de (3Z, 6Z ,8E)-dodeca-3, 6, 8-trien-1-ol como feromona de camino de Microcerotermes exiguus (Isoptera:Termitidae)

Abstract Trail-following pheromone is one of the most important semiochemical in termites. This pheromone is responsible for the recruitment of individuals from the colony to perform different tasks. The aim of this work was to isolate and identify the trail-following pheromone of Microcerotermes exiguus (Isoptera: Termitidae), a typical termite from the Neotropic, that is considered pest in some crops. Subterranean nest of M. exiguus were collected with a shovel in Caracas, Venezuela in 2010. Different chemical micro-reactions combined with chromatographic analysis of solvent extracts, as well as solid phase microextraction analyses (SPME) were applied to termite sternal glands; besides, some behavioral biossays were undertaken. A peak in the chromatograms from extracts (retention index: 1 483), presented a fragmentation pattern with m/z ions: 41; 55; 67; 79; 91; 105; 119; 135; 142; 180, this result alongside behavioral assays allowed us to conclude that (3Z,6Z,8E)-dodeca-3, 6, 8-trien-1-ol (DTOH) acts as the main component of the trail following pheromone. The estimated optimum concentration for termite recruitment and orientation was around 1 pg/cm, being statistically comparable to the value on trails marked with whole body extracts at concentration of 1 worker/cm. The period of time that this compound takes to recruit other colony members is 13.67 ± 5.76 s and lasts up to two hours. Both analytical and behavioral results provided better understanding on the chemical communication of M. exiguus. This information could be used for the future development of newer pest control methods. Rev. Biol. Trop. 66(1): 303-311. Epub 2018 March 01.

Resumen La feromona de camino es uno de los semioquímicos más importantes en las termitas. Esta feromona es responsable del reclutamiento de individuos de la colonia para realizar diversas tareas. El objetivo de este trabajo fue aislar e identificar la feromona de camino de Microcerotermes exiguus (Isoptera: Termitidae), que es una termita típica del Neotrópico, considerada como plaga en algunos cultivos. Nidos subterráneos de M. exiguus fueron recolectados en Caracas, Venezuela en el 2010. Se realizaron diferentes micro-reacciones químicas combinadas con el análisis cromatográfico de los extractos en solventes, así como el de la microextracción en fase sólida (SPME) de las glándulas esternales de las termitas; además de algunos bioensayos de comportamiento. Un pico en los cromatogramas de los extractos (índice de retención:1 483), presentó un patrón de fragmentación con los iones m/z: 41; 55; 67; 79; 91; 105; 119; 135; 142; 180, este resultado junto con los ensayos comportamentales, nos permitieron concluir que el (3Z,6Z,8E)-dodeca-3, 6, 8-trien-1-ol (DTOH) es el compuesto principal de la feromona de camino. La concentración óptima estimada para el reclutamiento y la orientación se encuentra alrededor de 1 pg/cm, siendo estadísticamente comparable al valor en los caminos trazados con extractos de cuerpo entero de 1 obrera /cm. El tiempo que toma este compuesto para reclutar a otros miembros de la colonia es de aproximadamente 13.67 ± 5.76 s y se mantiene hasta por dos horas. Los resultados analíticos y de comportamiento proporcionan una mejor comprensión de la comunicación química de M. exiguus, y dicha información podría ser utilizada para el desarrollo de nuevos métodos de control de plagas.

Hierarchical establishment of information sources during foraging decision-making process involving Acromyrmex subterraneus (Forel, 1893) (Hymenoptera, Formicidae)

ABSTRACT During foraging, worker ants are known for making use of many information sources to guide themselves in external environments, especially individual (memory) and social (trail pheromone) information. Both kinds of information act in a synergic way, keeping the foraging process efficient and organized. However, when social and individual information is conflicting face a trail bifurcation, it is necessary to establish a hierarchical order so prioritizing one of them. This study aims to verify which information (social or individual) is prioritized by Acromyrmex subterraneus workers when facing a bifurcation in a Y-trail system. Only one branch of the Y-trail leads to food resource and it had a section covered by filter paper where trail pheromone was deposited by workers. Pheromone deposition was here estimated by worker flow. After an individually marked forager (target-worker) made 1, 3 or 5 trips to the food resource, the filter paper was transferred to the branch which did not lead to the food. The time spent by target workers on branch selection and their right choice (branch with food) frequency were registered. Regardless of the target worker's previous trips to the resource, right choice frequency stood over 70%. In addition, the number of previous trips did not influence the time spent on decision making. However, the higher the flow of workers, the longer the time spent on decision making. By simulating a situation with conflicting information, it was possible to verify that a hierarchical order is established by A. subterraneus, which prioritized individual information (memory).

Activation of the Mating Pheromone Response Pathway of Lentinula edodes by Synthetic Pheromones

Pheromone (PHB)-receptor (RCB) interaction in the mating pheromone response pathway of Lentinula edodes was investigated using synthetic PHBs. Functionality of the C-terminally carboxymethylated synthetic PHBs was demonstrated by concentration-dependent induction of a mating-related gene (znf2) expression and by pseudoclamp formation in a monokaryotic strain S1-11 of L. edodes. Treatment with synthetic PHBs activated the expression of homeodomain genes (HDs) residing in the A mating type locus, and of A-regulated genes, including znf2, clp1, and priA, as well as genes in the B mating type locus, including pheromone (phb) and receptor (rcb) genes. The synthetic PHBs failed to discriminate self from non-self RCBs. PHBs of the B4 mating type (B4 PHBs) were able to activate the mating pheromone response pathway in both monokaryotic S1-11 and S1-13 strains, whose B mating types were B4 (self) and B12 (non-self), respectively. The same was true for B12 PHBs in the B4 (non-self) and B12 (self) mating types. The synthetic PHBs also promoted the mating of two monokaryotic strains carrying B4-common incompatible mating types (A5B4 × A1B4). However, the dikaryon generated by this process exhibited abnormally high content of hyphal branching and frequent clamp connections and, more importantly, was found to be genetically unstable due to overexpression of mating-related genes such as clp1. Although synthetic PHBs were unable to discriminate self from non-self RCBs, they showed a higher affinity for non-self RCBs, through which the mating pheromone response pathway in non-self cells may be preferentially activated.

Vetor ou vetores? Capacidade vetorial e estratégias de controle / Vector or vectors? Vectorial capacity and control strategies

Variáveis relacionadas a fatores epidemiológicos, ao ambiente, ao agente etiológico, ao vetor e aos reservatórios parecem atuar na determinação dos diferentes cenários de transmissão da leishmaniose visceral no Brasil. No estado de São Paulo a leishmaniose visceral (LV) não apresenta um padrão epidemiológico homogêneo por todas suas regiões, parecendo refletir uma multitude de cenários propícios para a ocorrência da transmissão dentro do território Paulista. Lutzomyia longipalpis é composta por um complexo de espécies das quais duas são encontradas no Estado de São Paulo e parecem possuir diferença na capacidade vetorial. É provável que essa diferença seja o fator determinante na caracterização dos diferentes padrões epidemiológicos observados nas diferentes regiões do Estado. No presente estudo, procuramos determinar a distribuição temporal e geográfica das espécies do complexo Lu. longipalpis, dos casos caninos e dos casos humanos de LV como elementos chave para ajudar na caracterização de alguns cenários de transmissão da doença e apontar áreas de maior risco para a aquisição da doença. Por outro lado, a recente e inesperada ocorrência de transmissão da LV em localidades sem a presença da Lu. longipalpis, caracteriza mais um novo cenário, onde a transmissão da Leishmania infantum ao homem se mostrou possível, configurando um novo desafio para as autoridades da saúde pública.

Variables related to epidemiological factors, etiologic agent, environment, vector and reservoirs seem to act in determining the different scenarios of transmission of visceral leishmaniasis (VL) in Brazil. In the state of São Paulo, VL does not present a homogeneous epidemiological pattern across all its regions, seeming to reflect a multitude of scenarios conducive to the occurrence of transmission within Paulista territory. Lutzomyia longipalpis is composed of a complex of species of which two are found in the state of São Paulo and appear to have a difference in vector capacity. It is likely that this difference is the determining factor in the characterization of the different epidemiological patterns observed in the different regions of the State. In the present study, we sought to determine the temporal and geographic distribution of Lu. longipalpis species, canine cases and human cases of VL as key elements to help characterize some scenarios of transmission of the disease and to indicate areas of greater risk for disease acquisition. The recent and unexpected occurrence of VL transmission in localities without the presence of Lu. longipalpis characterizes another new scenario, where other species of san flies can transmit Leishmania infantum to man and configuring a new challenge for public health authorities.

Metabolic engineering of (E)-β-farnesene synthase genes for aphid-resistant genetically modified plants / 生物工程学报

Aphids are major agricultural pests that cause significant yield losses of crops each year. (E)-β-farnesene (EβF), as the main component of the aphid alarm pheromones, can interrupt aphid feeding and cause other conspecies in the vicinity to become agitated or disperse from their host plant. Furthermore, EβF can function as a kairomone in attracting aphid predators. EβF synthase genes, which encode enzymes that convert farnesyl diphosphate (FPP) to the acyclic sesquiterpene EβF, have been isolated and characterized from peppermint (Mentha × piperita and Mentha asiatica), Yuzu (Citrus junos), Douglas fir (Pseudotsuga menziesii), sweet wormwood (Artemisia annua) and chamomile (Matricaria recutita), respectively. Transgenic plant overexpressing EβF synthase genes has been one of the most efficient strategies for aphid management. In this review, the current statuses of transgenic plants engineered for aphid resistance were summarized. The plant-derived EβF synthase genes with their potential roles in aphid management via genetic-modified (GM) approaches were reviewed. The existing problem in GM plants with EβF synthase gene, such as low EβF emission was usually detected in the transgenic plant, was discussed and the development direction in this area was proposed.

Effect of a synthetic analogue of the feline facial pheromone on salivary cortisol levels in the domestic cat / Efeito do análogo sintético do feromônio facial felino sobre o nível de cortisol salivar de gatos domésticos

This study aimed to evaluate the ability of a saliva collection device (Salivette®) to measure cortisol levels in saliva samples of domestic cats and to assess the effect of a synthetic analogue of the feline facial pheromone fraction F3 (Feliway®) on cortisol levels. A total of 28 domestic cats from a private high-quality sanctuary were sampled before exposure to the facial pheromone and after 35 days of exposure. Two pheromone devices were placed in the area where the animals ate to guarantee the exposure of all cats. The collecting device yielded a sufficient volume of saliva (≥0.20mL) to allow cortisol measurement. Cortisol measurements ranged from 0.02g/dL to 0.16µg/dL, with a difference between before (42.1%) and after (62.6%) exposure to the pheromone (F=3.2351; p≤0.0002). No difference in cortisol levels was observed between before (x =0.078µg/dL) and after (x =0.066µg/dL) (t=1.79; p=0.08) exposure. However, salivary cortisol levels decreased in 75% (21/28) of the cats after exposure (x 2=12.07; p=0.0005), suggesting that the animals have different susceptibilities to the pheromone or that they spent different lengths of time in the area where the pheromone devices were installed.(AU)

O presente estudo avaliou o uso de um dispositivo de coleta salivar (Salivette®) para mensurar o cortisol salivar de gatos domésticos e avaliar o efeito do análogo sintético do feromônio facial felino - fração F3 (Feliway®) sobre seus níveis de cortisol. Um total de 28 gatos domésticos mantidos em gatil particular tiveram amostras de saliva coletadas antes da exposição ao feromônio facial felino e após 35 dias de exposição. Dois difusores de feromônio foram instalados na área onde os animais se alimentavam, a fim de garantir que todos os gatos fossem expostos. Os dispositivos de coleta salivar permitiram a coleta de volume salivar suficiente (≥0,20 mL) para a mensuração do cortisol. Os níveis de cortisol salivar variaram de 0,02g/dL a 0,16ug/dL, com coeficiente de variação de 42,1% antes e de 62,6% após à exposição ao feromônio (F=3.2351; p≤ 0.0002). Não foi verificada diferença entre os níveis de cortisol salivar nas amostras obtidas antes (x =0,078µg/dL) e após (x =0,066µg/dL) (t=1,79; p=0,08) à exposição. Entretanto, os níveis de cortisol salivar diminuíram em 75% (21/28) dos gatos expostos ao feromônio (x 2=12,07; p=0,0005), sugerindo que os animais apresentam susceptibilidade diferente ao feromônio facial sintético ou que passaram períodos de tempo distintos na área onde os difusores foram instalados.(AU)

Research progress on chemical constituents and biological activity of Periplaneta americana / 中草药

In recent years, American cockroach (Periplaneta americana) has gotten more attention from researchers, and researches have demonstrated that it has wide medicinal value, low side effects, and rich resources, which should have good application prospects. This article reviewed chemical constituents and biological activities of P. americana over the past 20 years, so as to provide reference for the further development and utilization.

Bile salt derivatives with novel skeleton from sea lamprey function as putative pheromone / 中国药理学与毒理学杂志

OBJECTIVE The invasive sea lamprey (Petromyzon marinus) has devastated the ecosystem of the Laurentian Great Lakes. Application of pheromones to manipulate adult sea lamprey behavior is among the options considered for alternative sea lamprey control techniques. The male sea lamprey sex pheromone is hypothesized to be possess multiple functions through actions of multiple components, some of which have yet to be characterized. Our objective is to isolate and characterize the bioactive components from water conditioned with sexually mature male sea lamprey. METHODS The water conditioned with sexually mature male sea lamprey was extracted by solid phase extraction and concentrated in vacuo. The compounds were isolated by liquid chromatography and elucidated by spectrometry and spectroscopy. Their biological activities were evaluated by electro-olfactogram recordings and two-choice maze behavioral assays. RESULTS Five novel bile salts, petromyzene A and B and petromyzone A-C, have been characterized. Petromyzene A and B featured either a unique, rearranged side chain or a rare cis-11,12-diol on the steroidal B-ring. Petromyzone A-C represented three novel highly oxidized sulfated bile alcohols possessing different hydroxylation, oxidation, and double bond patterns, which exemplify the chemical diversity of bile salts. These five bile salts were potent odorants that stimulated the adult sea lamprey olfactory epithelium in a concentration dependent manner and showed detection thresholds between 10–13 mol·L-1 and 10–11 mol·L-1(paired t-test, P<0.05). Experi?ments in the two-choice maze showed that all isolated compounds induced behavioral responses in ovulated females. CONCLUSION The five novel compounds are likely additional components of phero?mones released by sexually mature male sea lamprey, and may provide useful behavioral manipulation tools to be implemented with the integrated management of the destructive and invasive sea lamprey in the Laurentian Great Lakes.

Efficacy of aggregation nano gel pheromone traps on the catchability of Rhynchophorus ferrugineus (Olivier) in Egypt

Abstract Field experiments were carried out in the reclaimed land east of Cairo-Alexandria Desert Road, Village of Wardan, Giza Governorate, Egypt, to evaluate the impact of using nano-gels pheromone for the first time on the attraction of the RPW adults by pheromone traps compared to the control which is normal pheromone during two successive seasons in 2018 and 2019. Also, this study aimed to compare the efficacy of two types of trap, traditional trap (type 1) and dry funnel trap (type 2) in capturing of RPW adults. Results revealed that the nano gel pheromone traps attracted significantly more adults with an average of (4.26 and 3.56) adults/trap and total of (55.33 and 46.33) adults/trap compared to control with an average (2.69 and 2.46) and total of (35.00 and 32.00) adults/trap for the two seasons 2018 and 2019 respectively. Results indicated that the use of nano gel pheromone for the first time in field improved the trap catchability to RPW adults by 22.51 and 18.30% of total number of RPW adults captured throw out the two successive seasons respectively. In addition, there was no significant difference between the total numbers of RPW adults collected by the two tested type of traps over the two successive seasons. Furthermore, the sex ratio between males and females of total collected RPW adults found to be1: 1.43 and 1: 1.94 at 2018 and 2019 respectively.

Resumo Experimentos de campo foram realizados na terra recuperada a leste da estrada do deserto de Cairo-Alexandria, vila de Wardan, província de Giza, Egito, para avaliar o impacto do uso de feromônio de nano géis pela primeira vez na atração de adultos RPW por armadilhas de feromônio comparado ao controle que é o feromônio normal durante duas temporadas sucessivas em 2018 e 2019. Além disso, este estudo teve como objetivo comparar a eficácia de dois tipos de armadilha, armadilha tradicional (tipo 1) e armadilha de funil seco (tipo 2) na captura de RPW adultos. Os resultados revelaram que as armadilhas de nano gel de feromônio atraíram significativamente mais adultos, com uma média de (4,26 e 3,56) adultos/armadilha e total de (55,33 e 46,33) adultos/armadilha em comparação ao controle com uma média (2,69 e 2,46) e total de (35.00 e 32.00) adultos/armadilha para as duas temporadas 2018 e 2019, respectivamente. Os resultados indicaram que o uso de feromônio nano gel pela primeira vez em campo melhorou a capturabilidade de armadilhas para adultos com RPW em 22,51 e 18,30% do número total de adultos com RPW capturados durante as duas estações sucessivas, respectivamente. Além disso, não houve diferença significativa entre o número total de adultos RPW coletados pelos dois tipos de armadilhas testados ao longo das duas estações sucessivas. Além disso, a proporção sexual entre homens e mulheres do total de adultos coletados de RPW foi de 1: 1,43 e 1: 1,94 em 2018 e 2019, respectivamente.

Avaliação de uma nova estratégia de controle de Lutzomyia longipalpis (DIPTERA: PSYCHODIDAE), vetor da Leishmania (Leishmania) infantum / Evaluation of a new control strategy of Lutzomyia longipalpis (Diptera: psychodidae), vector of leishmania (leishmania) infantum

Lutzomyia longipalpis é considerado um complexo de espécies capaz de produzirdiferentes quimiotipos de feromônios. A borrifação de inseticida residual para controle deflebotomíneos tem sido incapaz de impedir a propagação da Leishmaniose VisceralAmericana (LVA) no Brasil. Desta forma, novas abordagens com um bom custo-benefíciosão necessárias para controlar populações de Lu. Longipalpis. Mosquiteiros Impregnados deLonga Duração (MILD) oferecem uma nova estratégia de controle e pode ser umaalternativa para borrifação em locais de agregação, tais como galinheiros, fixados em suassuperfícies. O feromônio sintético (±) -9-metilgermacreno-B pode aumentar a atração de Lu.longipalpis em ambientes naturais. Neste estudo, testamos duas estratégias potenciais parao controle de Lu. longipalpis utilizando o feromônio sintético em conjunto com MILDs, com oefeito de "atrair e matar" o vetor no mesmo local. Este estudo foi realizado em GovernadorValadares, Minas Gerais, município de ocorrência de LVA Brasil. Experimentos de campoforam realizados em galinheiros experimentais para comparar a eficácia e efeito residual deinseticidas e mosquiteiros impregnados na mortalidade de Lu. longipalpis, associandoambos os tratamentos com feromônio sintético. Este estudo mostrou que o mosquiteiroimpregnado e a borrifação mataram aproximadamente 100% dos flebotomíneos em até 2meses após os tratamentos. Após 4 meses, o efeito letal do mosquiteiro impregnado reduziupara 69% e inseticida residual para 89%. Concluímos que o MILD é uma ferramentapotencial para matar flebotomíneos em locais de agregação, e o feromônio sintético podeaumentar a sua eficácia atraindo mais insetos para serem mortos pelo mosquiteiro. Maistestes de campo por um longo período são necessários para identificar a viabilidade detratamento de superfícies com mosquiteiros impregnados como parte do programa decontrole da leishmaniose visceral.

Lutzomyia longipalpis is considered a species complex with variability in pheromonesproduction. The residual insecticide spraying to control sand flies have been unable toprevent the spread of the American visceral Leishmaniasis (AVL) across Brazil. In this way,new cost-effective approaches are needed to manage populations of the vector Lu.Longipalpis. Long Lasting Insecticidal Nets (LLINs) offer a new control strategy and can bean alternative of spraying on aggregation sites, such as chicken sheds, fixed in theirsurfaces. The synthetic pheromone (±) -9-methylgermacrene-B can increase attraction of Lu.longipalpis in natural environments. Here, we test two potential strategies for Lu. longipalpiscontrol using the synthetic pheromone in conjunction with LLINs, with the effect of “attractingand killing" the vector at the same site. This study was conducted in Governador Valadares,Minas Gerais, a municipality of the occurrence of AVL in Brazil. Field experiments wereperformed with experimental chicken sheds to compare the efficacy and residual effect ofinsecticide spraying and impregnated netting in Lu. Longipalpis mortality, associating bothtreatments with synthetic pheromone. This study showed that the impregnated netting andspraying killed approximately 100% of sandflies in up to 2 months after treatment. After 4months of exposure treatments, the lethal effect of netting reduced to approximately 69%and residual insecticide to 89%. We concluded that insecticide impregnated netting is apotential tool in killing sand flies in aggregation sites, and synthetic pheromone can increasetheir effectiveness attracting more sand flies to be killed by netting. More field trials for a longperiod are needed to identify the feasibility of treating surfaces with impregnated netting aspart of visceral leishmaniasis control program.

Stud male-originating chemosignals: A luteotrophic agent.

The chemosignals from mating male are found to be responsible for protecting his coital partner against pregnancy failure induced by strange male or food-deprivation. The stud male pheromone not only provides luteotrophic support in female of vulnerable condition but also exerts luteotrophic effect in pregnancy-blocked females by inducing pseudopregnancy. The luteotrophic stimulus rendered by stud male to prevent pregnancy failure is mediated through the main olfactory system, and not through the accessory olfactory system, since the accessory olfactory system is primarily involved in perceiving the luteolytic stimulus produced from strange male for causing pregnancy failure. It has been shown that pericopulatory period seems to be crucial in females in the formation of stud male chemosignals, and the olfactory luteotrophic memory of stud male is further proved to be a short-term one. The precise mechanism involved in accessing and retaining the stud male chemical cues is unclear. In this brief review an attempt has been made to bring out the luteotrophic process of stud male chemosignals, the olfactory pathway and critical period to access the signals. The possible neural mechanism and neural chemistry underlying the formation and recognition of mating male chemical cues are also highlighted.

An alarm pheromone increases the responsivity of amygdaline-hippocampal neurons / Una feromona de alarma incrementa la responsividad de neuronas amigdalino-hipocampales

The capability to perceive and emit alarm substances, such as 2-heptanone, makes animals aware of the presence of danger, leading to some strategies directed towards survival. Strategies of survival involve emotional memory which is processed by deep temporal lobe structures, such as amygdaloid complex and hippocampus. In the Wistar rat, 2-heptanone produces anxiety-like behavior and an increased firing rate of basal amygdaline neurons. However, it is unknown whether 2-heptanone modifies the responsivity of medial amygdaline-hippocampal connection. Therefore, we placed a group (n=10) of Wistar rats in a plexiglass cage impregnated with 2-heptanone. Rats from control group (n=10) were introduced into a similar clean cage. Twenty four hours later we obtained single-unit extracellular recordings from the hippocampus (CA1-CA3) neurons identified by their connection to medial amygdala. Although the basal neuronal firing rate was similar between groups, first order interval distribution histogram analysis showed that 2-heptanone produced shorter intervals of firing rate. Peristimulus histograms indicated that: i) the amygdaline stimulation produces an increased firing rate in hippocampal neurons; and ii) this response is increased and enlarged on the 2-heptanone group. Since a single exposure to an alarm pheromone seems to facilitate the amygdala-hippocampal connection, results suggest the initial formation of contextual memories related with fear.

La percepción olfatoria de feromonas de alarma, como la 2-heptanona, promueve ciertas estrategias de supervivencia con la participación de la memoria emocional, integrada en estructuras del lóbulo temporal, como la amígdala y el hipocampo. En la rata Wistar, la olfacción de 2-heptanona genera conductas sugerentes de ansiedad y un incremento de la tasa de disparo neuronal del núcleo basal de la amígdala. Sin embargo, no se conoce si la 2-heptanona modifica la responsividad de la conexión amígdala medial-hipocampo. Un grupo de ratas Wistar (n=10) fue colocado dentro de una caja de acrílico impregnada con 2-heptanona; el grupo control (n=10) fue introducido en una caja limpia. Veinticuatro horas después se obtuvo el registro unitario extracelular de neuronas del hipocampo (CA1-CA3) identificadas por su conexión con la amígdala medial. Aunque la tasa de disparo basal fue similar entre los grupos experimentales, el histograma de distribución de intervalos de primer orden indicó un predominio de intervalos de breve duración en el grupo 2-heptanona. Los histogramas periestímulo indicaron que: i) las neuronas hipocampales responden con un incremento en la tasa de disparo neuronal ante la estimulación amigdalina; ii) la respuesta es de mayor magnitud y duración en el grupo previamente expuesto a 2-heptanona. Dado que una sola exposición a una feromona de alarma facilita la conexión amígdala medial-hipocampo, los resultados sugieren la formación inicial de una memoria contextual relacionada con el miedo.

Preputial gland activates olfactory receptor neurons in rat: Calcium imaging study using laser scanning confocal microscopy.

The rodent preputial gland is one of the major sources of odours and is reported to be involved in several behavioural activities. However, how the preputial gland initiates the olfactory response to manifest the effects is not known. Olfactory receptor neurons (ORNs) present in the olfactory epithelium are involved in the perception of odorant/pheromonal compounds. In the present study, the response of rat ORNs to preputial gland extract was evaluated by calcium imaging analysis. We found that some rat ORNs responded to the preputial gland extract by exhibiting an intracellular calcium response. By contrast, the ORNs did not respond at all to the foot pad extract (control). The results indicated that the substances contained in the preputial gland might interact with a type of receptor expressed in the female rat ORNs, suggested to manifest the behavioural responses, such as social and sexual interactions. This study provided the first evidence of activation of ORNs by the preputial gland extract.

The host marking pheromone application on the management of fruit flies - a review

The aim of this work was to review the role of the host marking pheromone (HMP) and its application in integrated management programs for the fruit flies. Initially the oviposition behavior of tephritids has been analyzed with emphasis on Ceratitis capitata. The deposition of HMP, which consists in the last stage of the oviposition behavior has been characterized and discussed about evolutive aspects and the biological meaning of the tephritidae communication through the HMP. Finally, the perspectives on the use of HMP in the integrated management of fruit flies have been discussed.

Induction of complete courtship ritual in Amblyomma cajennense using 2,6-dichlorophenol at female-equivalent quantities / Indução dos comportamentos de cortejo em Amblyomma cajennense pelo 2,6-diclorofenol em quantidades equivalentes às das fêmeas

In order to clarify the role of 2,6-dichlorophenol (2,6-DCP) in the courtship of Amblyomma cajennense, sexually mature males that had previously fed on rabbits were tested in bioassays. The males were released onto dummies treated with whole female extract or synthetic 2,6-DCP at a concentration of two female equivalents, or with hexane (control), and their responses were observed. In the presence of both the extract and 2,6-DCP, excitation was observed among the males, expressed in the form of touching and probing the dummy, and mounting occurred readily. The percentages of mounting (73 percent) and tipping over (60 percent) were equal in the two treatments and higher than in the control group (27 and 20 percent, respectively). Relatively short durations of mounting were recorded, and these were statistically similar in all treatments. Almost all instances of mounting resulted in tipping-over behavior. A few isolated cases of males that went directly to ventral positioning without mounting were observed. It was confirmed that 2,6-DCP alone is capable of mediation of mounting behavior in A. cajennense.

Visando elucidar o papel do 2,6-diclorofenol (2,6-DCF) no cortejo de Amblyomma cajennense, machos sexualmente maduros, previamente alimentados em coelhos, foram avaliados em testes biológicos. Os machos foram liberados sobre manequins tratados com um extrato de fêmeas, ou com 2,6-DCF sintético na concentração equivalente a duas fêmeas, ou com hexano (controle), e suas respostas foram observadas. Na presença do extrato e do 2,6-DCF, a excitação dos machos foi expressa na forma de toques e sondagens, e a monta ocorreu rapidamente. As porcentagens de respostas observadas nos dois tratamentos foram iguais, sendo a monta (73 por cento) e retorno na superfície ventral (60 por cento) mais altos que no controle (27 e 20 por cento, respectivamente). Foram observados períodos de monta relativamente curtos, sendo esses estatisticamente iguais em todos os tratamentos, e quase todos resultando em posicionamento ventral. Alguns casos isolados de posicionamento ventral sem monta foram observados. Foi confirmado que o 2,6-DCP sozinho é capaz de mediar o comportamento de monta de A. cajennense.

Sex pheromone and period gene characterization of Lutzomyia longipalpis sensu lato (Lutz & Neiva) (Diptera: Psychodidae) from Posadas, Argentina

Lutzomyia longipalpis s.l. is the primary vector of Leishmania (L.) infantum in the New World. In this study, male Lutzomyia longipalpis specimens from Posadas, Argentina were characterized for two polymorphic markers: the male sex pheromone and the period (per) gene. The male sex pheromone was identified as (S)-9-methylgermacrene-B, the same compound produced by Lu. longipalpis from Paraguay and many populations from Brazil. The analysis of per gene sequences revealed that the population from Argentina is significantly differentiated from previously studied Brazilian populations. Marker studies could contribute to the understanding of the distribution and spread of urban American visceral leishmaniasis, thus aiding in the design of regional surveillance and control strategies.

Reproductive behaviour of Crocidosema (=Epinotia) aporema (Walsingham) (Lepidoptera: Tortricidae): temporal pattern of female calling and mating

Crocidosema aporema (Walsingham) is a major pest of legumes in the southern cone of Latin America. The mating behaviour of two allopatric populations (Uruguay and Brazil) of C. aporema kept in captivity was studied by observing the posture of calling females, the temporal pattern of pheromone emission and mating, and the response of males to calling females in olfactometer tests. Female calling and mating was observed during the scotophase, from the first to the seventh night after adult emergence. Male response was evaluated at night using a single calling female in a Y-shaped olfactometer. Females adopted a characteristic calling posture, extruding the pheromone gland from the tip of the abdomen. Most females started calling during the second scotophase, and all females called from the third, between the fifth and seventh hours after the onset of the scotophase. Most of the couples mated once throughout the experiment, between the third and sixth night and during the middle of the dark phase. Males preferentially chose the female arm in olfactometer tests, considering both the first arm chosen and the number of visits during the observation period. Our results describe for the fi rst time the temporal pattern associated to the reproductive behaviour of C. aporema. We also provide evidence that this tortricid is monoandrous, and that pheromones are used in intersexual communication for mate finding. Our data will be used to optimize the collection of female sex pheromones for chemical characterization in order to develop a monitoring tool for this pest.