Within strain competition of Trichogramma cordubensis (Hymenoptera; Trichogrammatidae)

Competition between one, two, three and four T. cordubensis females is evaluated in the present paper, regarding parasitism and emergence rate at 20°C, using Ephestia kuehniella Zeller (Lep., Pyralidae) eggs as host. As the number of females increased, a decrease in the female average parasitism was demonstrated by a negative linear regression. However, the parasitism difference was only found to be significant (p<O.05) between me population with only one female per egg card (±200 host eggs) and the populations with three and four females per egg card. On the contrary, emergence rate was not affected by the number of females per egg card. No cases of superparasitism occurred

Effect of host availability on Trichogramma cordubensis (Insecta: Hymenoptera) reproductive strategies

The effect of host availability on Trichogramma cordubensis Vargas & Cabello (Hymenoptera, Trichogrammatidae) fecundity and survival rates was analyzed in this study. When hosts were daily provided (either with an unlimited or limited number), wasps had the highest rate of reproduction in the first day of parasitism, decreasing with oscillating values thereafter. When a limited number of hosts was provided with 3 days intervals, the parasitoids reproduction rate was significantly reduced, tending to be equally distributed throughout lifetime. A positive linear relation was found between reproduction and survival: wasps that had daily oviposited had greater longevity than those that had oviposited only every 3 days or did not oviposit. These results suggest that T. cordubensis is able to adjust fecundity schedule as an adaptation to changing hosts resources, which is an important survival feature for this species as host shortage is likely to occur in nature

Ryanair is flying above the clouds

This paper intends to evaluate Ryanair’s share price by the end of 2020 by applying two valuation methods: Multiples and DCF. Ryanair is the largest European Airline Group presenting the highest market share in passengers’ traffic and setting historical lowest average fares in the European airline industry. We believe that Ryanair will keep ahead of competition, once we predict a strong performance for the upcoming years. Our price recommendation is to ‘Buy’ grounded in a price target of 16.77€ and an expected stock return of 16.1% in one year from now

Trichogramma cordubensis (Hym., Trichogrammatidae) : a dynamics study of an Azorean population

4th International Symposium "Trichogramma and other egg-parasitoids", Cairo, Egypt, 4-7 October 1994.Following a previous survey of oophagous parasitoids at Ribeira do Guilherme, São Miguel, Açores, a two-year trial for Lepidoptera eggs was undertaken in order to study their dynamics. Between Novemher 1991 and November 1993 only two parasitoids were discovered: Telenomus sp. (Scelionidae) and T. cordubensis. During winter no eggs parasitized by Trichogramma were collected. From April to November 1992 and June to Novemher 1993, eggs parasitized by Telenomus sp. and T. cordubensis were detected in the field. Telenomus sp. always appeared earlier in the season than Trichogramma. In the present paper, the plant/host/parasitoid interactions are discussed and a comparative analysis is made between the two-year field data

Natural parasitism of Chrysodeixis chalcites and Autographa gamma (Lep., Noctuidae) eggs on tomato fields

A survey for Chrysodeixis chalcites Esper and Autographa gamma L.(Lep.: Noctuidae) eggs was carried oul on tomato fields during the summer season of 1993 and 1994, in order to study egg parasitism. Only two species were found to parasite C. chalcites and A. gamma eggs: Telenomus sp. (Hym.: Scelionidae) and Trichogramma cordubensis (Hym.: Trichogrammatidae). The natural egg parasitism rates were higher in the first year (62.30% for A. gamma and 48.39% for C. chalcites) than in the second (25.16% for A. gamma and 10.91% for C. chalcites). Telenomus sp. was the parasitoid with higher parasitism rates on both host species. Furthermore, this parasitoid always appeared earlier in the fields than T. cordubensis

Estudo do parasitismo dos ovos de Autographa gamma (Lep.: Noctuidae) em culturas de tomate e beterraba

IV Encontro Nacional de Protecção Integrada, 3–4 Outubro, 1997, Angra do Heroísmo, Açores.Este trabalho visou o estudo do parasitismo dos ovos de Autographa gamma (Lepidoptera: Noctuidae) em culturas de tomate e beterraba. Para tal, realizou-se uma prospecção de ovos de A. gamma em dois campos de cultura, um de tomate e outro de beterraba, localizados na Ribeira Grande, ilha de São Miguel. Esta prospecção decorreu durante os períodos vegetativos estivais, nos anos de 1992, 1993 e 1994. Na cultura de tomate, foram capturadas duas espécies de parasitóides oófagos, Telenomus sp. (Hymenoptera: Scelionidae) e Trichogramma cordubensis (Hymenoptera: Trichogrammatidae), enquanto que, na beterraba apenas se observaram ovos de A. gamma parasitados pelo género Telenomus no primeiro ano em estudo. Ao comparar as percentagens de parasitismo por Telenomus sp. nas duas culturas, verificou-se que estas foram superiores na cultura do tomate. Nesta, a percentagem de parasitismo por Telenomus sp. foi significativamente superior à de T. cordubensis, inclusivamente, atingindo valores elevados nos dois primeiros anos (33% em 1992 e 50% em 1993).Este estudo foi co-financiado pela Universidade dos Açores, "Fundação Luso-Americana para o Desenvolvimento" e Secretaria Regional de Agricultura e Pescas

Ratos : bioindicadores da qualidade do ar

A secção Biologia é coordenada pelo Professor Universitário Armindo Rodrigues.[…]. Das 3 espécies, a mais infetada pela bactéria leptospira e o rato domestico (murganho). De acordo com dados do Manual de boas práticas de controlo de roedores para a Região Autónoma dos Açores, da autoria da Comissão de Gestão Integrada de Pragas - Roedores (2012), mais de 50% dos roedores das ilhas de S. Miguel e Terceira estão infetados pelas bactérias causadoras da leptospirose. Se juntarmos a esta realidade o facto de, devido ao seu pequeno tamanho, os ratos ocuparem frequentemente os mesmos locais que o Homem (comensais), deparamo-nos com uma situação altamente preocupante em termos de saúde. A elevada humidade relativa do meio ambiente nos Açores agrava ainda mais esta situação, uma vez que prolonga a viabilidade das bactérias na urina do rato, aumentando a probabilidade de transmissão ao Homem. Estes são alguns dos lados “lunares” dos ratos! Mas o grupo de investigação em saúde pública e ecotoxicologia (PHERG) do Departamento de Biologia da Universidade dos Açores tem explorado o lado “solar” destes pequenos mamíferos. Em 2006 este grupo de investigação decidiu testar os murganhos como espécie bioindicadora da qualidade do ambiente na ilha de S. Miguel, particularmente nas Furnas. O facto de se tratar de um mamífero, ser uma espécie abundante e amplamente distribuída, e ocupar os mesmos espaços que a população humana, indiciava que poderia reunir as condições necessárias para servir estes propósitos científicos e, por consequência, sociais. […].info:eu-repo/semantics/publishedVersio

Suitability as Medfly Ceratitis capitata (Diptera, Tephritidae) hosts, of seven fruit species growing on the island of São Miguel, Azores

Seven species of fruit were selected to study their suitability as hosts to Ceratitis capitata (Wiedemann). Suitability was determined by evaluating field infestation rates of different host-fruit and by studying the performance of C. capitata reared on these hosts. We sampled old regional cultivars of hot pepper (Capsicum annuum), loquat (Eriobotrya japonica), cattley guava (Psidium littorale), sweet orange (Citrus sinensis) and mandarin (Citrus reticulata); and two introduced fruit plants, feijoa (Feijoa sellowiana cultivar Sellwiana) and peach (Prunus persica cultivar Robidoux). Of the latter, except for mandarin, fruit contained larvae that pupated and yielded viable adults. In the case of mandarins, larvae were detected but none was able to pupate. The percentage of infested fruit was similar among peach, feijoa, sweet orange and hot pepper and, significantly higher than the other hosts (>60%). The highest mean number of pupae and adults per fruit was observed in peach (18.30 and 17.17, respectively) and the lowest in loquat (4.62 and 3.68, respectively). Host-fruit significantly influenced pupal weight, with heavier pupae (0.0124 g) observed in sweet orange. The shortest pupal development time (9.31 days) was observed in hot pepper, whereas the longest (11.99 days) was in feijoa. Adult emergence rates were generally high (>80%), except for sweet orange. Results showed the most suitable host-fruit for C. capitata was peach, followed by cattley guava and feijoa; although loquat and sweet orange were shown to be the less suitable hosts they seem to have an important role as alternative hosts between January and June, allowing the continuous development of C. capitata throughout the year

Radon Exposure and Human Health: What Happens in Volcanic Environments?

Volcanic activity can cause hazardous effects to the environment and the health of the exposed persons such as an increased risk for the development of several cancers. In geothermal areas, volcanic gases such as radon are continuously vented from the main crater, from fumarolic fields or diffused through soil. The continued long-term exposure to radon can enhance the risk of lung cancer being considered the leading cause of lung cancer following tobacco smoking. The chronic exposure to volcanogenic radon requires the development of biomonitoring methods that will assist in the evaluation of the effects of exposure to this genotoxic element. The Human Biomonitoring with the use of exfoliated buccal cells is minimally invasive, and the endpoints of the buccal micronucleus cytome (BMCyt) assay are the biomarkers of effect most recently used to measure genetic damage for the exposure to genotoxic and cytotoxic xenobiotics. The BMCyt assay has been used in a number of occupational studies, and positive results were detected as a consequence of exposure to pesticides, metals, and industrial chemicals that are suspected to cause cancer. Regarding the chronic exposure to volcanic environments, many studies revealed a rise in the numbers of MN in buccal exfoliated cells, indicating an increased risk for cancer. This chapter aims to cover the main health hazards and biomonitoring methods for populations chronically exposed to volcanic environments, allowing an estimate of health risks and to implement risk management measures regarding the exposure to certain compounds