Abstract: Objective: To compare the efficacy of three modern larvicides with the organophosphate temephos for control of Aedes aegypti in water tanks in Chiapas. Materials and methods: Trials were performed to compare the efficacy of pyriproxyfen, novaluron, two formulations of spinosad (granules and tablets) and temephos in oviposition traps and domestic water tanks. Results: Pyriproxyfen and temephos provided 2-3 weeks of complete control of larvae in oviposition traps, whereas spinosad granules and novaluron provided 7-12 weeks of control. Treatment of water tanks resulted in a significant reduction in oviposition by Ae. aegypt in houses (p<0.001). Higher numbers of larvae were present in temephos and pyriproxyfen-treated water tanks compared to novaluron and spinosad tablet treatments during most of the study. Conclusion: Spinosad formulations and novaluron were effective larvicides in this region. The poor performance of temephos may be indicative of reduced susceptibility in Ae. aegypti populations in Chiapas.

Resumen: Objetivo: Comparar la eficacia de tres larvicidas modernos para el control de Aedes aegypti en tanques de agua doméstica en Chiapas. Material y métodos: Se comparó la eficacia de piriproxifeno, novalurón, dos formulaciones de spinosad (gránulos y tabletas) y temefos en ovitrampas y tanques domésticos de agua. Resultados: El piriproxifeno y el temefos proporcionaron de 2 a 3 semanas de control de larvas en ovitrampas, mientras que los gránulos de spinosad y novaluron proporcionaron de 7 a12 semanas. Los tanques de agua tratados produjeron una reducción significativa en la oviposición por Ae. aegypti en las casas (p<0.001). Se encontró gran cantidad de larvas en los tanques tratados con temefos y piriproxifeno en comparación con los tratados con novaluron y tabletas de spinosad durante la mayor parte del estudio. Conclusión: Las formulaciones de spinosad en tabletas y novaluron fueron larvicidas efectivos en esta región. El bajo desempeño de temefos puede indicar una susceptibilidad reducida en poblaciones de Ae. aegypti en Chiapas.

This article focuses on a topic, that is captured in a question that Richard Dawkins raised in 1993: 'What makes you think Theology is a subject?' My view is that this question is a symptom of how Theology is under attack from many quarters today - from the fearful believers who see it as a threat to their faith, to the secularists who see it as a threat to truth. Foremost among the opponents is Richard Dawkins. Outraged by a donation to Cambridge for the study of theology, he contrasts the usefulness of science with the uselessness of Theology. The question though, is: What is Theology? In this chapter, I draw a distinction between Confessional Theology and Critical Theology. By Confessional Theology I mean the affirmation of an exclusive point of reference by which all other claims to authority and knowledge are judged. Thus Christians 'confess Jesus Christ is Lord', and Confessional Theology is the rational articulation of the Christian Faith from within the circle of Faith - the convictions, experiences, and hopes grounded in the story of Jesus and characterized by commitment and involvement. However, there are ways in which both scientists and theologians, and the two types of Theology, can go wrong.

Los invernaderos de Almería, España, representan la extensión más grande de cultivos cubiertos en Europa. Larvas de Spodoptera exigua son una plaga importante en muchos de estos cultivos y han desarrollado resistencia a la mayoría de insecticidas registrados en Europa. El nucleopoliedrovirus de S. exigua (SeMNPV; Baculoviridae) es un patógeno autóctono de este insecto. La persistencia del virus es alta en el suelo de todos los cultivos aunque su incidencia es mayor en primavera y verano. Se han podido identificar hasta nueve variantes genotípicas del virus en esta zona. En términos de patogenicidad, virulencia y producción de los poliedros o cuerpos de inclusión (OBs, por sus siglas en inglés), las mezclas de ciertos genotipos tienen mayor potencial insecticida que los genotipos puros. La producción de OBs in vivo puede ser hasta tres veces mayor en las larvas tratadas con análogos de la hormona juvenil. Compuestos derivados del estilbeno tienen una actividad sinérgica con los OBs en condiciones de laboratorio y reducen la dosis letal del virus en campo. La eficacia en campo de una formulación sencilla fue mejor que la que ofrecen los tratamientos de varios insecticidas de síntesis. Actualmente el virus se produce masivamente en una planta comercial y se ha iniciado el proceso de registro del producto para su utilización en cultivos de pimiento dulce en los invernaderos de Almería. Los resultados de estas investigaciones pueden facilitar el desarrollo del SeMNPV como insecticida biológico en otras partes del mundo, incluyendo América Latina.

The greenhouses of Almeria, Spain, represent the largest extension of covered crops in Europe. Larvae of Spodoptera exigua are an important pest in many of these crops and have developed resistance to the majority of insecticides registered in Europe. The nucleopolyhedrovirus (SeMNPV; Baculoviridae) of S. exigua is a native pathogen of this insect. The persistence of the virus is high in the soil of all crops, although its incidence is highest in spring and summer. As many as nine genotypic variants of the virus have been identified in this zone. In terms of pathogenicity, virulence and production of progeny virus occlusion bodies (OBs), mixtures of certain genotypes have greater insecticidal potential than pure genotypes. Production of OBs in vivo can be up to three-fold greater in larvae treated with juvenile hormone analogues. Compounds derived from stilbene have a synergistic activity with OBs in the laboratory and reduce the lethal dosis in the field. The field efficacy of a simple formulation was greater than that offered by treatments of various synthetic insecticides. The virus is currently being mass-produced in a commercial production facility and the process of registration has begun for its use in sweet pepper crops in Almerian greenhouses. The results of these investigations should facilitate the development of SeMNPV as a biological insecticide in other parts of the world, including Latin America.

Invertebrate iridescent viruses (IIVs) are icosahedral DNA viruses that infect invertebrates, mainly insects and terrestrial isopods, in damp and aquatic habitats. Exhaustive searches of databases resulted in the identification of 79 articles reporting 108 invertebrate species naturally infected by confirmed or putative iridoviruses. Of these, 103 (95%) were arthropods and the remainder were molluscs, an annelid worm and a nematode. Nine species were from marine habitats. Of the 99 non-marine species, 49 were from terrestrial habitats and 50 were aquatic, especially the aquatic stages of Diptera (44 species). The abundance of records from species of Aedes,Ochlerotatus and Psorophora contrasts markedly with a paucity of records from species of Anopheles,Culex and Culiseta. Records from terrestrial isopods are numerous (19 species), although the diversity of IIVs that infect them is mostly unstudied. IIV infections have been reported from every continent, except Antarctica, but there are few records from Africa, southern Asia and Latin America. Most reports describe patent IIV infections as rare whereas inapparent (covert) infection may be common in certain species. The relationship between particle size and iridescent colour of the host is found to be consistent with optical theory in the great majority of cases. Only 24 reported IIVs from insect hosts have partial characterization data and only two have been subjected to complete genome sequencing. I show that the rate of publication on IIVs has slowed from 1990 to the present, and I draw a number of conclusions and suggestions from the host list and make recommendations for future research efforts.

Los virus iridiscentes de invertebrados (VIIs) son virus icosaedrales de ADN que infectan a invertebrados, principalmente insectos e isópodos terrestres en hábitats húmedos y acuáticos. Búsquedas extensivas de bases de datos resultaron en la identificación de 79 artículos científicos, los cuales reportaron 108 especies de invertebrados infectados naturalmente por iridovirus. De estos, 103 (95%) fueron artrópodos y los otros fueron moluscos, un anélido y un nematodo. Nueve especies fueron de hábitats marinos. De las 99 especies no marinas, 49 fueron terrestres y 50 fueron acuáticas, especialmente los estadios acuáticos de dípteros (44 especies). La abundancia de infecciones en especies de Aedes,Ochlerotatus y Psorophora se contrasta marcadamente con la escasez de casos en especies de Anopheles,Culex y Culiseta. Reportes de infecciones de los isópodos terrestres son numerosos (19 especies), aunque la diversidad de los VII que los infectan es desconocida. Se han reportado infecciones por VIIs de todos los continentes, excepto Antártica, pero se notan pocos ejemplos de África, Asia y Latinoamérica. La mayoría de los artículos señala que las infecciones patentes son poco comunes, mientras que las infecciones enmascaradas (subletales) pueden ser comunes en algunas especies. La relación entre el tamaño de la partícula y el color iridiscente concuerda con la teoría óptica en casi todos los casos. Veinticuatro de los VIIs de insectos han sido caracterizados parcialmente y solo dos de éstos han sido secuenciados completamente. Demuestro que el ritmo de publicación sobre los VIIs ha disminuido en los últimos 15 años, señalo varias conclusiones y sugerencias de la lista de especies de huéspedes y presento algunas recomendaciones para la investigación futura con este grupo de patógenos.

Os efeitos da estrutura etária e da densidade do hospedeiro na transmissão horizontal de um baculovírus foram investigados em laboratório, utilizando-se populações de lagarta do repolho, Mamestra brassicae L. (Lepidoptera: Noctuidae). Os insetos foram mantidos a três combinações de ínstares e três densidades populacionais em recipientes fechados contendo larvas infectadas. As larvas foram observadas diariamente e o número de mortes e o tempo letal foram registrados. Os níveis de mortalidade viral foram marginalmente superiores em recipientes contendo hospedeiros sob maior densidade populacional. As larvas apresentaram um risco de infecção aparentemente maior quando combinações de instares mais avançados foram usadas. Os níveis de mortalidade de larvas mais velhas foram maiores que as de larvas mais jovens. As médias de tempo letal das populaç ões larvais foram maiores para larvas mais jovens, observando-se um declínio mais acentuado na curva de sobrevivência das larvas em estágio mais adiantado de desenvolvimento.

The effects of stage structure and host density on baculovirus horizontal transmission were examined in the laboratory using larvae of the cabbage moth, Mamestra brassicae L. (Lepidoptera: Noctuidae). Insects were reared at three instar combinations and three host densities in closed containers with infected larvae. Insects were observed daily and the number of deaths and time to death were recorded. Levels of virus mortality were marginally higher in the containers where a higher density of hosts was introduced. Larvae appeared to have a greater risk of infection when late instar combinations were used. Final levels of mortality of older larvae were significantly higher than those of younger larvae. Mean times to death of larval populations were longer for larvae at earlier instar combinations, with a faster decrease in survivorship of older larvae over time.