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[EN] BACKGROUNDA new Beauveria bassiana-based attract and infect device (AID) to control Rhynchophorus ferrugineus Olivier (Coleoptera: Curculionidae) was developed. The virulence and persistence of the fungal formulation used in the AID were evaluated in the laboratory. Semi-field and field trials were carried out to validate the results and establish the potential of this device as a control tool. RESULTSIn laboratory conditions, a 50% lethal time (LT50) of 4.33 days was obtained when adults (7-10 days old) were exposed to the inoculation tunnel (IT) containing 1 x 10(10) conidia g(-1) in an oil-based fungal formulation. This formulation maintained conidium viability at 50% for up to 2 months. Moreover, when adults were exposed to 2.5-month field-aged ITs, mortality still reached 50% 40 days after exposure. In addition, no differences were observed between ITs aged in early spring and those aged in summer, suggesting that the fungal formulation is not strongly affected by environmental factors in Mediterranean basin conditions. Semi-field assays showed that the device allowed an easy transit of weevils through the IT, which were effectively attracted and infected. Using the AIDs in 4-ha plot field trials, a reduction of >50% in the percentage of infested sentinel palms was obtained. CONCLUSIONBased on the results obtained in terms of the efficacy and persistence of this new AID in the field and its potential in reducing R. ferrugineus populations and palm infestation, this device could become a key tool for the management of R. ferrugineus. (c) 2018 Society of Chemical Industry, We wish to thank Manuel Piquer, Juan Argente and Carlos Campos for their assistance with many parts of this work, Cuca Orero for providing the trial field at Sagunt, and Jose Sancho from Sansan Prodesing SL for providing prototype solutions for the infective trap. The research that has led to these results received funding from the 7th European Union Framework Programme with Grant Agreement no. FP7 KBBE 2011-5-289566 (PALM PROTECT).

The lethal effects of the benzoylphenyl urea diflubenzuron were assessed under laboratory conditions against one day old fourth (IV) Dociostaurus maroccanus (Thunberg) (Orthoptera: Acrididae: Gomphocerinae) instars. Following exposure by ingestion of a single dose applied to short pieces of wheat seedlings, nymphs were monitored for two moults until the adult stage. The obtained acute response gave an LD50 of 1.47 μg a.i./nymph. The male and female nymphs response to diflubenzuron did not show statistical significance but there was a narrow tolerance range within the female treated population. Analysis of the relative mortality in classes at individual dose rates showed that mortality occurring in the moult to V instar increased directly related to diflubenzuron dose rate. The duration of IV instar was significantly higher following treatments with all diflubenzuron doses, whereas the duration of the V instar did not show any clear differences between treated and control nymphs. The main sublethal effects on these adult females was a reduction of the number eggs per egg-pods, which could have major impacts on the evolution of D. maroccanus outbreaks and their management. Key words: Moroccan locust, locust control, lethal effects, sublethal effects, reproduction. VALUTAZIONI DI LABORATORIO SULLA TOSSICITÀ ACUTA E CRONICA DEL DIFLUBENZURON CONTRO NINFE DELLA CAVALLETTA MEDITERRANEA DociostAurus MAroccAnus (THUNBERG) Sono stati valutati mediante saggi di laboratorio gli effetti letali di benzoylphenyl urea diflubenzuron contro ninfe di Dociostaurus maroccanus (Thunberg) (Orthoptera: Acrididae: Gomphocerinae). Dosi singole sono state applicate su pezzetti di cariossidi di grano e, dopo l’ingestione, la vita delle ninfe è stata monitorata fino al raggiungimento dello stadio adulto. I dati ottenuti hanno evidenziato una DL50 di 1.47 μg a.i./ninfa. La risposta delle ninfe maschio e femmina al diflubenzuron non ha evidenziato alcun significato statistico anche se la popolazione delle femmine trattate ha mostrato una certa tolleranza. L’analisi della mortalità relativa ad ogni singola dose utilizzata ha evidenziato che la mortalità ottenuta nel passaggio al secondo stadio di ninfa aumentava in maniera direttamente proporzionale alla dose utilizzata. La durata del I stadio ninfale è stata significativamente maggiore dopo il trattamento con diflubenzuron a tutte le dosi, mentre la durate del II stadio ninfale non ha mostrato alcuna differenza tra ninfe trattate e non trattate. Il maggiore effetto subletale sulle femmine adulte è stato la riduzione del numero di uova che ha influenzato il successivo sviluppo della popolazione di D. maroccanus. Parole chiave: Dociostauro, controllo, effetti letali, effetti subletali, riproduzione., Entomologica, Vol 36 (2002)

Palm Protect es un proyecto del Séptimo Programa Marco de la U.E. que trata de desarrollar métodos fiables de detección, erradicación, control y contención de dos insectos invasores de las palmeras, el picudo rojo, Rhynchophorus ferrugineus y la mariposa, Paysandisia archon, ambos introducidos de forma accidental en Europa a través de material infestado. Las larvas de ambos insectos se comportan como taladros y se alimentan tanto del interior de la palmera, especialmente la palmera canaria y la palmera datilera, como de sus hojas. Transcurrido un tiempo desde la infestación, el daño se hace evidente, en ocasiones este es tan grave que suele conducir al colapso y muerte de la palmera, como es el caso de R. ferrugineus. Se estima que las pérdidas anuales producidas por ambas especies ascienden a varios millones de euros. Por lo que los métodos desarrollados en Palm Protect se emplearán en el origen, en el punto de entrada, en el tránsito y en el lugar a combatir dichas plagas.

Se ha evaluado el potencial insecticida de una cepa del hongo entomopatógeno Beauveria bassiana (Ascomycota: Clavicipitaceae) obtenida de una pupa de Rhynchophorus ferrugineus (Coleoptera: Curculionidae) infectada en estado natural. En condiciones de laboratorio, esta cepa presenta patogenicidad para todos los estados del desarrollo del picudo rojo, la virulencia en términos de CL50 es diferente para cada uno de los estados, sigue la cadencia: larvas de 4º estadio, huevos, adultos de cría y adultos de campo; los adultos tratados con conidios, fueron capaces de transmitir la enfermedad al sexo contrario, muestran disminución, al propio tiempo, de la fecundidad de hembras y la viabilidad de huevos. En ensayos de semicampo, utilizando Phoenix canariensis, se obtuvieron altas eficacias, tanto en pulverización como por pintado, que confirman el potencial de esta cepa para el control de R. ferrugineus.

Esta invención está relacionada con un hongo entomopatógeno de la especie Beauveria bassiana que es capaz de reducir el número de larvas vivas de Euzophera pinguis Haw presentes en plantas leñosas atacadas por dicho fitófago. Este hongo puede ser utilizado como agente de control biológico para proteger a las plantas leñosas frente a E. pinguis, siendo este sistema una alternativa biológica a los métodos actuales basados en el empleo de productos químicos para el control del fitófago.

Working Group “Insect Pathogens and Entomopathogenic Nematodes”. Preceedings of the 13th European Meeting “Biological Control in IPM Systems” at Innsbruck (Austria), 19 – 23 June, 2011.

5 páginas, 4 figuras.-- Trabajo presentado por el Working Group: "Integrated protection of Olive Crops" al Meeting de Bragança (Portugal) celebrado del 10 al 12 de Octubre de 2007., The objective of this study was to determine the persistence of the autochthonous Metarhizium anisopliae EAMa 01/58-Su isolate in the soil when applied beneath olive trees for controlling olive fly puparia and to elucidate its possible effect on non-target soil dwelling arthropod communities. For that, we selected 200 olives trees in an organic olive orchard at the province of Málaga(Spain) to be sprayed either with a 2.5 x·107 conidia m-2 suspension of the fungus on the ground beneath the tree canopy (100 trees) or with the blank formulation as controls (100 trees). Before fungal treatments, we selected 10 trees from the treated ones for evaluating both the possible presence of indigenous entomopathogenic fungi in the soil by using the Galleria Bait Method and the evolution of the conidial densities in the soil after spraying. The entomopathogenic fungus Beauveria bassiana (Balsamo) Vuill. was the most common species, being found in all the samples, while M. anisopliae was found only in one sample. After spraying the 100 treated and 100 control trees, soil samples beneath the 10 selected trees from the top 10 cm were taken to calculate the number of conidial forming units per gram of soil at 1, 7, 14, 28, 35, 42, 49, 56 and 63 days after treatment respectively. Our preliminary data indicate that the soil ecosystem favours the persistence of this autochthonous isolate, which could allow long term protection of the crop against olive fly puparia. In order to assess the possible effect of the fungal treatment on soil arthropod populations, 40 pitfall traps (7.5 cm diameter by 10 cm deep) placed beneath the tree canopy of randomly selected 20 treated and 20 controls trees, were sampled every two weeks. Our preliminary data indicate that formicidae species are the most abundant arthropods trapped, but no infected insects have been found in field as a result of the treatment to now.

The fungus Beauveria bassiana is a well recognised entomopathogen known to infect hundreds of host species from most of the insect orders. Therefore, the use of this fungus as a biological control agent against insect pests is very promising and several commercial products have already been developed. The natural occurrence of B. bassiana has been reported throughout Spain. Recently, its presence has been also verified in Portugal, specifically in the Trás-os-Montes region.

El desarrollo de hongos entomopatógenos para el control de plagas de insectos ha experimentado en los últimos años un considerable progreso. El empleo de estos agentes de control biológico presenta numerosas ventajas, seguridad para la salud humana y para la fauna útil, reducción de la presencia de residuos insecticidas en los alimentos e incremento de la biodiversidad del medio. Los hongos son únicos y sobresalientes entre los microorganismos entomopatógenos porque infectan a los hospedantes a través del tegumento, acción por contacto, lo que les confiere ventaja para el control de varios grupos de insectos fitófagos de gran relevancia en la agricultura mediterránea. Sin embargo, un empleo más eficiente y generalizado de estos agentes en el control depende en gran medida de la mejora de su velocidad de acción, reducción de los tiempos letales. Algunas cepas fúngicas secretan proteínas insecticidas durante el desarrollo de la infección, que se postulan entre las mejores dianas para la selección y mejora biotecnológica a efectos de control, así como una fuente inexplorada de nuevas moléculas insecticidas de origen natural. El Grupo AGR 163 “Entomología Agrícola” de la Universidad de Córdoba dispone de una colección de más de 300 aislados autóctonos de los ascomicetos mitospóricos Beauveria bassiana y Metarhizium anisopliae procedentes de suelos de la Península Ibérica y archipiélagos Canario y Balear, que es una buena base para la selección de aislados que produzcan in vitro proteínas insecticidas, para (1) estudiar su desarrollo como micoinsecticidas; (2) determinar si la secreción de estas proteínas ocurre también in vivo y su función como determinantes de virulencia; (3) evaluar el posible empleo de estas proteínas como nuevas moléculas insecticidas de origen natural; (4) desarrollar marcadores moleculares que permitan identificar los aislados más importantes y detectar los genes que codifican para esta proteínas, para la posible mejora genética

Due to the problems caused by the use of chemical insecticides for humans and environment alternative pest control methods are an important topic of research. The use of microbial insecticides especially fungal agents are an attractive and promising alternative for biological control of insect pests. The aim of this work was to identify naturally occurring entomophatogenic fungi on the olive moth, Prays oleae Bern., in the northeast of Portugal, as first step to select biological control agent again this olive pest. The experimental work was carried out during 2007 in the three generation of the insect (phyllophagous, anthophagous and carpophagous generation). In each generation P. oleae larvae and pupae were collected in different groves and were put in glass vials in a climatic chamber with a photoperiod of 12h light:12h dark, 22ºC (light): 16ºC (dark) and 60% relative humidity, until emergency of the adults. From dead larvae, fungi were isolated on PDA plates and incubated at room temperature. Pure cultures were morphological and molecularly identified based on the ITS region of the rDNA. From the identified species Beauveria bassiana Vuill. and Cordyceps sinensis (Berk.) Sacc. were the most promising being B. bassiana the most abundant one. This work was partially financed by the project INTERREG IIIA