CURRENT TRENDS IN BIOLOGICAL CONTROL First Meeting of TEAM. Palma of Mallorca. 7-8 th April 2008.

Transcription

1 CURRENT TRENDS IN BIOLOGICAL CONTROL First Meeting of TEAM. Palma of Mallorca. 7-8 th April Successful acclimatization of the ovo-pupal parasitoid Fopius arisanus in Reunion island for the biological control of the peach fruit fly, Bactrocera zonata SERGE QUILICI 1, PASCAL ROUSSE 1, JEAN-PHILIPPE DEGUINE, CHRISTOPHE SIMIAND 1, ANTOINE FRANCK 1, FREDERIC GOURDON 1, THOMAS MANGINE 2 and ERNEST HARRIS 2 1 CIRAD Réunion, UMR PVBMT, Pôle de Protection des Plantes, 7 chemin de l IRAT, Saint-Pierre, France. 2 USDA-ARS Pacific Basin Agricultural Research Centre, 2727 Woodland Drive, Honolulu, HI 96822, USA. quilici@cirad.fr The Peach fruit fly, Bactrocera zonata, was first detected in 1991 in Reunion Island where it established itself from 2000 on. Its competitive abilities soon allowed it to become the dominant species in the lowland areas where it partially displaced some already established Ceratitis species. The host range of this polyphagous species currently correspond to some 12 fruit species with economic damage particularly important on mango and guava. The introduction of the ovo-pupal parasitoid Fopius arisanus was achieved in December 2003, through a partnership between CIRAD and USDA Hawaii. Biological and behavioural studies showed that this parasitoid was able to develop on several tephritid of economic importance present in the island, though the preferred host was B. zonata. Releases were carried out in in various sites of the island, with a total of adults released. In 2006, a few months after the last releases occurred, the parasitoid was recorded in various areas of the island, on different host-fruits. A survey conducted on Indian almond (Terminalia catappa), on which B. zonata is the dominant species, showed that the level of parasitism on this host-fruit could at times reach 70-80%. The successful acclimatization of this parasitoid aims at decreasing the populations of the Peach fruit fly in reservoir areas where huge populations used to develop in the absence of an effective biocontrol agent. Future studies will focus on precising the impact of this promising parasitoid in different ecological conditions and on different host fruits. ORAL SUBMISSION Key: 1578 Symposium: Current Trends in the Biological Control of Fruit Flies

2 Laboratory evaluation of parasitism of Bactrocera invadens and five Ceratitis species by the opiine parasitoids Fopius arisanus and Diachasmimorpha longicaudata SAMIRA A. MOHAMED, SUNDAY EKESI and RACHID HANNA International Centre of Insect Physiology and Ecology (ICIPE), , Nairobi, Kenya. Fopius arisanus (Sonan) (Hymenopera: Braconidae) and Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) are solitary koinobiont endoparasitoids of fruit flies. The two species were introduced for testing and eventual release against the recently described and exotic species Bactrocera invadens Drew, Tsuruta & White (Diptera: Tephritidae) in Africa. Laboratory experiments were conducted to assess the parasitoids host preference and host acceptability for oviposition in B. invadens and five indigenous fruit fly species - the Medfly Ceratitis capitata (Wiedemann), the mango fruit fly C. cosyra (Walker), the Natal fruit fly C. rosa Karsch, C. fasciventris (Bezzi), and C. anonae Graham. The physiological suitability of these fruit fly hosts for the development of both parasitoid species was also evaluated. Females of the two parasitoid species visited all host eggs patches, but F. arisanus showed a stronger preference for B. invadens, which was also most accepted for oviposition by this parasitoid. On the other hand, C. cosyra was most accepted by D. longicaudata. Successful development of parasitoid progeny varied greatly across hosts for both parasitoids species tested, with B. invadens and C. capitata yielding respectively the highest number of parasitoid progeny of F. arisanus and D. longicaudata. Ceratitis fasciventris did not yield any F. arisanus progeny. Sex ratio (proportion of female offspring) of F. arisanus was female-biased in all host species that produced parasitoid progeny. On the other hand sex ratio of D. longicaudata was male-biased on all five Ceratitis species and female-biased on B. invadens. The majority of F. arisanus eggs oviposited in C. rosa and C. fasciventris failed to hatch mainly due to encapsulation, or died as larvae. Similarly, nearly all D. longicaudata eggs laid in C. rosa, C. fasciventris and C. anonae, and about one third of eggs oviposited in B. invadens were encapsulated and failed to hatch. The results are discussed in the light of the potential use of F. arisanus and D. longicaudata for classical biological control of B. invadens in Africa. ORAL SUBMISSION Key: 1731 Symposium: Current Trends in the Biological Control of Fruit Flies

3 Exploration for natural enemies of Bactrocera invadens in Sri Lanka for classical biological of the pest in Africa M.K. BILLAH, S. EKESI, R. HANNA, G. GOERGEN and K.A.N.P. BANDARA International Centre of Insect Physiology and Ecology (ICIPE), 00100, Nairobi, Kenya. Following the invasion of Bactrocera invadens (Diptera: Tephritidae) in Africa, evaluation of native larval braconid (Psyttalia) and eulophid (Tetrastichus) parasitoids either ended in low acceptance and poor development or in egg encapsulation, suggesting the non-suitability of the local parasitoids in biological control of the pest. To find more effective natural enemies, three exploratory activities were conducted in the putative aboriginal home (Sri Lanka) of the pest to survey the fruit fly complex and associated natural enemies and to identify effective potential biological control candidates. Methyl Eugenol traps were deployed at 64 sites in 30 localities across all agro-ecological zones in 7 of the 9 provinces of the Island for field monitoring in addition to collection of major cultivated and wild host fruits from the trapping sites. Trap collections revealed that B. kandiensis, B. zonata, B. invadens and B. correcta were the four dominant species across all agro-ecological zones, while B. paraverbascifoliae was the predominant species in the highland areas. Although B. invadens was found in all ecozones, it was more abundant in the low and intermediate altitudes compared with the highlands, thus re-affirming results from Kenya that it might be a lowland species. A total of kg of fruits were bulkprocessed from 39 species in 16 plant families, with B. kandiensis, B. invadens and B. cucurbitae being the most dominant. Infestation levels ranged from pupae/g of sampled fruits. Eight parasitoid species (5 larval, 2 pupal and 1 egg) were recorded with percent parasitism ranging from 0 and 24.9%. In addition, two coleopteran predators and one mite species were encountered. Colonies of B. invadens, B. zonata and B. kandiensis have been established and biological studies of three parasitoid species (Fopius arisanus, Diachasmimorpha longicaudata, Psyttalia fletcheri) are underway. ORAL SUBMISSION Key: 1733 Symposium: Current Trends in the Biological Control of Fruit Flies

4 Potential for Biological control of Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) by parasitoids in Spanish Mediterranean areas. F. BEITIA 1, M. PÉREZ-HINAREJOS 1, E. GARZÓN 1, S. SANTIAGO 1, V. FALCÓ 1 and P. CASTAÑERA 2 1 Centro de Protección Vegetal y Biotecnología, Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. Moncada-Náquera km. 4.5, Moncada, Valencia, Spain. 2 Departamento Biología de Plantas, Centro de Investigaciones Biológicas (CIB), Consejo Superior de Investigaciones Científicas (CSIC), C/ Ramiro de Maetzu, 9, 28040, Madrid, Spain. fbeitia@ivia.es The Mediterranean fruit fly, Ceratitis capitata (Wiedemann), has been considered by the Spanish citrus sector as the main problem in citrus production, due to direct yield losses and to quarantine restrictions. Recently, it has been detected resistance to malathion, an essential insecticide for the control of this pest, in Spanish field populations of C. capitata. This reinforces the search for ecologically sound control strategies, such as biological control by using exotic parasitoids and by conservation of the native ones. Here, we will focus on classical biological control with the introduction of exotic parasitoids and the search for native parasitoids in the Mediterranean area. Two exotic parasitoids were imported by IVIA from Hawaii: The larval-pupal parasitoid Diachasmimorpha tryoni (Cameron) and the egg-pupal parasitoid Fopius arisanus (Sonan) (Hymenoptera: Braconidae). Laboratory and semi-field studies have been performed with both species to assess the potential of both parasitoids to control C. capitata. In spite of the lasting presence of C. capitata in the Mediterranean area, there are not references of indigenous parasitoids in Spain. Two species of pteromalids, parasitoids of pupae in the Valencia region, were found when searching for native parasitoids: Spalangia cameroni Perkins and Pachycrepoideus vindemmiae (Rondani). However, further studies are needed to assess their role in the control of this major citrus pest, as they are not specific parasitoids of C. capitata. ORAL SUBMISSION Key: 1828 Symposium: Current Trends in the Biological Control of Fruit Flies

5 Effects of Oecophylla longinoda in controlling mango fruit flies in Benin JEAN-FRANÇOIS VAYSSIERES and PAUL VAN MELE IITA-CIRAD / Biological Control Center for Africa, 08 B.P. 0932, Cotonou, Benin. j.vayssieres@cgiar.org In northern Benin, the mango fruit fly targets are the species of economic significance which comprises Ceratitis cosyra (Walker), C. quinaria (Bezzi), C. silvestrii (Bezzi) and Bactrocera invadens Drew et al., a new invasive species in West Africa. Experiments were carried out in northern Benin during two consecutive mango seasons. During the first one, six mango plantations were sampled at 2-week intervals for fruit fly damage from early April to late May, Mean damage ranged from 1 to 24% with the weaver ant Oecophylla longinoda (Latreille) according four abundance classes (high abundance, medium abundance, low abundance, absent). Exclusion experiments conducted in 2006 with Eldon, Kent and Gouverneur cultivars confirmed that at high ant abundancy levels, Oecophylla longinoda significantly reduced with large effect Ceratitis spp and B. invadens infestations as well. A lot of work was done on another weaver ant species, Oecophylla smaragdina, in Asian and Australian areas indicating that this ant species is an efficient biocontrol agent of mango pests. Although fruit fly control methods are still at an experimental stage in West Africa, farmers who accepted or tolerated weaver ants in their orchard were rewarded by significantly better fruit quality and higher yield as well. Conservation biological control with predatory ants such as Oecophylla longinoda in high-value tree crops (mangos, citrus, cashew) has great potential for African farmers. We hope to sensitize them more and more about this economic type of biological control through participatory approach. On-going studies in Benin aim at acquiring a better understanding of the ecology of weaver ants and at setting up a regional research and development program to optimize the full benefits of this valuable generalist predator in West African orchards. Actually its large distribution from dry savannas to humid coastal forests made it particularly suitable for smallholder farmers in sub-saharan Africa. ORAL SUBMISSION Key: 1869 Symposium: Current Trends in the Biological Control of Fruit Flies

6 Susceptibility of Rhagoletis cerasi to entomopathogenic fungi CLAUDIA DANIEL 1,2 1 Research Institute of Organic Agriculture (FiBL), Ackerstrasse, 5070 Frick, Switzerland. 2 TU München, Wissenschaftszentrum Weihenstephan, Fachgebiet Obstbau, Freising, Germany. claudia.daniel@fibl.org The effects of six fungus strains (Deuteromycotina: Hyphomycetes) on the mortality of different life stages of the European cherry fruit fly, Rhagoletis cerasi Loew (Diptera: Tephritidae), were assessed in a series of laboratory experiments. All fungus strains were able to cause mycosis to larvae and adults of R. cerasi. However, virulence varied considerably among the strains. Effects on L3-larvae were negligible. In contrary, adults were highly susceptible to fungus infection. Beauveria bassiana and Paecilomyces fumosoroseus caused 90 to 100% mortality and had a strong influence on fecundity. Metarhizium anisopliae also showed reliable effects. The pathogenicity of Paecilomyces farinosus was low. Higher conidia concentrations lead to higher mortality, whereas B. bassiana was most efficient at low concentrations. Young flies showed lower mortality rates than older flies but, sublethal effects on eclosion rate off eggs were greater in young than in older flies. Key: 1561 Panel: Current Trends in Biological Control of Fruit Flies

7 Practical experience in using entomopathogenic nematodes to control the European Cherry Fruit Fly, Rhagoletis cerasi L. (Diptera, Tephritidae) ANNETTE HERZ, KIRSTEN KOEPPLER, HEIDRUN VOGT, PETER KATZ and ARNE PETERS Federal Biological Research Centre for Agriculture and Forestry, D-69221, Dossenheim, Baden-Württemberg, Germany. The cherry fruit fly, Rhagoletis cerasi L., is the major pest of sweet cherries in Europe. Currently, no efficient control method is available and there is the risk of increasing population densities of this pest. Entomopathogenic nematodes (EPN) caused high mortality of last instar maggots, when entering the soil for pupation, under laboratory and field conditions. Field applications of these biocontrol agents during consecutive years should test their efficacy to reduce pest densities under practical conditions. One to several applications of a commercially available product based on Steinernema feltiae (application rate to EPN/m²) against pupating larvae in summer did not result in a reduction in the emergence rate of adult flies in the following spring in comparison to untreated plots. Infection rates of exposed larvae did not exceed 50%, thus being much lower than under laboratory conditions. Accompanying field observations were made to evaluate the degree of natural mortality of the cherry fruit fly during the pupation phase in order to decide if the application of nematodes could substantially contribute to control this pest. Whereas natural mortality factors reduced the cherry fruit fly population from the period between larvae leaving the fruit until hatching of adults in the following year by 95%, the application of nematodes did not contribute significantly to pest regulation, due to their weak efficacy under practical conditions. Key: 1717 Panel: Current Trends in Biological Control of Fruit Flies

8 Influence of environmental temperature on the parasitoidism behaviour of Diachasmimorpha longicaudata and Opius concolor (Hymenoptera, Braconidae) R. FERNÁNDEZ-SÁNCHEZ 1, J. A. MUÑOZ ORELLANA 2, S. MARAÑÓN JIMÉNEZ 1, J. P. ROS AMADOR 3 and M. CAMPOS ARANDA 1 1 Estación Experimental del Zaidín CSIC, Profesor Albareda, nº 1, 18008, Granada, Spain 2 Universidad de Granada, OTRI, Complejo Administrativo Triunfo, Pab. 1; Cuesta del Hospicio s/n, 18071, Granada, Spain. 3 Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), Crta. de la Coruña, km. 7.5, 28040, Madrid, Spain. rfernand@ujaen.es Mediterranean fruit fly, Ceratitis capitata (Diptera, Tephritidae) is oligophagous damaging the fruits from more than 300 plant species and varieties. So, this species is considered one of the most important pests in tropical and warm areas. Because of this, knowing how this pest can be controlled by parasitoids is a relevant research approach. As any other insect, parasitoid insects can be influenced by abiotic factors such as temperature. The aim of this work was to study the influence of temperature on two species of larval endoparasitic wasps, Diachasmimorpha longicaudata and Opius concolor, both included in the Braconidae family. Third-instar larvae of medfly were offered to isolated pairs of each parasitoid species during 24 hours. Experiments were conducted in an environmental controlled chamber, at a set temperature (20, 25 or 30 ºC). After exposition time, host larvae were maintained at 24 ºC till imago emergence from pupal case. Experimental results showed that D. longicaudata was not significantly affected by temperature, while O. concolor had higher parasitoidism rates at 30 ºC. However, at 20 ºC D. longicaudata showed higher parasitoidism rates than O. concolor. On the other hand, trials suggest the O. concolor offsping sex ratio is biased toward females with increasing temperature. Key: 1718 Panel: Current Trends in Biological Control of Fruit Flies

9 Characterization of Bacillus thuringiensis strain collections from Spain and Morocco ecosystems and evaluation of their insecticidal activity against Ceratitis capitata (Diptera: Tephritidae) JOSÉ CRISTIAN VIDAL QUIST 1, HOUDA ABOUSSAID 2,3, KHALID OUFDOU 2, SAID EL MESSOUSSI 3, PEDRO CASTAÑERA DOMÍNGUEZ 1 and JOEL GONZÁLEZ- CABRERA 1 1 Unidad Asociada de Entomología IVIA-CIB CSIC, Instituto Valenciano de Investigaciones Agrarias (IVIA), Ctra. Moncada-Náquera km 4,5, 46113, Moncada, Valencia, España. 2 Equipe de Microbiologie et Toxicologie Environnementales, Laboratoire de Biologie et Biotechnologie des Microorganisme and 3 Laboratoire de Modélisation moléculaire et Ecophysiologie, Université Cadi Ayyad, Faculté des Sciences-Semlalia, BP 2390, Marrakech, 40000, MAROC. joel.gonzalez@ivia.es The Mediterranean fruit fly is one of the most devastating fruit pests worldwide, current control is mainly based on synthetic insecticides. The environmental impacts they produce, in addition to development of resistance justify the need to implement sustainable control alternatives. Bacillus thuringiensis Berliner (Bt) based products lead bioinsecticides market. They have been proven to be active against insects of many orders, including dipterans. However, no active strain against Ceratitis capitata Wiedemann has been described to date. In this study, two collections of 376 and 50 Bt strains have been established from samples collected in Valencian Community (Spain) and Agadir-Marrakech (Morocco), respectively. These collections were characterized by means of phase-contrast microscopy, SDS-PAGE and PCR to detect 20 groups of cry and cyt genes codifying for toxins active against lepidopteran, coleopteran, dipteran and nematodes species. PCR analysis identified 10 combinations among selected genes, being more abundant those effective against lepidopterans, present in more than half of the strains. Protein electrophoresis revealed 57 different profiles that, in many cases, could be correlated with bacterial morphology and gene composition. Toxicity bioassays against C. capitata were carried out for all strains in the collection, recording maximum mortalities of %. Additionally, bioassays with isolates from other collections (509 strains) were performed, showing similar mortality levels. Key: 1748 Panel: Current Trends in Biological Control of Fruit Flies

10 Parasitism of Bactrocera oleae (Diptera; Tephritidae) by Psyttalia (Opius) concolor (Hymenoptera; Braconidae) in the Balearic Islands (Spain) M. MIQUEL 1, M.A. MIRANDA 1, J. TERRASSA 1, E. MARTÍNEZ 1, M. MONERRIS 1, A. JUAN 2 and J. GOMILA 3 1 Laboratory of Zoology, University of the Balearic Islands, Ctra. Valldemossa km. 7.5, Palma de Mallorca, Spain. 2 Dirección Gral. de Recursos Hídricos, Govern Balear, Palma de Mallorca, Spain. 3 Àrea de Sanitat Vegetal. Conselleria d Agricultura i Pesca. Palma de Mallorca. margamiquel@hotmail.com Psyttalia concolor is an hymenopteran braconidae that was introduced in Spain in the early 70s for the control of the olive fruit fly Bactrocera oleae. It has been always considered that P. concolor was poorly adapted to temperate zones, as for example the Balearics. In this study, we demonstrate the high rate of parasitism of B. oleae by P. concolor in Mallorca (Balearic Islands). Two organic farming olive orchards (A and B) were selected in the municipality of Montuiri (central area of the island). A sample of 250 olive fruits was weekly collected from each of the orchards. The olives were kept under laboratory conditions until emergence of B. oleae pupae. These were placed in Petri dishes in the same conditions until the emergence of adults either B. oleae or P. concolor. In addition, red sticky spheres and yellow sticky panel traps were placed in both orchards for monitoring of adults of P. concolor. The study was carried out from August to December Results showed a high presence of adults of P. concolor in the field. In total, 141 specimens were captured in orchard A and 614 in orchard B. The red spheres captured more individuals of the parasitoid when compared with the yellow panels. In regards to the percentage of parasitism of B. oleae pupae by P. concolor, the results were similar in the both orchards, 22.4% in orchard A and 23.4 % in orchard B. The high rate of parasitism by P. concolor in organic farming olive orchards is mainly due to the ban of using synthetic insecticides. This clearly allows to reach high levels of auxiliary fauna populations. Finally, the use of red spheres should not be recommended when populations of the parasitoid are present in the orchard. Key: 1870 Panel: Current Trends in the Biological Control of Fruit Flies

11 Floral strips for conservation biocontrol in organic olive groves FRANCOIS WARLOP GRAB, Avignon cx 9, France. Olive fly, only pest limiting a successful transition to organic farming, has a certain number of parasitoids and predators. Their efficacy and action has however been limited for years by an intensive soil cultivation to limit competition for water or nutrients, even in watered orchards. We aim at showing that floral strips with a specific, mediterranean and functional flora, can be maintained in olive groves, and be efficient in attracting beneficials and increasing spontanenous biocontrol rates. A network has been built since 2004, involving 15 olive growers. Flora and fauna are under investigation, to assess the capacity of strips to be established under limited water availability, the competition with spontaneous species, the diversity in various insect taxa... Key: 1689 Panel: Current Trends in the Biological Control of Fruit Flies