Thesis (MSc)--University of Stellenbosch, 2003. / ENGLISH ABSTRACT: The Mediterranean fruit fly (Medfly), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is well-known as a destructive pest of fruit worldwide. Various control methods have been used against this insect. The sterile insect technique (SIT) is used as an important and successful technological method for controlling or eradicating this pest in many countries. A key factor to successfully apply SIT is dependent on the availability of efficient and economical rearing methods. Artificial insect diets with low cost bulking agents have been of interest to many researchers. The present study investigated the use of locally available maize meal as a bulking agent in such diets. Maize meal is used for human consumption (in South Africa) and contains small amounts of protein. This makes the reduction of imported torula yeast as an ingredient of the diet and source of protein possible, thereby reducing the cost of the diet. The larval development of the Medfly reared on artificial diets was studied in small and large-scale tests. The effect of the diets on larval production was evaluated using pupal recovery, pupal weight, flight ability, sex ratio, fecundity and egg fertility. The results of the small-scale tests showed that the diet containing maize meal could be used to produce Medfly more economically than the standard Krige diet used by the ARC Infruitec-Nietvoorbij Research Institute at Stellenbosch. However, in large-scale tests the ingredients quantities of the diets used were not the same as those of small scale-tests. The cost of the modified larval diet was not reduced in large-scale tests. This was ascribed to the number of eggs used in the tests to produce one million of fruit flies. The maize meal with reduced number of eggs require more diet to produce one million flies therefore, making it more expensive and less viable. When similar amounts of eggs were used, the diet appears to be a suitable alternative as the result obtained was almost similar to those of the Krige diet. / AFRIKAANSE OPSOMMING: Die Mediterreens vrugtevlieg ("Medfly"), Ceratitis capitata (Wiedemann) (Diptera: Tephritidae) is wêreldwyd 'n skadelike plaag. Die steriele insek tegniek (SIT) het in baie lande 'n belangrike en suksesvolle manier geword om die plaag te beheer en uit te roei. Die belangrikste voorvereiste vir die suksesvolle toepassing van SIT is die beskikbaarheid van doeltreffende en ekonomiese teelmetodes. Meeste navorsers is geïntereseerd in kunsmatige diëte met 'n goedkoop vulstof. Hierdie studie is ontwerp om die gebruik van plaaslik beskikbare mieliemeel as vulstof te ondersoek. In Suid-Afrika word dit vir menslike gebruik aangewend en bevat klein hoeveelhede proteïene wat 'n vermindering van die ingevoerde torula gis moontlik kan maak, en sodoende die koste van die dieët kan verminder. Die ontwikkeling van Medfly larwes op kunsmatige diëte is bestudeer In kleinskaalse en grootskaalse eksperimente. Die invloed van die diëte op larwale produksie is evalueer deur gebruik te maak van van papie-ontwikkeling, papie-gewig, vliegvermoë, geslagsverhouding, volwasse voortplantingsvermoë en eiervrugbaarheid. Die resultate van die kleinskaalse toetse het aangetoon dat die mieliemeel dieët gebruik kan word om Medfly meer ekonomies as met die standaard Krige dieët, wat in die ARC Infruitec-Nietvoorbij navorsings instituut by Stellenbosch gebruik word, te teel. By die grootskaalse toetse was die koste nie laer nie. Dit word toegeskryf aan die aantal eiers wat gebruik is om 'n miljoen vlieë te produseer. Die mieliemeel dieët met 'n verminderde aantal eiers benodig meer dieët om 'n miljoen vlieë te produseer, wat dit duurder en minder lewensvatbaar maak. Wanneer soortgelyke hoeveelhede eiers gebruik was, het dit geblyk dat die dieët 'n opsie is, want die resultaat was soortgelyk aan dié van die Krige dieët.

Thesis (MSc)--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The Mediterranean fruit fly (medfly), Ceratitis capitata, is a highly invasive species throughout the world and considered as one of the most successful agricultural and economical pests. The increase of global trade in fruit and human travel combined with the biology of the medfly has allowed the species to spread from its proposed Afrotropical origin, to a number of locations throughout the world. In the Western Cape various control strategies have been implemented to control medfly populations, including insecticides and more environmentally-friendly techniques such as the Sterile Insect Technique (SIT). In order to be effective, however, an SIT program requires some knowledge of the population structure and the movement of individuals between pest-occupied sites. The identification of sites from which re-invasion is most likely to occur and knowledge regarding the primary routes through which pests are likely to re-establish are critical to ensure successful SIT programmes. To provide this important information to SIT and area-wide pest control programs in South Africa, sampling at two different spatial scales (regional- and fine-scale) in South Africa was undertaken. Regional scale sampling was done at 13 locations in the Western Cape and fine scale sampling was done at 13 locations within the Ceres-valley. All individuals were genotyped at 11 polymorphic microsatellite markers and selected individuals from the regional scale were sequenced for the mitochondrial gene COI. Our results show that populations at regional- and fine-scale in the Western Cape are characterized by high levels of genetic diversity (HEregional = 0.805; HEfine = 0.803). Little or weak population differentiation was detected at the regional- and fine-scales, suggesting overall high levels of gene flow among sampling locations. These findings were supported by coalescent based methods indicating sufficient levels of gene flow to prevent population differentiation between neighbouring (200m) and distant (350km) populations. However, natural dispersal in C. capitata has been shown to rarely exceed 10 km. As such, high levels of gene flow between distant populations are more likely the result of humanmediated dispersal, linked to the movement of fresh produce within South Africa. This high level of gene flow has important implications for pest management practices, as my results suggests that area-wide pest management should be undertaken at a regional scale, rather than on a farm or valley scale. My results are placed within a management framework, and I argue for more stringent control when fruit are transported within South Africa. Of particular interest for future studies is the investigation of gene flow at broader spatial scales (i.e. the whole of South Africa) and a comparison of the genetic diversity, population differentiation and gene flow patterns of C. capitata with that of Ceratitis rosa will be important to establish a successful pest management strategy in South Africa. / AFRIKAANSE OPSOMMING: Die Mediterreense vrugtevlieg (medvlieg), Ceratitis capitata, is ‘n indringerspesie wêreldwyd en word beskou as een van die mees suksesvolle ekonomiese en landbou peste. Die medvlieg het ‘n Afrotropiese oorsprong, maar die toename in wêreldwye handel en reis, gekombineer met die biologie van die medvlieg het gelei tot die verspreiding van die spesie na ‘n groot aantal bestemmings regoor die wêreld. Die Wes-Kaap provinsie van Suid-Afrika implementeer tans verskeie strategieë om medvlieg bevolkings te beheer. Hierdie strategieë sluit in die gebruik van plaagdoders sowel as meer omgewingsvriendelike tegnieke soos die Steriele Insektegniek (SIT). Om ‘n effektiewe SIT program te implementeer vereis basiese kennis ten opsigte van die genetiese struktuur van die bevolking sowel as van die beweging van individue tussen verskillende pesvoorkomsgebiede. Die identifisering van areas van waar herkolonisering mees waarskynlik kan plaasvind en kennis in verband met die primêre roetes waardeur pes spesies hervestig, is van kritiese belang om ‘n suksesvolle SIT program te verseker. Medvlieg individue is op twee verskillende ruimtelike skale (streeks- en plaaslike-skaal) versamel om die nodige inligting aan SIT en area-wye pes beheer programme in Suid-Afrika te verskaf. Streeks-skaal individue is by 13 lokaliteite regoor die Wes-Kaap versamel en plaaslike-skaal individue by 13 lokaliteite in die Ceres-vallei. Alle versamelde individue is vir 11 polimorfiese mikrosatelliet merkers gegenotipeer en DNS volgordebepaling van geselekteerde individue vanuit die streek-skaal is gedoen vir die mitochondriale geen COI. My resultate toon dat bevolkings op beide skale gekarakteriseer word deur hoë vlakke van genetiese diversiteit (HEstreeks = 0.805; HEplaaslik = 0.803) en geen of swak bevolkings differensiasie. Hierdie resultate dui daarop dat daar hoë vlakke van geenvloei tussen bevolkings is. Hierdie bevindinge word verder ondersteun deur metodes gebaseer op die statistiese eienskappe van die genealogiese verhouding tussen allele onder sekere mutasie en demografiese modelle, wat voldoende vlakke van geenvloei aandui tussen nabye (200m) sowel as verafgeleë (350km) bevolkings om bevolkings differensiasie te verhoed. Natuurlike beweging in C. capitata is egter selde meer as 10 km, sodanig kan die hoë vlakke van geenvloei toegeskryf word aan die verspreiding van individue met menslike hulp, spesifiek in die vervoer van varsprodukte in Suid-Afrika. Hierdie hoë vlak van geenvloei het verreikende implikasies vir pes beheer praktyke, omdat my resultate voorstel dat area-wye pes beheer onderneem moet word op ‘n streeks-skaal eerder as op ‘n plaas-tot-plaas of vallei wye area. Ek plaas my resultate in ‘n bestuursraamwerk, waarin ek streng beheer van vrugtevervoer in Suid-Afrika beklemtoon. Verdere navorsing moet fokus op die ondersoek van geenvloei op ‘n landswye skaal (hele Suid-Afrika) in C. capitata, sowel as die vergelyking van die genetiese diversiteit, bevolkings differensiasie en geenvloei patrone van C. capitata met die van Ceratitis rosa om ‘n suksesvolle pes beheer strategie vir Suid-Afrika te formuleer.

Os experimentos de campo foram realizados em 2002 e 2003 em três pomares no município de Monte Alegre do Sul, SP, representados por uma coleção de linhagens de goiabeiras (janeiro a abril), uma coleção de cultivares de nespereiras (agosto a setembro) e uma coleção de cultivares de pessegueiros (setembro a outubro). Nos ensaios de infestação, foram utilizadas três linhagens de goiaba (Guanabara, L7P28 e 252), duas cultivares de nêspera (Precoce Campinas e a Precoce 264-54) e três cultivares de pêssego (Aurora 2, Dourado 1 e Régis). Para a determinação do período de infestação, aplicou-se o processo de ensacamento e desensacamento quinzenal e semanal da goiaba e nêspera, respectivamente, e apenas o ensacamento semanal no pêssego. Cada experimento iniciou-se com os frutos ainda no início de seu desenvolvimento (frutos verdes). Para o processo de desensacamento, no início dos experimentos foram ensacados 500 e 400 frutos de goiaba e nêspera, respectivamente. Em cada ensaio, desde o início (frutos verdes pequenos) até a completa maturação, quinzenalmente (goiaba) ou semanalmente (nêspera e pêssego) foi ensacada/desensacada uma amostra de 30 frutos, os comprimentos e diâmetro eram mensurados e retirava-se amostras para realização das análises físico-químicas em laboratório. Após o completo amadurecimento, os frutos foram colhidos e levados ao laboratório, onde foram pesados, medidos os diâmetro e comprimento e depois acondicionados individualmente em copos plásticos com areia+vermiculita até aproximadamente a metade e cobertos com "voil" preso com fita elástica. Para o conhecimento da flutuação populacional das moscas, foram instaladas três armadilhas modelo McPhail com torula (atraente alimentar) em cada pomar, de janeiro/2002 a janeiro/2004. Das moscas-das-frutas originadas dos frutos, foram identificadas cinco espécies de tefritídeos e oito espécies de lonqueídeos. Os parasitóides emergidos foram das famílias Braconidae e Figitidae, representados por cinco espécies de cada uma. Ceratitis capitata apresentou comportamento sazonal com picos populacionais durante o segundo semestre. Verificou-se que a população de moscas-das-frutas (Anastrepha spp. e lonqueídeos) se mantém na área dos pomares (goiaba, nêspera e pêssego) durante o ano todo. Os três hospedeiros sofreram o ataque de moscas-das-frutas nos seus primeiros estádios de desenvolvimento, a partir de 2 cm de diâmetro. Ao longo do desenvolvimento, em todos os hospedeiros (goiaba, nêspera e pêssego), a infestação foi ascendente, apresentando as maiores elevações no final do amadurecimento. Os parâmetros físicos (tamanho, firmeza, brix e cor) mostraram-se mais confiáveis para o prognóstico da suscetibilidade do fruto ao ataque das moscas-das-frutas do que os parâmetros químicos (pH, acidez e umidade) para todos os hospedeiros. Os aspectos ecológicos da infestação dos frutos pela moscas-das-frutas e a relação tritrófica (parasitóide/mosca/fruto) foram discutidos. / Field experiments were conducted in three orchards in Monte Alegre do Sul, SP, each containing either a collection of strains of peach (September to October), guava (January to April) or loquat (August to September), during 2002 and 2003. Three strains of guava (Guanabara, L7P28 and 252), two of loquat (Precoce Campinas and Precoce 264-54) and three of peach (Aurora 2, Dourado 1 and Régis) were used for infestation assessment. Guava and loquat fruits were bagged and unbagged biweekly and weekly, respectively, for the assessment of the infestation period and only weekly for the peach. In all cases, fruits were bagged at the beginning of their development, while still green. A sample of 30 bagged fruits were unbagged weekly (loquat and peach) or biweekly (guava) until fruits were completely ripe, from a total of 500 (guava) and 400 (loquat) fruits. Fruits were measured and a sample was taken for physicochemical analysis. Fruits were harvested once they were ripe, taken to the laboratory, weighted and measured. They were placed into plastic cups half-filled with sand and covered with a fine fabric to allow for field-collected fly development. Three McPhail traps containing Torula yeast (food attractant) were hung from January/2002 to January/2004 to assess the population fluctuation of fruit flies in each orchard. Five tephritids and eight lonchaeids species emerged from field-collected fruits maintained in the lab. Five species each of braconid and figitid fruit fly parasitoids were also observed emerging from these fruits. Ceratitis capitata showed a sazonal behavior with population density peaking at the second semester. It was also observed that Anastrepha spp. and lonchaeids remained in the orchards throughout the year. All three host fruits larger than 2 cm in diameter were infested by fruit flies at the early stages of development. Fruit infestation increased in all orchards as fruit development occurred with the highest infestation level observed at the end of the ripening. Physical parameters, such as size, firmness, brix and color were more reliable in estimating fruit susceptibility to fruit-flies than the chemical parameters evaluated (pH, acidity and humidity) for all three host fruits. The ecological aspects of the infestation of fruits by fruit flies and the tritrophic interactions (parasitoid/fruit fly/fruit) were discussed.

Os experimentos de campo foram realizados em 2002 e 2003 em três pomares no município de Monte Alegre do Sul, SP, representados por uma coleção de linhagens de goiabeiras (janeiro a abril), uma coleção de cultivares de nespereiras (agosto a setembro) e uma coleção de cultivares de pessegueiros (setembro a outubro). Nos ensaios de infestação, foram utilizadas três linhagens de goiaba (Guanabara, L7P28 e 252), duas cultivares de nêspera (Precoce Campinas e a Precoce 264-54) e três cultivares de pêssego (Aurora 2, Dourado 1 e Régis). Para a determinação do período de infestação, aplicou-se o processo de ensacamento e desensacamento quinzenal e semanal da goiaba e nêspera, respectivamente, e apenas o ensacamento semanal no pêssego. Cada experimento iniciou-se com os frutos ainda no início de seu desenvolvimento (frutos verdes). Para o processo de desensacamento, no início dos experimentos foram ensacados 500 e 400 frutos de goiaba e nêspera, respectivamente. Em cada ensaio, desde o início (frutos verdes pequenos) até a completa maturação, quinzenalmente (goiaba) ou semanalmente (nêspera e pêssego) foi ensacada/desensacada uma amostra de 30 frutos, os comprimentos e diâmetro eram mensurados e retirava-se amostras para realização das análises físico-químicas em laboratório. Após o completo amadurecimento, os frutos foram colhidos e levados ao laboratório, onde foram pesados, medidos os diâmetro e comprimento e depois acondicionados individualmente em copos plásticos com areia+vermiculita até aproximadamente a metade e cobertos com “voil” preso com fita elástica. Para o conhecimento da flutuação populacional das moscas, foram instaladas três armadilhas modelo McPhail com torula (atraente alimentar) em cada pomar, de janeiro/2002 a janeiro/2004. Das moscas-das-frutas originadas dos frutos, foram identificadas cinco espécies de tefritídeos e oito espécies de lonqueídeos. Os parasitóides emergidos foram das famílias Braconidae e Figitidae, representados por cinco espécies de cada uma. Ceratitis capitata apresentou comportamento sazonal com picos populacionais durante o segundo semestre. Verificou-se que a população de moscas-das-frutas (Anastrepha spp. e lonqueídeos) se mantém na área dos pomares (goiaba, nêspera e pêssego) durante o ano todo. Os três hospedeiros sofreram o ataque de moscas-das-frutas nos seus primeiros estádios de desenvolvimento, a partir de 2 cm de diâmetro. Ao longo do desenvolvimento, em todos os hospedeiros (goiaba, nêspera e pêssego), a infestação foi ascendente, apresentando as maiores elevações no final do amadurecimento. Os parâmetros físicos (tamanho, firmeza, brix e cor) mostraram-se mais confiáveis para o prognóstico da suscetibilidade do fruto ao ataque das moscas-das-frutas do que os parâmetros químicos (pH, acidez e umidade) para todos os hospedeiros. Os aspectos ecológicos da infestação dos frutos pela moscas-das-frutas e a relação tritrófica (parasitóide/mosca/fruto) foram discutidos. / Field experiments were conducted in three orchards in Monte Alegre do Sul, SP, each containing either a collection of strains of peach (September to October), guava (January to April) or loquat (August to September), during 2002 and 2003. Three strains of guava (Guanabara, L7P28 and 252), two of loquat (Precoce Campinas and Precoce 264-54) and three of peach (Aurora 2, Dourado 1 and Régis) were used for infestation assessment. Guava and loquat fruits were bagged and unbagged biweekly and weekly, respectively, for the assessment of the infestation period and only weekly for the peach. In all cases, fruits were bagged at the beginning of their development, while still green. A sample of 30 bagged fruits were unbagged weekly (loquat and peach) or biweekly (guava) until fruits were completely ripe, from a total of 500 (guava) and 400 (loquat) fruits. Fruits were measured and a sample was taken for physicochemical analysis. Fruits were harvested once they were ripe, taken to the laboratory, weighted and measured. They were placed into plastic cups half-filled with sand and covered with a fine fabric to allow for field-collected fly development. Three McPhail traps containing Torula yeast (food attractant) were hung from January/2002 to January/2004 to assess the population fluctuation of fruit flies in each orchard. Five tephritids and eight lonchaeids species emerged from field-collected fruits maintained in the lab. Five species each of braconid and figitid fruit fly parasitoids were also observed emerging from these fruits. Ceratitis capitata showed a sazonal behavior with population density peaking at the second semester. It was also observed that Anastrepha spp. and lonchaeids remained in the orchards throughout the year. All three host fruits larger than 2 cm in diameter were infested by fruit flies at the early stages of development. Fruit infestation increased in all orchards as fruit development occurred with the highest infestation level observed at the end of the ripening. Physical parameters, such as size, firmness, brix and color were more reliable in estimating fruit susceptibility to fruit-flies than the chemical parameters evaluated (pH, acidity and humidity) for all three host fruits. The ecological aspects of the infestation of fruits by fruit flies and the tritrophic interactions (parasitoid/fruit fly/fruit) were discussed.

Thesis (MScAgric)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: Botrytis bunch rot of grape is caused by Botrytis cinerea Pers. :Fr. Conidia of the pathogen, which is dispersed by wind, water droplets and by insects, can penetrate the intact grape berry cuticle, but disease expression occurs only under predisposing conditions. Since relatively high infection rates often occur in vineyards, predisposing factors must play a fundamental role in primary infection and subsequent disease occurrence. Insects can play a very important role in this regard by depositing inocula at wound sites during feeding and by providing fresh wounds during their oviposition and feeding activities. The aim of this study was (i) to determine the potential of the Mediterranean fruit fly to transfer B. cinerea and other bunch and fruit rot fungi in natura, (ii) to investigate the transport, deposition and subsequent disease expression on grape berries in vitro, and (iii) to investigate fruit fly activities and the nature of deposited conidia and mycelia of B. cinerea by aid of digital photography and epifluorescence microscopy, respectively. Two Sensus fruit fly traps containing the para-pheromone, Capilure, were installed in orchards and five neighboring vineyards on four farms in the Stellenbosch region. Ceratitis fruit flies were collected weekly, identified and counted to determine the fluctuations in fruit fly population. Following field collection, the fruit flies were plated on Kerssies' B. cinerea selective medium and the number of flies yielding the pathogen was recorded. Two fruit fly species, C. capitata and C. rosa, were captured during the study period. Ceratitis rosa numbers comprised only 1% of the total number of fruit flies captured. Ceratitis capitata numbers, and the percentage B. cinerea contaminated flies generally increased after harvest in the different orchards and vineyards. Following harvest, the percentage flies yielding B. cinerea was higher in vineyards compared to orchards. Furthermore, in each vineyard an increase in percentage B. cinerea contaminated fruit flies was preceded by a corresponding increase in its neighboring orchard. The levels of both Penicillium and Alternaria contaminated fruit flies stayed high throughout the investigation period, especially after harvest of the orchard cultivars. Low incidence of Aspergillus, Mucor and Rhizopus spp. were recorded on C. capitata. These findings suggest that the Mediterranean fruit fly may play an important role in the dispersal of inocula of fungi associated with postharvest decay from early-maturing stone fruit orchards to mid- and late-maturing wine grape vineyards, and in disease induction under conditions unfavourable for natural infection. Three experiments were conducted to determine the potential of fruit flies in provoking B. cinerea decay. In the first experiment, transport of conidia and disease expression were investigated on rachis segments bearing unwounded berries only. In the second experiment, the effect of wounding on disease expression was investigated. In the third experiment, the effect of inoculum type (mycelia and conidia) on transportation and disease expression was investigated on rachis segments bearing unwounded berries, and on segments with wounded berries. The table grape cultivar, Dauphine, and the wine grape cultivar, Shiraz, were used at véraison, two weeks before harvest and harvest, and the transport studies were conducted in ethanol-disinfected perspex cages. Disease expression was studied in dry (~56% RH), ethanol-disinfected perspex chambers incubated at 22°C. The isolations from berries revealed that the flies deposited, without preference, high amounts of B. cinerea at various positions on the grape berry's surface. The freezing studies showed that the deposited conidia germinated and penetrated the berry skin at various positions. However, B. cinerea developed more often at the pedicel end than on the cheek or style end, which indicated a peculiar interaction between B. cinerea, the fruit fly and host tissue at this part of the berry. This phenomenon was substantiated by the finding that B. cinerea also developed more often at the pedicel end of berries that were not frozen. Further evidence for this interaction was found on intact berries exposed to flies that carried mycelia after feeding on berries without sporulating colonies of the pathogen, but showing symptoms of slippery skin. Significantly more decay developed on wounded berries compared to the unwounded berries and more so at the wound site. In addition, female fruit flies were responsible for significantly more decay development than male fruit flies. The study thus proved that the Mediterranean fruit fly can promote B. cinerea disease development under conditions unfavorable to natural infection. The activities of the Mediterranean fruit fly, Ceratitis capitata, on grape berries were monitored by aid of digital photography. In addition, the deposition of conidia and mycelia of Botrytis cinerea at three sites (pedicel end, cheek and style end) on the grape berry, germination of the fungal structures after dry (±56% RH) and moist (±93% RH) incubation and wounds inflicted during ovipositioning were examined with an epifluorescence microscope. The observations revealed that the fruit fly's activities were generally restricted to the grape berry. They visited the grape berry cheek more often, but visitations to the pedicel end of berries increased substantially from véraison to harvest, indicating the possibility of nutrient leakages at this site. Microscopy revealed that the flies deposited conidia singular, in feeding packages and in faecal excrements on the berry surface. The conidia in feeding packages were ensheathed by salivical fluids and occurred in clusters of 10 to 50 conidia. An average of 60% of the conidia in feeding packages germinated under dry conditions (±56% RH). Conidia that passed through the intestinal tract of the fruit fly and that were deposited in faecal excrements were deformed and low in viability. These conidia did not occur in cluster format, but were proportionally spread with the faeces on the surface of the grape berry. Conidia that were deposited singular and in faecal excrements did not germinate unless incubated under moist conditions (± 93% RH). Wounds inflicted by female fruit flies during ovipositioning were most frequently observed on the cheek. This predisposition to B. cinerea infection of grape berries by the activities of fruit flies, suggested an important role for the flies in the initiation of Botrytis bunch rot epidemics in vineyards. / AFRIKAANSE OPSOMMING: DIE ROL VAN DIE MEDITERREENSE VRUGTEVLIEG, CERATITIS CAPITATA, IN BOTRYTIS CINEREA TROSVERROTTING VAN DRUIWE Botrytis-trosverrotting van druiwe word deur Botrytis cinerea Pers. :Fr. veroorsaak. Konidia van die patogeen wat deur wind, waterdruppels en insekte versprei word, kan die intakte druiweskil binnedring, maar siekte-uitdrukking vind slegs onder spesiale omstandighede plaas. Aangesien relatief hoë infeksie vlakke algemeen in wingerde voorkom, moet predisponerende faktore 'n fundamentele rol in die primêre infeksie, en die daaruit voortspruitende siektetoestand speel. Insekte kan 'n baie belangrike bydrae lewer deur inokuia tydens voeding by wonde te deponeer. Nuwe wonde kan ook tydens oviposisionering en voeding ontstaan. Die doel van hierdie studie was om (i) die potensiaal van die Mediterreense vrugtevlieg om B. cinerea en ander tros- en vrugverrottingswamme in natura oor te dra, te bepaal; om (ii) die verspreiding, deponering en daaropvolgende siekteuitdrukking op druiwekorrels in vitro te ondersoek; en om (iii) die aktiwiteite en aard van die gedeponeerde konidia en miselia met behulp van digitale fotografie sowel as epifluoressensiemikroskopie waar te neem. Twee Sensus-vrugtelokvalle met die paraferomoon, Capilure, IS In vrugteboorde en aangrensende wingerde in die Stellenbosch-omgewing aangebring. Ceratitis-vrugtevlieë is weekliks versamel, geïdentifiseer en getel om fluktuasies in die vrugtevliegpopulasie te bepaal. Na die veldversameling is die vrugtevlieë op Kerssies se B. cinerea-selektiewe medium uitgeplaat. Gedurende die studie is twee spesies vrugtevlieë, C. capitata en C. rosa, gevang. Na oesstyd het die aantal Ceratitis-vrugtevlieë en die persentasie vrugtevlieë, besmet met B. cinerea, in die verskillende boorde en wingerde toegeneem. Na oestyd was die persentasie vrugtevlieë wat B. cinerea gedra het, hoër in die wingerde as in die boorde. Elke toename in die persentasie B. cinerea-besmette vrugtevlieë in 'n wingerd is voorafgegaan deur 'n ooreenkomstige toename in die aangrensende vrugteboord. Die aantal vrugtevlieë besmet met Penicillium en Alternaria spp. het tydens die navorsingstydperk deurgaans hoog gebly, veral nadat die vrugteboord-kultivars geoes is. Die voorkoms van Aspergillus-, Mucor- en Rhizopus spp. op Ceratitis-vrugtevlieë was deurgaans laag. Hierdie bevinding wys daarop dat vrugtevlieë 'n belangrike rol speel in die verspreiding van swarninokula, wat met na-oes verrotting geassosieer word, van vroegrypwordende steenvrugteboorde na mid- en laatrypwordende wyndruifwingerde. Drie eksperimente is in vitro onderneem om vrugtevlieë se potensiaal om B. cinereaverrotting te veroorsaak te bepaal. In die eerste eksperiment is ragi met slegs ongewonde korrels gebruik om die oordrag van konidia en siekte-ontwikkeling te ondersoek. In die tweede eksperiment is die effek van verwonding op siekte-ontwikkeling ondersoek. In die derde eksperiment is die effek van inokulumtipe (miselia en konidia) op verspreiding en siekte-ontwikkeling ondersoek deur ragis-segmente met gewonde korrels sowel as ragissegmente met ongeskonde korrels te gebruik. Die tafeldruif-kultivar Dauphine en die wyndruif-kultivar Shiraz, by kleurbreuk, twee weke voor oes en by oestyd, is in die eksperimente gebruik. Die oordragstudies is in etanol-ontsmette perspex-hokke uitgevoer. Siekte-ontwikkeling is bestudeer in droeë (±56% RH), etanol-ontsmette perspex-kamers en geinkubeer by 22°C. By ondersoek is gevind dat vlieë, sonder voorkeur, groot hoeveelhede B. cinerea op verskeie dele op die druiwekorrel-oppervlak deponeer. Bevriesingstudies het aangetoon dat die gedeponeerde konidia op verskeie dele van die korrelontkiem en die skil binnedring. Botrytis cinerea het egter meer dikwels by die korrelsteelkant as by die stempelkant, of op die wang, ontwikkel. Hierdie bevinding het 'n eiesoortige interaksie tussen B. cinerea, die vrugtevlieg en gasheerweefsel by die korrelsteelkant van die korrel aangetoon. Die verskynsel is gestaaf deur die bevinding dat B. cinerea ook meer dikwels by die korrelsteelkant van die korrels wat nie gevries is nie, ontwikkel het. Verdere bewys van hierdie interaksie is gevind by ongeskonde korrels wat aan die vlieë wat miselia gedra het blootgestel is. Die siekte het beduidend meer dikwels op gewonde as ongewonde korrels en verder aansienlik meer dikwels op die wondoppervlakte ontwikkel. Dit was ook duidelik dat vroulike vrugtevlieë baie meer vir verrotting verantwoordelik was as manlike vrugtevlieë. Die studie bewys dus dat Mediterreense vrugtevlieë die ontwikkeling van B. cinerea kan bevorder in omstandighede wat ongunstig is vir natuurlike infeksie. Die aktiwiteite van die Mediterreense vrugtevlieg C. capitata op die druiwekorrels is met behulp van digitale fotografie waargeneem. Verder is die deponering van konidia en miselia van B. cinerea op die verskillende dele (korrelsteelkant, wang en stempelkant) van die korrel, ontkieming van die swamstrukture na droeë (±56% RH) en nat (±93% RH) inkubasie en wonde wat tydens oviposisionering veroorsaak is, met epifluoressensie-mikroskopie ondersoek. Die waarnemings het onthul dat die vrugtevlieg se aktiwiteite gewoonlik tot die druiwekorrel beperk is. Hulle het korrelwange meer dikwels besoek. Besoek aan die korrelsteelkant het aansienlik toegeneem van kleurbreuk tot oestyd, wat op die moontlikheid van voedingstof-lekkasie by die deel aandui. Mikroskoopstudies het aangedui dat vlieë konidia enkel, in voedingspakkies en in fekale uitskeidings op die korreloppervlakte deponeer. Die konidia in die voedingspakkies is deur speekselvloeistof omhul en het in groepe van 10 tot 50 konidia voorgekom. Gemiddeld 60% van die konidia in voedingspakkies het in droeë omstandighede (±56% RH) ontkiem. Konidia wat deur die spysverteringskanaal van die vrugtevlieg gegaan het en in die fekale ekskresie gedeponeer is, was misvorm en het lae lewensvatbaarheid gehad. Laasgenoemde konidia was nie in groepe gedeponeer nie, maar is proporsioneel met die feces op die oppervlak van die druiwekorrel versprei. Konidia wat enkel en in feces gedeponeer is, het nie ontkiem nie, tensy toestande vogtig (±56% RH) was. Wonde wat deur die vroulike vrugtevlieë tydens oviposisionering veroorsaak is, is meer dikwels op die wang van die korrelopgemerk. Hierdie predisposisie van druiwekorrels tot B. cinerea-infeksie, meegebring deur die aktiwiteit van die vrugtevlieg, dui daarop dat die rol wat die vrugtevlieg in die inisiëring van Botrytis trosverrottingepidemies in wingerde speel, van beduidende belang is.

The genetic pathways influencing alcohol abuse and dependence are poorly characterized. Many critical discoveries about the interactions between ethanol-related behaviors and genetics have been made in the fruit fly Drosophila melanogaster. Coupling the statistical power of model organism studies to human association studies bolsters the analytical efficacy of these genomic approaches. A variety of behavioral assays are available for assessing behavioral responses to ethanol in Drosophila. However, we find our previously described eRING assay is influenced by the commonly used transgenic marker mini-white. We developed a Simple Sedation Assay (SSA) that is insensitive to the effects of white and mini-white. In SSAs, expression of endogenous wild-type white was not necessary for normal responses to ethanol. Neither expression nor RNAi-mediated knockdown of the transgenic mini-white influenced the effects of ethanol in flies. Critically, mini-white expression did not affect the phenotypes of flies with known alterations in ethanol sensitivity. Also, loss of function mutations in Clic show decreased sensitivity to ethanol in both eRING assays (as previously reported) and SSAs. Therefore, we explored the role of the known Clic interactors, TGF-β and ryanodine receptors. These studies were inconclusive but do not exclude the need for future work. Finally, using bioinformatic tools we constructed a mutli-species network of genes predicted to interact with Clic. Our RNAi screen against the Clic network serves as an important proof-of-concept and holds great potential for uncovering important therapeutic targets for alcohol use disorders.

A família Tephritidae congrega várias espécies de moscas-das-frutas que utilizam frutos como substrato alimentar no estágio larval, adquirindo o status de inseto-praga quando esses frutos são de valor comercial. O gênero Anastrepha é endêmico do Continente Americano e compreende cerca de 212 espécies descritas, das quais 109 ocorrem no Brasil. A espécie nominal Anastrepha fraterculus representa um complexo de espécies crípticas e se encontra distribuída pela Região Neotropical e sul dos Estados Unidos. No Brasil, através do estudo de diversas características biológicas e do marcador molecular ITS-1 (espaçador ribossômico nuclear), identificou-se a existência de três espécies crípticas no complexo fraterculus, a Anastrepha sp.1 affinis fraterculus, A. sp.2 aff. fraterculus e A. sp.3 aff. fraterculus. Marcadores gênicos presentes no DNA mitocondrial, como o gene cytochrome oxidase I (COI), são ferramentas amplamente utilizadas em análises filogenéticas, pois esta molécula apresenta características distintas do DNA nuclear, como o fato de possuir herança predominantemente materna, apresentar ausência ou baixíssima taxa de recombinação na maioria dos táxons, além de altas taxas mutacionais. Estas características possibilitam a obtenção de dados importantes na interpretação das relações entre as espécies. Amostras do complexo fraterculus (A. sp.1, A. sp.2, A. sp.3) de 14 localidades (média de 5 indivíduos / localidade) no sudeste do Brasil, uma amostra de A sp.4 do Equador e dois grupos externos (A. grandis e A. striata) foram utilizados. Fragmentos de 1139bp do gene COI foram amplificados e sequenciados, 45 haplótipos foram identificados: 30 em A. sp.1, 5 em A. sp.2 e 17 em A. sp.3. A distância média entre as espécies foi de 0,021 e o Fst médio foi 0,347 indicando estruturação populacional muito alta e pequena distância entre os haplótipos, que não apresentaram diferenças fixadas entre as espécies. Os testes de desvio de neutralidade apresentaram valores significativamente negativos. Os testes de seleção evidenciaram a atuação de seleção purificadora com baixos valores de Ka/Ks e significância no Z-teste de seleção. A análise filogenética mostrou fortes evidências de introgressão e não separou as diferentes entidades em clados distintos. Houve a formação de dois ramos principais, um constituído quase que exclusivamente por amostras de A. sp.1, e apenas duas amostras de A. sp.3, e outro que reuniu todas as espécies do complexo. Os dois principais grupos de haplótipos também foram visualizados na rede de haplótipos que mostrou indícios de expansão populacional. Quando somado ao estudo sequências depositadas em bancos de dados por outros autores, a espécie nominal A. fraterculus apresentou em sua distribuição 5 grupos de haplótipos mitocondriais. Dois deles ocorrem no Brasil, um com amostras do México e Costa Rica, um na Guatemala e Venezuela (baixa latitude) e um com indivíduos da Colômbia e Venezuela (alta latitude), sendo que os grupos Brasileiros também reuniram amostras da Argentina e do Equador. Assim, as sequências de COI não permitem a caracterização das entidades do complexo fraterculus apesar de indicar a estruturação populacional e a hipótese mais provável é a de que tenha havido introgressão da molécula mitocondrial entre as espécies do complexo com posterior expansão / The Tephritidae family comprises fruit flies species whose larvae feed and develop in fruits, many of which are commercial varieties and thus the species assume economic significance. Anastrepha genus is distributed throughout the Neotropical region and Southern United States. Analyses of biological characteristics and of the internal transcribed spacer (ITS-1) of the nuclear ribosomal DNA allowed the characterization of three cryptic species of the fraterculus complex in Brazil: Anastrepha sp.1 affinis fraterculus, Anastrepha sp.2 aff. fraterculus and Anastrepha sp.3 aff. fraterculus. Mitochondrial markers as gene cytochrome oxidase I (COI) are largely used in phylogenetic analyses because they have maternal inheritance, none or low recombination and high mutation rates compared to the nuclear DNA. Hence, analyses of the complex based in this marker will offer a divergent perspective from nuclear DNA for inferences on the evolutive relationships between different species. Samples from the fraterculus complex (A. sp.1, A. sp.2, A. sp.3) from 15 localities (average of 5 individuals/ locality) in southeastern Brazil, one sample of A. sp.4 from Ecuador and two outgroups (A. grandis and A. striata) were employed and COI sequences of 1139bp were amplified and analyzed. We identified 45 haplotypes: 30 in A. sp.1, 5 in A.sp.2 and 17 in A. sp.3. The mean distance between the haplotypes was 0.021 and mean Fst 0.347, indicating high population structure and low mitochondrial distance. The neutrality tests had significantly neutral values. The selection tests revealed the action of purifying selection with low values of Ka/Ks and significance in the Z-test selection. Phylogenetic analysis showed strong evidences of introgression and did not separate the various entities in distinct clades grouping the three species in a single branch; there was also the formation of another main branch formed almost exclusively by strains of A. sp.1 and only two samples of A. sp.3. The two main groups of haplotypes were also seen in the haplotype network that showed evidence of population expansion. The analysis of the philogenetic tree based on mitochondrial COI showed strong evidence for introgression. No fixed differences between species were found though mtDNA marker shows a lot of polymorphism. When added sequences deposited in databases by other authors the nominal species A. fraterculus presented in its distribution five groups of mitochondrial haplotypes, two of them in Brazil, one with samples from Mexico and Costa Rica, one in Guatemala and Venezuela and one with individuals from Colombia. The Brazilian groups also collected samples from Argentina and Ecuador. Therefore, the COI sequences do not allow the characterization of the entities of the fraterculus complex, although structure among the species is shown. The most likely hypothesis is that introgression has happened in the mitochondrial molecule among the species with further expansion

A assimetria de cinco estruturas corporais da mosca-das-frutas Ceratitis capitata foi analisada para uma avaliação se poderiam ser utilizadas como bioindicadores. As análises foram feitas em amostras de uma população natural e de uma população de laboratório. Adicionalmente, em amostras obtidas da população de laboratório, os índices de assimetria foram avaliados após a submissão das diferentes amostras à diferentes temperaturas. No estágio de pupa, as amostras foram tratadas nas temperaturas de 17, 20, 25 e 30oC. As estruturas analisadas, em machos e fêmeas foram as cerdas frontais (FO), orbitais (OB), pós-oculares (PO), o comprimento e largura das asas. Nos machos, além dessas estruturas, foi incluída a análise do comprimento de uma das cerdas orbitais, a supra-fronto-orbital (SFO), que apresenta dimorfismo sexual. A variação numérica das cerdas FO e OB foi muito baixa em todas as amostras, não permitindo uma análise da assimetria. A assimetria das demais características, tanto merísticas como métricas, mostrou ser compatível com o modelo da assimetria flutuante (AF). O grau de assimetria de cada estrutura não diferiu entre machos e fêmeas, mas foi significativamente mais alto na amostra da população de laboratório do que na amostra da população natural. No entanto, a assimetria holística (somatória da AF das diferentes estruturas) não mostrou diferenças entre as duas amostras. Nas amostras submetidas a diferentes temperaturas foram observadas alterações significativas no grau de assimetria das estruturas, mas nenhuma alteração no tipo de assimetria que continuou sendo caracterizada como flutuante. Essas análises mostraram não haver diferenças entre os sexos, nem interações entre sexo e temperatura, mas apenas diferenças significativas entre as temperaturas. A assimetria flutuante das cerdas pós-oculares aumenta com o elevação da temperatura, a AF do comprimento das asas e da cerda SFO (nos machos) não mostra correlação com as temperaturas e os resultados indicam que a AF da largura das asas é mais elevada nas temperaturas extremas que nas intermediárias. A comparação da assimetria holística entre as amostras das diferentes temperaturas mostrou que as diferenças não foram significativas. Os resultados indicam que a assimetria das 52 cerdas pós-oculares e das medidas do largura das asas apresentam potencial para evidenciar eventuais estresses durante o desenvolvimento desses insetos. Indicam, também, que a utilização de uma assimetria holísitca pode mascarar possíveis diferenças da assimetria flutuante de estruturas individuais. / Asymmetry of five traits of the fruit fly Ceratitis capitata, an introduced insect pest in Brazil, was analysed in order to evaluate if they present potencial to be used as bioindicators of the \"quality\" of these insects. Samples from a natural population and from a laboratory colony were studied. Moreover, asymmetry was measured in samples from the laboratory colony maintained during the pupal stage, in the temperatures of 17, 20, 25 and 30oC. The analysed traits of males and females, were the frontal, the orbital and the postocular bristles, measurement of the length and cross diameter of the wings and the length of the supra-frontoorbital bristles in the males that show a pronounced sexual dimorphism. Since the numerical variation of the frontal and orbital bristles was very low in all samples it was not possible to analyse the variation in terms of asymmetry. For all other traits, meristic or metric, asymmetry was characterized as following the fluctuating asymmetry (AF) model. AF of the different traits does not differ between sexes, but was significantly higher in the laboratory sample than in the sample from the natural population. No significant differences, however, were found in the holistic asymmetry (sum of AF of different traits) between the two samples. In relation to the experiments conducted in different temperatures, no variations in AF levels were observed between sexes, nor interactions between sex and temperatures. However, significant differences were observed among the samples submitted to different temperatures. AF of the postocular bristles increases proportionaly to the increment of the temperature, while AF of wings and supra-fronto-orbital bristles (in males) lengths showed no correlations with the temperatures, and AF of the cross diameter of wings seems to be higher at the extreme temperatures than at the intermediate ones. When a holistic AF was applied, no significant differences among the temperature samples were observed. The results indicate that asymmetry of the postocular bristles and the length of the wings are parameters showing potencial use as indicators of stresses during development of these insects. They also indicate that a holistic asymmetry may mask variations in the asymmetry of individual traits.

Submitted by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-05T14:11:26Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) MARCIA ROSULA POETINI SILVA.pdf: 1891478 bytes, checksum: e4874e22f3dbc89ee3033d4701e4a8a2 (MD5) / Approved for entry into archive by Marcos Anselmo (marcos.anselmo@unipampa.edu.br) on 2017-06-05T14:11:58Z (GMT) No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) MARCIA ROSULA POETINI SILVA.pdf: 1891478 bytes, checksum: e4874e22f3dbc89ee3033d4701e4a8a2 (MD5) / Made available in DSpace on 2017-06-05T14:11:58Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) MARCIA ROSULA POETINI SILVA.pdf: 1891478 bytes, checksum: e4874e22f3dbc89ee3033d4701e4a8a2 (MD5) Previous issue date: 2017-02-21 / Os flavonoides são compostos naturais presentes em diversos tipos de plantas, são quimicamente classificados como polifenóis e geralmente encontrados em sua forma livre ou glicosilada. A Hesperidina (Hsd) é um flavonoide cítrico, encontrado principalmente em frutas cítricas como a laranja e o limão, classificado como flavanona glicosídica e possui propriedades antioxidantes, anti-inflamatórias, anticancerígenas, antivirais, hipolipidêmica, entre outras. O ferro (Fe) é um nutriente fundamental para todas as células vivas, mas em excesso pode ser tóxico, por causar danos oxidativos através da formação de radicais livres, como a reação de fenton, os quais resultam em fenômenos de estresse oxidativo. Uma desregulação no metabolismo do Fe está associado com dano celular e também a doenças neurodegenerativas como a doença de Parkinson e Alzheimer. O objetivo deste estudo foi avaliar o efeito neuroprotetor da hesperidina na exposição aguda ao ferro na forma de sulfato ferroso em Drosophila melanogaster adultas macho. As moscas foram divididas em quatro grupos: 1) controle, 2) hesperidina (10 μM), 3) Fe (20 mM) na forma de sulfato ferroso, 4) hesperidina (10 μM) + Fe (20 mM). As moscas foram concomitantemente expostas ao Fe e Hsd na dieta em papel filtro (dissolvidos em sacarose 1 %) por 48 horas, de acordo com seus respectivos grupos. Para as análises in vivo foram avalizadas a sobrevivência e os comportamentos (testes como geotaxia negativa, campo aberto e base/topo) e ex vivo a atividade da acetilcolinesterase (AChE) na cabeça e no corpo, viabilidade celular e mitocondrial e determinação dos níveis de dopamina na cabeça das moscas. A atividade da catalase (CAT), superóxido dismutase (SOD) e glutationa S-transferase (GST), os níveis de peroxidação lipídica (TBARS), níveis de espécies reativas (ER), o teor de tióis não protéicos (NPSH), os tióis totais e os níveis de ferro na cabeça e no corpo de Drosophila melanogaster também foram avaliados. A exposição ao Fe aumentou significativamente a mortalidade das moscas, enquanto que as sobreviventes apresentaram déficit locomotor significativo com atividade aumentada de AChE. No entanto, a suplementação dietética com Hsd causou uma diminuição significativa na mortalidade, melhora da atividade locomotora e restauração da atividade da AChE em moscas expostas ao Fe. O metal também causou decréscimo nos níveis de tióis totais e não proteicos e na atividade das enzimas SOD, CAT e GST, acompanhadas com aumento significativo na geração de ER e TBARS, assim como aumento nos níveis de Fe na cabeça e no corpo e redução nos níveis de dopamina na cabeça das moscas expostas ao elemento. Efeitos esses prevenidos pela hesperidina. A hesperidina apresentou o potencial antioxidante e amenizou o efeito causado pela exposição aguda ao Fe em Drosophila melanogaster. / Flavonoids are natural compounds present in many plant types, are chemically classified as polyphenols and are generally found in their free or glycosylated form. Hesperidin (Hsd) is a citrus flavonoid, found mainly in citrus fruits such as orange and lemon, classified as flavanone glycosidic and has antioxidant, anti-inflammatory, anticancer, antiviral, hypolipidemic properties, among others. Iron (Fe) is a fundamental nutrient for all living cells, but in excess it can be toxic because it causes oxidative damage through the formation of free radicals, such as fenton reaction, which result in phenomena of oxidative stress. Deregulation in the metabolism of Fe is associated with cellular damage and also neurodegenerative diseases such as Parkinson's disease and Alzheimer's. The objective of this study was to evaluate the neuroprotective effect of hesperidin on acute exposure to iron in the form of ferrous sulfate in adult male Drosophila melanogaster. The flies were divided into four groups: 1) control, 2) hesperidin (10 μM), 3) Fe (20 mM) as ferrous sulfate, 4) hesperidin (10 μM) + Fe (20 mM). Flies were concomitantly exposed to Fe and Hsd in the diet on filter paper (dissolved in 1% sucrose) for 48 hours, according to their respective groups. Survival and behaviors (tests such as negative geotag, open field and base / top) and ex vivo acetylcholinesterase (AChE) activity in head and body, cell and mitochondrial viability and determination of dopamine on the head of flies. The activity of catalase (CAT), superoxide dismutase (SOD) and glutathione Stransferase (GST), levels of lipid peroxidation (TBARS), reactive species levels (RS), nonprotein thiol content (NPSH), total thiols and iron levels in the head and body of Drosophila melanogaster were also evaluated. Exposure to Fe significantly increased fly mortality, while survivors had significant locomotor deficits with increased AChE activity. However, dietary supplementation with Hsd caused a significant decrease in mortality, improvement of locomotor activity and restoration of AChE activity in Fe-exposed flies. The metal also caused a decrease in the levels of total and non-protein thiols and in the activity of SOD enzymes , CAT and GST, accompanied with a significant increase in RS and TBARS generation, as well as increase in Fe levels in the head and body and reduction in dopamine levels in the head of the flies exposed to the element. These effects prevented by hesperidin. Hesperidin presented the antioxidant potential and attenuated the effect caused by the acute exposure to Fe in Drosophila melanogaster.

A técnica do inseto estéril visa a indução de esterilidade em fêmeas selvagens por meio do acasalamento com machos estéreis liberados em grandes quantidades no ambiente. Os insetos liberados devem ser capazes de competir com os selvagens pela cópula com as fêmeas, fertilizar seus ovos e evitar que ela copule novamente. A recópula com machos selvagens pode interferir na eficiência da técnica por resultar em ovos férteis. Não é conhecido como a sequência de cópula-recópula com machos estéreis e/ou selvagens determina a fertilidade dos ovos na mosca-da-fruta, Ceratitis capitata (Wied., 1824) (Diptera: Tephritidae), nem as conseqüências deste comportamento, o que justificou o presente trabalho. Os experimentos foram realizados em laboratório, na Embrapa Semi-Árido, Petrolina-PE, sob condições ambientes de temperatura e umidade relativa, para determinar a influência do tipo e ordem das cópulas na indução de esterilidade, além de parâmetros do comportamento de recópula, como frequência recópula entre as fêmeas, número de cópulas for fêmea, tempo de cópula e recópula, período refratário e competitividade sexual dos machos. Foi também avaliada a interferência do tratamento aromático dos machos estéreis com óleo de gengibre sobre a recópula das fêmeas. A Biofábrica Moscamed Brasil, Juazeiro- BA forneceu os insetos estéreis, e os selvagens foram provenientes de pupas coletadas de frutos infestados em áreas frutícolas na região do Submédio do Vale do São Francisco. Na presença de machos estéreis e selvagens concorrendo pelas cópulas na proporção de 5 estéreis: 1 selvagem, 63% das fêmeas recopularam em média 3,37 vezes com curto período refratário entre a cópula e a primeira recópula. O tratamento dos machos com óleo de gengibre diminuiu significativamente a taxa de recópula. A aromaterapia dos machos não reduziu a fecundidade e nem conferiu aos machos vantagem da competição espermática, entretanto aumentou a indução de esterilidade em fêmeas selvagens que recopularam. O segundo macho a copular a fêmea apresentou maior vantagem reprodutiva em curto período refratário. Conclui-se que para que a técnica do inseto estéril seja eficiente, é necessário que haja sempre machos estéreis de boa qualidade no campo para recopularem as fêmeas em curto período refratário. / The sterile insect technique (SIT) aim at the induction of sterility in wild females by mating with sterile males released in great amounts in the field. These released males must compete with wild ones being able to attract and mate wild females, fertilize their eggs and avoid remating with a wild male that would lead to fertile eggs and consequently reduce the efficiency of the technique. The circumstances in which remating of Ceratitis capitata (Wied., 1824) (Diptera: Tephritidae) females interfere with the SIT, as well as the consequences of this behavior are not well known, what justified the present study. The experiments were carried out at the Embrapa Semi-Árido, Petrolina-PE, inside the laboratory under ambient conditions of temperature and relative humidity to determine the influence of the order of mating type in the induction of sterility. The parameters evaluated to better understand the remating behavior were remating frequency, number of matings per female, mating and remating time, refractory period, sexual competitiveness of males, and the interference of males aromatherapy with ginger root oil in the females remating. Moscamed facility, Juazeiro-BA, provided the sterile males and the wild ones were from pupae collected from infested fruits from commercial orchards in the São Francisco River Valley. In the presence of sterile and wild males in competition (5 sterile: 1wild), 63% of females remated in average 3.37 times in short refractory period between the mating and the first remating. The males aromatherapy with ginger root oil reduced significantly the remating rate, but did not reduce the fecundity, neither confer advantage to the males in the sperm competition, however increased the induction of sterility in wild females multiply mated. The second male to mate the female presented reproductive advantage if the refractory period was short. For the SIT be efficient the sterile males in the field must always have great quality to remate the females in a short refractory period and thus induce sterility in the wild population.