Dissertations / Theses on the topic 'Fruit fly pests'

Doctor of Philosophy(PhD),<br>Until recently, Northwestern Australia was thought to be relatively free of serious fruit fly pests. Although a noxious strain, present in Darwin since 1985, was widely believed to be an infestation of the Queensland fruit fly, Bactrocera tryoni, from the East coast, the fruit flies present outside this area were believed to be the benign endemic species, B. aquilonis. However, during the year 2000, infestations of fruit flies were discovered on major commercial crops in both Western Australia and the Northern Territory. It was not known whether these outbreaks were due to an invasion of the major pest species, Bactrocera tryoni, a change in the behaviour of B. aquilonis, or a hybridisation event between the two species. Finding the source of these outbreaks has been complicated by the fact that, since B. tryoni and B. aquilonis are virtually indistinguishable morphologically, it was not known which species are present in the region. Traditionally any tryoni complex fly caught in the Northwest was called B. aquilonis based solely on location. In order to get a good population profile of the region, an extensive trapping program was set up to include flies from urban areas, commercial crops and natural areas where the benign strain is thought to remain. Tests of genetic differentiation and clustering analyses revealed a high degree of homogeneity in the Northwest samples, suggesting that just one species is present in the region. The Northwest samples were genetically differentiated from the Queensland samples but only to a small degree (FST =0.0153). MtDNA sequencing results also showed a small degree of differentiation between these regions. A morphological study of wing shape indicated that there are some minor identifiable morphological differences between East coast and Northwest laboratory reared flies. This difference was greater than that seen between B. jarvisi populations across the same geographic range. The results suggest that the flies caught in the Northwest are a separate population of B. tryoni. Soon after pest flies were discovered in Darwin, a population became established in Alice Springs. This population had a low genetic diversity compared with Queensland and Darwin populations, and showed evidence of being heavily founded. In 2000, an outbreak was discovered in the nearby town of Ti Tree. Due to the geographic and genetic similarity of these populations, Alice Springs was determined to be the source of the Ti Tree outbreak. To investigate the founding of these populations, a program was developed to estimate the propagule size. Using a simulation method seven different statistics were tested for estimating the propagule size of an outbreak population. For outbreaks originating from populations with high genetic diversity, the number of alleles was a good estimator of propagule size. When, however, the genetic diversity of the source population was already reduced, allele frequency measures, particularly the likelihood of obtaining the outbreak population from the source population, gave more accurate estimates. Applying this information to the Alice Springs samples, it was estimated that just five flies were needed to found the major population in and around Alice Springs. For Ti Tree, the propagule size was estimated to be 27 flies (minimum 10). In 2000, a much larger outbreak occurred in the developing horticultural region of Kununurra in northern Western Australia. An important question for the management of the problem is whether there is an established fly population or the flies are reinvading each year. This population was found to have a large amount of gene flow from the Northern Territory. Within the Kununurra samples, one group of flies was genetically differentiated from all the other samples. This group came from a small geographic area on the periphery of Kununurra and appeared to be the result of an invasion into this area at the time when the population was building up following the dry season. A further threat to the Northwest horticultural regions comes from B. jarvisi. A recent increase in the host range of this species has lead to speculation that it may become a greater pest in Northwestern Australia. At the present time, protocols for the population monitoring and disinfestation of this species are not in place. Here it is shown that B. jarvisi eggs are more heat tolerant than B. tryoni eggs and that monitoring of B. jarvisi populations is possible using cue lure traps placed according to fruiting time and location of their favoured host, Planchonia careya.

Until recently, Northwestern Australia was thought to be relatively free of serious fruit fly pests. Although a noxious strain, present in Darwin since 1985, was widely believed to be an infestation of the Queensland fruit fly, Bactrocera tryoni, from the East coast, the fruit flies present outside this area were believed to be the benign endemic species, B. aquilonis. However, during the year 2000, infestations of fruit flies were discovered on major commercial crops in both Western Australia and the Northern Territory. It was not known whether these outbreaks were due to an invasion of the major pest species, Bactrocera tryoni, a change in the behaviour of B. aquilonis, or a hybridisation event between the two species. Finding the source of these outbreaks has been complicated by the fact that, since B. tryoni and B. aquilonis are virtually indistinguishable morphologically, it was not known which species are present in the region. Traditionally any tryoni complex fly caught in the Northwest was called B. aquilonis based solely on location. In order to get a good population profile of the region, an extensive trapping program was set up to include flies from urban areas, commercial crops and natural areas where the benign strain is thought to remain. Tests of genetic differentiation and clustering analyses revealed a high degree of homogeneity in the Northwest samples, suggesting that just one species is present in the region. The Northwest samples were genetically differentiated from the Queensland samples but only to a small degree (FST =0.0153). MtDNA sequencing results also showed a small degree of differentiation between these regions. A morphological study of wing shape indicated that there are some minor identifiable morphological differences between East coast and Northwest laboratory reared flies. This difference was greater than that seen between B. jarvisi populations across the same geographic range. The results suggest that the flies caught in the Northwest are a separate population of B. tryoni. Soon after pest flies were discovered in Darwin, a population became established in Alice Springs. This population had a low genetic diversity compared with Queensland and Darwin populations, and showed evidence of being heavily founded. In 2000, an outbreak was discovered in the nearby town of Ti Tree. Due to the geographic and genetic similarity of these populations, Alice Springs was determined to be the source of the Ti Tree outbreak. To investigate the founding of these populations, a program was developed to estimate the propagule size. Using a simulation method seven different statistics were tested for estimating the propagule size of an outbreak population. For outbreaks originating from populations with high genetic diversity, the number of alleles was a good estimator of propagule size. When, however, the genetic diversity of the source population was already reduced, allele frequency measures, particularly the likelihood of obtaining the outbreak population from the source population, gave more accurate estimates. Applying this information to the Alice Springs samples, it was estimated that just five flies were needed to found the major population in and around Alice Springs. For Ti Tree, the propagule size was estimated to be 27 flies (minimum 10). In 2000, a much larger outbreak occurred in the developing horticultural region of Kununurra in northern Western Australia. An important question for the management of the problem is whether there is an established fly population or the flies are reinvading each year. This population was found to have a large amount of gene flow from the Northern Territory. Within the Kununurra samples, one group of flies was genetically differentiated from all the other samples. This group came from a small geographic area on the periphery of Kununurra and appeared to be the result of an invasion into this area at the time when the population was building up following the dry season. A further threat to the Northwest horticultural regions comes from B. jarvisi. A recent increase in the host range of this species has lead to speculation that it may become a greater pest in Northwestern Australia. At the present time, protocols for the population monitoring and disinfestation of this species are not in place. Here it is shown that B. jarvisi eggs are more heat tolerant than B. tryoni eggs and that monitoring of B. jarvisi populations is possible using cue lure traps placed according to fruiting time and location of their favoured host, Planchonia careya.

Outbreaks of insect pests pose a serious threat to local economies and global food production, with as much as 15% of global crop production lost to herbivorous insects annually. Outbreaks of transboundary pests and diseases that affect food crops have increased in frequency in conjunction with globalization, international trade and the impacts of climate change. Indeed, increasing global temperatures are predicted to increase the distribution, rate of development, survival and population density of many pest insects. Such changes have important ramifications for host plant exploitation. The Queensland fruit fly (Bactrocera tryoni) is Australia’s worst horticultural pest, and is feared by international buyers of Australian produce. Like other Tephritid fruit fly species, B. tryoni has the potential to breach quarantine barriers via human mediated transport, and can rapidly establish in ‘new’ environments. This pest species is responsible for an estimated AU$28.5 million in annual yield loss, management costs and loss to domestic and international markets. Increasing and ongoing outbreaks of B. tryoni in Australia’s major growing regions has put international trade in jeopardy.<br>Thesis (PhD Doctorate)<br>Doctor of Philosophy (PhD)<br>Griffith School of Environment<br>Science, Environment, Engineering and Technology<br>Full Text

The biology of key citrus pests Thaumatotibia leucotreta Meyrick (Lepidoptera: Tortricidae), Ceratitis capitata Wiedemann (Diptera: Tephritidae) and Ceratitis rosa Karsch (Diptera: Tephritidae) includes their dropping from host plants to pupate in the soil below citrus trees. Since most EP fungi are soil-borne microorganisms, the development and formulation of alternative control strategies using these fungi as subterranean control agents, targeted at larvae and pupae in the soil, can potentially benefit existing IPM management of citrus in South Africa. Thus, a survey of occurrence of entomopathogenic fungi was undertaken on soils from citrus orchards and natural vegetation (refugia) on conventionally and organically managed farms in the Eastern Cape Province in South Africa. A method for baiting soil samples with citrus pest T. leucotreta and C. capitata larvae, as well as with the standard bait insect, Galleria mellonella Linnaeus (Lepidoptera: Pyralidae), was implemented. Sixty-two potentially useful entomopathogenic fungal isolates belonging to four genera were collected from 288 soil samples, an occurrence frequency of 21.53%. The most frequently isolated entomopathogenic fungal species was Beauveria bassiana (Balsamo) Vuillemin (15.63%), followed by Metarhizium anisopliae var. anisopliae (Metschnikoff) Sorokin (3.82%). Galleria mellonella was the most effective insect used to isolate fungal species (χ2=40.13, df=2, P≤ 0.005), with a total of 45 isolates obtained, followed by C. capitata with 11 isolates, and T. leucotreta with six isolates recovered. There was a significantly (χ2=11.65, df=1, P≤ 0.005) higher occurrence of entomopathogenic fungi in soil samples taken from refugia compared to cultivated orchards of both organically and conventionally managed farms. No significant differences were observed in the recovery of fungal isolates when soil samples from both farming systems were compared. The physiological effects and host range of 21 indigenous fungal isolates obtained in the Eastern Cape were investigated in the laboratory to establish whether these isolates could be effectively used as biological control agents against the subterranean life stages of C. rosa, C. capitata and T. leucotreta. When these pests were treated with a fungal concentration of 1 x 10⁷ conidia ml⁻¹, the percentage of T. leucotreta adults which emerged in fungal treated sand ranged from 5 to 60% (F=33.295; df=21; P=0.0001) depending on fungal isolate and the percentage of pupae with visible signs of mycosis ranged from 21 to 93% (F= 96.436; df=21; P=0.0001). Based on fungal isolates, the percentage adult survival in C. rosa and C. capitata ranged from 30 to 90% and 55 to 86% respectively. The percentage of C. rosa and C. capitata puparia with visible signs of mycosis ranged from 1 to 14% and 1 to 11% respectively. Deferred mortality due to mycosis in C. rosa and C. capitata adult flies ranged from 1 to 58% and 1 to 33% respectively, depending on fungal isolate. Entomopathogenic fungal isolates had a significantly greater effect on the adults of C. rosa and C. capitata than they did on the puparia of these two fruit fly species. Further, C. rosa and C. capitata did not differ significantly in their response to entomopathogenic fungi when adult survival or adult and pupal mycosis were considered. The relative potency of the four most virulent Beauveria isolates as well as the commercially available Beauveria bassiana product, Bb Plus® (Biological Control Products, South Africa), were compared against one another as log-probit regressions of mortality against C. rosa, C. capitata and T. leucotreta which all exhibited a dose-dependent response. Against fruit flies the estimated LC50 values of all five Beauveria isolates ranged from 5.5 x 10¹¹ to 2.8 x 10¹² conidia/ml⁻¹. There were no significant differences between the relative potencies of these five fungal isolates. When T. leucotreta was considered, isolates: G Moss R10 and G 14 2 B5 and Bb Plus® were significantly more pathogenic than G B Ar 23 B3 and FCM 10 13 L1. The estimated LC₅₀ values of the three most pathogenic isolates ranged from 6.8 x 10⁵ to 2.1 x 10⁶ conidia/ml⁻¹, while those of the least pathogenic ranged from 1.6 x 10⁷ to 3.7 x 10⁷ conidia/ml⁻¹. Thaumatotibia leucotreta final instar larvae were exposed to two conidial concentrations, at four different exposure times (12, 48, 72 and 96 hrs) and showed an exposure time-dependant relationship (F=5.43; df=3; P=0.001). At 1 x 10⁷conidia/ml⁻¹ two Beauveria isolates: G Moss R10 and G 14 2 B5 were able to elicit a response in 50% of test insects at 72 hrs (3 days) exposure. Although a limited amount of mycosis was observed in the puparia of both fruit fly species, deferred adult mortality due to mycosis was high. The increased incidence of adult mortality suggests that post emergence mycosis in adult fruit flies may play a more significant role in field suppression than the control of fruit flies at the pupal stage. The increased incidence of pupal mortality, as well as the relatively low concentrations of conidia required to elicit meaningful responses in T. leucotreta pupae may suggest that pre-emergent control of false codling moth will play a more significant role in field suppression than the control of adult life stages using indigenous isolates of entomopathogenic fungi. Various entomopathogenic fungal application techniques targeted at key insect pests within integrated pest management (IPM) systems of citrus are discussed.

Thesis (MSc)--Stellenbosch University, 2011.<br>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.<br>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.

Thesis (MScAgric)--University of Stellenbosch, 2002.<br>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.<br>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.

Thesis (MSc)--University of Stellenbosch, 2003.<br>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.<br>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.

Made available in DSpace on 2015-09-25T12:18:48Z (GMT). No. of bitstreams: 1 FLAVIA QUEIROZ DE OLIVEIRA.pdf: 771334 bytes, checksum: 4a8901cbaaff36710ad317e89ac63ae6 (MD5) Previous issue date: 2011-01-31<br>Coordenação de Aperfeiçoamento de Pessoal de Nível Superior<br>The red mombin fruit Spondias purpurea is a tropical fruit of vital importance to farmers in semi-arid region of Brazil, but it presents as a major factor limiting the occurrence of fruit flies Ceratitis capitata (Diptera: Tephritidae). Several papers have discussed the applicability of natural products such as essential oils, this pest control programs. However little is known about the effectiveness of this tactic in controlling C. capitata, as well as the impact of alternative technology in fruit quality. In this study we evaluated the effects of alternative substances as potential repellents and insecticides to C. capitata, and fruit quality of red mombin fruit. The experiments were performed at the Laboratory of Entomology UFPB Areia/PB. Three experiments were conducted: repellent activity (test I), insecticidal activity (test II) and physical and chemical quality of fruits (test III). For the all tests were used for red mombin fruit ripe fruit, water and disinfected with hypochlorite 0.1%, and dry in paper towels at room temperature. They were then treated with the following products: proagrim, essential oil of fennel and orange essential oil, both of the following concentrations, 0.0 (control), 1.0, 1.5, 2.0, 2.5 and 3.0% (w/v). For treatment of fruit products were diluted in water. While the second experiment, we used the same products and concentration of which was that the insecticidal activity via topical application of products on eggs, larvae of 1st, 2nd and 3rd instars and pupae. The results obtained in the first trial, no choice, revealed that the tested products significantly affected the fruit of red mombin fruit infestation by C. capitata. The effect of pesticides on fruit infestation reduction was dose-dependent. The average fertility of C. capitata (number of larvae per fruit) in fruit of red mombin fruit ranged from 1.65 (1%) to 1.025 (3%) when applied orange oil, 0.25 (1%) 0,075 (3%) for fennel oil and 2.1 (1%) to 0.95 (3%) when applied proagrim. The free-choice test results confirmed that no-choice, demonstrating the repellent action of the tested products. The preference index recorded was 0.5398 for orange oil; 0.3435 to 0.1717 and proagrim product for oil and fennel. In the trial of insecticide activity, it was found that, regardless of the product and the developmental stage of C. capitata mortality was directly related to increased concentrations. The median lethal concentrations (LC) of the product proagrim estimated for eggs of C. capitata was 1.6965% (w/v), which was 50higher than the average concentrations lethal (LC) estimated for larvae of 1st, 2nd and 3rd instar larvae of C. capitata, corresponding to 0.3409, 0.2277 and 0.1800% (w/v), respectively. While the estimated LC5050 of fennel oil to larvae of 1st, 2nd and 3rd instar were 0.5419, 0.5189, and 0.5464% (w/v), respectively. Low-dose response was found in all stages evaluated C. capitata after application of orange oil product. Regarding the effects of these products on fruit quality of red mombin fruit, it was found that no there is product-independent linear relationship between ° Brix and pH vs concentration vs concentration of fruit red mombin fruit. Products proagrim orange oil and promote greater weight losses of fruit pulp of red mombin fruit, from product oil of fennel. However, concentrations above 2.5% of fennel oil in fruits of red mombin fruit should be taken judiciously, in order to avoid compromising the physical quality, as well as reducing the degree Brix of fruit pulp of red mombin fruit.<br>A ciriguela Spondias purpurea é uma frutífera tropical de importância vital para os agricultores do semi-árido do Brasil, porém tem como um dos fatores limitantes a ocorrência de moscas-das-frutas Ceratitis capitata (Diptera: Tephritidae). Diversos trabalhos têm discutido a aplicabilidade de produtos naturais, como óleos essenciais, em programas de controle desta praga. No entanto, pouco se sabe sobre a eficiência dessa tática no controle de C. capitata, assim como o impacto dessa tecnologia alternativa na qualidade dos frutos. Nesse trabalho avaliou-se os efeitos de substâncias alternativas como potenciais produtos repelentes e inseticidas à C. capitata, e na qualidade de frutos de ciriguela. Os experimentos foram realizados no Laboratório de Entomologia da UFPB Areia. Foram executados três ensaios: I- Ensaio de atividade repelente, II- Ensaio de atividade inseticida e III- Ensaio de qualidade físico-química dos frutos. Para todos os ensaios foram utilizados frutos de ciriguela maduros, higienizados com água e hipoclorito a 0,1%, e secos sob papel absorvente em temperatura ambiente. Em seguida foram tratados com os seguintes produtos: proagrim, óleo essencial de erva-doce e óleo essencial de laranja, ambos nas seguintes concentrações, 0,0 (testemunha); 1,0; 1,5; 2,0; 2,5 e 3,0% (m/v). Para o tratamento dos frutos os produtos foram diluídos em água. Enquanto que no segundo ensaio, foram utilizados os mesmos produtos e concentrações, sendo que foi avaliada a atividade inseticida através de aplicações tópicas dos produtos em ovos, larvas de 1º, 2º e 3º instar e pupas. Os resultados obtidos no primeiro ensaio, sem chance de escolha, revelaram que os produtos testados afetaram significativamente a infestação de frutos de ciriguela por C. capitata. O efeito dos produtos na redução da infestação de frutos foi tipo dose-dependente. A fecundidade média de C. capitata (número de larvas/fruto) em frutos de ciriguela variou entre 1,65 (1%) a 1,025 (3%) quando aplicado óleo de laranja; 0,25 (1%) a 0,075 (3%) para óleo de erva-doce e de 2,1 (1%) a 0,95 (3%) quando aplicado o proagrim. O ensaio com chance de escolha confirmou os resultados daquele sem chance de escolha, demonstrando a ação repelente dos produtos testados. O índice de preferência registrado foi de 0,5398, para óleo de laranja; 0,3435 para o produto proagrim e de 0,1717 para óleo de erva-doce. No ensaio de atividade inseticida, verificou-se que, independente do produto e do estágio de desenvolvimento de C. capitata a mortalidade foi diretamente relacionada com o aumento das concentrações. A concentração média letal (CL) do produto proagrim estimada para ovos de C. capitata foi de 1,6965 % (m/v), a qual foi superior as concentrações médias letais (CL) estimadas para larvas de 1º, 2º e 3º ínstar de C. capitata, correspondendo a 0,3409, 0,2277 e 0,1800 % (m/v), respectivamente. Enquanto que as CL 50 50 estimadas do óleo de erva-doce para larvas de 1º, 2º e de 3º instar foram de 0,5419, 0,5189, e de 0,5464 % (m/v), respectivamente. Baixa dose-resposta foi encontrada em todos os estágios avaliados de C. capitata após aplicação do produto óleo de laranja. Com relação aos efeitos destes produtos na qualidade de frutos de ciriguela, constatou-se que independente do produto não existe relação linear entre °Brix vs concentração e pH vs concentração de frutos de ciriguela. Os produtos proagrim e óleo de laranja promovem maiores perdas de peso de polpa de fruto de ciriguela, em relação ao produto óleo de erva-doce. No entanto, concentrações acima de 2,5% do óleo de erva-doce em frutos de ciriguela devem ser adotadas de forma criteriosa, para que se evite o comprometimento da qualidade física, assim como a redução do grau Brix de polpas de frutos de ciriguela.

Invasive species are recognised as one of the most important, growing threat to food biosecurity, causing a significant economic loss in agricultural systems. Despite their damaging effect, they are attractive models for the study of evolution and adaptation in newly colonised environments. Currently, the global climate represents one key potential stressors to impact the food biosecurity because of its influence in the distribution and change in the abundance of agricultural pests. The tephritid fruit flies (Diptera: Tephritidae) contain some of the most successful invaders and most devastating agricultural pests recognised worldwide. Among them, the Mediterranean fruit fly Ceratitis capitata and the South American fruit flies in the genus Anastrepha are particularly important for crop production. Insecticides have been used extensively for their control. This thesis investigates factors that are related to invasiveness in these species, in order to provide novel information that will ultimately improve management control methods. First, environmental niche modelling was used to determine the influence of climate change in the potential habitat distribution of C. capitata, predicting both polewards expansion as well as greater connectivity. Next, historical global dispersal patterns of the medfly over the past two centuries were investigated using molecular and genetic approaches. In Chapter 4, different attempts to identify the point mutation G328A Ccace2 gene that confers resistance to insecticides were assessed at local and intercontinental scale, in part by studying museum specimens from before and after the use of pesticides. Additionally, to improve genetic knowledge of this invasive species, the mitogenome of different species of Anastrepha were sequenced and analysed together with others tephritid. This investigation provides crucial information revealing the evolutionary factors that influence the medfly’s successful invasions and will contribute to the development of evidence-driven pest management protocols, especially in the Americas, including the choice among different control methods as well as the establishment of quarantine procedures to interrupt colonisation routes.

Bactrocera tryoni, the Queensland fruit fly, is established along the entire Australian east coast. It is a major pest of horticulture and arguably the worst horticultural insect pest in Australia. Adult flies lay eggs into fruit and resultant larvae feed on the flesh of the fruit. The population biology of B. tryoni has been well studied in temperate regions, where it has been established that climatic factors, particularly temperature and rainfall, limit population growth. In contrast, in subtropical and tropical regions, the population dynamics of the fly have been little studied. This thesis investigates the fly's phenology and abundance changes across subtropical and tropical Queensland and asks what factors govern the population cycles of B. tryoni in this state. Winter breeding and abundance of the fly, a component of the seasonal cycle which in south-east Queensland is fundamentally different from that observed in temperate Australia, is also investigated. A historical, extensive multi-year and multi-site trapping data set with from across Queensland was analysed to look at the effects of temperature, rainfall and relative humidity on B. tryoni trap catch. Trap data was further compared with the predicted phenology data generated by a DYMEX® based B. tryoni population phenology model. The phenology model used was based on a previously published model, but was also modified to more explicitly look at the effects of host plant availability and the presence or absence of non-reproductive over-wintering flies. Over-wintering field cage studies and a winter-spring field trapping study, both carried out in Brisbane, supplied additional data on B. tryoni's population abundance and capacity to breed during winter in the subtropics. Results show significant variation of monthly fly abundance for nine sites across Queensland. Abundance changed across sites in non-predictable ways. Annual population phenology within a site was, for some sites, highly consistent from year to year, but inconsistent for other sites. All sites in the subtropics showed some form of population depression during the cooler months, but breeding was continuous, albeit reduced at nearly all sites. Some tropical sites, where the climate is regarded as highly favourable for B. tryoni, still showed dramatic peaks and troughs in annual population abundance. There were relatively few significant correlations observed between weather factors and fly populations for any site. Output from the DYMEX population model suggested that fruit availability is a major driver of population dynamics in the tropical north of the state, while weather is more important in the subtropical south. The population dynamics of B. tryoni at sites along the central Queensland coast, where it is assumed that a mix of both weather and host fruit availability drive local populations, were poorly captured by the population model. Field cage results showed that B. tryoni successfully bred during winter in Brisbane, with pupal emergence starting in mid-winter (1st week of August), peaking in early spring (2nd week of September). Trap catch at orchards in Brisbane increased with increasing temperature and fruit availability, but diminished with decreasing temperature and fruit availability. The results suggest that B. tryoni has an optimal climate for population growth in the tropics, but fruit availability for offspring production limits population growth. In the subtropics however, both climate and fruit availability determine the population size. Winter temperatures are marginal for B. tryoni population growth in the subtropics.

Bactrocera tryoni, the Queensland fruit fly, is established along the entire Australian east coast. It is a major pest of horticulture and arguably the worst horticultural insect pest in Australia. Adult flies lay eggs into fruit and resultant larvae feed on the flesh of the fruit. The population biology of B. tryoni has been well studied in temperate regions, where it has been established that climatic factors, particularly temperature and rainfall, limit population growth. In contrast, in subtropical and tropical regions, the population dynamics of the fly have been little studied. This thesis investigates the fly's phenology and abundance changes across subtropical and tropical Queensland and asks what factors govern the population cycles of B. tryoni in this state. Winter breeding and abundance of the fly, a component of the seasonal cycle which in south-east Queensland is fundamentally different from that observed in temperate Australia, is also investigated. A historical, extensive multi-year and multi-site trapping data set with from across Queensland was analysed to look at the effects of temperature, rainfall and relative humidity on B. tryoni trap catch. Trap data was further compared with the predicted phenology data generated by a DYMEX® based B. tryoni population phenology model. The phenology model used was based on a previously published model, but was also modified to more explicitly look at the effects of host plant availability and the presence or absence of non-reproductive over-wintering flies. Over-wintering field cage studies and a winter-spring field trapping study, both carried out in Brisbane, supplied additional data on B. tryoni's population abundance and capacity to breed during winter in the subtropics. Results show significant variation of monthly fly abundance for nine sites across Queensland. Abundance changed across sites in non-predictable ways. Annual population phenology within a site was, for some sites, highly consistent from year to year, but inconsistent for other sites. All sites in the subtropics showed some form of population depression during the cooler months, but breeding was continuous, albeit reduced at nearly all sites. Some tropical sites, where the climate is regarded as highly favourable for B. tryoni, still showed dramatic peaks and troughs in annual population abundance. There were relatively few significant correlations observed between weather factors and fly populations for any site. Output from the DYMEX population model suggested that fruit availability is a major driver of population dynamics in the tropical north of the state, while weather is more important in the subtropical south. The population dynamics of B. tryoni at sites along the central Queensland coast, where it is assumed that a mix of both weather and host fruit availability drive local populations, were poorly captured by the population model. Field cage results showed that B. tryoni successfully bred during winter in Brisbane, with pupal emergence starting in mid-winter (1st week of August), peaking in early spring (2nd week of September). Trap catch at orchards in Brisbane increased with increasing temperature and fruit availability, but diminished with decreasing temperature and fruit availability. The results suggest that B. tryoni has an optimal climate for population growth in the tropics, but fruit availability for offspring production limits population growth. In the subtropics however, both climate and fruit availability determine the population size. Winter temperatures are marginal for B. tryoni population growth in the subtropics.

As espécies de moscas-das-frutas da família Tephritidae são consideradas importantes pragas da fruticultura mundial por utilizarem vários frutos de valor comercial como substrato para desenvolvimento do seu estágio de larva. O gênero Anastrepha é endêmico do Continente Americano e compreende cerca de 200 espécies descritas, das quais 99 ocorrem no Brasil. Dentre essas espécies, destaca-se a espécie nominal Anastrepha fraterculus (sensu lato), que compreende um complexo de espécies crípticas, quatro das quais foram reconhecidas, até o momento, A. sp.1, A. sp.2 e A. sp.3 (Brasil) e A. sp.4 encontrada no Equador. O presente trabalho buscou a caracterização da variabilidade do espaçador ITS1 do DNA ribossômico de A. sp.1, A. sp.2 e A. sp.3 em amostras populacionais de diversas localidades do Brasil e a análise desse espaçador em amostras de outras regiões das Américas do Sul, Central e México. O ITS1 mostrou ser um marcador bastante útil para análises filogenéticas entre espécies próximas. Os fragmentos amplificados com os iniciadores 18SF e 5.8SR, construídos neste trabalho, continham cerca de 900 pb, não havendo diferenças significativas entre as amostras. Os fragmentos continham uma seqüência parcial do gene 18S, o ITS1 completo e o início do gene 5.8S. O ITS1 variou de 539 a 584 bases. Todos os exemplares apresentaram uma quantidade muito maior de base AT (entre 77,6 a 88,6%). O índice de similaridade entre as amostras variou de 88% a 99,8%. Não foram observadas diferenças significativas intraespecíficas entre as seqüências de amostras populacionais das entidades brasileiras do complexo. A análise filogenética feita pelo programa POY gerou muitas árvores igualmente parcimoniosas. A árvore de consenso estrito agrupou as amostras em clados distintos. O clado (grupo externo) formado por C. capitata e C. rosa foi colocado em um ramo distinto e no outro clado, todas as amostras de Anastrepha. O clado de A. fraterculus, separou as amostras do México e Guatemala das demais, que formaram outro clado. Dentro deste clado, foram formados dois subgrupos, um com as amostras do Peru e Equador e um com as amostras do Brasil e Argentina. Dentro desses clados houve separação em sub-grupos de amostras de cada região geográfica, sendo observada, com algumas exceções uma relação desses grupos com as divisões biogeográficas da entomofauna da América Latina. Desta forma, a análise do ITS1 corrobora resultados anteriores indicando que há claramente três entidades do complexo fraterculus no Brasil (A. sp.1, A. sp.2 e A. sp.3) e que diferentes morfotipos devem existir nas diferentes regiões da América Latina.<br>Fruit flies of Tephritidae family are important pest for the worldwide fruitculture because many species use commercial variety of fruits as host for the development of thier larval stage. Anastrepha is endemic of the American Continent and comprises about 200 described species, 90 of which occurs in Brazil. Among these species the most important is the nominal A. fraterculus, that, actually, comprises a complex of cryptic species, the so-called \"fraterculus complex\". Four species of the complex has been characterized, three of which occurs in Brazil (A.sp.1, A.sp.2, A. sp.3) and one in Ecuador (A. sp.4). In the present analyses the ITS1 spacer of the ribosomal genes was characterized by PCR and sequencing, in samples of A. fraterculus s.l. from several populations in Brazil and from different regions of South, Central America and Mexico. Amplyfication was carried out with primers designed in the present analyses, 18SF and 5.8SR, that generate fragments of 900 bp containing a partial sequence of the 18S gene, the complete ITS1 and the initial portion of the 5.8S gene. The length of the fragment did not varied significantly among the samples. The ITS1 size varied from 539 to 584 bp, and contained a very high content of AT, from 77.6 to 88.6 %, among samples. Similarity of the ITS1 sequences was high (from 88% to 99.8%) among the samples, and no signficant intraspecific differences were found in the sequences of samples from different brazilian populations. The POY software produced many parcimonious phylogenetic trees, and the strict consensus tree grouped the samples in distinct clades. First, there was a separation of the clade of Ceratitis species (outgroups) from the clade of Anastrepha. Within this clade A. obliqua was isolated from a large clade containg all the samples of A. fraterculus s.l.. Within A. fraterculus, one clade grouped the samples from Mexico and Guatemala, another clade the samples from Ecuador and Peru and a clade with the samples from Brazil and Argentina. The sample of Colombia was found as independent branch of the tree. In each of these clades there were subgroups of the different samples, and it was observed a relationship of these clades and subgroups to the biogeographic divisions of the entomofauna of Latin America with a few exceptions. The analysis of ITS1 clearly corroborate previous data indicating that there are three biological entities of the fraterculus complex in Brazil. It also indicates that different entities must exist in other regions of Latin America.

The Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), a major pest of horticulture in eastern Australia, is a relatively poor coloniser of new habitat. This thesis examines behavioural properties that might limit the ability of B. tryoni to establish new populations. As the potential for B. tryoni to establish an outbreak population may be most directly limited by mechanisms associated with dispersal and mating behaviour, these two factors were the focus of this research project. The relevance of dispersal and mating behaviour for control of outbreak populations was assessed. Dispersal (i) Dispersal patterns of males and females are not different. Dispersal of post-teneral male B. tryoni from a point within an orchard near Richmond, New South Wales, was monitored following temporally replicated releases. Application of sterile insect technique (SIT) requires knowledge of dispersal from a release point so that effective release rates can be determined. In addition, dispersal following introduction to new habitat can lead to low or negative population growth and an Allee effect. In Spring and Autumn, 2001 – 2003, three different strains of B. tryoni were released: (1) wild flies reared from infested fruit collected in the Sydney Basin; (2) a laboratory-reared strain with a colour mutation (white marks); and (3) sterile flies obtained by gamma-irradiation of a mass-reared strain. Dispersal was monitored using a grid of traps baited with the male attractant, cuelure. During the majority of releases, flies were massmarked using a self-marking technique and fluorescent pigment powder to enable identification of recaptured flies. A preliminary study found that fluorescent pigment marks had no effect on adult survival and marks did not fade significantly in the laboratory over a period of five weeks after eclosion. As cuelure repels inseminated sexually mature female B. tryoni, unbaited, coloured flat sticky traps, and black and yellow sticky sphere traps baited with a food lure (protein autolysate solution) were used to supplement traps baited with cuelure. The effectiveness of these two sticky trap types was assessed, and recaptures used to compare patterns of dispersal from a release point by male and female B. tryoni. Fluorescent yellow (chartreuse), green, and clear unbaited flat sticky traps were relatively ineffective for monitoring dispersal of sterile male and female B. tryoni, recapturing only 0.1% of released sterile flies. Monitoring dispersal with sticky ball traps baited with protein autolysate solution was more successful, with yellow spheres and black spheres recapturing 1.7% and 1.5%, respectively. Trap colour had no effect on recaptures on flat sticky traps or sticky spheres. Equal recapture rates on yellow and black sticky sphere traps suggests that the odour of yeast autolysate solution was more important than colour for attraction of post-teneral flies to traps. Using the results of recaptures on odoriferous black and yellow sticky sphere traps within one week of release, regression equations of male and female recaptures per trap were found to be similar (Figure 4-3). This is the first study to clearly indicate that post-teneral dispersal patterns of male and female B. tryoni released from a point do not differ, enabling the use of existing models to predict density of both sexes of B. tryoni following post-teneral dispersal. (ii) Males disperse further in Spring than in Autumn, but this is not temperature-related. Analysis of replicated recaptures in traps baited with cuelure revealed that dispersal of male B. tryoni in an orchard near Richmond, New South Wales, was higher in Spring than in Autumn (Figure 5-6). As the maximum daily temperature was significantly higher in Spring than in Autumn this result was unexpected, since earlier studies have found that B. tryoni disperse at the onset of cool weather in search of sheltered over-wintering sites. Dispersal of post-teneral B. tryoni may have been affected by habitat suitability; it was found that seasonal trends in dispersal could have been influenced by local habitat variables. Low mean dispersal distances in Autumn may be explained by the presence of fruiting hosts in the orchard, or the availability of resources required by over-wintering flies. There was no significant correlation between temperature and mean dispersal distance, suggesting that higher rates of dispersal cannot be explained by temperature-related increases in activity. Recapture rate per trap was significantly negatively correlated with increasing daily maximum and average temperature. This may have consequences for detection of B. tryoni outbreaks in quarantine areas due to reduced cuelure trap efficiency. (iii) Maturity and source variation affect dispersal and response to cuelure. This research indicated that most male and female B. tryoni do not disperse far from a release point, suggesting that an invading propagule would not spread far in the first generation. However, there is considerable variation in flight capability among individuals. Comparison of wild, laboratory-reared white marks, and gamma-irradiated sterile male B. tryoni indicated that mean dispersal distance and redistribution patterns were not significantly affected by fly origin. Despite no difference in dispersal distance from the release point, recaptures of wild and sterile males per Lynfield trap baited with cuelure were highest within one week after release, whereas recaptures of white marks males per trap increased in the second week. This result may offer evidence to support the hypothesis that sterile male B. tryoni respond to cuelure at an earlier age. Rearing conditions used to produce large quantities of males for sterilisation by gamma-irradiation may select for earlier sexual maturity. Mating Behaviour (i) Density and sex ratio do not affect mating, except at low densities. Demographic stochasticity in the form of sex ratio fluctuations at low population density can lead to an observed Allee effect. The effect of local group density and sex ratio on mating behaviour and male mating success of a laboratory-adapted strain of B. tryoni was examined in laboratory cages. In the laboratory-adapted strain of B. tryoni used in this study, a group of one female and one male was sufficient for a good chance of mating success. The proportion of females mated and male mating success was not significantly affected by density or sex ratio, although variability in male mating success was higher at low density. This could indicate that mating success of B. tryoni can be reduced when local group density is low owing to decreased frequency in encounters between males and females. (ii) Mass-reared males exhibit aberrant mating behaviour, but this does not reduce mating success. Strong artificial selection in mass-rearing facilities may lead to decreased competitiveness of sterile males released in SIT programs as a result of alteration or loss of ecological and behavioural traits required in the field. The effects of domestication and irradiation on the mating behaviour of males of B. tryoni were investigated by caging wild, mass-reared and sterile (mass-reared and gammairradiated) males with wild females. Mating behaviour of mass-reared males was different from that of wild males, but behaviour of wild and sterile males was similar. Mass-reared males were found to engage in mounting of other males much more frequently than wild and sterile males, and began calling significantly earlier before darkness. Male calling did not appear to be associated with female choice of mating partners, although this does not exclude the possibility that calling is a cue used by females to discriminate between mating partners. Conditions used to domesticate and rear large quantities of B. tryoni for SIT may select for an alternative male mating strategy, with mass-reared males calling earlier and exercising less discrimination between potential mating partners. Despite differences in behaviour of wild, mass-reared and sterile males, frequency of successful copulations and mating success were similar. (iii) Pheromone-calling by males was increased in larger aggregations but this did not result in significantly more female visits. Finally, large laboratory cages with artificial leks were used to investigate the importance in B. tryoni of male group size for female visitation at lek sites and initiation of male pheromone-calling. Calling propensity of male B. tryoni was increased by the presence of conspecific males. Females visited the largest lek more frequently than single males, but there was no correlation between lek size and female visitation. Female B. tryoni had a limited capacity to perceive a difference between the number of calling males; female visitation at leks was only weakly associated with male calling, suggesting that lek size and the number of pheromone-calling males may not be the only factor important in locating mates in B. tryoni. The weak, but positive correlation between male calling and female visitation may indicate that passive attraction maintains lek-mating in B. tryoni. Further studies are essential on mating behaviour of B. tryoni, including identification of male mating aggregations in the field, measurement of habitat variables associated with male aggregations, the influence of density on wild B. tryoni mating success, and the role of pheromone-calling, in order to optimise use of SIT for control of this pest.

The Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera: Tephritidae), a major pest of horticulture in eastern Australia, is a relatively poor coloniser of new habitat. This thesis examines behavioural properties that might limit the ability of B. tryoni to establish new populations. As the potential for B. tryoni to establish an outbreak population may be most directly limited by mechanisms associated with dispersal and mating behaviour, these two factors were the focus of this research project. The relevance of dispersal and mating behaviour for control of outbreak populations was assessed. Dispersal (i) Dispersal patterns of males and females are not different. Dispersal of post-teneral male B. tryoni from a point within an orchard near Richmond, New South Wales, was monitored following temporally replicated releases. Application of sterile insect technique (SIT) requires knowledge of dispersal from a release point so that effective release rates can be determined. In addition, dispersal following introduction to new habitat can lead to low or negative population growth and an Allee effect. In Spring and Autumn, 2001 � 2003, three different strains of B. tryoni were released: (1) wild flies reared from infested fruit collected in the Sydney Basin; (2) a laboratory-reared strain with a colour mutation (white marks); and (3) sterile flies obtained by gamma-irradiation of a mass-reared strain. Dispersal was monitored using a grid of traps baited with the male attractant, cuelure. During the majority of releases, flies were massmarked using a self-marking technique and fluorescent pigment powder to enable identification of recaptured flies. A preliminary study found that fluorescent pigment marks had no effect on adult survival and marks did not fade significantly in the laboratory over a period of five weeks after eclosion. As cuelure repels inseminated sexually mature female B. tryoni, unbaited, coloured flat sticky traps, and black and yellow sticky sphere traps baited with a food lure (protein autolysate solution) were used to supplement traps baited with cuelure. The effectiveness of these two sticky trap types was assessed, and recaptures used to compare patterns of dispersal from a release point by male and female B. tryoni. Fluorescent yellow (chartreuse), green, and clear unbaited flat sticky traps were relatively ineffective for monitoring dispersal of sterile male and female B. tryoni, recapturing only 0.1% of released sterile flies. Monitoring dispersal with sticky ball traps baited with protein autolysate solution was more successful, with yellow spheres and black spheres recapturing 1.7% and 1.5%, respectively. Trap colour had no effect on recaptures on flat sticky traps or sticky spheres. Equal recapture rates on yellow and black sticky sphere traps suggests that the odour of yeast autolysate solution was more important than colour for attraction of post-teneral flies to traps. Using the results of recaptures on odoriferous black and yellow sticky sphere traps within one week of release, regression equations of male and female recaptures per trap were found to be similar (Figure 4-3). This is the first study to clearly indicate that post-teneral dispersal patterns of male and female B. tryoni released from a point do not differ, enabling the use of existing models to predict density of both sexes of B. tryoni following post-teneral dispersal. (ii) Males disperse further in Spring than in Autumn, but this is not temperature-related. Analysis of replicated recaptures in traps baited with cuelure revealed that dispersal of male B. tryoni in an orchard near Richmond, New South Wales, was higher in Spring than in Autumn (Figure 5-6). As the maximum daily temperature was significantly higher in Spring than in Autumn this result was unexpected, since earlier studies have found that B. tryoni disperse at the onset of cool weather in search of sheltered over-wintering sites. Dispersal of post-teneral B. tryoni may have been affected by habitat suitability; it was found that seasonal trends in dispersal could have been influenced by local habitat variables. Low mean dispersal distances in Autumn may be explained by the presence of fruiting hosts in the orchard, or the availability of resources required by over-wintering flies. There was no significant correlation between temperature and mean dispersal distance, suggesting that higher rates of dispersal cannot be explained by temperature-related increases in activity. Recapture rate per trap was significantly negatively correlated with increasing daily maximum and average temperature. This may have consequences for detection of B. tryoni outbreaks in quarantine areas due to reduced cuelure trap efficiency. (iii) Maturity and source variation affect dispersal and response to cuelure. This research indicated that most male and female B. tryoni do not disperse far from a release point, suggesting that an invading propagule would not spread far in the first generation. However, there is considerable variation in flight capability among individuals. Comparison of wild, laboratory-reared white marks, and gamma-irradiated sterile male B. tryoni indicated that mean dispersal distance and redistribution patterns were not significantly affected by fly origin. Despite no difference in dispersal distance from the release point, recaptures of wild and sterile males per Lynfield trap baited with cuelure were highest within one week after release, whereas recaptures of white marks males per trap increased in the second week. This result may offer evidence to support the hypothesis that sterile male B. tryoni respond to cuelure at an earlier age. Rearing conditions used to produce large quantities of males for sterilisation by gamma-irradiation may select for earlier sexual maturity. Mating Behaviour (i) Density and sex ratio do not affect mating, except at low densities. Demographic stochasticity in the form of sex ratio fluctuations at low population density can lead to an observed Allee effect. The effect of local group density and sex ratio on mating behaviour and male mating success of a laboratory-adapted strain of B. tryoni was examined in laboratory cages. In the laboratory-adapted strain of B. tryoni used in this study, a group of one female and one male was sufficient for a good chance of mating success. The proportion of females mated and male mating success was not significantly affected by density or sex ratio, although variability in male mating success was higher at low density. This could indicate that mating success of B. tryoni can be reduced when local group density is low owing to decreased frequency in encounters between males and females. (ii) Mass-reared males exhibit aberrant mating behaviour, but this does not reduce mating success. Strong artificial selection in mass-rearing facilities may lead to decreased competitiveness of sterile males released in SIT programs as a result of alteration or loss of ecological and behavioural traits required in the field. The effects of domestication and irradiation on the mating behaviour of males of B. tryoni were investigated by caging wild, mass-reared and sterile (mass-reared and gammairradiated) males with wild females. Mating behaviour of mass-reared males was different from that of wild males, but behaviour of wild and sterile males was similar. Mass-reared males were found to engage in mounting of other males much more frequently than wild and sterile males, and began calling significantly earlier before darkness. Male calling did not appear to be associated with female choice of mating partners, although this does not exclude the possibility that calling is a cue used by females to discriminate between mating partners. Conditions used to domesticate and rear large quantities of B. tryoni for SIT may select for an alternative male mating strategy, with mass-reared males calling earlier and exercising less discrimination between potential mating partners. Despite differences in behaviour of wild, mass-reared and sterile males, frequency of successful copulations and mating success were similar. (iii) Pheromone-calling by males was increased in larger aggregations but this did not result in significantly more female visits. Finally, large laboratory cages with artificial leks were used to investigate the importance in B. tryoni of male group size for female visitation at lek sites and initiation of male pheromone-calling. Calling propensity of male B. tryoni was increased by the presence of conspecific males. Females visited the largest lek more frequently than single males, but there was no correlation between lek size and female visitation. Female B. tryoni had a limited capacity to perceive a difference between the number of calling males; female visitation at leks was only weakly associated with male calling, suggesting that lek size and the number of pheromone-calling males may not be the only factor important in locating mates in B. tryoni. The weak, but positive correlation between male calling and female visitation may indicate that passive attraction maintains lek-mating in B. tryoni. Further studies are essential on mating behaviour of B. tryoni, including identification of male mating aggregations in the field, measurement of habitat variables associated with male aggregations, the influence of density on wild B. tryoni mating success, and the role of pheromone-calling, in order to optimise use of SIT for control of this pest.

Orientadores: Benedito Carlos Benedetti, Adalton Raga, Perla Gómez Di Marco<br>Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola<br>Made available in DSpace on 2018-08-17T18:23:01Z (GMT). No. of bitstreams: 1 Vieira_StellaMariaJanuaria_D.pdf: 942200 bytes, checksum: f0c6adbea884bee20c024b9044a05cb9 (MD5) Previous issue date: 2011<br>Resumo: A goiaba é um fruto com boas características organolépticas e nutricionais, além de ter boa aceitação tanto para o consumo "in natura" como industrial. É, porém, bastante perecível após a colheita, daí decorrendo perdas significativas. Além disso, acaba destinada quase totalmente ao mercado interno, em virtude das barreiras fitossanitárias impostas por países importadores diante de problemas como a infestação por moscas-das-frutas. É exatamente no estudo dessa praga que se situa o objeto do presente trabalho, cuja realização obedeceu aos seguintes propósitos: 1) avaliar a eficiência dos métodos de controle de radiação "UVC"e "água quente", bem como a aplicação combinada de ambos, para o fim de promover a desinfestação de ovos de Ceratitis capitata (Wied.) (Diptera: Tephritidae) em goiabas 'Kumagai'; 2) avaliar a qualidade físico-química de goiabas 'Kumagai' submetidas aos tratamentos quarentenários. No que se refere ao método "água quente", o equipamento banho-maria Dubnoff existente em laboratório forneceu uma variação de temperatura de 0,5 ºC, sendo que as médias dos tempos de exposição, verificados em termopares inseridos a 5 mm, para as temperaturas avaliadas de 42,0 a 50,0 ºC (± 0,5) com intervalos de 1,0 ºC, foram menores que as médias dos tempos de exposição daqueles termopares inseridos no centro das goiabas para as mesmas temperaturas avaliadas. Em função desse aumento no tempo de imersão em altas temperaturas, foram observadas a presença de escaldaduras na casca das goiabas tratadas a 46,0; 47,0; 48,0; 49,0 e 50,0 ºC (± 0,5). Por sua vez, no que tange ao método por "UV-C", as lâmpadas utilizadas no equipamento de radiação possuíam comprimentos de onda predominantes de 254 nm (adequados, portanto, para o estudo de radiação UV-C) e a tela de aço (diâmetro da malha hexagonal: 6,0x 7,0 cm) foi o material escolhido para compor a prateleira central, distante 8 cm da fonte luminosa. Aplicados os métodos em questão, o que se observou nos testes "in vitro" foi que ampliação do tempo de imersão no tratamento hidrotérmico e a exposição a intensidades crescentes de radiação UV-C no tratamento por radiação conduziram a um aumento na mortalidade ovos de C. capitata; já quanto aos testes "in vivo", a conclusão, em relação ao método "água quente", foi a de que tratamentos a temperaturas de 46,0; 47,0; 48,0; 49,0 e 50,0 (± 0,5) ºC, com tempos de imersão de 0; 46; 36; 26; 16 e 12 minutos, respectivamente, são eficientes para a mortalidade de ovos de C. capitata (não tendo sido verificadas escaldaduras nas cascas das frutas às temperaturas avaliadas) e, em relação ao método "UV-C", verificou-se que a intensidade de 16,0 kJm-2 foi capaz de inativar 100% de ovos de C. capitata. Nos tratamentos combinados, foi observado efeito aditivo na mortalidade de ovos de C. capitata, sendo mais intensos nas combinações de 0,54 kJm-2 + 45,0 ± 0,5 ºC; 0,80 kJm-2 + 45,0 ± 0,5 ºC; 0,54 kJm-2 + 46,0 ± 0,5 ºC e 0,80 kJm-2 + 46,0 ± 0,5 ºC. Por fim, quanto à qualidade pós-colheita, a das goiabas submetidas aos tratamentos e armazenadas a 8,0 ± 0,2 ºC durante o período de armazenamento de 10 dias mostrou-se superior à das goiabas que tiveram aplicados os mesmos tratamentos e foram armazenadas a 22,0 ± 0,2 ºC<br>Abstract: Guava is a fruit that has good organoleptic and nutritional haracteristics, besides having a good acceptance as for consumption "in natura" as industrial. It is, however, a lot perishable after the harvest, and because of that there are countless losses to the producers. Besides it, the fruit is practically consumed in the internal market, because of the sanitary obstacles imposed by importing countries before matters as infestation by fruit flies. It is exactly in the study of this plague that is the object of this work whose achievement has obeyed the following steps: 1) evaluating the efficiency of hot water imersion, UV-C radiation methods, and the application in both, with the intention of promoting the not infestation of eggs of Ceratitis capitata (Wied.) (Diptera: Tephrittidae) in "Kumagai" guavas; 2) evaluating the physics-chemistry quality submitted to quarantine treatments. Mentioning to the method hot water, the double boiler Duboff equipment existing in the laboratory gives us a variation of temperature of 0,5 ºC, as for the average of times of expositions verified in pairs at 5 mm, for temperatures of 42,0 the 50,0 ºC (± 0,5) with intervals of 1,0 ºC was lower than the ones of the times in exposition in the center of guavas to the same temperatures. Due to this increase of the time of immersion in high temperatures, it was noticed the presence of burns on the treated guavas peel to 46,0; 47,0; 48,0; 49,0 and 50,0 ºC (± 0,5). By its shift, according to the UV-C method, the light bulbs used in the radiation equipment had 254 nm waves (proper to the study of radiation UV-C) and the steel screen (hexagonal mesh: 6,0 x 7,0 cm) was the chosen material to compose the central shelf, far 8 cm from the illuminated fountain. The used methods, what was noticed in the tests "in vitro" was that the amplification of the time of the immersion (in the hydrothermical) and the exposition to the increasing intensity of radiation UV-C (in the treatment by radiation) led to an increase in the mortality of eggs of C. capitata; according to the tests "in vivo" the conclusion in relation to the method hot water was that treatments to the temperatures 46,0; 47,0; 48,0; 49,0 e 50,0 ºC (± 0,5). With times of immersion of 46; 36; 26; 16 and 12 minutes, respectively, are efficient to the mortality of the eggs of C. capitata (not having being verified burns on the fruits peel to the evaluated temperatures) and, in relation to the method UV-C, it was noticed that the intensity of 16.0 kJm-2 was able to activate 100% of eggs of C. capitata. In the combined treatments, it was observed the adding effect in the mortality of eggs of C. capitata, being more intense in the combinations 0,54 kJm-2 + 45,0 ± 0,5 ºC; 0,80 kJm-2 + 45,0 ± 0,5 ºC; 0,54 kJm-2 + 46,0 ± 0,5 ºC e 0,80 kJm-2 + 46,0 ± 0,5 ºC. Finally according to the quality after the harvest, the guavas that were submitted to the treatment and stored to 8,0 ± 0,2 ºC during a period of 10 days were superior to the guavas that had the same treatments and were stored to 22,0 ± 0,2 ºC<br>Doutorado<br>Tecnologia Pós-Colheita<br>Doutor em Engenharia Agrícola

Made available in DSpace on 2016-12-08T16:44:32Z (GMT). No. of bitstreams: 1 PGPV09MA025.pdf: 1332630 bytes, checksum: d4dcb0a524aaa8a52524e31392a208e0 (MD5) Previous issue date: 2009-09-18<br>The cultivation of apple tree is the main activity from the mountain region of Santa Catarina, in Brazil. The fruit fly Anastrepha fraterculus (Wiedmann, 1830) (Diptera: Tephritidae) is the main pest from this culture being of difficult control, compromising the quality of fruits. Field and laboratory experiments were conducted with the objective of testing alternative methods to the management and control of the fruit fly. The tests involved the attractiveness efficiency of commercial food-based baits; the action of floristic localization and vegetation near the orchards, the efficiency of different material to bagging the fruits and also the action of phytotherapic and biotherapic preparations on adults of A. fraterculus. The efficiency of grape juice (25%), BioAnastrepha® hydrolyzed protein (5%), Isca Mosca® protein (5%) and Torula yeast (2.5%) was tested using McPhail traps placed on the external branches at 1.8 m high from soil and 50 m distant from each trap. In three orchards with different geographic localization it was realized the floristic survey from the surrounding area and monitoring of population fluctuation of the fruit fly by using traps containing grape juice at 25% placed at the orchards edges. Fuji suprema and Imperial gala had their fruits bagged with micro-perforated plastic bags made of non-textured fabric. At harvest time, the damage caused by the pest, disease incidence and the effect of bagging on the physicochemical quality of fruits were evaluated. In laboratory, the effect of phytotherapic and biotherapic preparations on the biology of the fruit fly was also tested. Healthy fruits treated with different preparations were offered to fruit fly adults for 48 hours. Seven days after infestation, the number of pupae and emerged adults was evaluated for 30 days. All the trials were carried out in randomized blocks during the crop seasons of 2007/08 and 2008/09. BioAnastrepha® hydrolyzed protein (5%) was the substance that attracted the highest number of A. fraterculus adults. Geographic position and floristic composition in the surrounding region affected population fluctuation of the fruit fly. The orchard located at 1,415 m of altitude and surrounded by commercial orchards constituted of host plants and the one located at 1,228 m of altitude surrounded by native forest were the ones the showed smaller population of flies. Bagging protected fruits from damage of A. fraterculus, Grapholita molesta, Bonagota salubricola, but did not protect against pathogens that cause apple scab and moldy core. Bagging of Imperial gala&#8223; fruits accelerated maturation process while for Fuji suprema&#8223; fruits it reduced the red color in fruits and calcium accumulation. The biotherapic preparation with Cinnamon at 6CH showed repellence effect on A. fraterculus adults. It was concluded that the management of A. fraterculus can be done by using ways alternative to pesticides, so that the contamination risk of the fruits and the environment, and even intoxication of the farmers can be reduced<br>O cultivo da macieira é a principal atividade da região serrana catarinense. A mosca-das-frutas Anastrepha fraterculus (Wiedmann, 1830) (Diptera: Tephritidae) é a principal praga desta cultura sendo de difícil controle e comprometendo a qualidade dos frutos. Com o objetivo de testar métodos alternativos para o manejo e controle da mosca-das-frutas, foram realizados experimentos a campo e em laboratório. Testou-se: a eficiência atrativa de substâncias alimentares comerciais; a ação da localização e da composição floristica do entorno dos pomares; a eficiência de diferentes materiais para o ensacamento de frutos e a influência destes materiais sobre a qualidade físico-quimica das frutas e a ação de preparados fitoterápicos e homeopáticos sobre adultos de A. fraterculus. Utilizando armadilhas, modelo McPhail, instaladas a 1, 80 m do solo e distribuídas nas linhas de plantas em intervalos de 50 m, foi testado a eficiência de suco de uva 25%, de proteína hidrolisada BioAnastrepha 5%, de proteína hidrolisada Isca Mosca 5% e da levedura torula 2,5%. Em três pomares com diferentes localizações geográficas foi realizado o levantamento florístico do entorno e o acompanhamento da flutuação populacional da mosca-das-frutas através de armadilhas contendo solução de suco de uva a 25%, instaladas nas plantas das bordas dos pomares. Frutos das cultivares Fuji Suprema&#8223; e Imperial Gala&#8223; foram ensacados com sacos plásticos micro-perfurados ede tecido não texturizado (TNT). Na época da colheita foi avaliado o dano causado por insetos praga, a incidência de doenças e o efeito do ensacamento sobre a qualidade físico-química dos frutos. No laboratório testou-se o efeito de preparados fitoterápicos e homeopáticos sobre a biologia da mosca-das-frutas. Frutos sadios e tratados com os diferentes preparados foram oferecidos aos adultos da mosca-das-frutas por um período de 48 horas. Aos sete dias após a infestação, durante 30 dias, avaliou-se o número de pupas e adultos emergidos. Todos os experimentos foram conduzidos em blocos ao acaso durante as safras de 2007-08 e 2008-09. A proteína hidrolisada BioAnastrepha 5% foi a substância que atraiu maior número de adultos de A. fraterculus. A posição geográfica do pomar e composição florística de seu entorno afetaram a flutuação populacional da mosca-das-frutas. O pomar localizado a 1.415 metros de altitude e circundado por pomares comerciais constituídos por plantas hospedeiras e aquele localizado a altitude de 1.228 circundado por mata nativa, foram os que apresentaram menor população de moscas. O ensacamento protegeu os frutos dos danos de A. fraterculus, Grapholita molesta, Bonagota salubricola, mas não protegeu contra patógenos causadores da sarna da macieira e podridão carpelar. O ensacamento de frutos de maçã Imperial Gala&#8223; acelerou o processo de maturação nos frutos, enquanto nos frutos de maçã Fuji Suprema&#8223; o ensacamento diminuiu a coloração vermelha dos frutos em ambas as safras e aumentou o acúmulo de cálcio na safra 2008/09. O preparado homeopático Cinamomo na potência 6CH mostrou efeito de repelência sobre adultos de A. fraterculus. Conclui-se que o manejo de A. fraterculus pode ser realizado com uso de medidas alternativas aos agrotóxicos reduzindo desta forma o risco de contaminação dos frutos e do meio ambiente e de intoxicação dos agricultores

Ceratitis capitata Wiedemann (Diptera: Tephritidae) is a cosmopolitan pest, originary from West-Africa, that has invaded almost all the temperate and tropical countries by the unwanted aid of the men. During its adaptation to these new environments, C. capitata has widened its host plant portfolio, being nowadays a key pest for more than 400 plant species of economic importance. Due to this importance, many importing countries had established quarantine measures and borders against fruit world-wide trade, which had directly impacted on the plant protection policies of producer countries. Spain and Tunisia are located in the Mediterranean basin; the first known world-wide dispersal point of C. capitata. In these two countries, C. capitata is considered a key pest mainly for citrus species and other soft-fruits. From a historical point of view, Plant Protection policies in Spain were switched from a nearly ecological management (with great losses) to mainly chemical-based treatments with the spread of organosphosphate compounds early on XX century. With the development of European Union, national Plant Protection plans were modified, introducing the Integrated Pest Management programs (IPM), on which environment and human-friendly methods should be selected instead of the most damaging chemical treatments. Following these steps, Tunisia is integrating the use of biorrational methods while keeping the use of chemicals as low as possible. To this end, in the present thesis dissertation, I would focus on the use of natural enemies as the best and sustainable control method, coming back to the Biological Control programs that were successful in the past against other pests in both countries. More precisely, this dissertation is presenting the results on the implementation of Classical Biological Control against C. capitata in citrus, by the importation, evaluation and release of the parasitoid species Diachasmimorpha longicaudata (Ashmead) (Hymenoptera: Braconidae) in both countries. This parasitoid species, native from East Asia, is currently used against other tephritid pest species, key species for other countries and commodities. In the First Chapter I will present a literature review on the Plant protection policies against this key pest, and what is know about the performance and success of this parasitoid species. At the Second Chaper, I will present the results of the implementation of laboratory rearings of both insects to achieve all the remaining objectives, along with the determination of life parameters of the specie that will determine its success as natural enemy. In this second chapter I will also present the determination of biotic (host densities and availability) and abiotic (temperature, RH, rainfall) factors affecting the performance of D. longicaudata over C. capitata. During the Third Chapter, I will demonstrate that D. longicaudata is able to exhert control of C. capitata under natural Mediterranean climatic conditions when either challenging the parasitoid with hosts directly from the laboratory rearing or in a more natural condition, within the fruits, a forestep required to determine its inclusion in the national Plant Protection Policies. Results show that D. longicaudata exhert up to 30% of medfly population reduction by means of induced mortality along the provisioning of new parasitoid offspring that would propagate and establish in the country. Along these results I showed that D. longicaudata was able to control medfly infestation foci at a rate that depend on climatic conditions and on the number of released females. At the Fourth Chapter, I will reveal the results of D. longicaudata dispersion abilities along its capability to exhert control of C. capitata populations while applied joinly with SIT, by means of open-field test trials, with a new developed sentinel fruits methodology. In this chapter, I consider also the abiotic factors that could determine its naturalization in other Mediterranean countries with similar climatic conditions. The results of this chapter highlight the need of such dispersal studies at the corresponding local climatic conditions to establish the release procedures. At the Fifth Chapter, I will expose the results of importation and naturalization of D. longicaudata in Tunisia, with the required studies on the presence of native enemies and the identification of a new parasitoid Pachycrepoideus vindemmiae Rondani (Hymenoptera: Pteromalidae)., the establishment of laboratory rearings for the release trials, and the side-effects of the available control measures that will face D. longicaudata in Tunisian citrus orchards which will determine the procedure in tempo and form for the releases. At the end of this dissertation, I will present the main conclusions achieved that can be summarized in: (i) D. longicaudata is a viable natural enemy that can be successfully released in Mediterranean countries against C. capitata; (ii) Its biotic potential under the mild climatic conditions identified will help in the naturalization of this species, and in the establishment of release protocols, but also, (iii) its climatic requirements highlight the need of switching from Classical Biological Control to Inoculative Biological control, that means that both countries require mass-rearing facilities to provide these insects, along the involvement of growers in the application of IPM measures including the augmentoriums to facilitate the naturalization of the introduced species along the preservation of the native ones.

O complexo de espécies crípticas de Anastrepha fraterculus compreende oito morfotipos dos quais três ocorrem no Brasil. Anastrepha sp.1 aff. fraterculus é o morfotipo Brasil-1 e é uma espécie de ampla distribuição no planalto sudeste/sul do Brasil e no norte da Argentina. O comportamento reprodutivo dessa espécie é complexo, envolvendo uma série de movimentos desempenhados pelos machos para atrair as fêmeas para acasalamento, e ocorre, preferencialmente, nas primeiras horas do dia. Dois genes, period e fruitless, entre outros, são conhecidos por participar do controle do comportamento reprodutivo de vários organismos, incluindo algumas espécies de moscas-das-frutas. O presente trabalho buscou informações sobre a atuação desses genes no comportamento reprodutivo de A. sp.1, utilizando o silenciamento transitório desses genes pela metodologia de RNA interferente. Foram, primeiramente, desenhados iniciadores específicos para amplificar fragmentos do DNA genômico desses genes, sendo demonstrado que apresentaram uma similaridade entre 97 a 99% com os genes equivalentes de outras espécies de Anastrepha. A seguir, após padronização e adaptação de protocolos, foram sintetizados os RNA de dupla-fita (dsRNA) dos dois genes, que foram, então, utilizados nos experimentos de silenciamento. Análises, para verificação se os genes foram realmente silenciados foram feitas a partir a injeção dos dsRNAfru e/ou dsRNAper no abdomên de machos sexualmente maduros, tendo sido demonstrado que os genes estavam silenciados ao máximo, sete a oito dias após a injeção. Interferências no comportamento de machos sexualmente maduros, com um ou outro gene silenciado, foram avaliados por testes relacionados com dois parâmetros do comportamento reprodutivo: alterações nas atividades gerais (qualquer tipo de movimentação dos insetos) dos machos durante o ciclo circadiano (dia/noite) e mais especificamente, a atividade relacionada ao comportamento reprodutivo. Ao injetar dsRNAfru em machos adultos de A. sp.1 foi observado que não houve alteração significativa nas suas atividades gerais. Porém, foi observado que houve uma diminuição significativa no número de machos que realizavam atividades reprodutivas, sugerindo que o silenciamento de fruitless no macho adulto altera o funcionamento normal do comportamento sexual masculino. Em contrapartida, ao injetar dsRNAper em machos adultos de A. sp.1 não foi observada alteração significativa tanto nas suas atividades reprodutivas quanto nas atividades gerais. O silenciamento dos genes aparentemente não afeta a produção de espermatozóides. Apesar de controverso, esses dados corroboram com o que foi observado em D. melanogaster, em que o mutante nulo per04 não apresenta alteração significativa nos seus comportamentos em relação aos machos selavagens em um regime cíclico Dia/Noite. Dessa forma, análises adicionais serão necessárias com o objetivo de elucidar as implicações desses dois genes no comportamento locomotor e reprodutivo de Anastrepha sp.1 aff. fraterculus.<br>The complex of cryptic species Anastrepha fraterculus comprises eight morphotypes three of which occur in Brazil. Anastrepha sp.1 aff. fraterculus correspond to the morphotype Brazil-1 and is a species of wide distribution in the southeast/south plateau of Brazil and in north of Argentina. The reproductive behavior of this species is complex, involving a series of movements performed by males to attract females for mating, and occurs in the early hours of the day. Two genes, period and fruitless, among others, are known to participate in the control of reproductive behavior of various organisms, including some species of fruit flies. The present work aimed to get information about the presumable role of these genes in the reproductive behavior of A. sp.1, using transient silencing of these genes by interfering RNA methodology. Specific primers were first designed to amplify fragments of the genomic DNA of these genes, showing they have a similarity between 97 to 99% with the equivalent genes of other Anastrepha species. After standardization and adaptation of protocols, the double-stranded RNA (dsRNA) of the two genes were synthesized, and used in the silencing experiments. Tests to verify that the genes were actually silenced, were made after injection of the dsRNAfru and/or dsRNAper into the abdomens of sexually mature males. These tests showed that the genes were silenced to the maximum, seven to eight days after the injection. Interferences in the behavior of sexually mature males with one or other silenced gene were evaluated by tests related to two parameters of reproductive behavior: changes in the general activities (any type of movement of insects) of males during the circadian cycle (day/night) and more specifically, activity related to reproductive behavior. Injection of dsRNAfru in adult males of A. sp.1 showed that they did not cause significant alterations in general activities, but it was observed that they cause a significant decrease in the number of males that performed reproductive activities, suggesting that silencing of fruitless. alters the normal functioning of male sexual behavior. In contrast, when injecting dsRNAper. in adult males of A. sp.1, no significant alteration was observed neither in their reproductive activities nor in their general activities. Moreover, silencing of the genes seems not to affect the production of spermatozoa. Although controversial, the data are in line with observations in D. melanogaster, in which the null mutant per04 did not present significant alterations in behaviors relatives to the control males in a Day/Night cyclic regime. Thus, additional analyzes will be needed to elucidate the participation of the two genes in the coordination of behaviors in Anastrepha sp.1 aff fraterculus.

Thesis (Ph. D.)--University of California, Davis, 2009.<br>Title based on PDF title page (viewed 06/18/2010). Degree granted in Agricultural and Resource Economics. Includes bibliographical references.

Queensland fruit fly (Bactrocera tryoni) (QFly) is one of Australia’s most problematic horticultural pests. Key pesticides traditionally used to manage the pest, fenthion and dimethoate, have recently been restricted, resulting in area-wide management (AWM) of QFly becoming a key recommended practice. AWM involves management of the entire pest population by coordinating management strategies across all key pest sources throughout a geographical region. If successful, AWM requires fewer pesticides than traditional farm-by-farm approaches as it reduces the overall pest pressure in a region. It can potentially contribute to supporting market access to QFly-sensitive markets. Success depends on achieving and maintaining cooperation between a critical mass of landholders with QFly hosts on their land as unmanaged hosts provide breeding places for QFly. The increased push for AWM coincides with state governments tending to reduce direct on-ground support for pest management. It is increasingly up to local industries to take the reins of implementing AWM programs. A considerable literature about AWM is available, but it focuses mainly on technical and economic aspects. This research investigated the social and institutional aspects of industry-driven AWM programs based on two research questions: (1) What social and institutional factors influence the success of industry-driven AWM at the local level and how can success be maximised?; and (2) What are the main constraints to an enabling environment for industry-driven AWM implementation and how can these be mitigated? Three case studies, together with literature about socio-ecological systems, were explored to answer question 1. This involved 43 semi-structured interviews, three focus groups and a grower survey involving 98 respondents across the cases. Question 2 was answered based on 33 semi-structured interviews with people operating in the broader QFly management innovation system, representing the technological, institutional, organisational and operational aspects of the QFly domain. These findings together with the grower survey results were analysed through the lens of Agricultural Innovation Systems thinking. The research found that the feasibility of industry-driven AWM depends on factors at the local level and within the broader QFly management innovation system. Locally, a social profile favourable to AWM includes a relatively homogenous grower community; high levels of social capital; existing opportunities to monitor compliance; and a high ratio between those who have an incentive to manage QFly and those who do not. As every region is unique, AWM is best approached through adaptive co-management to bolster local QFly knowledge and support a common narrative and adaptive capacity. This involves ‘learning by doing’ and drawing on different knowledge systems including QFly biology and behaviour; market access; community engagement; and different forms of local knowledge. Market access requirements are best seen as ‘bolt-on’ components. To carry out adaptive co-management, local industries need to be able to readily access the needed knowledge, capabilities and resources. The broader QFly management innovation system needs to be responsive to meeting these needs. Training for key local stakeholders can assist in overcoming limited local capacities. This work found that in the multi-level biosecurity world, the local level can easily become disconnected. Knowledge brokers and interconnected innovation platforms can ensure strong two-way information flow between local programs and other players, such as policy-makers, researchers and market access personnel. Other key difficulties to local industries include the reliance on voluntary approaches for securing wide-spread support and establishing a sustainable income. Complementary policy mechanisms tailored to local conditions to back-up industry-driven approaches are recommended. This research makes an important contribution to successful future QFly management by complementing prevailing high investment in improving QFly management technologies.

Cette recherche a été réalisée grâce à l'aide financière du Programme Innov'action agroalimentaire de l'entente Cultivons l'Avenir 2 conclue entre le Ministère de l'Agriculture, des Pêcheries et de l'Alimentation du Québec (MAPAQ) et Agriculture et Agri-Food Canada.<br>La drosophile à ailes tachetées s’avère être un ravageur exotique particulièrement dommageable pour les cultures de petits fruits puisqu’elle s’attaque aux fruits en murissement. Depuis son invasion des continents américain et européen en 2008, ses populations sont contrôlées majoritairement avec des insecticides chimiques. L’objectif de cette étude était d’explorer le potentiel de la technique des insectes stériles (TIS) comme approche de lutte à la drosophile à ailes tachetées, d’abord en irradiant des pupes à différentes doses pour identifier la dose optimale pour la stérilisation des mâles et, par la suite, en évaluant les capacités reproductives de ces mâles irradiés. En premier lieu, il a été observé que l’irradiation n’avait pas d’effet significatif sur l’émergence, la malformation et la longévité des adultes à chacune des doses testées. Suite à l’accouplement de mâles irradiés avec des femelles saines, deux équations ont été obtenues permettant d’établir une relation entre la dose d’irradiation et un taux d’éclosion des œufs et leur survie jusqu’au stade adulte. Ces résultats ont permis de choisir la dose de 120 Gy comme dose d’irradiation pour la drosophile à ailes tachetées dans un contexte de TIS. Les capacités reproductives des mâles irradiés à cette dose ont ensuite été comparées à celles des mâles non-irradiés. Les mâles irradiés se sont révélés significativement aussi efficaces que les mâles non-irradiés pour accoupler et transmettre du sperme aux femelles en absence de compétition. En conditions de compétition, le succès d’accouplement par le mâle irradié a été de 37,5% et de 62,5% par le mâle non-irradié, mais sans différence significative. Puis, une expérience sur le ré-accouplement des femelles a conclu que celui-ci était peu fréquent et n’était pas influencé significativement par l’irradiation des mâles.<br>Spotted wing drosophila is an exotic pest especially damaging to berry crops because of its ability to lay eggs inside ripening fruits. Since its invasion of North America and Europe in 2008, its populations are controlled mainly with chemical insecticides. The objective of this study was to explore the potential of the sterile insect technique (SIT) as a control method for the spotted wing drosophila, first by irradiating pupae at different doses to identify the optimum dose for male sterilization, and secondly by evaluating the reproductive capacities of these irradiated males. First, it was observed that irradiation had no significant effect on emergence, malformation and longevity of adults at any of the doses tested. Following mating of irradiated males with healthy females, two equations were obtained to establish a relation between the irradiation dose and the egg hatch rate, and the survival rate to the adult stage. These results made it possible to choose the dose of 120 Gy as the irradiation dose for the spotted wing drosophila in an SIT context. The reproductive capacities of males irradiated at this dose were later compared with those of non-irradiated males. Irradiated males were shown to be significantly as effective as non-irradiated males to mate and transfer sperm to females in absence of competition. In competitive conditions however, the success of irradiated males was of 37.5% and of 62.5% for the non-irradiated males, but without significant difference. Then, an experiment on the re-mating of the females concluded that it was infrequent and was not significantly influenced by the irradiation of the males.