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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Padronização de técnica para produção em massa de \'Culex quinquefasciatus\' (Diptera: Culicidae) / Standardization of technique for mass production of Culex quinquefasciatus (Diptera: Culicidae)

Marco Jacometto Marchi 25 February 2014 (has links)
Objetivo - Estabelecer um método para produção em massa do mosquito Culex (Culex) quinquefasciatus em laboratório, com o intuito de fornecer subsídio ao controle populacional desta espécie por meio da liberação de machos estéreis. Métodos Foi fundada uma colônia de Cx. quinquefasciatus a partir de imaturos coletados em janeiro de 2013 no rio Pinheiros, São Paulo/SP, Brasil. Os mosquitos adultos tiveram seus pesos secos mensurados e o desenvolvimento avaliado como o tempo para atingirem o estágio de pupa e a fase adulta. No primeiro experimento foram testadas quatro dietas diferentes (ração de peixe, ração canina, mistura de 50 por cento de ração de peixe e 50 por cento de ração canina ou uma mistura de 33,33 por cento de ração de peixe, 33,33 por cento de ração canina e 33,33 por cento de leite em pó) e três temperaturas (27 ± 2°C, 23 ± 2°C e 20 ± 2°C). No segundo experimento testaram-se diferentes quantidades de ração de peixe, densidades larvárias, volume e altura da coluna dágua Resultados - No primeiro experimento não houve diferença estatística significante entre as quatro dietas testadas e o tempo de formação até a fase de pupas e para o peso seco dos adultos. No entanto a ração de peixe proporcionou a menor mortalidade. A maior temperatura (27 ± 2°C) diminuiu o tempo do ciclo de vida dos imaturos, porém gerou adultos com pesos secos menores. No segundo experimento, a condição 0,5 mg/larva, 5 ml/larva em 2,1 cm de coluna dágua e a 27 ± 2°C ofereceu boa produção em massa e gerou maiores taxas de desenvolvimento, menor mortalidade de imaturos e maior peso seco em adultos. Conclusão - Não foi definida uma dieta ideal para uso na produção em massa, considerando os parâmetros analisados. A dieta menos custosa é a ração canina, porém deve ser moída manualmente ou em máquina, tornando a ração de peixe mais eficiente para ser diretamente aplicada nas bandejas de produção. O estudo sugere que a melhor condição para a produção massa do Cx. quinquefasciatus foi 0,5 mg de ração de peixe/dia por larva num volume de 5 ml/larva em 2,1 cm de coluna dágua e a 27 ± 2°C. O estudo sugere que esta técnica pode auxiliar no controle populacional dessa espécie / Objective To establish a method for mass rearing of Culex (Culex) quinquefasciatus mosquitoes in laboratory, in order to provide subsidy to the population control of this species through the release of sterile males. Methods - A colony of Cx. quinquefasciatus was founded from immature collected in January 2013 in the Pinheiros River, São Paulo/SP, Brazil. Adult mosquitoes had their dry weights measured and the development was evaluated as the time to reach pupae and adult phase. In the first experiment it was tested four different diets (fish food, dog food, a mix of 50 percent fish and 50 percent dog food or a mix of 33.33 percent fish 33.33 percent dog food and 33.33 percent milk powder) and three temperatures (27 ± 2°C, 23 ± 2°C and 20 ± 2°C). In the second experiment it was tested several conditions of food amounts (mg/day), larvae densities (ml of water/larva) and water column height that would generate high development rate, low immature mortality and high adult dry weight. Results - In the first experiment there was no statistically significant difference in the time for the development to pupae stage or in the total dry weight of adults among the four experimental diets. However, fish food provided less immature mortality. The highest temperature (27 ± 2°C) decreased the time of the immature life cycle, but generated adults with lower dry weights. In the second experiment, the condition 0.5 mg/larva, 5 ml/larva in 2.1 cm of water column and 27 ± 2°C offered good mass rearing and generated higher development rate, lower immature mortality and higher adult dry weights. Conclusion No ideal diet was defined for mass rearing in the parameters analyzed. The less expensive diet was the dog food, but this should be milled by hand or machine, which makes the fish food more practical in the production trays. This study suggested that the best condition for mass rearing of Cx. quinquefasciatus mosquitoes was 0.5 mg of daily fish food/larva, 5 ml/larva in 2.1 cm of water column and 27 ± 2°C. The study suggests that this technique can assist in population control of this species
12

Biological studies on the lepidopteran egg parasitoid Trichogrammatoidea lutea Girault (Hymenoptera : Trichogrammatoidae) at various temperatures

Mawela, Khethani Vincent 16 May 2011 (has links)
The African bollworm, Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae), is a polyphagous pest that attacks many crops in sub-Saharan Africa. The pest is currently managed through chemical control, and by planting Bt-transgenic cotton. Trichogrammatoidea lutea Girault (Hymenoptera: Trichogrammatidae) is an indigenous egg parasitoid of H. armigera in southern Africa. The study was undertaken to determine the potential of T. lutea as a biological control agent for augmentative releases as an alternative to chemical control, and to pave the way for the development of a mass-rearing method. The biology of T. lutea was examined in the laboratory on H. armigera, Chilo partellus (Swinhoe), and Cadra (formerly Ephestia) cautella (Walker) (Lepidoptera: Pyralidae). The objectives of the study were to determine (i) the exposure time of UV-irradiation required for killing the embryos of the hosts and the effect of UV-irradiated eggs on life history parameters of T. lutea, (ii) which host(s) and temperature(s) (18, 21, 24, 27, 30 and 35 °C) are suitable for mass-rearing of T. lutea, and (iii) the longevity and age-related reproductive biology of T. lutea on H. armigera. Findings of this study showed that 13 minutes of UV-irradiation were sufficient to kill embryos of all three host species. Life history parameters were not influenced by UV-irradiation but by host species. Parasitism, number of progeny per parasitized egg, proportion of females, and developmental time of T. lutea aried on different host species at temperatures ranging from 18 to 30 °C. Trichogrammatoidea lutea did not develop at 35 °C. Overall parasitism by T. lutea was higher on H. armigera and Cadra cautella compared to Chilo partellus. The number of progeny per parasitized egg was highest on H. armigera compared to Cadra cautella and Chilo partellus. The proportion of females was highest on Chilo partellus, intermediate on Cadra cautella, and lowest on H. armigera. For all species and temperatures tested, parasitism and number of progeny per parasitized egg by T. lutea was highest on H. armigera at 27 °C. The lower threshold for development of T. lutea on all hosts was approximately 12 °C. Female T. lutea parasitized eggs of H. armigera soon after eclosion, with the highest parasitism achieved on the day of eclosion. Though T. lutea parasitized eggs for up to 14 days, it may not be economically viable to keep them in cultures for more than three days since progeny became male biased three days after eclosion. The average longevity of female and male T. lutea was 9 and 6 days, respectively. The life table parameters of T. lutea, the net replacement rate (Ro), mean generation time (T), and instantaneous rate of population increase (rm) were 25.5, 9.79, and 0.33, respectively. The timing of inundative releases of T. lutea must be synchronised with the time that eggs of H. armigera are abundant in the field. The results of this study indicate that T. lutea is a good candidate for further testing for augmentative biological control of H. armigera in the field. If successful, T. lutea may provide opportunities for expanding tactics in the management of H. armigera in southern Africa. Copyright / Dissertation (MSc)--University of Pretoria, 2011. / Zoology and Entomology / unrestricted
13

Dispersal and mating behaviour of Queensland fruit fly, Bactrocera tryoni(Froggatt) (Diptera: Tephritidae): Implicationsfor population establishment and control.

Weldon, Christopher William January 2005 (has links)
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.
14

Dispersal and mating behaviour of Queensland fruit fly, Bactrocera tryoni(Froggatt) (Diptera: Tephritidae): Implicationsfor population establishment and control.

Weldon, Christopher William January 2005 (has links)
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.
15

Viabilidade de dietas artificiais e presas para Eriopis connexa (Germar) (Coleoptera: Coccinellidae) / Viability of artificial diets and preys for Eriopis connexa (Germar) (Coleoptera: Coccinellidae)

Silva, Rafael Braga da 12 February 2009 (has links)
Made available in DSpace on 2015-03-26T13:30:24Z (GMT). No. of bitstreams: 1 texto completo.pdf: 312561 bytes, checksum: 2e92c15ccad6dade9bfe3f5f4800f1bc (MD5) Previous issue date: 2009-02-12 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This research was conducted in the Laboratory of Insects Rearing (LACRI), of the Brazilian Company of Agricultural Research (EMBRAPA Maize and Sorghum Research Center) in Sete Lagoas, Minas Gerais State, Brazil. The objective was to study biological aspects of the immature phase of Eriopis connexa (Germar) (Coleoptera: Coccinellidae), with different artificial diets or preys common to the brazilian corn and sorghum agroecosystems, to develop a rearing methodology and to generate information necessary to the introduction of the predator in the crop system. The experimental design was an entirely randomized blocks, with the larvae of predator maintained in an acclimatized room, under 25±1ºC, 70±10% RH and photophase of 12 hours. The artificial diets were based on ground pet food or diets based on water, brewer's yeast and honey, with or without the addition of ferrous sulphate (FeSO4), wheat germ and soybean flour. The preys offered to E. connexa were eggs (one day or six months frozen) of Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae), eggs (fresh) of Diatraea saccharalis (Fabricius) (Lepidoptera: Pyralidae); eggs (fresh, one day or six months frozen) of Spodoptera frugiperda, with or without scales; recently hatched caterpillars of S. frugiperda; nymphs of Rhopalosiphum maidis (Fitch) or Schizaphis graminum (Rondani) (Hemiptera: Aphididae). All food sources were support ad libitum to E. connexa. Artificial diets, separately, did not support the development of E. connexa. Recently hatched caterpillars of S. frugiperda or eggs of A. kuehniella (six months of freezing), separately or complemented with the artificial diets, were inadequate. Eggs of A. kuehniella frozen for one day, fresh eggs of D. saccharalis, fresh eggs of S. frugiperda without or with scales, frozen for one day or six months, nymphs of S. graminum and R. maidis provided adequate development of the immature phases of the predator, evidencing the polyphagous habit of E. connexa. The results obtained also indicated the nutritional requirements of the predator and can be used to explain the success or not of E. connexa in biological control programs. Eriopis connexa adapted to different food sources, and in the field, it would not be restricted to only one source; and in this way, it could modulate its alimentary regime with alternative food, which is important for the biological control and shows its potential to control corn and sorghum pests. / Esta pesquisa foi conduzida no Laboratório de Criação de Insetos (LACRI), da Empresa Brasileira de Pesquisa Agropecuária (EMBRAPA Milho e Sorgo) em Sete Lagoas, Minas Gerais, Brasil. O objetivo foi estudar aspectos biológicos da fase imatura de Eriopis connexa (Germar) (Coleoptera: Coccinellidae), com diferentes dietas artificiais e presas comuns aos agroecossistemas de milho e de sorgo, visando desenvolver uma metodologia de criação e fornecer subsídios para a introdução desse predador nessasculturas. O delineamento experimental foi em blocos inteiramente casualisados, com as larvas desse predador mantidas em sala climatizada a 25±1ºC, 70±10% UR e fotofase de 12 horas. As dietas artificiais foram à base de pet food triturada e dietas contendo água, levedo de cerveja e mel, com presença ou ausência de sulfato ferroso (FeSO4), gérmen de trigo e farelo de soja. As presas oferecidas a E. connexa foram ovos de Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae), congelados por um dia ou por seis meses; ovos frescos de Diatraea saccharalis (Fabricius) (Lepidoptera: Pyralidae); ovos de Spodoptera frugiperda frescos, sem ou com escamas, congelados por um dia ou por seis meses; lagartas recém-eclodidas de S. frugiperda; ninfas de Rhopalosiphum maidis (Fitch) ou Schizaphis graminum (Rondani) (Hemiptera: Aphididae). Todas as presas e dietas artificiais foram oferecidas ad libitum a E. connexa. As dietas artificiais, isoladamente, não proporcionaram o desenvolvimento de E. connexa e lagartas recémeclodidas de S. frugiperda ou ovos de A. kuehniella (seis meses de congelamento), isoladamente ou complementados com as dietas artificiais, foram inadequados. Ovos de A. kuehniella congelados por um dia, ovos frescos de D. saccharalis, ovos de S. frugiperda frescos sem ou com escamas, congelados por um dia ou por seis meses, ninfas de S. graminum e R. maidis proporcionaram desenvolvimento adequado das fases imaturas desse predador, evidenciando o hábito polífago de E. connexa. Estudos como esse fornecem informações básicas sobre presas que suprem os requisitos nutricionais desse predador e explicações para a falha ou sucesso de E. connexa em programas de controle biológico. Eriopis connexa se adaptou a vários alimentos e, no campo, esse predador não seria restrito a um único alimento; e dessa forma, poderia modular seu regime alimentar com alimentos alternativos, o que é importante para o controle biológico e evidencia seu potencial para controlar pragas de milho e de sorgo.
16

Influência da temperatura na performance de populações de Cotesia flavipes de biofábricas do Brasil / Influence of temperature in the performance of Cotesia flavipes populations of Brazilian biofactories

Nascimento, Thamiris Porto Sipriano [UNESP] 11 September 2017 (has links)
Submitted by THAMIRIS PORTO SIPRIANO null (thamirissipriano@hotmail.com) on 2017-09-25T18:52:01Z No. of bitstreams: 1 Dissertação_Thamiris_P_Sipriano_Nascimento.pdf: 4242269 bytes, checksum: f1cea7d70929c1ee1987ac7edb9418a6 (MD5) / Approved for entry into archive by Monique Sasaki (sayumi_sasaki@hotmail.com) on 2017-09-27T20:37:51Z (GMT) No. of bitstreams: 1 nascimento_tps_me_jabo.pdf: 4242269 bytes, checksum: f1cea7d70929c1ee1987ac7edb9418a6 (MD5) / Made available in DSpace on 2017-09-27T20:37:51Z (GMT). No. of bitstreams: 1 nascimento_tps_me_jabo.pdf: 4242269 bytes, checksum: f1cea7d70929c1ee1987ac7edb9418a6 (MD5) Previous issue date: 2017-09-11 / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / O parasitoide Cotesia flavipes (Hymenoptera: Braconidae), quando liberado em cana-de-açúcar, depende de sua capacidade de dispersão e forrageamento para o efetivo controle de Diatraea saccharalis (Lepidoptera: Crambidae). Nesse sentido, o objetivo do trabalho foi analisar a influência da temperatura nos aspectos biológicos dos insetos produzidos em dez biofábricas brasileiras: I) Santa Ernestina-SP, II) Américo Brasiliense-SP, III) Ribeirão Preto-SP, IV) Pradópolis-SP, V) Sertãozinho-SP, VI) Promissão-SP, VII) Bandeirantes-PR, VIII) Quirinópolis-GO, IX) Campo Novo do Parecis-MT e X) Coruripe-AL, bem como analisar a influência das temperaturas 22, 24, 26, 28, 30, 32 e 34 ± 1°C na performance do parasitoide. Para tanto, foram avaliados: atividade de voo, sobrevivência, capacidade de parasitismo, descendentes viáveis e razão sexual dos insetos produzidos. Os parasitoides da Biofábrica IX foram aqueles que apresentaram a maior porcentagem de insetos voadores (43,4%) a 25°C; independente da temperatura, a maioria das populações apresentaram maiores porcentagens de insetos caminhadores. As fêmeas da biofábrica I apresentaram maior sobrevivência média (56 horas). A temperatura influenciou a sobrevivência dos parasitoides, sendo maior a 22°C para todas as populações. Apenas as biofábricas III) Riberirão Preto-SP e VII) Bandeirantes-PR apresentaram menor produção de descendentes. No geral, as temperaturas de 28 e 30°C favoreceram a produção de descendentes de C. flavipes, sendo que a razão sexual não foi influenciada por esse fator abiótico. / The parasitoid Cotesia flavipes (Hymenoptera: Braconidae), when released in sugarcane, depends on its dispersal and foraging capacity for the effective control of Diatraea saccharalis (Lepidoptera: Crambidae). In this sense, the objective of the work was to analyze the influence of temperature in some biological aspects of the insects produced in ten Brazilian biofactories: I) Santa Ernestina-SP, II) Américo Brasiliense-SP, III) Ribeirão Preto-SP, IV) Pradópolis-SP, V) Sertãozinho, VI) Promissão-SP, VII) Bandeirantes-PR, VIII) Quirinópolis-GO, IX) Campo Novo do Parecis-MT and X) Coruripe-AL, as well to analyze the influence of temperatures 22, 24, 26, 28, 30, 32 and 34 ± 1°C in the parasitoid performance. For that, the following biological parameters were evaluated: flight activity, survival, parasitism capacity, viable offspring and sex ratio of insects produced. The parasitoids of biofactory IX were those that presented the highest percentage of flying adults (43.4%) at 25°C. Independent of temperature, most of the populations had higher percentages of walkers insects. The females of biofactory I presented highest survival average (56 hours). The temperature influenced the parasitoids survival, being higher at 22°C for all populations. Only biofactories III) Ribeirão Preto-SP and VII) Bandeirantes-PR showed lower production of offspring. In general, temperatures of 28 and 30°C favored the production of C. flavipes offspring, and the sex ratio was not influenced by temperature. / CNPq: 134531/2015-9
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Desenvolvimento de Podisus nigrispinus (Dallas, 1851) (Hetoroptera: Pentatomidae) em diferentes temperaturas e uso de soluções químicas para permeabilização de ovos / Development of Podisus nigrispinus (Dallas, 1851) (Hetoroptera: Pentatomidae) in different temperatures and use of chemical solutions for eggs permeabilization

Santos, Ítala Tainy Barreto Francisco dos 05 July 2017 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Podisus nigrispinus Dallas (Heteroptera: Pentatomidae) is a stinkbug used in the biological control of several pests, and has therefore been massively reared in laboratories. Thus, with the objective of optimizing the mass rearing of P. nigrispinus by manipulating the temperature, two experiments were carried out: the first, aimed at investigating the effects of different temperatures on the development and on other biological characteristics of the predatory stinkbug; and the second, aimed at evaluating the processes of dechorionation and permeabilization in the viability of P. nigrispinus eggs with different embryonic ages. In the first experiment, four temperatures were used (17, 21, 25, and 29 °C ± 0.2), and the following parameters were evaluated: duration of the egg and nymphs stages; survival; adults longevity; number of eggs per female; pre-oviposition, oviposition and post-oviposition periods; adult weight and size. As result, an inversely proportional relationship was observed between the parameters duration of the egg and nymphs stages and survival at the temperatures studied. Longer adult longevity, pre-oviposition, oviposition and post-oviposition periods were obtained at a temperature of 17 °C. Conversely, the number of eggs, weight and size were adversely affected. Therefore, temperatures of 21 and 25 °C are the most suitable for the development of the predator; however, the extreme temperatures (17 and 29 °C) allowed delaying or accelerating the life cycle of the insect. In the second experiment, embryos of 24, 48, 72 and 96 hours of age were subjected to chemical solutions for dechorionation and permeabilization. Consequently, embryos with 96 hours of age presented greater viabilities, when compared with those with 24, 48 and 72 hours of age. Observations under a light microscope revealed differences in the chorion thickness after treatments with chemical solutions. Thus, the solutions for dechorionation and permeabilization of P. nigrispinus eggs together with embryonic age affect the viability of embryos to be cryopreserved. / Podisus nigrispinus Dallas (Heteroptera: Pentatomidae) é um percevejo predador utilizado no controle biológico de diversas pragas e por isso tem sido criado em grandes quantidades em laboratórios. Assim, com objetivo de otimizar a criação massal de P. nigrispinus manipulando a temperatura, dois experimentos foram realizados, um voltado à investigação dos efeitos de diferentes temperaturas no desenvolvimento e outras características biológicas do percevejo predador; e outro, voltado à avaliação dos processos de decorionização e permeabilização na viabilidade de ovos de P. nigrispinus com diferentes idades embrionárias. No primeiro experimento, quatro temperaturas foram utilizadas (17, 21, 25 e 29°C ± 0,2), e os parâmetros avaliados foram duração da fase de ovo, dos estádios ninfais, sobrevivências, longevidade de adultos, número de ovos por fêmea, período de pré-oviposição, oviposição e pós-oviposição, peso e tamanho de adultos. Como resultado, foi observada uma relação inversamente proporcional entre os parâmetros duração da fase de ovo e dos estádios ninfais com a sobrevivência nas temperaturas estudadas. Maior longevidade de adultos e período de pré-oviposição, oviposição e pós-oviposição foram obtidos na temperatura de 17°C. Todavia, o número de ovos, peso e tamanho de adultos foram afetados adversamente. Portanto, as temperaturas de 21 e 25°C são mais apropriadas para o desenvolvimento do predador. Entretanto, as temperaturas extremas (17 e 29°C) permitiram retardar ou acelerar o ciclo de vida do inseto, mediante necessidade de inimigos naturais em campo. No segundo experimento, embriões de 24, 48. 72 e 96 horas de idade foram submetidos a soluções químicas para decorionização e permeabilização. Consequentemente, embriões com 96 horas de idade apresentaram maiores viabilidades quando comparados aos de 24, 48 e 72 horas. Observações em microscópio de luz revelaram diferenças na espessura do córion após tratamentos com soluções químicas. Assim, as soluções para decorionização e permeabilização de ovos de P. nigrispinus, juntamente com a idade embrionária afetam a viabilidades de embriões a serem criopreservados. / São Cristóvão, SE
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Free living astigmatid mites (Astigmatina): new taxa, rearing and use for mesostigmatid (Mesostigmata) predatory mite production / Ácaros Astigmatina de vida livre (Astigmatina): novos táxons, criação e uso para a produção de ácaros predadores Mesostigmata

Barbosa, Marina Ferraz de Camargo 18 April 2016 (has links)
The cohort Astigmatina is divided in two major groups: Psoroptidia, composed mainly by feather and fur mites, and Non-psoroptidia, a dominant component of the acarofauna in ephemeral habitats. In these environments Astigmatina usually are saprophages or feed on fungi or bacteria. Astigmatina protonymphs undergo a complete reorganization of the body structure leading to the production of heteromorphic deutonymphs, generally specialized for dispersion through phoresy using arthropods and vertebrates as phoronts. Although most Astigmatina occur in natural environments, some species live in anthropic environments, such as food deposits, where some of them became pests; some Astigmatina infest subterraneous plant organs. Despite their economic and ecological importance, studies on the diversity and taxonomy of Astigmatina in Brazil have been rare over the last decades. The general objective of this thesis was to collaborate to the knowledge of the diversity and to evaluate the potential practical uses of these mites in Brazil. For this, new genera and species were described, method for rearing dust mites was studied and the efficiency of Astigmatina as prey for edaphic predators was evaluated. A new species of Thyreophagus (Astigmatina: Acaridae) was described based on specimens collected in Brazil, the association of three other species of this genus with stored food was reviewed and a key to all species of this genus was prepared. The genus Neotropacarus (Astigmatina: Acaridae), commonly found on plant leaves, was reviewed with the redescription of two species and description of new species collected in Brazil and from the Philippines. Two new genera and seven new species of Acaridae associated with the bee family Apidae was described and a key to Acaridae genera in subfamily Horstiinae was prepared. Several species of Astigmatina were evaluated as prey for predatory mites Stratiolaelaps scimitus (Womersley) (Mesostigmata: Laelapidae) and Protogamasellopsis zaheri Abo-Shnaf, Castilho and Moraes (Mesostigmata: Rhodacaridae), which oviposited on all evaluated astigmatids, with Tyrophagus putrescentiae (Schrank) and Aleuroglyphus ovatus (Tropeau) (Acaridae) being the most suitable prey. Seven foods and two development period, 30 and 60 days, after the introduction of 400 females of two important dust mite species, Blomia tropicalis van Bronswijk, de Cock e Oshima and Dermatophagoides pteronyssinus (Trouessart) were evaluate. With the most suitable foods, the population growth were higher than 20.2 and 15.3 for B. tropicalis and D. pteronyssinus, respectively. / A coorte Astigmatina é dividida em dois grandes grupos: Psoroptidia, composto majoritariamente por ácaros de pena e pelos, e Não-Psoroptidia, componente dominante da acarofauna de habitats efêmeros. Nestes ambientes, os Astigmatina geralmente são saprófagos ou se alimentam de fungos e bactérias. Protoninfas de Astigmatina passam por uma completa reorganização da estrutura corporal levando à produção de deutoninfas heteromórficas geralmente especializadas para dispersão por forese utilizando artrópodes e vertebrados como forontes. Apesar de a maioria dos Astigmatina ocorrer em ambientes naturais, algumas espécies passaram a ocupar ambientes antrópicos, como depósitos de alimentos, onde algumas se tornaram pragas; alguns Astigmatina infestam órgãos subterrâneos de plantas. A despeito de sua importância econômica e ecológica, estudos sobre a diversidade e taxonomia dos Astigmatina no Brasil têm sido raros nas últimas décadas. O objetivo geral desta tese foi colaborar para o conhecimento da diversidade e avaliar o potencial de uso prático de espécies Astigmatina no Brasil. Para isso, novos gêneros e espécies foram descritos, métodos para criação de ácaros de poeira foram estudados e a eficiência de Astigmatina como presas para ácaros predadores edáficos foi avaliada. Uma nova espécie de Thyreophagus (Astigmatina: Acaridae) foi descrita com base em espécimes coletados no Brasil, uma revisão sobre três outras espécies deste gênero associadas com alimentos armazenados foi realizada e uma chave para todas as espécies deste gênero foi elaborada. O gênero Neotropacarus (Astigmatina: Acaridae), comumente associado a folhas de plantas, foi revisado, com redescrição de duas espécies e descrição de novas espécies coletadas no Brasil e nas Filipinas. Dois novos gêneros e sete novas espécies de Acaridae associados à família de abelha Apidae foram descritos e uma chave para os gêneros da subfamília Horstiinae foi elaborada. Diversas espécies de Astigmatina foram avaliadas como presas para os ácaros predadores Stratiolaelaps scimitus (Womersley) (Mesostigmata: Laelapidae) e Protogamasellopsis zaheri Abo-Shnaf, Castilho e Moraes (Mesostigmata: Rhodacaridae), que ovipositaram em todas os Astigmatina avaliados, sendo Tyrophagus putrescentiae (Schrank) e Aleuroglyphus ovatus (Tropeau) (Acaridae) as presas mais promissoras. Sete alimentos e dois períodos de desenvolvimento, 30 e 60 dias, após inoculação de 400 fêmeas de duas espécies importantes na poeira residencial, Blomia tropicalis van Bronswijk, de Cock e Oshima e Dermatophagoides pteronyssinus (Trouessart) foram avaliados. Com os alimentos mais adequados, o crescimento populacional nas colônias foram maiores que 20.2 e 15.3 para B. tropicalis e D. pteronyssinus, respectivamente.
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Determinação da dose de radiação gama esterilizante pela avaliação dos parâmetros biológicos de machos de Ceratitis capitata (Diptera: Tephritidae), linhagem tsl - Vienna 8 / Determination of the dose of gamma radiation sterilization for assessment of biological parameters of male Ceratitis capitata (Diptera: Tephritidae), tsl - Vienna 8 strain

Rocha, Aline Cristina Pereira da 23 August 2011 (has links)
A linhagem tsl (temperature sensitive lethal) - Vienna 8 da espécie Ceratitis capitata, por apresentar mutações que facilitam a criação e a liberação de apenas machos estéreis no campo, vem sendo utilizada em programas de controle da mosca-do-mediterrâneo com o uso da técnica do inseto estéril. O objetivo deste trabalho foi determinar a dose de radiação gama que proporciona o maior índice de esterilidade para machos da espécie C. capitata - linhagem tsl Vienna 8, avaliando seus parâmetros biológicos que indicam a qualidade dos machos estéreis a serem liberados. Pupas marrons (machos) da linhagem tsl, provenientes da criação do laboratório de Irradiação de Alimentos e Radioentomologia do CENA/USP, foram submetidas à radiação gama (60Co) 24 horas antes da emergência nas doses de 0, 30, 60, 90 e 120 Gy. A determinação da dose esterilizante foi baseada na fertilidade de fêmeas sexualmente maduras, da linhagem bissexual e não irradiadas, acasaladas com machos dos diferentes tratamentos. A coleta dos ovos foi realizada diariamente por 6 dias, sendo possível contabilizar e estimar a fecundidade, e obter a taxa de eclosão. A determinação da porcentagem de emergência e da capacidade de voo seguiram o protocolo de controle de qualidade do manual da FAO/IAEA/USDA (2003). Para avaliar a longevidade sob estresse nutricional, os insetos ficaram um período de 48h após a emergência na ausência de água e alimento, e após este período, a mortalidade foi registrada. O tamanho dos testículos (esquerdo e direito) foi obtido ao dissecar machos irradiados e não-irradiados no 8o dia de vida, e mensurar os testículos em uma ocular micrométrica, considerando os maiores comprimento e largura de cada amostra. Para determinar o número de espermatozoides foi necessário dissecar os machos e romper seus testículos. Não houve diferença na taxa de emergência, capacidade de voo e longevidade entre machos irradiados e não-irradiados, e nem na fecundidade das fêmeas acasaladas com os machos dos diferentes tratamentos. A dose esterilizante que resultou na menor fertilidade das fêmeas foi de 120 Gy, com 1,5% de eclosão. Considerando os parâmetros de porcentagem de emergência, capacidade de vôo, longevidade sob estresse, e a esterilidade recomendada para a técnica do inseto estéril que consiste em, aproximadamente, 99% dos ovos serem inviáveis, a dose esterilizante a ser utilizada é a de 120 Gy. O tamanho dos testículos e o número de espermatozoides foram afetados pela radiação, havendo diferença entre os tratamentos. Os machos irradiados com 120 Gy apresentaram uma redução de cerca de 25% no tamanho dos testículos, comparando com os do controle (0 Gy). Os testículos dos machos normais continham uma média de 41910 espermatozoides, e esse valor foi decrescendo ao aumentar a dose de radiação, de maneira que machos irradiados com 120 Gy tinham um número médio de 27921 espermatozoides, e isto, possibilita a recomendação do uso de macho transgênico para controle de C. capitata / The Vienna-8, tsl (temperature sensitive lethal) strain of Ceratitis capitata, by presenting mutations that facilitate the mass rearing and release only of sterile males in the field, has been used in medfly SIT (Sterile Insect Technique) programmes. The objective of this study was to determine the radiation dose that provides the highest level of sterility for Vienna-8, tsl males assessing their biological parameters that indicate the quality of sterile males to be released. Brown pupae (males) of the tsl strain were obtained from the mass rearing of the Food Irradiation and Radioentomologia laboratory of CENA/USP, and they were irradiated (with gamma radiation - 60Co) 24 hours before the emergence at rates of 0, 30, 60, 90 and 120 Gy. The determination of the sterilizing dose was based on fertility of sexually mature females of the bisexual strain and not irradiated, mated with males of different treatments. Eggs were collected daily during 6 days, were counted and it was possible to estimate fecundity, and assess the hatching rate. The emergence and flight ability were determined by following the protocol of quality control manual for FAO/IAEA/USDA (2003). To assess the longevity under nutritional stress, the insects were kept a period of 48 h after emergence in the absence of water and food, and after this period, mortality was recorded. The size of the testes (left and right) was obtained by dissecting irradiated and non-irradiated males at the eighth day of life, and measure the testes in an ocular micrometer, considering the maximum length and width of each sample. To determine the sperm number was necessary to dissect the males and break their testicles. No difference was observed in emergence rate, flight ability and longevity of irradiated and non-irradiated males, nor in the fecundity of females mated with males of different treatments. The sterilizing dose that resulted in lower fertility of females was 120 Gy, with 1.5% hatching. Considering the parameters of emergence, flight ability, longevity under stress and sterility recommended for the sterile insect technique which consists of approximately 99%, the sterilizing dose to be used is 120 Gy. The size of the testes and the sperm number were affected by radiation. Males irradiated with 120 Gy presented a reduction about 25% in size of the testes, compared with the control (0 Gy). The testes of normal males contained an average of 41.910 sperm, and this value was decreased by increasing the dose of radiation, so that males irradiated with 120 Gy had a median of 27.921 sperm, and this allowed to recommend the use of GM male to control C. capitata
20

Determinação da dose de radiação gama esterilizante pela avaliação dos parâmetros biológicos de machos de Ceratitis capitata (Diptera: Tephritidae), linhagem tsl - Vienna 8 / Determination of the dose of gamma radiation sterilization for assessment of biological parameters of male Ceratitis capitata (Diptera: Tephritidae), tsl - Vienna 8 strain

Aline Cristina Pereira da Rocha 23 August 2011 (has links)
A linhagem tsl (temperature sensitive lethal) - Vienna 8 da espécie Ceratitis capitata, por apresentar mutações que facilitam a criação e a liberação de apenas machos estéreis no campo, vem sendo utilizada em programas de controle da mosca-do-mediterrâneo com o uso da técnica do inseto estéril. O objetivo deste trabalho foi determinar a dose de radiação gama que proporciona o maior índice de esterilidade para machos da espécie C. capitata - linhagem tsl Vienna 8, avaliando seus parâmetros biológicos que indicam a qualidade dos machos estéreis a serem liberados. Pupas marrons (machos) da linhagem tsl, provenientes da criação do laboratório de Irradiação de Alimentos e Radioentomologia do CENA/USP, foram submetidas à radiação gama (60Co) 24 horas antes da emergência nas doses de 0, 30, 60, 90 e 120 Gy. A determinação da dose esterilizante foi baseada na fertilidade de fêmeas sexualmente maduras, da linhagem bissexual e não irradiadas, acasaladas com machos dos diferentes tratamentos. A coleta dos ovos foi realizada diariamente por 6 dias, sendo possível contabilizar e estimar a fecundidade, e obter a taxa de eclosão. A determinação da porcentagem de emergência e da capacidade de voo seguiram o protocolo de controle de qualidade do manual da FAO/IAEA/USDA (2003). Para avaliar a longevidade sob estresse nutricional, os insetos ficaram um período de 48h após a emergência na ausência de água e alimento, e após este período, a mortalidade foi registrada. O tamanho dos testículos (esquerdo e direito) foi obtido ao dissecar machos irradiados e não-irradiados no 8o dia de vida, e mensurar os testículos em uma ocular micrométrica, considerando os maiores comprimento e largura de cada amostra. Para determinar o número de espermatozoides foi necessário dissecar os machos e romper seus testículos. Não houve diferença na taxa de emergência, capacidade de voo e longevidade entre machos irradiados e não-irradiados, e nem na fecundidade das fêmeas acasaladas com os machos dos diferentes tratamentos. A dose esterilizante que resultou na menor fertilidade das fêmeas foi de 120 Gy, com 1,5% de eclosão. Considerando os parâmetros de porcentagem de emergência, capacidade de vôo, longevidade sob estresse, e a esterilidade recomendada para a técnica do inseto estéril que consiste em, aproximadamente, 99% dos ovos serem inviáveis, a dose esterilizante a ser utilizada é a de 120 Gy. O tamanho dos testículos e o número de espermatozoides foram afetados pela radiação, havendo diferença entre os tratamentos. Os machos irradiados com 120 Gy apresentaram uma redução de cerca de 25% no tamanho dos testículos, comparando com os do controle (0 Gy). Os testículos dos machos normais continham uma média de 41910 espermatozoides, e esse valor foi decrescendo ao aumentar a dose de radiação, de maneira que machos irradiados com 120 Gy tinham um número médio de 27921 espermatozoides, e isto, possibilita a recomendação do uso de macho transgênico para controle de C. capitata / The Vienna-8, tsl (temperature sensitive lethal) strain of Ceratitis capitata, by presenting mutations that facilitate the mass rearing and release only of sterile males in the field, has been used in medfly SIT (Sterile Insect Technique) programmes. The objective of this study was to determine the radiation dose that provides the highest level of sterility for Vienna-8, tsl males assessing their biological parameters that indicate the quality of sterile males to be released. Brown pupae (males) of the tsl strain were obtained from the mass rearing of the Food Irradiation and Radioentomologia laboratory of CENA/USP, and they were irradiated (with gamma radiation - 60Co) 24 hours before the emergence at rates of 0, 30, 60, 90 and 120 Gy. The determination of the sterilizing dose was based on fertility of sexually mature females of the bisexual strain and not irradiated, mated with males of different treatments. Eggs were collected daily during 6 days, were counted and it was possible to estimate fecundity, and assess the hatching rate. The emergence and flight ability were determined by following the protocol of quality control manual for FAO/IAEA/USDA (2003). To assess the longevity under nutritional stress, the insects were kept a period of 48 h after emergence in the absence of water and food, and after this period, mortality was recorded. The size of the testes (left and right) was obtained by dissecting irradiated and non-irradiated males at the eighth day of life, and measure the testes in an ocular micrometer, considering the maximum length and width of each sample. To determine the sperm number was necessary to dissect the males and break their testicles. No difference was observed in emergence rate, flight ability and longevity of irradiated and non-irradiated males, nor in the fecundity of females mated with males of different treatments. The sterilizing dose that resulted in lower fertility of females was 120 Gy, with 1.5% hatching. Considering the parameters of emergence, flight ability, longevity under stress and sterility recommended for the sterile insect technique which consists of approximately 99%, the sterilizing dose to be used is 120 Gy. The size of the testes and the sperm number were affected by radiation. Males irradiated with 120 Gy presented a reduction about 25% in size of the testes, compared with the control (0 Gy). The testes of normal males contained an average of 41.910 sperm, and this value was decreased by increasing the dose of radiation, so that males irradiated with 120 Gy had a median of 27.921 sperm, and this allowed to recommend the use of GM male to control C. capitata

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