• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 64
  • 47
  • 23
  • 5
  • 4
  • 3
  • 2
  • 2
  • 1
  • Tagged with
  • 167
  • 61
  • 59
  • 40
  • 35
  • 30
  • 26
  • 25
  • 22
  • 21
  • 16
  • 15
  • 15
  • 15
  • 15
  • 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.
121

Níveis populacionais de Leucoptera coffeella (Lepidoptera:Lyonetiidae) e Hypothenemus hampei (Coleoptera: Scolytidae) e a ocorrência de seus parasitoides em sistemas de produção de café orgânico e convencional / Population levels of Leucoptera coffeella (Lepidoptera: Lyonetiidae) and Hypothenemus hampei (Coleoptera: Scolytidae) and the occurrence of their parasitoids in production systems of conventional and organic coffee

Pierre, Leonardo Santa Rosa 08 April 2011 (has links)
A produção de café é uma das atividades de maior tradição agrícola no território brasileiro. As principais pragas que ocorrem no cafeeiro são broca-do-café, Hypothenemus hampei e bicho-mineiro-do-cafeeiro, Leucoptera coffeella e os parasitoides possuem importante papel na regulação dessas pragas. O objetivo deste trabalho foi comparar em sistemas de produção convencional e orgânico de café, os níveis populacionais de H. hampei e L. coffeella e a ocorrência de seus parasitoides. Os experimentos foram realizados em área de café orgânico e convencional no município de Dois Córregos/SP e as amostragens foram realizadas mensalmente de fevereiro de 2009 a junho de 2010. Foram amostradas folhas para os níveis de infestação e de predação de minas por vespas; foram coletadas folhas com minas intactas para a observação da emergência de parasitoides. Foram coletados mensalmente 2 L de frutos de café para a obtenção da infestação da broca; também, foi avaliada a ocorrência do fungo Beauveria bassiana e foram coletados mensalmente frutos de café brocados para a obtenção de parasitoides da broca. Os manejos orgânico e convencional não diferiram estatisticamente em relação às médias das porcentagens de infestação de L. coffeella. Houve diferença em relação às médias das porcentagens de predação das minas por vespas, sendo que no manejo convencional a média foi maior do que no manejo orgânico. Foram obtidos no total 708 himenópteros parasitoides e as espécies coletadas foram Proacrias coffeae, Cirrospilus neotropicus, Cirrospilus sp.1, Cirrospilus sp.2, Closterocerus coffeellae, Closterocerus flavicinctus, Closterocerus sp.1, Horismenus cupreus, Orgilus niger, Centistidea striata e Stiropius reticulatus. Não houve diferença na média da porcentagem de parasitismo entre os manejos, 18,5 % no manejo orgânico e 19,47% no manejo convencional. Em relação à broca-do-café, na safra 2008/2009, as amostragens de frutos brocados foi diferente em função do manejo, porém na safra 2009/2010, as porcentagens de infestação não apresentaram diferença significativa entre as áreas. Na safra 2009/2010, a média de frutos brocados infectados pelo fungo B. bassiana foi de 3,5% e 2,1% do total de frutos nos manejos orgânico e convencional respectivamente. Foram obtidos 25 indivíduos do parasitoide Prorops nasuta na área de café orgânico na safra 2008/2009 e nenhum na área convencional. / Coffee production is one of the most Brazilian traditional activities. The main pests of coffee crops are the coffee berry borer, Hypothenemus hampei and the coffee leaf miner Leucoptera coffeella and the parasitoids play an important role in the control of these pests. This research deals with the comparison between production systems of conventional and organic coffee concerning the population levels of L. coffeella and H. hampei as well as the occurrence of their parasitoids. The experiments were set in areas of conventional and organic coffee and plant (leaf and berries) samples were monthly taken from February/2009 to June/2010, in Dois Córregos, State of São Paulo, Brazil. Coffee leaves were sampled for levels of infestation and mine predation by wasps, while leaves with undisturbed mines were samples to observe the emergence of parasitoids. Two liters of coffee berries were monthly collected to determine the infestation of the coffee berry borer. One also observed the occurrence of the fungus Beauveria bassiana bored coffee berries were monthly collected for obtaining the berry borer parasitoids. The values of the means of percentage of L. coffeella infestation did not statically differ between the organic and the conventional coffee management. The means of percentage of predation by wasps were higher in the conventional management than in the organic one. A total of 708 hymenopteran parasitoids were obtained. The species collected were as follows: Proacrias coffeae, Cirrospilus neotropicus, Cirrospilus sp.1, Cirrospilus sp.2, Closterocerus coffeellae, Closterocerus flavicinctus, Closterocerus sp.1, Horismenus cupreus, Orgilus niger, Centistidea striata and Stiropius reticulatus. The mean percentage of parasitism showed no difference between the organic management (18.5%) and the conventional one (19.47%). As to the coffee berry borer, in the 2008/2009 harvest, the sampling of bored berries was different according to the management. However, in the 2009/2010 harvest, the percentages of infestation did not present significant difference between the areas. At the 2009/2010 harvesting the mean of bored berries infected by the fungus Beauveria bassiana was 3,5% (organic area) and 2.1% (conventional area). A total of 25 specimens of the parasitoid Prorops nasuta were collected in the organic coffee area but none in the conventional coffee area.
122

Habitat manipulation to enhance biological control of light brown apple moth (Epiphyas Postvittana)

Begum, Mahmuda January 2004 (has links)
Trichogramma carverae Oatman and Pinto is mass-released for biological control of the leafroller pest, light brown apple moth, Epiphyas postvittana (Walker) in Australian vineyards. Parasitoid performance can, however, be constrained by a lack of suitable adult food and no information is available on the effect of nectar on the parasitism and longevity of T. carverae. To address this, the effect of alyssum, Lobularia maritima (L.) flowers on E. postvittana parasitism was studied in a vineyard experiment with and without releases of T. carverae. Egg parasitoid activity was assessed with E. postvittana egg �sentinel cards� and no parasitism was recorded in plots without T. carverae releases. Where T. carverae were released, there was no significant enhancement of parasitism by the presence of L. maritima flowers. Three hypotheses were subsequently tested to account for the lack of an effect: (i) T. carverae does not benefit from L. maritima nectar, (ii) T. carverae was feeding on nectar from other flowering plants (weeds) present in the vineyard, (iii) T. carverae was feeding on sugars from ripe grapes. A growth-cabinet experiment using potted L. maritima plants with and without flowers did not support hypothesis one. No parasitism was recorded after day two for T. carverae caged without flowers whilst parasitism occured until day eight in the presence of flowers. A laboratory experiment with common vineyard weeds (Trifolium repens, Hypochoeris radicata, Echium plantagineum) as well as L. maritima did not support hypothesis one but gave partial support to hypothesis two. Survival of T. carverae was enhanced to a small but statistically significant extent in vials with intact flowers of L. maritima, white clover (T. repens) and catsear (H. radicata) but not in vials with flowering shoots of these species from which flowers and flowering buds had been removed. Paterson�s curse (E. plantagineum) flowers had no effect on T. carverae survival. In a laboratory study, punctured grapes significantly enhanced T. carverae survival compared with a treatment without grapes, supporting hypothesis three. Trichogramma carverae performance in the field experiment was probably also constrained by relatively cool and wet weather. Further work on the enhancement of T. carverae efficacy by L. maritima and other carbohydrate sources is warranted. Greenhouse and field experiments were conducted to investigate whether T. carverae benefit from different groundcover plant species. Ten T. carverae adults (<24h after eclosion) were caged with different groundcover species and a control with no plant materials. Epiphyas postvittana egg sentinel cards were used to measure parasitism and longevity was recorded visually. Survival and realised parasitism of T. carverae was significantly higher in L. maritima than in Brassica juncea, Coriandrum sativum, shoots of these species from which flowers had been removed and nil control treatments. A similar experiment with Fagopyrum esculentum (with- and without-flowers) and a control treatment showed that survival was significantly higher in intact F. esculentum than in without-flower and control treatments. There was no significant treatment effect on parasitism in the early stages of that experiment, though parasitism was recorded in the presence of F. esculentum flowers for 12 days, compared with 6 days in other treatments. Higher parasitism was observed in intact Borago officinalis than in the flowerless shoot, water only and no plant material control treatments in a third experiment. There was no significant treatment effect on parasitism. Fitted exponential curves for survival data differed significantly in curvature in the first, second and third experiments but the slope was a non-significant parameter in the second and third experiments. In a second series of laboratory experiments, one male and one female T. carverae were caged with groundcover species to investigate male and female longevity and daily fecundity. Both male and female longevity in F. esculentum and L. maritima treatments were significantly higher than on shoots of these species from which flowers had been removed, and than in the control treatments. Daily fecundity was significantly greater in the intact L. maritima treatment than in all other treatments. Fitted exponential curves for daily fecundity differed significantly in position and slope but not in curvature. There was no significant treatment effect on longevity or parasitism when a male and female were caged with intact B. juncea, B. officinalis or without-flower of these species, nor in the treatment with no plant materials. No parasitism was observed in a survey of naturally occurring egg parasitoids on two sites close to Orange and Canowindra in New South Wales, illustrating the importance of mass releases of T. carverae in biological control of E. postvittana. In an experiment on the Canowindra site, parasitism was significantly higher on day one and day two after T. carverae release when with-flower treatments were compared with without-flower treatments. Parasitism was significantly higher in the F. esculentum treatment than in C. sativum, L. maritima, vegetation without-flowers and control treatments on these dates. On day five, parasitism was higher in C. sativum than in all other treatments. There was no significant increase in parasitism in a second experiment conducted on the Orange site. Coriandrum sativum, F. esculentum and L. maritima appear to be suitable adult food sources for T. carverae and offer some scope for habitat manipulation in vineyards The adults of many parasitoid species require nectar for optimal fitness but very little is known about flower recognition. Flight cage experiments showed that the adults of T. carverae benefited from L. maritima bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on non-white flowers were no greater than when the parasitoids were caged on L. maritima shoots from which flowers had been removed. The possibility that differences between L. maritima cultivars were due to factors other than flower colour, such as nectar quality, was excluded by dyeing white L. maritima flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed L. maritima flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower colour appears, therefore, to be a critical factor in the choice of plants used to enhance biological control, and is likely to also be a factor in the role parasitoids play in structuring invertebrate communities. Provision of nectar producing plants to increase the effectiveness of biological control is one aspect of habitat manipulation, but care needs to be taken to avoid the use of plant species that may benefit pest species. Greenhouse experiments were conducted to investigate whether the adult E. postvittana and larvae benefit from nectar producing groundcover species. Newly emerged E. postvittana adults were caged with different groundcover species and a honey-based artificial adult diet. The longevity of male and female E. postvittana when caged with shoots of borage (B. officinalis) and buckwheat (F. esculentum) bearing flowers was as long as when fed a honey-based artificial diet. This effect was not evident when caged with shoots of these plants from which flowers had been removed. Longevity was significantly lower than in the artificial diet treatment when caged with coriander (C. sativum) or alyssum (L. maritima) irrespective of whether flowers were present or not. There was no significant treatment effect on the lifetime fecundity of E. postvittana. A second experiment with mustard (B. juncea) (with- and without-flowers), water only and honey-based artificial adult diet showed no significant treatment effects on the longevity of male and female E. postvittana or on the lifetime fecundity of E. postvittana. The anomalous lack of a difference between the water and honey-based diet treatments precludes making conclusions on the value of B. juncea for E. postvittana. Two greenhouse experiments were conducted to evaluate the effects of groundcover species on the larval development of E. postvittana. In the first experiment, larval mortality was significantly higher in C. sativum, and L. maritima than in B. juncea, B. officinalis and white clover (T. repens) a known host of E. postvittana. Coriandrum sativum and L. maritima extended the larval period. In B. juncea and B. officinalis, mortality did not differ from that in T. repens. In F. esculentum, larval mortality was significantly higher than in T. repens. A short larval period was observed on B. juncea, B. officinalis and F. esculentum. Fitted exponential curves for larval mortality differed significantly in curvature between plant treatments. Similarly, successful pupation was significantly lower in C. sativum, F. esculentum and L. maritima than in T. repens. The percentage of successful pupation in B. juncea and B. officinalis did not differ from F. esculentum and T. repens. Fitted exponential curves for pupation differed significantly in curvature. A similar trend was observed in a second experiment with potted plants. The overall results suggest that C. sativum and L. maritima denied benefit to E. postvittana adults and larvae, so could be planted as vineyard groundcover with minimal risk of exacerbating this pest. Overall results suggest that T. carverae require nutrients to reach their full reproductive potential and flowers provide such nutrients. Lobularia maritima and C. sativum may be considered �selective food plants� for T. carverae whereas F. esculentum appears to be a �non-selective food plant�; both T. carverae and E. postvittana benefited from it. Fruits such as grapes can be used as food resources in habitat manipulation and this merits further research. This result also suggests that within species flower colour is an important factor for flower selection in habitat manipulation.
123

Habitat manipulation to enhance biological control of light brown apple moth (Epiphyas Postvittana)

Begum, Mahmuda January 2004 (has links)
Trichogramma carverae Oatman and Pinto is mass-released for biological control of the leafroller pest, light brown apple moth, Epiphyas postvittana (Walker) in Australian vineyards. Parasitoid performance can, however, be constrained by a lack of suitable adult food and no information is available on the effect of nectar on the parasitism and longevity of T. carverae. To address this, the effect of alyssum, Lobularia maritima (L.) flowers on E. postvittana parasitism was studied in a vineyard experiment with and without releases of T. carverae. Egg parasitoid activity was assessed with E. postvittana egg �sentinel cards� and no parasitism was recorded in plots without T. carverae releases. Where T. carverae were released, there was no significant enhancement of parasitism by the presence of L. maritima flowers. Three hypotheses were subsequently tested to account for the lack of an effect: (i) T. carverae does not benefit from L. maritima nectar, (ii) T. carverae was feeding on nectar from other flowering plants (weeds) present in the vineyard, (iii) T. carverae was feeding on sugars from ripe grapes. A growth-cabinet experiment using potted L. maritima plants with and without flowers did not support hypothesis one. No parasitism was recorded after day two for T. carverae caged without flowers whilst parasitism occured until day eight in the presence of flowers. A laboratory experiment with common vineyard weeds (Trifolium repens, Hypochoeris radicata, Echium plantagineum) as well as L. maritima did not support hypothesis one but gave partial support to hypothesis two. Survival of T. carverae was enhanced to a small but statistically significant extent in vials with intact flowers of L. maritima, white clover (T. repens) and catsear (H. radicata) but not in vials with flowering shoots of these species from which flowers and flowering buds had been removed. Paterson�s curse (E. plantagineum) flowers had no effect on T. carverae survival. In a laboratory study, punctured grapes significantly enhanced T. carverae survival compared with a treatment without grapes, supporting hypothesis three. Trichogramma carverae performance in the field experiment was probably also constrained by relatively cool and wet weather. Further work on the enhancement of T. carverae efficacy by L. maritima and other carbohydrate sources is warranted. Greenhouse and field experiments were conducted to investigate whether T. carverae benefit from different groundcover plant species. Ten T. carverae adults (<24h after eclosion) were caged with different groundcover species and a control with no plant materials. Epiphyas postvittana egg sentinel cards were used to measure parasitism and longevity was recorded visually. Survival and realised parasitism of T. carverae was significantly higher in L. maritima than in Brassica juncea, Coriandrum sativum, shoots of these species from which flowers had been removed and nil control treatments. A similar experiment with Fagopyrum esculentum (with- and without-flowers) and a control treatment showed that survival was significantly higher in intact F. esculentum than in without-flower and control treatments. There was no significant treatment effect on parasitism in the early stages of that experiment, though parasitism was recorded in the presence of F. esculentum flowers for 12 days, compared with 6 days in other treatments. Higher parasitism was observed in intact Borago officinalis than in the flowerless shoot, water only and no plant material control treatments in a third experiment. There was no significant treatment effect on parasitism. Fitted exponential curves for survival data differed significantly in curvature in the first, second and third experiments but the slope was a non-significant parameter in the second and third experiments. In a second series of laboratory experiments, one male and one female T. carverae were caged with groundcover species to investigate male and female longevity and daily fecundity. Both male and female longevity in F. esculentum and L. maritima treatments were significantly higher than on shoots of these species from which flowers had been removed, and than in the control treatments. Daily fecundity was significantly greater in the intact L. maritima treatment than in all other treatments. Fitted exponential curves for daily fecundity differed significantly in position and slope but not in curvature. There was no significant treatment effect on longevity or parasitism when a male and female were caged with intact B. juncea, B. officinalis or without-flower of these species, nor in the treatment with no plant materials. No parasitism was observed in a survey of naturally occurring egg parasitoids on two sites close to Orange and Canowindra in New South Wales, illustrating the importance of mass releases of T. carverae in biological control of E. postvittana. In an experiment on the Canowindra site, parasitism was significantly higher on day one and day two after T. carverae release when with-flower treatments were compared with without-flower treatments. Parasitism was significantly higher in the F. esculentum treatment than in C. sativum, L. maritima, vegetation without-flowers and control treatments on these dates. On day five, parasitism was higher in C. sativum than in all other treatments. There was no significant increase in parasitism in a second experiment conducted on the Orange site. Coriandrum sativum, F. esculentum and L. maritima appear to be suitable adult food sources for T. carverae and offer some scope for habitat manipulation in vineyards The adults of many parasitoid species require nectar for optimal fitness but very little is known about flower recognition. Flight cage experiments showed that the adults of T. carverae benefited from L. maritima bearing white flowers to a greater extent than was the case for light pink, dark pink or purple flowered cultivars, despite all cultivars producing nectar. Survival and realised parasitism on non-white flowers were no greater than when the parasitoids were caged on L. maritima shoots from which flowers had been removed. The possibility that differences between L. maritima cultivars were due to factors other than flower colour, such as nectar quality, was excluded by dyeing white L. maritima flowers by placing the roots of the plants in 5% food dye (blue or pink) solution. Survival of T. carverae was lower on dyed L. maritima flowers than on undyed white flowers. Mixing the same dyes with honey in a third experiment conducted in the dark showed that the low level of feeding on dyed flowers was unlikely to be the result of olfactory or gustatory cues. Flower colour appears, therefore, to be a critical factor in the choice of plants used to enhance biological control, and is likely to also be a factor in the role parasitoids play in structuring invertebrate communities. Provision of nectar producing plants to increase the effectiveness of biological control is one aspect of habitat manipulation, but care needs to be taken to avoid the use of plant species that may benefit pest species. Greenhouse experiments were conducted to investigate whether the adult E. postvittana and larvae benefit from nectar producing groundcover species. Newly emerged E. postvittana adults were caged with different groundcover species and a honey-based artificial adult diet. The longevity of male and female E. postvittana when caged with shoots of borage (B. officinalis) and buckwheat (F. esculentum) bearing flowers was as long as when fed a honey-based artificial diet. This effect was not evident when caged with shoots of these plants from which flowers had been removed. Longevity was significantly lower than in the artificial diet treatment when caged with coriander (C. sativum) or alyssum (L. maritima) irrespective of whether flowers were present or not. There was no significant treatment effect on the lifetime fecundity of E. postvittana. A second experiment with mustard (B. juncea) (with- and without-flowers), water only and honey-based artificial adult diet showed no significant treatment effects on the longevity of male and female E. postvittana or on the lifetime fecundity of E. postvittana. The anomalous lack of a difference between the water and honey-based diet treatments precludes making conclusions on the value of B. juncea for E. postvittana. Two greenhouse experiments were conducted to evaluate the effects of groundcover species on the larval development of E. postvittana. In the first experiment, larval mortality was significantly higher in C. sativum, and L. maritima than in B. juncea, B. officinalis and white clover (T. repens) a known host of E. postvittana. Coriandrum sativum and L. maritima extended the larval period. In B. juncea and B. officinalis, mortality did not differ from that in T. repens. In F. esculentum, larval mortality was significantly higher than in T. repens. A short larval period was observed on B. juncea, B. officinalis and F. esculentum. Fitted exponential curves for larval mortality differed significantly in curvature between plant treatments. Similarly, successful pupation was significantly lower in C. sativum, F. esculentum and L. maritima than in T. repens. The percentage of successful pupation in B. juncea and B. officinalis did not differ from F. esculentum and T. repens. Fitted exponential curves for pupation differed significantly in curvature. A similar trend was observed in a second experiment with potted plants. The overall results suggest that C. sativum and L. maritima denied benefit to E. postvittana adults and larvae, so could be planted as vineyard groundcover with minimal risk of exacerbating this pest. Overall results suggest that T. carverae require nutrients to reach their full reproductive potential and flowers provide such nutrients. Lobularia maritima and C. sativum may be considered �selective food plants� for T. carverae whereas F. esculentum appears to be a �non-selective food plant�; both T. carverae and E. postvittana benefited from it. Fruits such as grapes can be used as food resources in habitat manipulation and this merits further research. This result also suggests that within species flower colour is an important factor for flower selection in habitat manipulation.
124

Comportamento de parasitismo de Acarophenax lacunatus e impacto de sua forésia em Rhyzopertha dominica / Parasitism behavior by Acarophenax lacunatus and impact of its phoresy on Rhyzopertha dominica

Rocha, Silma Leite 28 February 2007 (has links)
Made available in DSpace on 2015-03-26T13:30:16Z (GMT). No. of bitstreams: 1 texto completo.pdf: 183371 bytes, checksum: d1e3f53fdf8243e46cb5663bc7707bdf (MD5) Previous issue date: 2007-02-28 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Acarophenax lacunatus (Cross & Krantz) (Prostigmata: Acarophenacidae) is a parasitoid mite on eggs of some Insecta; this could be a complementary tool for pest management in stored products. This mite has preference for eggs of Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae) attaching to the adult beetles for dispersion, a phenomenon referred to as phoresy. Behavioral studies are critical for the understanding of several aspects of arthropod biology. No investigation on the parasitism behavior of A. lacunatus on and its phoretic relationship with R. dominica has been conducted yet and thus it was the objective of this work. Two sets of studies were conducted: the first investigated the parasitism behavior of A. lacunatus on the egg of R. dominica, and the second investigated whether phoresy of A. lacunatus would affect flight initiation and if phoretic loads would affected the walking behavior of adult beetles. In the study of parasitism behavior of A. lacunatus, the mite was placed in an arena together with in one host egg and observed until the parasitism. Based on observations of several individuals, the parasitism behavior was described with the following behavioral categories: initial exploratory march, exploratory march after finding the host egg and parasitism. In the test of flight initiation, adults of R. dominica with and without phoretic mites were placed in a bioassay chamber, which was evaluated in 10-min intervals for one hour to verify whether or not there were mites attached to the beetles that initiated flight. Results showed that most beetles initiating flight had no mites attached to their bodies. In the second test involving phoresy, beetles with different phoretic loads (0, 2, 4, 6, 8, 11 and 23 mites/insect) were observed in a video-recorded arena so as to determine the distance walked, time spent walking and time without walking. Beetles with phoretic loads of two, four and six mites walked longer distances and stayed less time without walking unlike beetles with phoretic loads of 11 and 23 mites, which tended to show a walking pattern similar to beetles without phoretic mites. In addition to observing a uniform pattern in the parasitism behavior by A. lacunatus on eggs of R. dominica, the presence of phoretic mites was associated with low frequency of flight initiation by the beetle, and depending on the number of mites attached to coleopteran, walking was stimulated or unaffected. / Acarophenax lacunatus (Cross & Krantz) (Prostigmata: Acarophenacidae) é um ácaro parasitóide de ovos de algumas famílias da classe Insecta, podendo ser uma ferramenta complementar no controle de pragas de produtos armazenados. Este ácaro tem preferência por parasitar ovos de Rhyzopertha dominica (Fabricius) (Coleoptera: Bostrichidae), em cujos adultos realiza forésia, forma passiva de deslocamento. Estudos a respeito do comportamento são de fundamental importância para a compreensão de diversos aspectos da biologia de artrópodes; no entanto estudos mais detalhados a respeito do comportamento de parasitismo de A. lacunatus e de sua relação forética com R. dominica ainda são poucos. Desta forma estudou-se o comportamento de parasitismo de A. lacunatus em ovos de R. dominica, bem como sua relação forética com esse coleóptero. Para a realização deste trabalho foram feitos dois ensaios. O primeiro abordou o estudo do comportamento de parasitismo de A. lacunatus em ovos de R. dominica. O segundo ensaio foi realizado em dois testes: um para verificar se a forésia de A. lacunatus afetaria a iniciação de vôo de seu hospedeiro e o outro para averiguar se a carga forética prejudicaria o caminhamento do seu hospedeiro. No estudo do comportamento de parasitismo de A. lacunatus, o ácaro foi colocado em uma arena, juntamente com um ovo hospedeiro, sendo observado até o parasitismo. A partir destas observações, descreveu-se o comportamento de parasitismo com as seguintes categorias comportamentais: marcha exploratória inicial, marcha exploratória após o encontro do ovo e parasitismo propriamente dito. Para o teste da relação entre forésia e iniciação de vôo utilizou-se adultos não-sexados de R. dominica, com e sem ácaros foréticos. Estes coleópteros foram colocados em uma câmara de bioensaio que foi avaliada, em intervalos de 10 minutos, por uma hora, para verificar se os besouros que iniciaram vôo tinham ou não ácaros foréticos. Observou-se que a maior parte dos besouros que iniciaram vôo não tinha ácaros aderidos ao corpo. No teste da relação de cargas foréticas com o caminhamento de R. dominica, besouros contendo diferentes cargas foréticas (0, 2, 4, 6, 8, 11 e 23 ácaros/inseto) foram observados quanto à distância caminhada, ao tempo de caminhamento e o tempo sem caminhar. Besouros com cargas foréticas de dois, quatro e seis ácaros caminharam mais e ficaram menos tempo sem caminhar ao contrário do observado para besouros com cargas foréticas de oito, 11 e 23 ácaros, os quais tenderam a ter um padrão de caminhamento semelhante aos de besouros sem ácaros foréticos. Em conclusão, além de se verificar que há um padrão comportamental uniforme no parasitismo de A. lacunatus sobre ovos de R. dominica, verificou-se que a presença de ácaros foréticos esteve associada à baixa freqüência de iniciação de vôo do besouro, e que, dependendo da densidade de ácaros presos ao coleóptero, o caminhamento parece ser estimulado ou não afetado.
125

Variation et évolution de la composition du venin des guêpes parasitoïdes Psyttalia (Hymenoptera, Braconidae) et Leptopilina (Hymenoptera, Figitidae) : une cause possible d'échec et de succès en lutte biologique ? / Variation and evolution of venom contents in the parasitoid wasps Psyttalia (Hymenoptera, Braconidae) and Leptopilina (Hymenoptera, Figitidae) : a cause of success and failure in biological control ?

Mathé-Hubert, Hugo 23 October 2014 (has links)
Les guêpes endoparasitoïdes effectuent leur développement dans un hôte arthropode, entraînant sa mort. Parmi les stratégies assurant leur succès parasitaire, la plus commune est l’injection de venin dans l’hôte lors de l’oviposition, provoquant la suppression de l’immunité de l’hôte. Il est connu que la composition du venin est variable entre espèces et que la virulence des parasitoïdes peut évoluer rapidement. Pourtant la variation intraspécifique de la composition du venin n’a jamais été étudiée alors qu’elle est essentielle pour comprendre l’évolution de la gamme d’hôte des parasitoïdes, un paramètre clé en lutte biologique. Cette thèse a permis de démontrer l’existence d’une variabilité inter-Individuelle du venin, et de développer une méthode basée sur l’analyse de profiles d’électrophorèse 1D à l’aide de fonctions “R” permettant la comparaison statistique de la composition protéique d’un grand nombre d’individus. Des évolutions expérimentales ont ensuite été réalisée sur Psyttalia lounsburyi et Leptopilina boulardi pour étudier les effets de la variabilité du venin lors d’un changement d’environnement brutal. Globalement, cette thèse a mis en évidence que la composition du venin (i) est très variable à tous les niveaux étudiés, (ii) évolue rapidement et (iii) impacte des paramètres clés de la biologie des parasitoïdes. Ceci pourrait avoir d’importantes implications en lutte biologique et pose la question des mécanismes de maintien de la variabilité du venin dans le milieu naturel. / Endoparasitoid wasps lay eggs and develop inside arthropod hosts, leading to their death. They have evolved various strategies to ensure parasitism success, notably the injection with the eggs of venom that suppresses the host immunity. Although venom composition has been characterized in a growing number of parasitoid families and recent studies suggest that parasitoid virulence can rapidly evolve, the intraspecific variation of venom and its short-Term evolvability remained to be investigated. This information is however essential for understanding the evolution of parasitoid host range and may have implications in biological control. This thesis allowed to demonstrate the occurrence of inter-Individual variability of venom and to develop a method based on the analysis of electrophoretic 1D profiles and the use of “R” functions allowing statistic comparison of protein quantities from numerous individuals. Then, to study the effect of this variability of the venom composition, experimental evolution studies were performed on Psyttalia lounsburyi and Leptopilina boulardi. Overall, the thesis evidenced that parasitoid venom composition (i) is variable at all studied biological levels (ii) changes rapidly, confirming its high evolvability, and (iii) influences key parameters of the parasitoid biology. This may have important implications in biocontrol and raises the question of the mechanisms sustaining this variability.
126

Distribuição espacial do parasitismo de Cotesia flavipes (Cameron, 1891) (ymenoptera: Braconidae) em cana-de-açúcar

Volpe, Haroldo Xavier Linhares [UNESP] 31 July 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:25:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-31Bitstream added on 2014-06-13T20:32:40Z : No. of bitstreams: 1 volpe_hxl_me_jabo.pdf: 702821 bytes, checksum: 43e3858ad875276bff4de70b0a19e5db (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / distribuição espacial do parasitismo, número de machos, fêmeas e total de adultos emergidos da geração F2 do parasitóide larval de Diatraea saccharalis (Fabricius), Cotesia flavipes (Cameron), foi estudada em um talhão comercial de 100x105 m de cana-de-açúcar da variedade CTC 3, com 7 meses, dividido em 100 parcelas de 105 m2, usando a metodologia de liberação de 4 pontos por hectare, com 1500 parasitóides espaçados 50 m entre eles. Em cada parcela foram colocados 10 colmos de cana com uma larva de D. saccharalis em seu interior fixados no solo para avaliação do parasitismo e número de insetos emergidos. Os índices de dispersão utilizados foram: razão variância/média (I), índice de Morisita (Iδ), coeficiente de Green (Cx) e expoente k da distribuição binomial negativa. A distribuição binomial negativa foi o modelo mais adequado para representar a distribuição de freqüência do parasitóide, já que a variância foi superior à média para todas as variáveis avaliadas. A análise dos índices de agregação mostrou que esse inseto se distribui de maneira agregada no campo. O uso da Geoestatística permitiu quantificar e mapear a distribuição de C. flavipes, mostrando ser uma ferramenta útil para teste de metodologias de liberação desse parasitóide. / The spatial distribution of the parasitism, number of males, females and total of adults emerged of the F2 generation of the Diatraea saccharalis (Fabricius), larval parasitoid of Cotesia flavipes (Cameron), was studied in a commercial stand of extension of 100x105 m of sugarcane variety CTC 3, with 7 months old, divided into 100 plots with 105 square meters using the liberation methodology of 4 points per hectare, with 1,500 parasitoids spaced 50 m between them. The plot contained 10 stems with one D. saccharalis larvae inside fixed in the soil were used to evaluate the parasitism and the number of insects emerged. The dispersion indexes used were: variance/mean ratio (I), Morisita’s index (Iδ), Green’s coefficient (Cx) and k exponent of negative binomial distribution. The negative binomial distribution was more representative to the frequency distribution data of the parasitoid, since the variance was superior to the average. The analysis by the aggregation index showed that the most of the samplings presented aggregate distribution in the crop. The geoestatistics could be an useful tool to be applied to tests of different inundative liberations to this parasitoid.
127

Parasitismo de ovos de Leptopharsa heveae Drake & Poor, 1935 (Hemiptera: Tingidae) em seringueira (Hevea brasiliensis Müell. Arg.) no Estado do Mato Grosso

Santos, Rodrigo Souza [UNESP] 02 October 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:05Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-10-02Bitstream added on 2014-06-13T19:42:24Z : No. of bitstreams: 1 santos_rs_dr_jabo.pdf: 1593965 bytes, checksum: fdd7c0ec03d968f08907273deefc9096 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Plantacoes E. Michelin Ltda. / O objetivo deste trabalho foi realizar um levantamento de parasitóides associados à Leptopharsa heveae (Hemiptera: Tingidae) em talhões de seringueiras de cultivo na fazenda da empresa “Plantações E. Michelin Ltda.”, município de Itiquira – MT (17º22’23’’S, 54º44’23’’W). Foram realizados três ensaios para determinar a ocorrência, porcentagem de parasitismo e flutuação populacional da praga e parasitóides em talhões com e sem aplicação de produtos fitossanitários. Também foi verificada a influência a idade da folha de seringueira na oviposição de L. heveae e na ocorrência de parasitóides e a distribuição espacial de parasitóides nos lados dos talhões, em cinco clones de seringueira (RRIM 600, PR 255, PB 217, PB 235 e GT 1). Nos ensaios realizados eram coletadas folhas maduras (completamente expandidas), sendo demarcadas as áreas contendo os ovos de L. heveae, do terço inferior da copa de árvores dos cinco clones estudados. No ensaio correspondente à influência da idade das folhas, além de folhas maduras, eram coletadas folhas intermediárias (semiexpandidas e verde-claras) e novas (não expandidas e arroxeadas). Em todos os ensaios realizados a espécie Erythmelus tingitiphagus (Hymenoptera: Mymaridae) foi a mais abundante e freqüente. A porcentagem de parasitismo de E. tingitiphagus sobre ovos de L. heveae variou entre 13,8% no clone PB 235 a 30,8% no RRIM 600 em condições naturais. Os picos populacionais de L. heveae e de E. tingitiphagus deram-se nos meses de outubro e novembro nas áreas estudadas. Verificou-se que a distribuição de E. tingitiphagus ocorreu de maneira eqüitativa nos lados dos talhões, com tendência a concentrar-se no centro dos mesmos. A oviposição de L. heveae é maior em folhas maduras em relação às intermediárias e novas. / The objective of this work was to make a survey of parasitoids associated with Leptopharsa heveae (Hemiptera: Tingidae) in lots of rubber trees cultivation on the farm of the company “Plantações E. Michelin Ltda.”, municipality of Itiquira – MT (17º22’23’’, 54º44’23’’W). Three experiments were made to determine the occurrence, percentage of parasitism and population flotation of the pest and parasitoids in lots with and without application of pesticides. Also the influence of the age of the rubber tree leaf was verified in the oviposition of L. heveae and in the parasitoids occurrence and the space distribution of parasitoids beside the lots, in five rubber tree clones (RRIM 600, PR 255, PB 217, PB 235 and GT 1). Through the experiments made, ripe leaves were collected (completely expanded), being demarcated the areas containing L. heveae’s eggs, of the inferior third of the canopies of the five studied clones. In the experiment corresponding to the influence of the age of the leaves, besides ripe leaves, intermediate leaves were collected (semi-expanded and light green) and new (unexpanded and purple). In all experiments made, the species Erythmelus tingitiphagus (Hymenoptera: Mymaridae) was the most abundant and frequent. The percentage of parasitism of E. tingitiphagus on eggs of L. heveae varied between 13.8% in the PB 235 clone, to 30.8% in RRIM 600 in natural conditions. L. heveae’s and E. tingitiphagus’s population picks happened in the months of October and November in the studied areas. It was verified that that the distribution of E. tingitiphagus happened in an equal way in the sides of the lots, with tendency to concentrate in the center of themselves. The oviposition of L. heveae is larger in ripe leaves related to the intermediate and new ones.
128

Revisão taxonômica do gênero Notiospathius Matthews & Marsh (Hymenoptera: Braconidae: Doryctinae)

Nunes, Juliano Fiorelini 03 June 2011 (has links)
Made available in DSpace on 2016-06-02T19:29:43Z (GMT). No. of bitstreams: 1 4080.pdf: 25033714 bytes, checksum: 53bfe486e4c53508c5e1093741e915a6 (MD5) Previous issue date: 2011-06-03 / Financiadora de Estudos e Projetos / The taxonomy, despite its recognized importance within biological sciences, has not had the attention it deserves, especially in Brazil and in mega-diverse countries where biodiversity is largely unknown or underestimated. This thesis aims to contribute to the taxonomic knowledge by revising the genus Notiospathius, admittedly speciose in the Neotropics, but not revised yet. The material studied in this work comes from several collections from Brazil and the world and combine a total of 2163 specimens from more than 130 cities in 12 countries. It was made a new and broader diagnosis of the genus. Twenty-six probable new species are described; ten species are registered and their geographic distributions were expanded. The first record of males for six of these species is done. Maps and photos for each species and morphospecies are presented. It was performed an identification key for all morphospecies and for most Notiospathius species. According to this revision, the genus is confirmed as one of the most important within the Subfamily Doryctinae in the Neotropical region in terms of species richness, besides nearly to double the knowledge of it. / A taxonomia, apesar de sua reconhecida importância entre as ciências biológicas, não tem tido a atenção que merece, especialmente no Brasil e nos países megadiversos, onde grande parte da biodiversidade está subestimada ou desconheida. Esta tese tem o objetivo de contribuir com o conhecimento taxonômico, revisando o gênero Notiospathius, reconhecidamente especioso na região Neotropical. O material deste trabalho é proveniente de diversas coleções do Brasil e do exterior e reuniu um total de 2163 exemplares provenientes cerca de 130 localidades em 12 países. Apresenta-se uma diagnose com novos caracteres que definem o gênero. Vinte e seis novas espécies são descritas. Dez espécies são novos registros com a ampliação do conhecimento da distribuição geográfica. Registro de 6 machos das espécies já descritas é feito. Mapas e fotos para cada uma das espécies são apresentados. Uma chave de identificação para a maioria das espécies de Notiospathius é apresentada. Com esta revisão, confirma-se o gênero como um dos mais importantes dentro da Subfamília Doryctinae na região Neotropical em termos de riqueza de espécies e amplia-se o conhecimento a respeito do grupo.
129

Distribuição espacial do parasitismo de Cotesia flavipes (Cameron, 1891) (ymenoptera: Braconidae) em cana-de-açúcar /

Volpe, Haroldo Xavier Linhares. January 2009 (has links)
Resumo: distribuição espacial do parasitismo, número de machos, fêmeas e total de adultos emergidos da geração F2 do parasitóide larval de Diatraea saccharalis (Fabricius), Cotesia flavipes (Cameron), foi estudada em um talhão comercial de 100x105 m de cana-de-açúcar da variedade CTC 3, com 7 meses, dividido em 100 parcelas de 105 m2, usando a metodologia de liberação de 4 pontos por hectare, com 1500 parasitóides espaçados 50 m entre eles. Em cada parcela foram colocados 10 colmos de cana com uma larva de D. saccharalis em seu interior fixados no solo para avaliação do parasitismo e número de insetos emergidos. Os índices de dispersão utilizados foram: razão variância/média (I), índice de Morisita (Iδ), coeficiente de Green (Cx) e expoente k da distribuição binomial negativa. A distribuição binomial negativa foi o modelo mais adequado para representar a distribuição de freqüência do parasitóide, já que a variância foi superior à média para todas as variáveis avaliadas. A análise dos índices de agregação mostrou que esse inseto se distribui de maneira agregada no campo. O uso da Geoestatística permitiu quantificar e mapear a distribuição de C. flavipes, mostrando ser uma ferramenta útil para teste de metodologias de liberação desse parasitóide. / Abstract: The spatial distribution of the parasitism, number of males, females and total of adults emerged of the F2 generation of the Diatraea saccharalis (Fabricius), larval parasitoid of Cotesia flavipes (Cameron), was studied in a commercial stand of extension of 100x105 m of sugarcane variety CTC 3, with 7 months old, divided into 100 plots with 105 square meters using the liberation methodology of 4 points per hectare, with 1,500 parasitoids spaced 50 m between them. The plot contained 10 stems with one D. saccharalis larvae inside fixed in the soil were used to evaluate the parasitism and the number of insects emerged. The dispersion indexes used were: variance/mean ratio (I), Morisita's index (Iδ), Green's coefficient (Cx) and k exponent of negative binomial distribution. The negative binomial distribution was more representative to the frequency distribution data of the parasitoid, since the variance was superior to the average. The analysis by the aggregation index showed that the most of the samplings presented aggregate distribution in the crop. The geoestatistics could be an useful tool to be applied to tests of different inundative liberations to this parasitoid. / Orientador: José Carlos Barbosa / Coorientador: Sergio Antonio de Bortoli / Banca: Nelson Wanderley Perioto / Banca: Wilson Itamar Maruyama / Mestre
130

Espécies de parasitóides (Hymenoptera: Braconidae) de moscas-das-frutas (Diptera: Tephritidae) no estado de São Paulo: caracterização taxonômica, distribuição geográfica e percentagem de parasitismo / Braconid parasitoids (hymenoptera) of fruit flies (diptera: tephritidae) in the state of são paulo: taxonomic characterization, geographic distribution and percentage of parasitism

Cláudia Fidelis Marinho 22 April 2004 (has links)
A partir de 148 amostras com parasitóides da família Braconidae, provenientes de levantamentos realizados com as moscas-das-frutas no Estado de São Paulo, foi feito estudo taxonômico, de distribuição e de associação com as moscas hospedeiras e fruteiras. Em 33 municípios, foram coletados 3.009 exemplares. A subfamília Opiinae foi a mais abundante com 96,2% dos exemplares. Apenas 3,8% dos parasitóides pertenciam à subfamília Alysiinae. Foram coletadas seis espécies de braconídeos: Doryctobracon areolatus (Szépligeti), Doryctobracon brasiliensis (Szépligeti), Utetes anastrephae (Viereck), Opius bellus (Wesmael) e Opius sp. (Wesmael), além do alisiíneo Asobara anastrephae (Muesebeck). A maior parte dos braconídeos (77,5%) pertencia a D. areolatus. Esta espécie foi associada ao maior número de espécies frutíferas (26), em 7 famílias, e ocorreu na maioria dos municípios amostrados (30). Foi associada a Anastrepha fraterculus (Wied.), A. obliqua (Macquart) e A. amita Zucchi, sendo obtida pela primeira vez de larvas de moscas em frutos de wampi, Clausena lansium (Lour) Skeels, e de canela-batalha, Cryptocarya aschersoniana Mez. Doryctobracon brasiliensis foi associada apenas A. fraterculus, sendo registrado pela primeira vez em ameixa-japonesa, Prunus salicina Lindl. Não foi possível associar as demais espécies de parasitóides às moscas-das-frutas. Opius sp. foi associada às larvas em canela-batalha (primeiro registro de planta associada). A percentagem de parasitismo de tefritídeos nos 33 municípios foi de 7,75%, variando de 0,02% a 40%. Foi elaborada uma chave de identificação para as espécies. / This work presents the results of a survey of braconid fruit fly parasitoids from 33 localities in the State of São Paulo. In addition to the taxonomic studies, data of geographical distribution and association of braconid species to insect hosts and associated plants were also performed. A total of 3,009 specimens were colleted. The subfamily Opiinae was the most abundant with 96.2% of specimens colleted, and only 3.8% of the parasitoids belonged to the subfamily Alysiinae. Six species of braconids were collected: Doryctobracon areolatus (Szépligeti), Doryctobracon brasiliensis (Szépligeti), Utetes anastrephae (Viereck), Opius bellus (Wesmael) and Opius sp. (Wesmael), beyond the alisiíneo Asobara anastrephae (Muesebeck). Most of the braconids (77.5%) belonged to D. areolatus. This species was associated with the highest number of fruit tree species (26), in 7 families, and occurred in the majority of the cities sampled (30). It was associated to Anastrepha fraterculus (Wied.), A. obliqua (Macquart) and A. amita Zucchi, and it is recorded for the first time from fruit fly larvae in wampi, Clausena lansium (Lour) Skeels, and in &#34;canela-batalha&#34; fruits, Cryptocarya aschersoniana Mez. Doryctobracon brasiliensis was associated only to A. fraterculus, and it is recorded for the first time in fruit fly larvae in plum, Prunus salicina Lindl. It was not possible to associate the other parasitoid species to the fruit fly species. Opius sp. was associated with the fruit fly larvae in &#34;canela-batalha&#34; (first record of associate plant). The percentage of tephritid parasitism in the 33 cities was of 7.75%, varying from 0.02% to 40%. A key to identification for the braconid species was elaborated.

Page generated in 0.0788 seconds