Animal and Plant Health Inspection Service (APHIS), la primera autoridad encargada del control sanitario del Departamento de Agricultura de los Estados Unidos de Norteamérica, en el 2000 notificó la detención de embarques de espárrago fresco procedente de Perú con infestaciones de huevos y larvas de Copitarsia sp., ante este acontecimiento se estableció la fumigación con Bromuro de Metilo como requisito fitosanitario de los embarques de espárrago fresco peruano antes de su ingreso a los Estados Unidos. Sin embargo su uso excesivo está originando a la industria del espárrago fresco costos estimados de US$ 2.6 millones, pérdidas de calidad, reducción de tiempo de vida útil del producto y ruptura de la cadena de frío. Pogue y Simmons en el 2008 dieron a conocer una nueva especie, Copitarsia corruda, antes considerada Copitarsia decolora (Simmons y Pogue 2004), debido a que son especies crípticas, pero en la morfología interna (genitalia) y a nivel molecular, son distintas. Por tanto se busca implementar alternativas de control de esta especie, usando un controlador biológico del género Trichogramma, parasitoide principalmente de huevos de Lepidópteros. Por tal razón, en el presente trabajo de investigación se propuso realizar pruebas experimentales en el Laboratorio de Ensayos bajo condiciones ambientales normales para determinar la actividad parasítica del género Trichogramma sobre huevos de Copitarsia corruda, ya que tiende a matar a la plaga antes de que cause daño sobre los cultivos de espárrago. El objetivo principal de la investigación es evaluar la eficiencia de ocho especies de Trichogramma (T. atopovirilia, T. cacoeciae, T. dendrolimi, T. exiguum, T. galloi, T. nerudai, T. pintoi y T. pretiosum) sobre huevos de Copitarsia corruda. Por tanto, los resultados sugieren que T. nerudai y T. galloi son los más eficientes en comparación al resto de especies parasitoides del mismo género. Palabras claves: Copitarsia corruda, Trichogramma, Parasitoide, Espárrago, eficiente, oviposición. / *** Animal and Plant Health Inspection Service (APHIS), the First Authority of sanitary control of the Department of Agriculture of the United States of North America, in 2000 reported the detention of shipments of fresh asparagus from Peru with infestations of eggs and larvae of Copitarsia sp., before this event to established the fumigation with methyl bromide as phytosanitary requirement shipments of Peruvian fresh asparagus before coming to the United States. But overuse is giving rise to fresh asparagus industry estimated costs of $ 2.6 million, loss of quality, reduction of shelf life of the product and rupture of the cold chain. Pogue and Simmons in 2008 released a new species, Copitarsia corruda, once considered Copitarsia decolora (Simmons y Pogue 2004), because they are cryptic species, but internal morphology (genitaly) and molecular level are different. Therefore seeks to implement alternative control of this species, using a biological control agent of the genus Trichogramma parasitoid of eggs lepidoptera mainly. For this reason, in this research work is proposed to realize some experimental testing at the Test Laboratory under normal environment conditions to determine the parasitic activity of the genus Trichogramma on eggs Copitarsia corruda, as it tends to kill the pest before it causes damage on crops of asparagus. Therefore, the main objective of the research is to evaluate the efficiency of eight species of Trichogramma (T. atopovirilia, T. cacoeciae, T. dendrolimi, T. exiguum, T. galloi, T. nerudai, T. pretiosum and T. pintoi) on eggs Copitarsia corruda. The results suggest that T. nerudai and T. galloi are more efficient compared to other parasitoid species of the same genus. Keywords: Copitarsia corruda, Trichogramma, parasitoid, Asparagus, efficient. Oviposition.

Parasitoid insects face the fundamental problem of finding a suitable host in environments filled with competing stimuli. Many are deft sensors of olfactory cues emitted by other insects and the plants they live on, and use these cues to find hosts. Using olfactory cues from host-plants is effective because plants release volatile organic compounds (VOCs), in response to herbivory or oviposition, that contain information about the presence of hosts. However, plant-produced cues can also be misleading because they are influenced by a variety of stimuli (abiotic variation, infection and multiple sources of induction via herbivory or oviposition). Flexible behavior is one strategy that parasitoids may use to cope with variation in olfactory cues. We examine the innate and learned responses of a natural population of wasp egg parasitoids (Trichogramma deion and Trichogramma sathon) using a series of laboratory and field Y-olfactometer experiments. Wasps typically attack eggs of the hawkmoth Manduca sexta and Manduca quinquemaculata on native Datura wrightii plants in the southwestern United States. We show that Trichogramma wasps responded innately to VOCs produced by D. wrightii and could distinguish plants recently attacked by M. sexta from non-attacked plants. Furthermore, adult Trichogramma wasps were able to learn components of the VOC blend given off by D. wrightii, though they did not learn during exposure as pupae. By further exploring the behavioral ecology of a natural population of Trichogramma, we gain greater insight into how egg parasitoids function in tri-trophic systems.

Submitted by Nathália Faria da Silva (nathaliafsilva.ufv@gmail.com) on 2017-07-10T17:36:54Z No. of bitstreams: 1 texto completo.pdf: 378299 bytes, checksum: 6cef05158c7365fb4f508301b686eb61 (MD5) / Made available in DSpace on 2017-07-10T17:36:54Z (GMT). No. of bitstreams: 1 texto completo.pdf: 378299 bytes, checksum: 6cef05158c7365fb4f508301b686eb61 (MD5) Previous issue date: 2001-07-31 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Este trabalho avaliou o potencial de controle de três espécies de Trichogramma em ovos de lepidópteros desfolhadores de eucalipto e sua associação com percevejos pedadores. Foram avaliados a taxa de parasitismo, a viabilidade, a razão sexual, o número de indivíduos por ovo, a duração do período embrionário e a longevidade das fêmeas descendentes em ovos de Oxydia vesulia Cramer (Lepidoptera: Geometridae), das três espécies de parasitóide estudadas, apenas Trichogramma acacioi Brun e Trichogramma maxacalii Voegelé & Pointel (Hymenoptera: Trichogrammatidae) parasitaram ovos desse hospedeiro. Em ovos com diferentes períodos embrionários, T. maxacalii foi capaz de parasitar ovos com um, três e cinco dias. Ovos de Thyrinteina arnobia (Stoll) (Lepidoptera: Geometridae) não foram parasitados por T. acacioi, T. maxacalii e Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) e após 24 horas de contato com os ovos, todas as fêmeas desses parasitóides estavam mortas. No entanto, quando se lavou os ovos desse mesmo lepidóptero com solução xilol a 0,1%, somente 30% dos parasitóides estavam mortos após 24 horas. O estudo de comportamento de Podisus maculiventris (Say) (Heteroptera: Pentatomidae) por ovos de Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) parasitados ou não por Trichogramma brassicae (Bezdenko) (Hymenoptera: Trichogrammatidae), mostrou que esse predador prefere ovos dispostos em forma quadrangular, assemelhando-se a uma larva, e ovos não parasitados. / The objective of this research was to evaluate the potential of three Trichogramma species as biological control agents of eggs of Lepidoptera dofoliators of Eucalyptus and its association with predatory Pentatomidae. Parasitism rate, viability, sex ratio, number of individuals per egg, duration of the embryonic period and longevity of descendant females of these species were evaluated in eggs of Oxydia vesulia Cramer (Lepidoptera: Geometridae) for the parasitoids Trichogramma acacioi Brun, Trichogramma maxacalii Voegelé & Pointel (Hymenoptera: Trichogrammatidae) and Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae). Only the first and the second species parasitised eggs of this host. T. maxacalii parasitised one, three and five days old eggs of this host. On the other hand eggs of Thyrinteina arnobia (Stoll) (Lepidoptera: Geometridae) were not parasitised by T. acacioi, T. maxacalii and T. pretiosum even after 24 hours of contact with them when all parasitoid individuals died. However, washed eggs with xylol solution at 0.1% showed only 30% of dead parasitoids after 24 hours. Podisus maculiventris (Say) (Heteroptera: Pentatomidae) prefers to feed on Anagasta kuehniella (Zeller) (Lepidoptera: Pyralidae) eggs arranged in a square form which resembles larva of Lepidoptera when they were parasitised or not by Trichogramma brassicae (Bezdenko) (Hymenoptera: Trichogrammatidae).

Made available in DSpace on 2018-08-01T22:35:02Z (GMT). No. of bitstreams: 1 tese_7187_Victor Dias Pirovani20170112-102859.pdf: 3330538 bytes, checksum: 9c4ceb26baf33a465811f4227bca720f (MD5) Previous issue date: 2016-02-25 / A lagarta exótica do morangueiro, Duponchelia fovealis Zeller (Lepidoptera: Crambidae) tem causado grandes perdas no Brasil e no Espírito Santo desde sua introdução em 2010. Dessa forma, é necessário que métodos de manejo sejam estudados visando o controle da praga, já que essas informações são escassas para a condição de cultivo do morangueiro no país. Assim, os objetivos desse estudo foram: (1) determinar a melhor espécie de Trichogramma, sua densidade de liberação, capacidade de dispersão e número de pontos de liberação para o controle biológico de ovos de D. fovealis em sistema de cultivo do morangueiro em túnel baixo na região serrana do Espírito Santo; (2) estudar a virulência do nematoide entomopatogênico (NEP) Steinernema carpocapsae aos diferentes estágios de desenvolvimento de D. fovealis, bem como o efeito da temperatura na sua ação e estabelecer a CL50 para as fases suscetíveis; e (3) avaliar a eficiência do feromônio sexual sintético e a melhor armadilha para captura de machos da praga. A partir dos resultados, a melhor espécie é Trichogramma pretiosum na densidade de quatro parasitoides por ovo da praga. A capacidade de dispersão é de 14,21 metros lineares. É recomendada a liberação de 93.000 fêmeas por hectare a cada três dias. A distância entre os pontos de liberação do parasitoide é determinada pelo comprimento do túnel dividido por 14,21; em relação ao NEP, D. fovealis é suscetível na fase de pré-pupa e lagarta. Temperaturas entre 27º e 30ºC aumentam a eficiência do nematoide. A CL50 é de 71 e 75 JIs/inseto para a fase de larva e pré-pupa, respectivamente. Com base nos estudos com o feromônio sexual, a eficiência verificada é de seis semanas (cerca de 40 dias) para o monitoramento da praga, independente da estação do ano (inverno ou verão). A associação com a armadilha do tipo nudemafi apresenta eficiência e menor custo. O manejo de D. fovealis pode ser realizado com a associação dos métodos estudados.

The effective dispersal ability of the egg parasitoid Trichogramma ostriniae Pang and Chen was assessed in potato fields on the Eastern Shore of Virginia in spring 2005 and 2006. Approximately 0.5 million T. ostriniae were released from a central release point in separate potato fields. Dispersal was monitored using yellow sticky card traps and European corn borer, Ostrinia nubilalis Hübner, egg mass sentinels. Adult T. ostriniae dispersed quickly throughout the 0.4 ha (1 acre) sampling area. Parasitism and sticky card captures were highest close to the release point and decreased with increasing distance. Sticky card data were a good fit to the diffusion model used (r² > 0.90) for all but two sampling dates. In 2005 parasitization peaked at 4 days post release with close to 40% of sentinels parasitized at 30m from the release point. The mean distance encompassing 98% (x98) of T. ostriniae for both fields in 2005 was 27.5 (± 2.4) meters. For fields 1 and 2 in 2005, x98 for parasitism was 21 and 26 meters, respectively. In 2006 sticky card data fit the dispersal model moderately well (r² > 0.77) except for two sampling dates and dispersal was generally lower. The mean x98 value for sticky card data was 12.9 (± 0.9) meters. For parasitism, the x98 distances for field 1 and 2 were estimated at 8 and 10 meters, respectively. Correlation analysis showed no significant difference in the distributions between sticky card captures and sentinel egg mass parasitism. In 2006, T. ostriniae were released in small pepper plots in Pennsylvania, Maryland and two locations in Virginia to evaluate the number of wasps needed per plant for effective control of European corn borer. Treatments included 0, 5, 20 and 50 wasps per plant. In each plot, parasitism was measured using 30 sentinel egg masses collected on 3 and 6 days post release. Parasitism was relatively low in Pennsylvania and Virginia and no significant effect from release density was observed. High rates of parasitization in the untreated control plot were observed in Maryland as well as one of the Virginia locations. Overall results show results show ambiguity in the data and high levels of natural parasitism occurring on Ephestia eggs sentinels. In 2005 and 2006, several insecticides were evaluated for controlling O. nubilalis and impacting arthropod natural enemies in bell pepper. In addition, we compared the effectiveness of an integrated pest management program based around inundative releases of T. ostriniae to a conventional insecticide-based program for O. nubilalis control in multiple locations in the Mid- Atlantic US. To evaluate the insecticides, small plots of bell pepper were established at four locations in Virginia, Maryland, Delaware, and Pennsylvania. Insecticides were applied weekly from first fruit until final harvest (5 to 7 applications). Results indicated that the biorational insecticides, spinosad, indoxacarb, and methoxyfenozide provided comparable control of O. nubilalis as the broadspectrum conventional insecticides, acephate, and lambda-cyhalothrin. At most locations, multiple sprays of lambda-cyhalothrin resulted in flares (outbreaks) of green peach aphids most likely from destruction of arthropod natural enemies. Indoxacarb also caused a similar aphid flare at one of the locations. For the IPM demonstration experiment, pepper plots were established at 5 locations in the Mid-Atlantic U.S. in 2005 and 2006. Treatments included: "conventional", which involved weekly applications of acephate or lambda-cyhalothrin from first fruit until final harvest; 2) "IPM", which included three or four inundative releases of T. ostriniae and a judicial application of methoxyfenozide only if lepidopteran pests exceeded action thresholds; and 3) an untreated control. No significant treatment effect was found in either year on cumulative number of marketable fruit or percentage of fruit damaged by lepidopteran pests. A significant treatment effect was found on peak numbers of green peach aphids, with the conventional insecticide approach causing aphid flares and the untreated control or IPM approach not having aphid pest problems. Inundative releases of T. ostriniae may be a more environmentally-sound approach to managing O. nubilalis in peppers, although a comparison with conventional insecticides under greater lepidopteran pest pressure is still needed. / Master of Science in Life Sciences

Orientador: Regiane Cristina Oliveira de Freitas Bueno / Banca: José Roberto Postali Parra / Banca: Valmir Antonio Costa / Banca: Sandra Regina Magro / Banca: Pedro Takao Yamamoto / Resumo: A soja (Glycine max) é uma das culturas mais importantes no agronegócio brasileiro. Um dos principais problemas fitossanitários ocorrentes nesse cultivo é o ataque de insetos-praga, que estão presentes desde a emergência da plântula até a fase de colheita. O controle desses insetos é realizado a partir de inseticidas sintéticos. Porém, a tática de controle biológico tem sido cada vez mais utilizada no Brasil, tornando-se uma importante ferramenta no Manejo Integrado de Pragas (MIP). Entre as opções, o parasitoide de ovos Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) reduz a infestação de populações de insetos-praga da ordem Lepidoptera, propiciando menor impacto ambiental e a produção de alimentos mais saudáveis. Com isso, o presente trabalho verificou as características bioecológicas de T. pretiosum em espécies de Heliothinae, como também avaliou diferentes quantidades e formas de liberação deste parasitoide, demostrando o seu papel no manejo de lepidópteros-praga na cultura da soja. Para atingir este objetivo a tese foi dividida em quatro capítulos: (1) características biológicas e exigências térmicas de T. pretiosum em três espécies de Heliothinae; (2) capacidade de parasitismo de T. pretiosum em três espécies de Heliothinae sob diferentes temperaturas; (3) técnicas de liberação de T. pretiosum para o controle de lepidópteros-praga da soja; (4) manejo integrado de insetos-praga na cultura da soja com e sem controle biológico. No laboratório avaliou-se o pot... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The Soybean (Glycine max) is one of the most important crops in Brazilian agribusiness. One of the main phytosanitary problems occurring in this crop is the attack of insect pests, which are present from the emergence of the seedling until the harvest. The control of these insects is carried out from synthetic insecticides. However, the biological control tactic has been increasingly used in Brazil, becoming an important tool in Integrated Pest Management (IPM). Among the options, the Trichogramma pretiosum Riley (Hymenoptera: Trichogrammatidae) is a parasitoid egg reduces the infestation of populations of insect pests of the order Lepidoptera, providing less environmental impact and the production of healthier foods. Thus, the present work verified the bioecological characteristics of T. pretiosum in Heliothinae species, as well as evaluating different amounts and forms of release of this parasitoid, demonstrating its role in the management of lepidopteran pests in the soybean crop. To achieve this objective the thesis was divided into four chapters: (1) biological characteristics and thermal requirements of T. pretiosum in three species of Heliothinae; (2) the parasitism capacity of T. pretiosum in three Heliothinae species under different temperatures; (3) techniques for the release of T. pretiosum for the control of lepidopteran pests of soybean; (4) integrated pest-insect management in soybean crop with and without biological control. In the laboratory the potential of t... (Complete abstract click electronic access below) / Doutor

Made available in DSpace on 2016-12-23T14:37:34Z (GMT). No. of bitstreams: 1 ALEXANDRE FARIA DA SILVA.pdf: 219267 bytes, checksum: 28ddb1dee1224cc16a8be4a2ae00c095 (MD5) Previous issue date: 2007-02-28 / This research had as objective selects a type of Trichogramma created in eggs of D. nitidalis (Cramer 1782) for a possible biological control of this curse. The experiment was driven in the Nucleus of development researches and Technology in the Fitossanitario handling in the Control of Prague and Diseases (NUDEMAFI) of the Center of Agrarian Sciences of Espírito Santo Federal University (CCA-UFES), in acclimatized room the a temperature of 25±1 ºC, relative humidity of 70±10% and fotofase of 14 hours. The females of the species of Trichogramma pretiosum, T. exiguum and T. atopovirilia were individualized in glass tubes, which cardboard cartelas was put with 25 eggs of the day of D. nitidalis, being allowed a parasitism by 24 hours. The percentage of parasitism went significantly larger for T. pretiosum (25,66) while for T. exiguum that value was 2,2 times inferior, already for T. atovirllia there was not parasitism on eggs of D. nitidalis. The T. pretiosum was who presented a larger potential of control of D. nitidalis in the temperature of 25ºC. In a second stage, it was evaluated the biology and thermal demands of Trichogramma pretiosum Riley created in eggs of Diaphania nitidalis Cramer under different temperatures. Initially, eggs of D. nitidalis were submitted to the parasitism of T. pretiosum, for five hours in the temperature of 25oC, being transferred then for acclimatized cameras regulated for the temperatures of 18, 21, 24, 27, 30 and 33 1oC. The duration of the cycle (egg-adult) it was influenced by the temperatures varying from 7,75 to 27,5 days for T. pretiosum. The percentage of emergency of T. pretiosum was higher in the strip of temperatures among 21 to 30ºC, with values equal to 100%, in the temperatures extreme 18 and 33ºC they provided smaller emergency taxes. The parasitóides number emerged by egg of D. nitidalis varied in function of the temperatures, where it was obtained 1,6 individuals by egg to 24ºC, while in the other temperatures the value was same to 1,0. The sexual reason didn't suffer influence in function of the temperatures. In relationship the thermal demands, the temperature base (Tb) and the thermal constant (K) of T. pretiosum in eggs of D. nitidalis, the obtained values were 11,45ºC and 170,89 degrees days. I number him/it dear of annual generations of T. pretiosum in Spirit Santo maximum minimum strips they varied of 5,45 and 41,76ºC in the temperatures of 14 and 31ºC. The satisfactory performance of T. pretiosum created in eggs of it presented a D. nitidalis in the temperatures varying from 21 to 30ºC, it allows the recommendation of that parasitóide as potential in the control of this curse. / Esta pesquisa teve como objetivo selecionar a(s) espécie(s) de Trichogramma criados em ovos de Diaphania nitidalis Cramer (1782) (Lepidoptera: Pyralidae) para um possível controle biológico desta praga. O experimento foi conduzido no Núcleo de Desenvolvimento Cientifico e Tecnológico e Manejo Fitossanitário de Pragas e Doenças (NUDEMAFI) do Centro de Ciências Agrárias da Universidade Federal do Espírito Santo (CCAUFES), em sala climatizada a uma temperatura de 25±1ºC, umidade relativa de 70±10% e fotofase de 14 horas. As fêmeas das espécies de richogramma pretiosum Riley (1879) (Hymenoptera: Trichogrammatidae), Trichogramma exiguum Pinto & Platner (1978) (Hymenoptera: Trichogrammatidae) e Trichogramma atopovirilia Oatman & Platner (1983) (Hymenoptera: Trichogrammatidae) foram individualizadas em tubos de vidro, os quais foram colocadas cartelas de cartolina com 25 ovos do dia de D. nitidalis, sendo permitido um parasitismo por 24 horas. A porcentagem de parasitismo foi significativamente maior para T. pretiosum 25,66% enquanto que para T. exiguum esse valor foi 2,2 vezes inferior, já para T. atovirllia não houve parasitismo sobre ovos de D. nitidalis. T. pretiosum foi a espécie que apresentou maior potencial de controle de D. nitidalis na temperatura de 25ºC. Na segunda etapa, avaliou-se a biologia e exigências térmicas de T. pretiosum criados em ovos de D. nitidalis sob diferentes temperaturas. Inicialmente, ovos de D.nitidalis foram submetidos ao parasitismo de T. pretiosum, durante cinco horas na temperatura de 25oC, sendo então transferidos para câmaras climatizadas reguladas para as temperaturas de 18, 21, 24, 27, 30 e 33±1oC. A duração do ciclo (ovo-adulto) foi influenciada pelas temperaturas variando de 7,75 a 27,5 dias para T. pretiosum. A percentagem de emergência de T. pretiosum foi mais elevada na faixa de temperaturas entre 21 a 30ºC, com valores iguais a 100%, sendo que nas temperaturas extremas (18 e 33ºC) proporcionaram menores taxas de emergência. O número de parasitóides emergidos por ovo de D. nitidalis variou em função das temperaturas, onde se obteve 1,6 indivíduos por ovo a 24ºC, enquanto que nas demais temperaturas o valor foi igual a 1,0. A razão sexual não sofreu influência em função das temperaturas. Em relação as exigências térmicas, a temperatura base (Tb) e a constante térmica (K) de T. pretiosum em ovos de D. nitidalis, os valores obtidos foram 11,45ºC e 170,89 graus dias respectivamente. O número estimado de gerações anuais de T. pretiosum nas emperaturas mínimas e máximas do Espírito Santo variaram de 5,45 e 41,76ºC nas temperaturas de 14 e 31ºC. A performance satisfatória de T. pretiosum criados em ovos de D. nitidalis, nas temperaturas variando de 21 a 30ºC, permite a recomendação desse parasitóide como potencial no controle desta praga.

Trichogramma limit pest damage to Ord River Irrigation Area (ORIA) cotton crops by killing the developing embryo of their insect host at the egg stage, effectively reducing the number of emergent pests ingesting transgenic tissue. Their impact on the potentially resistant species, Helicoverpa armigera (Hübner), is considered integral to the Insect Resistance Management (IRM) strategy for transgenic cotton production in the ORIA. This thesis examines aspects of Trichogramma ecology pertinent to this strategy. The dominant species of egg parasitoid in ORIA cotton crops is the introduced Trichogramma pretiosum Riley. Other species make up less than one percent of collected specimens. Surveys revealed T. pretiosum has been introduced or adventitiously dispersed to all developed agricultural regions of northern Australia. Several new species were discovered during surveys in more pristine habitats. Based on field collected eggs, T. pretiosum appears to prefer H. armigera over H. punctigera Wallengren as a host in ORIA cotton. Measured as percent parasitism, Trichogramma activity appears highly variable and does not necessarily coincide with periods of peak insect pest density. Host abundance alone does not define conditions suitable for Trichogramma activity. Environmental constraints on wasp survival, such as the impact of temperature, humidity and insecticide applications, limit their effectiveness in biological control. Despite consistently high rates of percentage egg parasitism (60-99%), acceptable pest control is not readily achieved in ORIA cotton without the aid of insecticides as Helicoverpa numbers exceed damage thresholds. Insecticides inhibit Trichogramma considerably, hence the conundrum regarding initiation of insecticidal control. Trichogramma activity is relatively high early season (May to July), significantly limiting the buildup of pests. Trichogramma effectively stifle Helicoverpa population increase following initial pest egg lay at least during high density years. The impact of farming practices, especially insecticide applications, should be avoided early season to ensure pest mortality attributed to Trichogramma egg parasitisation is maximised. Pre-season habitat manipulation to establish large populations of Trichogramma in alternative hosts is advised. Despite being rare in surrounding habitats and suffering near 50% immature mortality in the field, Trichogramma effectively disperse into young crops attractive to ovipositing hosts and display a high intrinsic rate of increase. Spatial patterns of parasitism tend toward heterogeneity and do not necessarily coincide with host spatio-temporal dynamics. Both host abundance patterns and mean rates of parasitism are not good indicators of parasitoid patchiness. Parasitism rates are highest within the middle strata of the plant canopy prior to complete canopy closure despite a similar number of host eggs being available elsewhere in the plant. Pest density declines as the season progresses. However, insecticide applications become necessary if Bt expression in cotton plants wanes and larval damage increases. Measuring parasitism during periods of declining and low host density is prone to inaccuracy due to small sample size, but can be overcome with the use of egg cards. A better indication of parasitoid activity is achieved using egg cards during periods when insecticide applications are possibly required. As Trichogramma are most active in ORIA cotton from morning to early afternoon, insecticide applications if needed should occur outside of these periods. Trichogramma survival is constrained by environmental influences. Adult female T. pretiosum were exposed to ambient conditions in dialysis tubing sleeve cages to test survival and fecundity in cotton fields. Peak survival and fecundity occurs mid season with both life history variants displaying an inverse relationship to temperature. Adult female T. pretiosum survive longest in the field when provided with sustenance however mortality attributed to handling was considerable. Sleeve cages are not effective for survival measurement of small parasitoids if the cages are frequently moved. Trichogramma effectively reduce pest abundance but are clearly hindered by insecticides and hot dry conditions in ORIA cotton crops. The decision to initiate insecticide applications is best delayed unless absolutely necessary to avoid disruption of Trichogramma impact on pests. Parasitoid activity must be carefully monitored if chemical control becomes imminent. The impact of Trichogramma on pest species can then be optimally exploited.

Made available in DSpace on 2014-06-11T19:25:18Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-22Bitstream added on 2014-06-13T18:53:10Z : No. of bitstreams: 1 goulart_rm_me_jabo.pdf: 523747 bytes, checksum: f0fe3c45844cc1e1132f204073faeebd (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O objetivo do presente trabalho foi avaliar a seletividade dos inseticidas triflumurom, etofenproxi e endossulfam a duas espécies de Trichogramma, T. pretiosum e T. exiguum em ovos de três diferentes hospedeiros, Anagasta kuehniella, Spodoptera frugiperda e Plutella xylostella em condições de laboratório. Os experimentos de seletividade desenvolvidos no Laboratório de Biologia e Criação de Insetos da Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal UNESP foram realizados mediante a utilização de duas metodologias: uma nova metodologia proposta no LBCI, onde foram avaliados o número de ovos parasitados, porcentagem de parasitismo, porcentagem de emergência, longevidade e razão sexual das gerações F1 e F2 dos parasitóides, e no segundo experimento, utilizando-se da metodologia preconizada pela IOBC, foram avaliados o número de ovos parasitados, porcentagem de parasitismo, porcentagem de emergência e redução no parasitismo. Observou-se que nas duas metodologias os inseticidas endossulfam e etofenproxi não mostraram seletividade aos parasitóides, matando ou inibindo a oviposição, independente do hospedeiro utilizado. Triflumurom mostrou-se seletivo aos parasitóides somente em ovos de hospedeiros naturais quando a nova metodologia (LBCI) foi utilizada. Em testes com a metodologia da IOBC/WPRS triflumurom mostrou-se seletivo às duas espécies de parasitóides, não interferindo nos parâmetros biológicos; entretanto a utilização dessa metodologia interferiu nos resultados quando mais de uma espécie foi utilizada na realização dos experimentos, sendo passível de questionamento. / The aim of this work was to evaluate the selectivity of pesticides triflumurom, etofenprox and endosulfan for two species of Trichogramma; T. pretiosum and T. exiguum, in different hosts: A. kuehniella, S. frugiperda and P. xylostella, under laboratory conditions. The research was conducted at Faculdade de Ciências Agrárias e Veterinárias de Jaboticabal (FCAV-UNESP), in the Laboratório de Biologia e Criação de Insetos. The tests were based on two methodologies: a new methodology for selectivity tests which was developed in LBCI and the IOBC/WPRS methodology. Using LBCI methodology parasitized eggs, percentage of emergence, percentage of parasitism, longevity and sex ratio were evaluated for generations F1 and F2. Using IOBC methodology were evaluated parasitized eggs, percentage of emergence, percentage of parasitism and parasitism reduction. The endosulfan and etofenprox were harmful to parasitoids inhibiting the parasitism in all hosts or killing the insects by two methodologies. Triflumurom was selective to parasitoids just in natural host eggs when the new methodology was applied. When the IOBC methodology was applied triflumurom showed selectivity for both species of parasitoids but the use of more than one specie of parasitoid using this methodology influenced the results being this methodology passible for discussions.

Submitted by (edna.saturno@ufrpe.br) on 2016-11-24T15:08:38Z No. of bitstreams: 1 Gilberto Santos Andrade.pdf: 539005 bytes, checksum: 575c35c9686dfc82cb2bf5b3882e07f1 (MD5) / Made available in DSpace on 2016-11-24T15:08:38Z (GMT). No. of bitstreams: 1 Gilberto Santos Andrade.pdf: 539005 bytes, checksum: 575c35c9686dfc82cb2bf5b3882e07f1 (MD5) Previous issue date: 2007-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / One important aspect of maximizing pest natural mortality factors is to enhance the action of natural enemies into integrated pest management programs. Species of the egg parasitoid Trichogramma have been investigated and used successfully around the world. To boost the utilization of these parasitoids as biological control agent, basic studies on species selection regarding the interactions with environmental conditions and host plants is needed. In Brazil, Trichogramma pretiosum Riley is recommended to control lepidopteran pests of cotton. Thus, this research evaluated the potential of other three Trichogramma species in comparison to T. pretiosum parasitizing eggs of tobacco budworm Heliothis virescens (Fabr.) under constant (20, 25 and 30oC) and alternated (immature development at 25oC and adult submitted to 20 and 30oC) temperatures. Additionally, the best performing species at these temperature regimes were tested when offering egg of the host tobacco budworm on cotton leaves of two varieties (ca. colored BRS Safira and white fibers BRS 8H). The species studied were: Trichogramma exiguum Pinto & Platner, Trichogramma atopovirilia Oatman & Platner, Trichogramma acacioi Brun, Moraes & Soares and T. pretiosum. The evaluated parameters were: parasitism rate and its viability, sex ratio of the progeny and number of descendents emerged per egg parasitized. Overall, T. atopoviriliaexhibited the best performance through all temperature regimes studied. T. pretiosum and T.exiguum achieved similar parasitism rate of H. virescens eggs, while T. acacioi showed the lower performance. Based on the results above, parasitism of eggs offered on cotton leaves was conducted with the species T. exiguum, T. pretiosum and T. atopovirilia. The cotton variety affected the parasitism rate of T. exiguum and T. atopovirilia resulting in lower parasitism when eggs were offered on BRS Safira cotton leaves, but it was similar for T. pretiosum. Therefore, under constant and alternating temperatures and host exposure on cotton leaves all species parasitized eggs of H. virescens, but T. atopovirilia exhibited better performance in comparison to the others. Therefore, further studies should be conducted looking for other field aspects related with the use of this parasitoid such as dispersion and field parasitism. / Espécies do gênero Trichogramma têm sido pesquisadas em todo o mundo para o controle biológico de lepidópteros-praga. Para que a eficiência desses parasitóides seja aumentada faz-se necessário a realização de estudos básicos visando à seleção de espécies em relação ao ambiente e seus hospedeiros. No Brasil, a espécie Trichogramma pretiosum Riley é a mais utilizada para o controle de lepidópteros-praga do algodoeiro. Assim, comparou-se o desempenho de outras espécies tais como: Trichogramma exiguum Pinto & Platner, Trichogramma atopovirilia Oatman & Platner e Trichogramma acacioi Brun, Moraes & Soares (Hym.: Trichogrammatidae) parasitando ovos de Heliothis virencens (Fabr.) (Lep.: Noctuidae) sob temperaturas constantes (20, 25 e 30oC) e alternadas (fase imatura a 25oC e adultos submetidos a 20 e 30oC para parasitismo). Adicionalmente, as espécies com melhor desempenho nas temperaturas estudadas foram testadas oferecendo ovos de H. virescens em folhas de algodoeiro das cultivares BRS 8H e BRS Safira. As variáveis avaliadas foram: porcentagem de parasitismo e viabilidade; razão sexual e número de indivíduos por ovo. T. atopovirilia foi a espécie com melhor desempenho em todas as condições térmicas estudadas constatado através da maior porcentagem de parasitismo. T. pretiosum e T. exiguum apresentaram a mesma taxa de parasitismo em ovos de H. virescens e T. acacioi obteve a menor taxa de parasitismo. Com base nesses resultados, o estudo oferecendoovos em folhas das duas cultivares de algodoeiro foi conduzido com T. exiguum, T. pretiosum e T. atopovirilia. As cultivares de algodoeiro afetaram o parasitismo de ovos de H. virescens de T. atopovirilia e T. exiguum, sendo inferior quando os ovos foram oferecidos em folhas de BRS Safira. Não houve efeito das cultivares no parasitismo de H. virescens por T. pretiosum. Os resultados evidenciam que T. atopovirilia e T. exiguum apresentaram melhor parasitismo de ovos depositados em BRS 8H e o parasitismo de T. atopovirilia foi superior aquele de T. pretiosum quando ovos encontravam-se sobre a cultivar BRS Safira. Assim, futuros estudos devem ser conduzidos com T. atopovirilia parasitando ovos de H. virescens em condição de campo e onde sejam analisadas variáveis como quantidade de parasitóides a serem liberados para a obtenção de taxas de parasitismo satisfatórias.