Cleaner fish, including ballan wrasse (Labrus bergylta) have been proposed as a sustainable solution to sea lice infestations affecting farmed Atlantic salmon (Salmo salar) globally. However, in order to become sustainable, ballan wrasse need to be farmed. This thesis investigated the establishment of captive broodstock and protocols to optimise hatchery performance and productivity of ballan wrasse. High throughput sequencing was used to develop a panel of novel single nucleotide polymorphic markers (SNPs). These SNPs were used to investigate the phylogeographic structuring of ballan wrasse populations within northern geographic ranges including the UK and Norway. Results indicated fine scale population structuring within the UK suggesting that founder broodstock should be sourced locally to minimise the risk of genetic introgression with wild ballan wrasse. Secondly, captive breeding was benchmarked from harems to determine total egg production over the spawning season. Data quantified the spawning periodicity and seasonal changes in egg quality parameters. In addition, microsatellite markers identified the parental contribution to each spawning event of captive broodstock. Results confirmed, for the first time, the repeat-batch spawning behaviour and suggested that spawning events were single-paired matings. Furthermore, bottlenecks in commercial production were investigated including the benthic adhesive eggs and complex spawning behaviours of ballan wrasse within broodstock tanks. Experiments were conducted to optimise the spawning dynamics and egg productivity using fragmented spawning zones and coloured substrates. Finally, an effective bath treatment for removal of the adhesive gum layer of eggs using the proteolytic enzyme alcalase® was found to assist in egg disinfection and incubation. Overall, this research provides important baseline data on the management of broodstock and the optimisation of hatchery protocols to improve the commercial productivity and performance of ballan wrasse for use as a biological control of sea lice of farmed Atlantic salmon.

Made available in DSpace on 2015-03-26T12:36:04Z (GMT). No. of bitstreams: 1 texto completo.pdf: 676402 bytes, checksum: a5b1799aa7d49fbc648126a5b6da326b (MD5) Previous issue date: 2014-02-28 / O ácaro-branco Polyphagotarsonemus latus (Banks, 1904) (Acari: Tarsonemidae) é uma praga chave de distribuição mundial que ataca várias espécies de plantas de alto valor econômico. No Brasil, este ácaro é considerado praga chave da cultura de pimenta malagueta e do pinhão manso, devido a sua frequente ocorrência em areas produtoras e aos danos causados. Na maioria das vezes seu controle é baseado na aplicação de produtos químicos, com todos os problemas derivados de seu uso abusivo. Uma alternativa ao controle químico é o uso do controle biológico. Os principais inimigos naturais dos ácaros fitófagos são ácaros da família Phytoseiidae. Vários inimigos naturais hão sido registrados em associação com o ácaro-branco no Brasil, os fitoseídeos (Amblyseius herbicolus, Neoseiulus barkeri, Euseius concordis, Iphiseiodes zuluagai and Typhlodromus transvaalensis) e uma espécie da família Blattisociidae (Lasioseius floridensis). Como um primeiro passo para a seleção de agentes de controle biológico para o ácaro-branco, foram avaliadas as taxas de predação e oviposição das espécies A. herbicolus, N. barkeri e L. floridensis em duas situações: uma mistura dos estádios do ácaro-branco e em todos os diferentes estádios da praga. Num segundo passo, foi avaliado em condições de casa de vegetação, a eficiência dos fitoseídeos, A. herbicolus e N. barkeri, no controle do ácaro branco em pimenta malagueta em diferentes relações predador: presa. Num segundo experimento, foi avaliado o controle em plantas de pimenta malagueta infestadas com o ácaro-branco, com e sem liberação de predadores e seu impacto na produção de frutos. Um terceiro passo, foi avaliado o controle do ácaro- branco em plantas de pinhão manso e pimenta malagueta infestadas artificialmente com a praga em condições de campo, com e sem liberação dos fitoseídeos e seu efeito na produção da pimenta malagueta. Nos experimentos de laboratório, os fitoseídeos predaram e ovipositaram quando se usou a mistura dos estádios do ácaro-branco e em cada um dos estádios. Amblyseius herbicolus apresentou uma maior taxa de predação e oviposição, nas duas situações avaliadas em comparação a N. barkeri. Entretanto, L. floridensis apresentou taxas de predação e oviposição baixas ou nulas nas duas situações avaliadas. Em casa de vegetação, A. herbicolus e N. barkeri controlaram as populações do ácaro-branco nas diferentes relações predador:presa; as plantas controle mostraram sintomas de um ataque severo sete dias após a infestação, incluindo a queda de folhas. No segundo experimento, os fitoseídeos mantiveram baixas as populações de ácaro-branco através do tempo. Assim mesmo, as plantas de pimenta malagueta com presença dos predadores apresentaram um maior número de frutos com maior peso do que as plantas controle. As plantas controle exibiram danos severos, incluindo queda de folhas. Em condições de campo, plantas de pinhão manso sem predadores exibiram altíssimas populações do ácaro-branco, sintomas severos, queda de folhas e altos valores na escala de notas de dano. Entretanto, plantas com predadores mostraram baixas populações da praga ao longo do tempo e não manifestaram sintomas severos. Em pimenta malagueta, as plantas sem predadores apresentaram maior número de ácaros-branco, curvamento e bronzeamento das folhas, porém a queda de folhas foi muito menor que registrada no experimento de casa de vegetação. Plantas de pimenta malagueta com presença de predadores exibiram baixo número de ácaros-branco e não apresentaram bronzeamento nem queda de folhas. Não houve diferença estatística no número e peso de frutos entre plantas de pimenta malagueta com e sem predadores, mas as plantas controle apresentaram frutos mais pequenos. Os predadores A. herbicolus e N. barkeri, foram efetivos no controle de populações do ácaro-branco nos diferentes passos avaliados neste estudo. As duas espécies predaram e ovipositaram ao se alimentar da praga. Em condições de casa de vegetação as plantas de pimenta malagueta foram beneficiadas pela presença dos predadores apresentando baixas populações da praga através do tempo, resultando na produção de frutos maiores e mais pesados. Em campo, os dois fitoseídeos tiveram a capacidade de manter em baixas densidades as populações do ácaro- branco no tempo, tanto em pinhão manso quanto em pimenta malagueta evitando o aparecimento de sintomas severos como os registrados nas plantas controle. Amblyseius herbicolus e N. barkeri podem ser considerados bons agentes de controle biológico do ácaro-branco. As duas espécies controlaram populações da praga em diferentes relações predador:presa, em condições de cultivo protegido e no campo. Os predadores conseguiram-se manter e aumentar em número no tempo, tanto em casa de vegetação quanto no campo, confirmando os resultados de laboratório. Adicionalmente, os predadores conseguiram aumentar seu número em baixas densidades de ácaro-branco, indicando que eles podem fazer uso de recursos alternativos como o pólen ou néctar das flores de pimenta malagueta. O potencial de controle destes fitoseídeos pode ser aproveitado em outras culturas susceptíveis ao ataque do ácaro-branco, como papaia, feijão, batata ou gérbera, tanto em casa de vegetação quanto em campo aberto. / The broad mite Polyphagotarsonemus latus (Banks 1904) is an important worldwide pest, with economic impact of several crops. In Brazil, this mite is considered a key pest of chili pepper and physic nut, due to their frequent occurrence in planting areas and damage caused to plant hosts. Its control is based on application of agrotoxics with several problems derived from misuse. An alternative to chemical control is biological control. The main natural enemies of phytophagous mites are predatory mites from the phytoseiidae family. Several natural enemies have been recorded in association with broad mites in Brazil, including the phytoseiids (Amblyseius herbicolus, Neoseiulus barkeri, Euseius concordis, Iphiseiodes zuluagai and Typhlodromus transvaalensis) and one blattisociid mite species (Lasioseius floridensis). As a first step to select biological control agents for broad mites, we evaluated the predation and oviposition rates of predatory mite of species A. herbicolus, N. barkeri and L. floridensis on a mixture of broad mite stages and on all different stages of the pest. As a second step, we evaluated under greenhouse conditions the phytoseiids A. herbicolus and N. barkeri on chili pepper with different predator:prey ratios. In a second experiment, we evaluated the control on chili pepper plants infested with broad mites, with and without predators and their impact on fruit production. In a third step, we assessed the control of broad mites on physic nut and chili pepper plants, artificially infested with the pest, under field conditions with and without phytoseiids and their effect on the chili pepper production. In laboratory experiments, the phytoseiids preyed and oviposited when offered a mix of broad mite stages or on each stage separately. Amblyseius herbicolus showed higher predation and oviposition rates on the mix of broad mite stages and on each stage separately compared with N. barkeri rates. Meanwhile, L. floridensis showed oviposition and predation rates low or zero on the mix of broad mite stages and on each stage separately. In the greenhouse, A. herbicolus and N. barkeri controlled broad mite population in the different predator:prey ratios; control plants showed symptoms of a severe attack seven days after infestation, including foliar abscission. In a second experiment, the phytoseiids maintained the broad mite populations at low density over time. Chili pepper plants with predators had a higher number of fruits with greater weight that control plants. Control plants showed higher values on scale notes of injury with severe damage, including foliar abscission. Under field conditions, physic nuts and chili peppers without predators showed a very high population of broad mites with higher values on scale notes of injury. These plants showed severe symptoms and foliar abscission. However, plants with predators showed a low population of pest through time with low values on scale notes of injury without presence of severe symptoms. In chili pepper, plants without predators had higher number of broad mite, curling and bronzing of leaves, but leaf fall was much lower than recorded in the greenhouse experiments. Chili pepper plants with predators showed low number of broad mites and showed no symptoms. There was no statistical difference in the number and weight of fruits from chili pepper plants with and without predators, but control plants had smaller fruits. The predators A. herbicolus and the Brazilian strain of N. barkeri showed effectivess in controlling broad mite populations on the different steps evaluated in this study. Both predators preyed and oviposited when feeding on the pest. Under greenhouse conditions, chili pepper plants were benefited by presence of predators, showing low populations of broad mites through time, resulting in the production of larger fruits with higher weight. In field, both phytoseiids had the ability to maintain broad mite populations on low density through time on physic nut and chili pepper plants, preventing the development of severe symptoms in the plants. Amblyseius herbicolus and N. barkeri can be considered good biological control agents of the broad mite. Both species controled pest populations with different predator:prey ratios in protected cultivation and in the field. Predators were able to maintained and increased on number through time when fed on broad mite, confirming the laboratory results. The potential of control of A. herbicolus and N. barkeri can be exploited in other crops susceptible to broad mite attack as bean, papaya, potato or gerbera, both on the greenhouse and open field conditions.

O equilíbrio entre insetos-praga e inimigos naturais existentes na cultura da soja, pode ser influenciado pelo manejo do solo, produtos fitossanitários e cultivares de soja. O presente estudo avaliou a diversidade de lepidópteros associados à cultura da soja, no continente Americano, e a abundância específica destes insetos e seus inimigos naturais (parasitóides e fungos entomopatogênicos), em soja convencional e transgênica RR, com aplicação de herbicidas seletivos (Amplo® e Aramo®) e uma formulação de glifosato (Gliz®), sendo o cultivo da soja BRS 133-convencional e BRS Charrua RR-transgênico realizado em Vacaria, RS, sob manejo de solo convencional, em três lotes de um hectare cada. Nas amostragens semanais, os lepidópteros foram coletados com pano-de-batida, mantidos em criação laboratorial até a obtenção dos adultos, dos parasitóides ou dos fungos entomopatogênicos. Também realizaram-se amostragens de solo para isolamento de fungos entomopatogênicos. Elaborou-se uma listagem dos lepidópteros associados à cultura da soja no continente Americano, relacionando-se 71 espécies cujas formas larvais já foram referidas alimentando-se de soja. No presente estudo foram coletadas 1634 larvas de lepidópteros identificados em 22 táxons, destacando-se Anticarsia gemmatalis, Pseudoplusia includens e Rachiplusia nu como as mais representativas (83,05% das larvas coletadas). A aplicação da formulação de glifosato afetou negativamente o número médio de lagartas em relação aos demais lotes tratados com herbicidas seletivos. Os himenópteros, dípteros e strepsípteros foram responsáveis pelo parasitismo de 34,52% das lagartas. Entretanto com relação ao parasitismo específico, observou-se que entre as lagartas parasitadas, 93,05% pertenciam às três espécies mais freqüentes, destacando-se os plusiíneos que foram mais parasitados que A. gemmatalis. N. rileyi foi o único fungo entomopatogênico isolado a partir de lagartas, sendo responsável por 1,41% da mortalidade das três espécies mais abundantes. Os números de unidades formadoras de colônias de Beauveria, Metarhizium e Paecilomyces, isolados das amostras de solo não diferiram estatisticamente entre os lotes. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-05-30T17:11:50Z No. of bitstreams: 1 Dissertacao Aline Carraro Formentini.pdf: 342643 bytes, checksum: 93c716533f6eda2fbf2bb806b35f1c62 (MD5) / Made available in DSpace on 2014-05-30T17:11:50Z (GMT). No. of bitstreams: 1 Dissertacao Aline Carraro Formentini.pdf: 342643 bytes, checksum: 93c716533f6eda2fbf2bb806b35f1c62 (MD5) / In soybean plantations, the equilibrium between insect pests and their natural enemies can be influenced by various factors such as soil management, use of phytosanitary products and soybean cultivar. This study evaluated the diversity of Lepidoptera associated with soybean crops in the Americas, and the specific abundance of these organisms and their natural enemies (parasitoids and entomopathogenic fungi) on conventional and transgenic RR soybean, treated with selective herbicides and glyphosate formulations. The experiment was carried out in Vacaria, Rio Grande do Sul state. Conventional BRS 133 and transgenic RR soy were each planted on three, one-hectare plots and treated with either selective herbicides or a glyphosate formulation. During weekly sampling, Lepidoptera were collected using the drop cloth method and maintained in the laboratory until adults and associated parasitoids and fungi could be obtained. Entomopathogenic fungi were isolated from soil samples. Based on literature data one list of 71 species of Lepidoptera that had been previously reported as feeding on soybean crop was prepared. In the present study, 1634 Lepidoptera larvae were identified in 22 taxa, including the following well-represented species: A. gemmatalis, P. includens e R. nu (83.05% of the larvae collected). The glyphosate treatments reduced the mean number of larvae when compared with the selective herbicide treatments. Hymenopterans, dipterans and strepsipterans were responsible for 34.52% of the total caterpillar parasitism. A large percentage of the larvae parasitized (93.05%) belong to the three most common species of Lepidoptera in our sampling, particularly to the Plusiinae, which were more heavily parasitized than A. gemmatalis. The entomopathogenic fungus N. rileyi was the only species isolated from the caterpillars and was responsible for 1.41% of the deaths amongst the three most common species. The numbers of colony-forming unities of Beauveria, Metarhizium and Paecilomyces, isolated from soil samples, did not differ among the plots.

Orientador: Antonio Carlos Busoli / Banca: Marcos Gino Fernandes / Banca: Nilza Maria Martinelli / Resumo: O conhecimento do comportamento de infestação dos insetos em sistemas agrícolas facilita as amostragens, economiza tempo sem perder a confiabilidade para a tomada de decisões no sistema de manejo de pragas. Assim o objetivo foi estudar a distribuição vertical e temporal de ovos de Alabama argillacea e de Heliothis virescens, e o parasitismo de ovos por Trichogramma pretiosum em cultivares de algodoeiro. O delineamento experimental foi em blocos ao acaso, com cinco tratamentos (cultivares DeltaOPAL, FMX-933, FMT-701, FMX-910 e NuOPAL), com oito repetições. As avaliações foram semanais, a partir da emergência das plantas. Para a distribuição vertical, as plantas foram avaliadas nas partes superior, média e inferior, anotando-se o número de ovos. Os ovos de A. argillacea e de H. virescens foram parasitados por Trichogramma pretiosum. Não houve preferência para oviposição por A. argillacea e por H. virescens durante os estágios fenológicos das plantas, tal como o grau de parasitismo por T. pretiosum também não foi influenciado. Quanto à distribuição vertical dos ovos, o terço superior e o médio das plantas foram os mais preferidos para oviposição por A. argillacea nas cultivares NuOPAL, DeltaOPAL e FMX-910, enquanto que H. virescens preferiu ovipositar no terço superior das plantas. T. pretiosum preferiu ovipositar em ovos de A. argillacea presentes no terço superior e médio das plantas, sendo que ovos de H. virescens presentes no terço superior das plantas foram mais parasitados por T. pretiosum / Abstract: The knowledge of a pest infestation behavior on agricultural areas help the sampling and reduce time without lose confidence on decisions in integrated pest management. This work aimed to study the vertical and temporal distribution of Alabama argillacea and Heliothis virescens eggs, as well as parasitism of its eggs by Trichogramma pretiosum in cotton cultivars. The experimental design was randomized blocks with five treatments with five treatments (cultivars DeltaOPAL, FMX-933, FMT-701 and FMX-910 and NuOPAL) and with eight replicates. Evaluations were performed weekly since plant emergence. For the vertical distribution, plants were divided into three parts, upper, middle and bottom. The number of eggs present in plants was recorded. A. argillacea and H. virescens eggs were parasitized by Trichogramma pretiosum. There was no preference for oviposition by A. argillacea and H. virescens during the plants phenological stages, as well as T. pretiosum parasitism. Concerning the vertical distribution of eggs, the upper and middle parts of the plants were the most preferred for oviposition by A. argillacea on cultivars NuOPAL, DeltaOPAL and FMX-910, and H. virescens preferred to oviposit in the upper part of the plants. T. pretiosum preferred to oviposit in A. argillacea eggs on the upper and middle parts of the plants, and in H. virescens on the upper part of the plants / Mestre

CAPES; CNPq / Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae) é um inseto originário da Austrália que está causando sérios danos à cultura do eucalipto ao redor do mundo. Ao alimentar-se da seiva das folhas, causa seu bronzeamento, podendo levar à desfolha. Medidas de controle estão sendo estudadas e a mais promissora é o parasitoide de ovos Cleruchoides noackae (Hymenoptera: Mymaridae). Produtos alternativos a base de compostos provenientes de plantas com potencial inseticida também poderiam ser uma ferramenta importante, e talvez serem utilizados concomitantemente com o parasitoide, visando um controle mais efetivo. Desta forma, o objetivo deste trabalho foi verificar a ação dos extratos aquosos de Matricaria chamomilla, Echinodorus grandiflorus, Punica granatum, Maytenus ilicifolia e Origanum majorana a 5% sobre T. peregrinus. Além disso, estudar sua possível toxicidade contra C. noackae e Gallus domesticus L., tendo em vista que estes compostos podem ter efeito negativo indesejado sobre organismos não alvo. Em uma primeira etapa, cromatografia líquida de alta eficiência (HPLC) foi utilizada para verificar os compostos fenólicos presentes nos extratos. Os extratos, então, foram testados sobre percevejo adultos, em confinamento (para verificar a ação inseticida) e teste de livre escolha (para verificar a ação repelente). Os três extratos que mostraram melhores resultados foram selecionados para os testes com os organismos não alvo. Com relação à C. noackae, testes pré e pós-parasitismo, de confinamento e de livre-escolha foram realizados para verificar se os extratos afetariam a escolha do hospedeiro pelas fêmeas ou o desenvolvimento das fases imaturas do parasitoide. Para verificar se os extratos seriam tóxicos a G. domesticus, estes foram adicionados à dieta de aves juvenis por cinco dias. Parâmetros como peso, consumo de alimento, quantificação de enzimas séricas e análise histopatológica foram realizados. Por meio das análises cromatográficas, foram detectados os ácidos gálico, ferúlico, cafeico, cumárico e vanílico. Os extratos levaram à mortalidade de 100% dos insetos em até 49% do tempo, quando comparados com a testemunha, mas E. grandiflorus, Matricaria chamomilla e Maytenus ilicifolia destacaram-se mostrando efeito repelente, sendo selecionados para a próxima etapa. Nenhum destes afetou a escolha do hospedeiro pela fêmea ou a emergência dos parasitoides, quando comparado com a testemunha. Além disso, os extratos não causaram alterações em G. domesticus, em nenhum dos parâmetros avaliados. Desta forma, verificou-se que E. grandiflorus, Matricaria chamomilla e Maytenus ilicifolia têm potencial para serem utilizados no controle de T. peregrinus, bem como mostraram-se seguros para C. noackae e G. domesticus. / Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae ) is an insect from Australia which is causing severe damage to eucalyptus crops around the world. When feeding from the leaves sap, it causes bronzening, and in extreme cases, may lead to the tree death. Control methods have been studied and the most promising so far is the egg parasitoid Cleruchoides noackae (Hymenoptera: Mymaridae). Alternative products from plants with insecticidal properties could also be a viable option, and they might even be used concomitantly with C. noackae, aiming for a most effective control, but still safe for the environment. Thus, the objective of this work was to verify the action of 5% aqueous plant extracts of Matricaria chamomilla, Echinodorus grandiflorus, Punica granatum, Maytenus ilicifolia a n d Origanum majorana on T. peregrinus. In addition, we aimed to study the extracts potential toxicity to C. noackae and Gallus domesticus L., since the plant compounds might have negative effect upon the non-target organisms. At first, HPLC (High Performance Liquid Chromatography) was used to verify which phenolic compounds would be found in the plant extracts. These were tested on bronze bug adults, in confinement test (to verify the insecticidal action of the extracts) and free-choice test (to verify the repellency). The extracts that showed better results were selected for further tests with non-target organisms. Regarding C. noackae, pre-parasitism and post-parasitism, confinement and free-choice tests were performed to verify if the extracts would affect the host-choosing by the female or the development of the immature stages of the parasitoid. To verify if the extracts would be toxic to G. domesticus, the plant extracts were added to young birds feed for five days. Parameters such as weight gain, food intake, quantification of serum enzymes and histopathological analysis were carried out. HPLC analysis detected gallic, ferulic, vanillic, caffeic and cumaric acid in the extracts samples. All plant extracts tested reduced T. peregrinus survival, but E. grandiflorus, Matricaria chamomilla Maytenus ilicifolia had also a repellent effect, and were tested on the non-target organisms. None of these extracts affected neither the host choice by C. noackae nor adult emergency, when compared to the control group. In addition, the extracts did not cause alterations in any of the studied parameters. Thus, we verified that E. grandiflorus, Matricaria chamomilla and Maytenus ilicifolia have potential to be used to control T. peregrinus and are safe to C. noackae and G. domesticus.

CAPES; CNPq / Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae) é um inseto originário da Austrália que está causando sérios danos à cultura do eucalipto ao redor do mundo. Ao alimentar-se da seiva das folhas, causa seu bronzeamento, podendo levar à desfolha. Medidas de controle estão sendo estudadas e a mais promissora é o parasitoide de ovos Cleruchoides noackae (Hymenoptera: Mymaridae). Produtos alternativos a base de compostos provenientes de plantas com potencial inseticida também poderiam ser uma ferramenta importante, e talvez serem utilizados concomitantemente com o parasitoide, visando um controle mais efetivo. Desta forma, o objetivo deste trabalho foi verificar a ação dos extratos aquosos de Matricaria chamomilla, Echinodorus grandiflorus, Punica granatum, Maytenus ilicifolia e Origanum majorana a 5% sobre T. peregrinus. Além disso, estudar sua possível toxicidade contra C. noackae e Gallus domesticus L., tendo em vista que estes compostos podem ter efeito negativo indesejado sobre organismos não alvo. Em uma primeira etapa, cromatografia líquida de alta eficiência (HPLC) foi utilizada para verificar os compostos fenólicos presentes nos extratos. Os extratos, então, foram testados sobre percevejo adultos, em confinamento (para verificar a ação inseticida) e teste de livre escolha (para verificar a ação repelente). Os três extratos que mostraram melhores resultados foram selecionados para os testes com os organismos não alvo. Com relação à C. noackae, testes pré e pós-parasitismo, de confinamento e de livre-escolha foram realizados para verificar se os extratos afetariam a escolha do hospedeiro pelas fêmeas ou o desenvolvimento das fases imaturas do parasitoide. Para verificar se os extratos seriam tóxicos a G. domesticus, estes foram adicionados à dieta de aves juvenis por cinco dias. Parâmetros como peso, consumo de alimento, quantificação de enzimas séricas e análise histopatológica foram realizados. Por meio das análises cromatográficas, foram detectados os ácidos gálico, ferúlico, cafeico, cumárico e vanílico. Os extratos levaram à mortalidade de 100% dos insetos em até 49% do tempo, quando comparados com a testemunha, mas E. grandiflorus, Matricaria chamomilla e Maytenus ilicifolia destacaram-se mostrando efeito repelente, sendo selecionados para a próxima etapa. Nenhum destes afetou a escolha do hospedeiro pela fêmea ou a emergência dos parasitoides, quando comparado com a testemunha. Além disso, os extratos não causaram alterações em G. domesticus, em nenhum dos parâmetros avaliados. Desta forma, verificou-se que E. grandiflorus, Matricaria chamomilla e Maytenus ilicifolia têm potencial para serem utilizados no controle de T. peregrinus, bem como mostraram-se seguros para C. noackae e G. domesticus. / Thaumastocoris peregrinus (Hemiptera: Thaumastocoridae ) is an insect from Australia which is causing severe damage to eucalyptus crops around the world. When feeding from the leaves sap, it causes bronzening, and in extreme cases, may lead to the tree death. Control methods have been studied and the most promising so far is the egg parasitoid Cleruchoides noackae (Hymenoptera: Mymaridae). Alternative products from plants with insecticidal properties could also be a viable option, and they might even be used concomitantly with C. noackae, aiming for a most effective control, but still safe for the environment. Thus, the objective of this work was to verify the action of 5% aqueous plant extracts of Matricaria chamomilla, Echinodorus grandiflorus, Punica granatum, Maytenus ilicifolia a n d Origanum majorana on T. peregrinus. In addition, we aimed to study the extracts potential toxicity to C. noackae and Gallus domesticus L., since the plant compounds might have negative effect upon the non-target organisms. At first, HPLC (High Performance Liquid Chromatography) was used to verify which phenolic compounds would be found in the plant extracts. These were tested on bronze bug adults, in confinement test (to verify the insecticidal action of the extracts) and free-choice test (to verify the repellency). The extracts that showed better results were selected for further tests with non-target organisms. Regarding C. noackae, pre-parasitism and post-parasitism, confinement and free-choice tests were performed to verify if the extracts would affect the host-choosing by the female or the development of the immature stages of the parasitoid. To verify if the extracts would be toxic to G. domesticus, the plant extracts were added to young birds feed for five days. Parameters such as weight gain, food intake, quantification of serum enzymes and histopathological analysis were carried out. HPLC analysis detected gallic, ferulic, vanillic, caffeic and cumaric acid in the extracts samples. All plant extracts tested reduced T. peregrinus survival, but E. grandiflorus, Matricaria chamomilla Maytenus ilicifolia had also a repellent effect, and were tested on the non-target organisms. None of these extracts affected neither the host choice by C. noackae nor adult emergency, when compared to the control group. In addition, the extracts did not cause alterations in any of the studied parameters. Thus, we verified that E. grandiflorus, Matricaria chamomilla and Maytenus ilicifolia have potential to be used to control T. peregrinus and are safe to C. noackae and G. domesticus.

O equilíbrio entre insetos-praga e inimigos naturais existentes na cultura da soja, pode ser influenciado pelo manejo do solo, produtos fitossanitários e cultivares de soja. O presente estudo avaliou a diversidade de lepidópteros associados à cultura da soja, no continente Americano, e a abundância específica destes insetos e seus inimigos naturais (parasitóides e fungos entomopatogênicos), em soja convencional e transgênica RR, com aplicação de herbicidas seletivos (Amplo® e Aramo®) e uma formulação de glifosato (Gliz®), sendo o cultivo da soja BRS 133-convencional e BRS Charrua RR-transgênico realizado em Vacaria, RS, sob manejo de solo convencional, em três lotes de um hectare cada. Nas amostragens semanais, os lepidópteros foram coletados com pano-de-batida, mantidos em criação laboratorial até a obtenção dos adultos, dos parasitóides ou dos fungos entomopatogênicos. Também realizaram-se amostragens de solo para isolamento de fungos entomopatogênicos. Elaborou-se uma listagem dos lepidópteros associados à cultura da soja no continente Americano, relacionando-se 71 espécies cujas formas larvais já foram referidas alimentando-se de soja. No presente estudo foram coletadas 1634 larvas de lepidópteros identificados em 22 táxons, destacando-se Anticarsia gemmatalis, Pseudoplusia includens e Rachiplusia nu como as mais representativas (83,05% das larvas coletadas). A aplicação da formulação de glifosato afetou negativamente o número médio de lagartas em relação aos demais lotes tratados com herbicidas seletivos. Os himenópteros, dípteros e strepsípteros foram responsáveis pelo parasitismo de 34,52% das lagartas. Entretanto com relação ao parasitismo específico, observou-se que entre as lagartas parasitadas, 93,05% pertenciam às três espécies mais freqüentes, destacando-se os plusiíneos que foram mais parasitados que A. gemmatalis. N. rileyi foi o único fungo entomopatogênico isolado a partir de lagartas, sendo responsável por 1,41% da mortalidade das três espécies mais abundantes. Os números de unidades formadoras de colônias de Beauveria, Metarhizium e Paecilomyces, isolados das amostras de solo não diferiram estatisticamente entre os lotes. / In soybean plantations, the equilibrium between insect pests and their natural enemies can be influenced by various factors such as soil management, use of phytosanitary products and soybean cultivar. This study evaluated the diversity of Lepidoptera associated with soybean crops in the Americas, and the specific abundance of these organisms and their natural enemies (parasitoids and entomopathogenic fungi) on conventional and transgenic RR soybean, treated with selective herbicides and glyphosate formulations. The experiment was carried out in Vacaria, Rio Grande do Sul state. Conventional BRS 133 and transgenic RR soy were each planted on three, one-hectare plots and treated with either selective herbicides or a glyphosate formulation. During weekly sampling, Lepidoptera were collected using the drop cloth method and maintained in the laboratory until adults and associated parasitoids and fungi could be obtained. Entomopathogenic fungi were isolated from soil samples. Based on literature data one list of 71 species of Lepidoptera that had been previously reported as feeding on soybean crop was prepared. In the present study, 1634 Lepidoptera larvae were identified in 22 taxa, including the following well-represented species: A. gemmatalis, P. includens e R. nu (83.05% of the larvae collected). The glyphosate treatments reduced the mean number of larvae when compared with the selective herbicide treatments. Hymenopterans, dipterans and strepsipterans were responsible for 34.52% of the total caterpillar parasitism. A large percentage of the larvae parasitized (93.05%) belong to the three most common species of Lepidoptera in our sampling, particularly to the Plusiinae, which were more heavily parasitized than A. gemmatalis. The entomopathogenic fungus N. rileyi was the only species isolated from the caterpillars and was responsible for 1.41% of the deaths amongst the three most common species. The numbers of colony-forming unities of Beauveria, Metarhizium and Paecilomyces, isolated from soil samples, did not differ among the plots.

Varieties of Lantana camara (lantana) have been introduced into many countries of the world as ornamental plants and have become invasive weeds in many countries including South Africa. In South Africa, it mostly invades the sub-tropical eastern and northern range. Mechanical and chemical control options are expensive and ineffective. A biocontrol programme was initiated in South Africa in 1961. To date, 22 insect species, and a fungus have been introduced, of these 10, and the fungus have established. Three indigenous lepidopteran species and an exotic generalist pest mealybug are also associated with the weed. The variable success of some of the agents released on L. camara worldwide has been ascribed to a few factors. One important aspect is the large range of varieties encountered in the field. It is therefore essential to be able to predict the possible establishment and impact of agents on many varieties. Laboratory trials on five of the established agents showed clear varietal preferences. In the field, most of the biocontrol agents had limited geographic ranges, linked to altitudinal conditions, as higher populations were recorded at low lying warm summer rainfall areas. A pink and orange flower corolla lobe and throat colour combination and plants with few to medium leaf hairs were most abundant in South Africa. Most of the agent species had individual preferences towards different flower colour combinations, as the agents built up different population levels on varieties in the field, within the suitable geographic region for the insect species. Eight agents preferred smooth leaved varieties, while three preferred hairy leaves, and three had no specific preference to leaf hairiness. Varietal preferences thus did play a significant role in agent populations and accompanied impact achieved in the field. New candidate agents need to be proven specific under quarantine conditions and the results extrapolated to predict specificity in the field, while avoiding potential non-target effects. Many authors have questioned the validity of laboratory host specificity trials. The conventional wisdom is that insects portray a far wider host range in the laboratory than what they would do in the field. In other words, laboratory studies measure the physiological host range of an agent and are conservative and usually don’t reflect the ecological host range of agents in the field. To avoid unnecessary rejections of biocontrol agents, this study has made a retrospective study of the host specificity of agents established in the field. Their laboratory and field host ranges were compared and it was found that virtually all the agents reflect similar or less non-target effects in the field than predicted during multiple choice trials. Of the 14 agents, only one introduced species, Teleonemia scrupulosa, and the indigenous species, Hypena laceratalis and Aristea onychote were able to sustain populations on non-target species in the field in the absence of L. camara. Insect populations on non-target species were much reduced compared to that on L. camara. Furthermore non-target effects were only recorded on plant species closely related to the target weed. The multiple choice trials therefore predict field non-target effects accurately. Predictions of non-target effects of candidate agents can therefore be accurately predicted by laboratory studies, in terms of species likely to be affected and to what extent. One field that need further study though is the impact of non-target effects, especially on Lippia species by L. camara biocontrol agents.

Aquatic weeds transform and degrade the ecosystems which they invade, impacting various aspects of their surroundings ranging from the community level to disrupting important processes affecting ecosystem services. All of the major aquatic weeds of South Africa are found in the Cape Town Metropolitan Area. Landowners, whether private or public, are legally obliged to manage the listed invasive species through applying environmentally acceptable methodologies. This thesis provides an overview of the strategic management options, prevention, early detection, rapid response and eradication of new invasions, and containment and control species of established species. It discusses the different control methods available for managing aquatic weeds, namely mechanical, manual, chemical and biological, and the integration of different methods to improve their effectiveness. Although various studies have shown that biological control is the most cost–effective, environmentally-friendly and sustainable method, it is not yet fully integrated into weed management programmes in South Africa. In addition, the successes achieved in other parts of the world with the control of water hyacinth through biological control have not been repeated in the urban environment, despite the fact that South Africa has the highest number of biological control agents available for the weed. Urbanisation puts pressure on the natural environment and ecosystem functioning. Nutrient-enriched waters support aquatic weed growth and pose a challenge to the management thereof, in particular with regard to integrating biological control into management programmes. The aims of this study were to determine the reasons for the lack of integration of biological control into weed management programmes in South Africa, to determine the feasibility of integrating biological control in aquatic weed management programmes in a complex urban environmental and socio-political landscape by means of three case studies in the Cape Town Metropolitan Area, which showed that biological control is feasible in urban environments and should be considered. Two surveys were conducted to determine the reasons for the lack of integration of biological control into weed management programmes. The surveys showed that there is a gap between research and implementation as a result of poor communication, non-supporting institutional arrangements and a lack of appropriate capacity and skills at the implementation level. Recommendations were offered to address these issues.

The objectives of this project were to measure changes in frequency of occurrence of submerged macrophytes over the first two growing seasons following stocking with triploid grass carp at two fish per acre and to measure differences in macrophyte biomass between areas excluded from herbivory and adjacent control sites after 16 months following establishment of exclosures. The project also seeks to measure concentrations of fluridone following the herbicide treatment, and to compare two methods of aquatic vegetation sampling.