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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Economic and environmental effects of Integrated Pest Management program: A case study of Hau Giang province (Mekong Delta)

Nguyen, Trung Dung 16 January 2019 (has links)
Since many years, the agro-technical programs such as '3 reduction 3 increase', '1 must 5 reduction' and System of Rice Intensification (SRI) have been carried out with definite results. Recently, IPM program (integrated pest management) – a more comprehensive measure (using all possible techniques and methods to keep the pest populations below a level causing economic injury) – has been firstly piloted on a large scale in the Mekong Delta. This paper presents the main results of piloting IPM program in 2,610 hectares during 2014-2017 in Hau Giang province. As results, farmers have better economic benefit in production; the quality of rice has been gradually improved and can overcome the technical barriers of advanced countries in rice trade such as US, EU and Japan. In addition, the environmental and ecological consequences can be avoided due to overuse of fertilizer and pesticide. Field ecosystems will be gradually restored. / Từ nhiều năm nay những chương trình kỹ thuật nông nghiệp như '3 giảm 3 tăng', '1 phải 5 giảm' và hệ thống canh tác lúa cải tiến (SRI) đã được áp dụng và đã có những kết quả nhất định. Còn chương trình quản lý dịch hại tổng hợp IPM - một biện pháp tổng hợp và tích cực hơn (sử dụng tất cả các kỹ thuật và biện pháp thích hợp có thể được, nhằm duy trì mật độ của các loài gây hại dưới mức gây ra những thiệt hại kinh tế) – được thực nghiệm đầu tiên trên diện rộng ở Đồng bằng sông Cửu Long. Bài báo này trình bày những kết quả chính trong thử nghiệm ở 2.610 ha lúa trong thời gian 2014-2017 ở ở tỉnh Hậu giang. Kết quả là quản lý dịch hại ở ngưỡng cho phép, người nông dân có lợi hơn về kinh tế trong sản xuất, chất lượng gạo từng bước được cải thiện và có khả năng vượt qua các hàng rào kỹ thuật trong thương mại lúa gạo của các nước tiên tiến như USA, châu Âu, Nhật Bản. Ngoài ra tránh được hệ quả về môi trường sinh thái do sử dụng quá mức phân bón hóa học và ô nhiễm do thuốc bảo vệ thực vật và hệ sinh thái đồng ruộng dần được phục hồi.
82

Busca de compostos em Chenopodium spp. (Chenopodiaceae) com bioatividade em relação a pragas de grãos armazenados / Searching for Chenopodium spp. (Chenopodiaceae) compounds with bioactivity against stored grain pests

Tavares, Márcio Aurélio Garcia Correia 18 December 2006 (has links)
Este trabalho foi realizado com o objetivo de avaliar a bioatividade de pós, extratos aquosos e não aquosos (hexano, clorofórmio e metanol) de folhas e frutos de Chenopodium ambrosioides L., Chenopodium quinoa Willd. e Chenopodium album L. sobre as pragas de grãos armazenados, Sitophilus zeamais Mots. e Rhyzopertha dominica (Fabr.), bem como avaliar o potencial inseticida do óleo essencial de C. ambrosioides, e o efeito repelente e inseticida de algumas substâncias (limoneno, α-pineno e p-cimeno) constituintes deste. As plantas de Chenopodium spp. foram cultivadas na área experimental do Departamento de Entomologia, Fitopatologia e Zoologia Agrícola da ESALQ/USP, de maneira a possibilitar a coleta das respectivas estruturas vegetais e posterior obtenção dos pós (através de secagem e moagem) e extratos aquosos (imersão dos pós em água por 24 horas) e não aquosos (maceração com solventes). O óleo essencial de C. ambrosioides foi obtido pelo processo de hidrodestilação. Análises dos constituintes dos óleos essenciais foram feitas por cromatografia gasosa acoplada à espectroscopia de massas (CG/EM). Os insetos utilizados nos ensaios foram obtidos de criação mantida em grãos de trigo. Avaliou-se o efeito dos pós, extratos aquosos e não aquosos de Chenopodium spp., e das substâncias do óleo essencial de C. ambrosioides sobre o comportamento (atratividade e/ou repelência) dos besouros. Avaliou-se também o efeito inseticida dos pós, extratos aquosos e não aquosos de Chenopodium spp., e do óleo essencial de C. ambrosioides e alguns de seus constituintes sobre os insetos. De acordo com os resultados obtidos, concluiu-se que: a) extratos em clorofórmio de frutos de C. ambrosioides e C. quinoa apresentam repelência aos adultos de S. zeamais; b) extrato em clorofórmio de folhas de C. quinoa é atraente aos adultos de S. zeamais; c) pós e extratos de C. album e C. quinoa não apresentam atividade inseticida e nem afetam o desenvolvimento de S. zeamais e R. dominica; d) pós de C. ambrosioides apresentam potencial inseticida e afetam o desenvolvimento de S. zeamais e R. dominica; e) extrato em clorofórmio de frutos de C. ambrosioides apresenta alta atividade inseticida sobre adultos de ambos os besouros testados; f) adultos de S. zeamais são mais suscetíveis a pós de C. ambrosioides quando comparados aos adultos de R. dominica; g) óleo essencial de C. ambrosioides não apresenta atividade inseticida e não afeta o desenvolvimento de S. zeamais e R. dominica; h) limoneno, α-pipeno e p-cimeno não apresentam efeito repelente e tóxico sobre R. dominica; i) limoneno e p-cimeno são repelentes a S. zeamais; j) limoneno, α-pipeno e p-cimeno apresentam baixo efeito tóxico sobre S. zeamais. / This work was carried out to evaluate the bioactivity of powder, aqueous and not aqueous (hexanic, chloroformic and methanolic) extracts of leaves and fruits of Chenopodium ambrosioides L., Chenopodium quinoa Willd. and Chenopodium album L. on the stored grain pests, Sitophilus zeamais Mots. and Rhyzopertha dominica (Fabr.), as well as to evaluate the insecticidal potential of the essential oil of C. ambrosioides and the repellent and insecticidal effects of some substances (limonene, α-inene and p-cimene) constituents of this oil. Plants were cultivated in the experimental area of the \"Departamento de Entomologia, Fitopatologia e Zoologia Agrícola, ESALQ/USP\", to obtain the vegetable structures and the respective powders aqueous extracts (immersion of powders in water for 24 hours) and not aqueous extracts (through maceration with organic solvents). Essential oil from C. ambrosioides plants was obtained by hydrodistilation process. Analysis of the essential oil constituents was done by gas cromatography coupled to mass spectrometry (GC/MS). Insects used in the trials were reared in wheat grains. It was evaluated the effect of the powder, aqueous and not aqueous extracts of Chenopodium spp. and of the constituents of the C. ambrosioides essential oil on the behavior (attractiveness and/or repellence) of the beetles. It was also evaluated the insecticidal effect of the powder, aqueous and not aqueous extracts of Chenopodium spp. and of the essential oil of C. ambrosioides and some of its constituents on the insects. According to the results it is concluded that: a) chloroformic extracts from fruits of C. ambrosioides and C. quinoa present repellence effect to S. zeamais adults; b) chloroformic extracts from leaves of C. quinoa are attractive to S. zeamais adults; c) powders and extracts of C. album and C. quinoa do not present insecticidal activity and do not affect S. zeamais and R. dominica development; d) powders from C. ambrosioides present insecticidal potential and affect the S. zeamais and R. dominica development; e) chloroformic extract from C. ambrosioides fruits presents high insecticidal activity to adults of both beetle; f) adults of S. zeamais are more susceptible to the powders and chloroformic extract of C. ambrosioides when compared to the adults ofR. dominica g) essential oil of C. ambrosioides does not present insecticidal activity and does not affect the S. zeamais and R. dominica development; h) limonene, α-pinene and p-cimene do not present repellent and insecticide effect to R. dominica; i) limonene and p-cimene are repellent to S. zeamais; j) limonene, α-pinene and p-cimene present low toxic effect to S. zeamais.
83

Distribuição espacial, efeito do manejo da palha pós-colheita e da aplicação de Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae) na ocorrência de Sphenophorus levis Vaurie, 1978 (Coleoptera: Curculion / Spatial distribution, effect of post-harvest management of straw and Beauveria bassiana (Balsamo) Vuillemin (Hypocreales: Cordycipitaceae) application in the occurrence of Sphenophorus levis Vaurie, 1978 (Coleoptera: Curculionidae) in sugarcane

Canassa, Fernanda 23 January 2015 (has links)
O Brasil é o maior produtor de cana-de-açúcar (Saccharum officinarum L.) do mundo e a cultura continua em expansão na safra 2014/15. A expansão das áreas de plantio de cana-de-açúcar e o sistema de colheita mecanizada de cana crua tem levado ao aumento proporcional de inúmeras pragas da cultura, destacando-se o bicudo da cana, Sphenophorus levis, considerado praga primária e limitante da cultura. Inicialmente, essa espécie foi considerada restrita a região de Piracicaba, mas desde 2010 foi encontrada nos estados de São Paulo, Minas Gerais, Paraná, Mato Grosso do Sul, Mato Grosso e Goiás. Suas larvas abrem galerias nos rizomas, causando danos diretos nos tecidos dos colmos, sobretudo nas épocas mais secas do ano, o que ocasiona a morte das touceiras, falhas na rebrota, além de promover danos indiretos, como o aumento do número de plantas invasoras que competem com a cultura. Os métodos químico, mecânico, cultural e biológico já foram testados até o momento, no entanto, o sucesso no seu controle ainda não foi obtido e a população dessa praga continua crescendo e se tornando mais constante nos canaviais pelo Brasil. Dessa forma, estudar estratégias para a melhoria do manejo de S. levis é fundamental para o estabelecimento de métodos de controle eficientes no contexto do MIP. Diante disso, objetivou-se com esse trabalho: 1) Determinar a distribuição espacial e a flutuação populacional de S. levis; 2) Testar o manejo da palha pós-colheita nas linhas de plantio na ocorrência de S. levis e; 3) Avaliar a eficácia da aplicação de Beauveria bassiana na população de S. levis. Em relação à flutuação populacional de S. levis foi observada uma elevação linear da última quinzena de outubro para a primeira de novembro, com queda subsequente e, aumento populacional maior à partir da última quinzena de dezembro. O pico populacional se deu no mês de março, seguido por uma rápida redução a partir de abril. A proporção de fêmeas foi similar a de machos em todos os tratamentos. Os dados sugerem que não houve efeito dos tratamentos na distribuição de adultos do bicudo. Os resultados da flutuação populacional, da distribuição de frequência e distribuição espacial se complementam, pois, em hipótese, a distribuição dos adultos está diretamente relacionada com a flutuação populacional, uma vez que em altas densidades a distribuição foi agregada. Além disso, as estratégias de afastamento da palha da linha de plantio não interferiram nos níveis de infestação de S. levis, quando comparado ao tratamento que não houve manejo da palha e, essa tática utilizada conjuntamente à aplicação de B. bassiana também não influenciou na densidade populacional de adultos de S. levis no período avaliado. Diante disso, concluiu-se que a distribuição de S. levis em cana-de-açúcar apresenta o padrão agregado em altas densidades populacionais; o manejo da palha entre as linhas de cana-de-açúcar não reduz a densidade populacional de S. levis em locais com elevado histórico de infestação e, são necessários mais estudos para ajustar a dose de B. bassiana adequada e eficaz no controle de S. levis. / Brazil is the world\'s largest sugarcane producer and the cultivated area continues to expand in 2014/2015 season. This expansion, along with the mechanical harvesting of green sugarcane leads to a proportional increase in the number of crop pests, especially the sugarcane weevil, Sphenophorus levis, considered a primary and limiting pest in this crop. Initially, this species was restricted to the Piracicaba region, however, since 2010 it has been found in several regions of São Paulo State, and also in other states in the country, such as Minas Gerais, Paraná, Mato Grosso do Sul, Mato Grosso and Goiás. The larvae penetrate the basal part of the plants and the rhizomes, building irregular galleries and causing damage to stem tissues, mainly in the driest season, leading to the death of clumps, failures in regrowth and, consequently, indirect damage due to the increase in the incidence of invasive plants that compete with the crop. Chemical, mechanical, cultural and biological methods have already been tested, however, the success in pest control has not yet been achieved and the population of S. levis continues to grow, becoming more constant in Brazilian sugarcane fields. Thus, the study of strategies to enhance the management of S. levis is essential to adopt effective control methods in the IPM framework. In this sense, this study aims to: 1) Determine the spatial distribution and population dynamics of S. levis; 2) Evaluate the postharvest management of straw on planting rows in occurrence of S. levis and; 3) Evaluate the efficacy of B. bassiana application in the S. levis population in sugarcane. Concerning population dynamics of S. levis, it was observed a linear increase beginning in the last quarter of October until November, with a subsequent decrease and, a highest population increase was observed in the last half of December. The population peak occurred in March, followed by a fast decline in early April. The proportion of females to males was similar in all treatments. The data suggest that there was no effect of treatments on the distribution of adult weevils. The results of population dynamics, frequency distribution and spatial distribution are complementary, because, hypothetically, the distribution of adults is directly related to population dynamics, since at high densities the distribution was aggregated. In addition, strategies for straw management in the planting row did not affect the infestation levels of S. levis and this procedure along with the addition of B. bassiana did not influence population density of adults during the study period. Hence, it is concluded that the distribution of S. levis in sugarcane exhibits an aggregated pattern at high population densities. Straw management between the cane rows does not reduce population density of S. levis in areas with high historical infestation. Therefore, further studies are needed to adjust the appropriate and effective concentration of B. bassiana in the control of S. levis.
84

Toxicidade de agroquímicos recomendados para a produção integrada de citros sobre o ácaro predador Euseius concordis (Chant) (Acari: Phytoseiidae) / Toxicity of agrochemicals recommended for citrus integrated production on predator mite Euseius concordis chant (Acari: Phytoseiidae)

Franco, Aline Aparecida 20 January 2017 (has links)
As plantas cítricas brasileiras são acometidas por inúmeros artrópodes praga e agentes fitopatógenos causadores de doenças, que exigem pulverizações frequentes de agroquímicos para reduzir as perdas econômicas ocasionada por eles. No entando, esse intenso uso de compostos químicos podem ocasionar desiquilíbrios no agroecossistema, como a mortalidade de agentes de controle biológico. Neste sentido, objetivou-se com esse estudo avaliar os efeitos letal e subletais de inseticidas, acaricidas e fungicidas recomendados para a produção integrada de citros sobre o ácaro predador Euseius concordis (Chant) (Acari: Phytoseiidae) em condições de laboratório, além de estudar as interferências transgeracionais destes agroquímicos em aspectos de desenvolvimento e reprodução, estimando os parâmetros de tabela de vida da progênie das fêmeas de E. concordis que mantiveram contato residual, avaliando também a duração do efeito nocivo dos agroquímicos sobre adultos de E. concordis em condições de semi-campo, e para ter resultados mais completos, avaliou a capacidade de predação do E. concordis sobre formas jovens de Panonychus citri (McGregor) (Acari: Tetranychidae) em condições laboratoriais o que subsidiou os estudos de interferência de agroquímicos sobre a capacidade de predação de E. concordis. Os resultados demonstraram que ~ 73% dos inseticidas avaliados foram considerados moderadamente nocivos à nocivos à espécie em estudo, além disso, muitos dos inseticidas estudados tiveram interferência negativa nos parâmetros de tabela de vida da progênie (efeito transgeracional), e outros, como o imidacloprido, tiametoxam e lambda-cialotrina elevaram significativamente a taxa líquida de reprodução (Ro), taxa intrínseca de crescimento (rm) e razão finita de aumento (?), podendo indicar um possível efeito de hormese desses inseticidas à população de E. concordis. Já nos bioensaios com acaricidas, verificou que 50% dos avaliados foram considerados nocivos, causando altas mortalidades às fêmeas do ácaro estudado, destacando nesse grupo de agroquímicos o efeito trangeracional do acaricida etoxazol, que foi considerado inócuo a fêmeas adultas de E. concordis, no entanto, a progênie destas fêmeas teve mortalidade de 100% no estágio larval. Dos fungicidas avaliados, aproximadamente 70% foram considerados inócuos ou levemente nocivos às fêmeas de E. concordis (classe 1 e 2, segundo IOBC/ WPRS), sendo o grupo de agroquímicos menos nocivos ao ácaro em estudo. No presente trabalho, os resultados indicaram que, mesmo os agroquímicos considerados pouco nocivos ao ácaro predador E. concordis podem alterar o comportamento de busca e predação, como foi observado para as fêmeas que mantiveram contato residual com o fungicida tebuconazol e os inseticidas piriproxifem e tebufenozida, que reduziram significativamente a predação às ninfas de P. citri. Para tanto, esse estudo oferece informações que podem ser utilizadas em programas de manejo integrado de pragas, que preconize aliar controle químico com o biológico, com próposito de reduzir o uso de pesticida para controle de ácaros-praga, baseado na conservação do ácaro E. concordis nos pomares, além de fornecer informações pertinentes para estudos dessa natureza, direcionando para que os estudos de toxicidade sejam mais completos, baseando-se também nos efeitos transgeracionais e comportamentais que um pesticida pode causar a uma população de inimigos naturais. / Brazilian citriculture are affected by numerous pest arthropods and phytopathogenic agents causing diseases that require frequent sprays of agrochemicals to reduce the economic losses caused by them. However, the intensive use of chemicals compounds can cause imbalances in the agroecosystem, like the mortality of biological control agents, for instance. In this sense, this study aimed to evaluate the lethal and sublethal effects of insecticides, acaricides and fungicides recommended for the integrated production of citrus on the predatory mite Euseius concordis (Chant) (Acari: Phytoseiidae) under laboratory conditions, in addition to studying the transgenerational interference of these agrochemicals in aspects of development and reproduction, estimating the life table parameters of the progeny of E. concordis females who kept contactwith the residues, also evaluating the duration of the harmful effects of agrochemicals on adult E. concordis in semi-field, and have more complete results, evaluated the capacity predation of E. concordis on young stages of Panonychus citri (McGregor) (Acari: Tetranychidae) in laboratory conditions, that supported pesticide interference studies on the predation of E. concordis. The results showed that ~ 73% of the insecticides were moderately harmful to harmful, concerning the studied species, and that many of the agrochemicals studied have negative interference in the life table parameters of progeny (transgenerational effect). Others, such as imidacloprid, thiamethoxam and lambda-cyhalothrin significantly increased the net reproductive rate (Ro), intrinsic rate of increase (rm) and finite rate of increase (λ), which may indicate a possible hormesis effect of these insecticides to the population of E. concordis. But, in cases of the bioassays with acaricides, it was found that 50% of the evaluated ones were considered harmful, causing high mortality to the female of this mite, highlighting in this group of agrochemicals the trangeracional effect of etoxazole, which was considered harmless to adult females of E. concordis, however, the offspring of these females had 100% of mortality in the larval stage. From the fungicides evaluated, approximately 70% were considered harmless or slightly harmful to E. concordis females (class 1 and 2, according IOBC / WPRS), being, these ones, the less harmful agrochemicals group to mite study. This study also assessed that even agrochemicals considered less harmful to predatory mite E. concordis can change the search and predation behavior, as observed for females who have maintained residual contact with fungicides tebuconazole and insecticides pyriproxyfen and tebufenozide, which significantly reduced predation of P. citri nymphs. Therefore, this study provides information that can be used in integrated pest management programs, which would include combining chemical with biological control, with the porpose of reducing the use of pesticide to control pest mites, based on the conservation of E. concordis in the groves, as well as providing relevant information for such studies, directing that the toxicity studies are more complete, also based on transgenerational and behavioral effects that a pesticide can cause in a population of natural enemies.
85

A regional view of an impending invasion: western corn rootworm development in Northern Germany

Wilstermann, Anne 31 May 2012 (has links)
No description available.
86

Commercial Bumble Bees as Vectors of the Microbial Antagonist Clonostachys rosea for Management of Botrytis Blight in Wild Blueberry (Vaccinium angustifolium)

Reeh, Kevin 10 May 2012 (has links)
Greenhouse and laboratory experiments in 2011 determined that Clonostachys rosea can effectively prevent Botrytis cinerea infection in Vaccinium angustifolium blossoms. In vitro testing demonstrated that C. rosea germination was not significantly affected by the presence of Switch®, but was by either Pristine® or Maestro®. Field experiments completed during the summer of 2010 and 2011 indicated that the dispenser designs tested had no significant effects on Bombus impatiens foraging behaviours, aside from hive-activity. There was also no difference in the quantity of C. rosea applied by each to bees, the distribution of product in the field, or for blossoms exposed to bees from each dispenser to resist infection by B. cinerea. However, B. cinerea prevalence in blossoms from both treatments was significantly different from the control, with infection reduced by 10-20%. Technical issues with dispensers currently appear to be the limiting factor for application within commercial wild blueberry production.
87

NOSEMA CERANAE IN WESTERN HONEY BEES (APIS MELLIFERA): BIOLOGY AND MANAGEMENT

Williams, Geoffrey Rhys 27 March 2013 (has links)
Western honey bees (Apis mellifera; hereafter honey bees) provide vital pollination services to global agriculture and biodiversity. However in recent years they have experienced severe population declines in many regions of the northern hemisphere. Although causes of these honey bee declines are not well understood, multiple pressures such as changes in land-use and climate, management issues, and introduced parasites are believed to be responsible. First described in honey bees in 2006 during a period of high colony mortalities, the microsporidian gut parasite Nosema ceranae became of great concern. In this dissertation I investigated the distribution, management, virulence, and inter-specific interactions of this introduced species. First, I described and clarified the multiple pressures believed to influence honey bee health, including N. ceranae, especially in relation to the mysterious phenomenon Colony Collapse Disorder. I then surveyed colonies in Maritime Canada for N. ceranae and the historic honey bee microsporidian Nosema apis. Although both species were present at a regional scale, intensive sampling in Nova Scotia revealed that N. ceranae was highly prevalent compared to the historic congener. Next, I investigated two potential management options for the parasite. Chemotherapy using the fungicide fumagillin reduced N. ceranae spore intensity but had no effect on colony survival, and indoor over-wintering did not reduce spore intensity but was associated with increased colony survivorship in spring. Using a comparative approach, I observed that N. ceranae infection significantly reduced honey bee longevity in the laboratory but did not influence overall colony health or strength in the field. Last, a laboratory study demonstrated reduced spore production during N. ceranae and N. apis co-infection, possibly due to inter-specific competition that has resulted in the displacement of the historic Nosema species by N. ceranae in many global regions. This dissertation provides crucial information on biology and management of N. ceranae that can be used towards the development of an integrated pest management strategy, and for future studies investigating factors that may influence the parasite’s distribution, virulence, and inter-specific interactions.
88

The efficacy of reintroducing the New Zealand falcon into the vineyards of Marlborough for pest control and falcon conservation

Kross, Sara Mae January 2012 (has links)
In our ever more populated world, the rapid expansion and intensification of agriculture is driving worldwide biodiversity loss, and the interactions between production landscapes and wildlife conservation are becoming increasingly important. Farming systems depend on ecosystem services such as biological control, while conservationists are calling for the establishment of conservation initiatives in non-preserve landscapes. Despite this, the goals of agriculture and the goals of predator-conservation are rarely mutual. Here, I demonstrate one of the first examples of a mutually beneficial scenario between agriculture and predator conservation. I used, as a case study, a reintroduction project that translocated individuals of the threatened New Zealand falcon (Falco novaeseelandiae) from the hills of Marlborough into vineyards, to determine if predators can survive within an agricultural landscape while simultaneously providing that landscape with biological control services. Examples of vertebrates providing biological control to agriculture are rare. I show that the presence of falcons in vineyards caused an economically important reduction in grape damage worth over US $230/ ha. Falcon presence caused a 78- 83% reduction in the number of introduced European pest birds, which resulted in a 95% reduction in the damage caused by these species. Falcon presence did not cause a reduction in the abundance of the native silvereye (Zosterops lateralis), but did halve the damage caused by this species. To assess the conservation value of the falcon translocations, I used remote videography, direct observations and prey analysis to measure the behavioural changes associated with the relocation of falcons from their natural habitat in the hills and into vineyards. Falcons in vineyard nests had higher nest attendance, higher brooding rates, and higher feeding rates than falcons in hill nests. Additionally, parents in vineyard nests fed their chicks a greater amount of total prey and larger prey items compared to parents in hill nests. I also found an absence of any significant diet differences between falcons in hill and vineyard habitats, suggesting that the latter may be a suitable alternative habitat for falcons. Because reintroduced juvenile falcons were released in areas devoid of adult falcons, it was possible that they were missing essential training normally provided by their parents. I used direct observations to demonstrate that the presence of siblings had similar effects to the presence of parents on the development of juvenile behaviour, with individuals flying, hunting, and playing more often when conspecifics were present. Finally, through the use of artificial nests and remote videography, I identified that falcons nesting in vineyards are likely to suffer lower predation rates. I also found that falcons in vineyards are predated by a less dangerous suite of animals (such as hedgehogs, Erinaceus europaeus, and avian predators), than their counterparts in the hills, which are predated by more voracious species (such as stoats, Mustela erminea, and feral cats, Felis catus). The work presented in this thesis has also added to the current knowledge of New Zealand falcon breeding behaviour, prey preferences, and behavioural development. Although agricultural regions globally are rarely associated with raptor conservation, and the ability of raptors to control the pests of agricultural crops has not been previously quantified, these results suggest that translocating New Zealand falcons into vineyards has potential for both the conservation of this species, and for providing biological control services to agriculture
89

Implementation of the push-pull strategy for Eldana saccharina control on sugarcane in KwaZulu-Natal, South Africa / J.J. Cockburn

Cockburn, Jessica Jane January 2013 (has links)
The aim of the research presented in this dissertation was to further the implementation of push-pull for control of Eldana saccharina on sugarcane in the Midlands North region, KwaZulu-Natal, South Africa. Eldana saccharina, an indigenous stem borer, is the most damaging pest of sugarcane in South Africa, and sustainable control has still not been achieved. The push-pull strategy, a form of habitat management, has been developed for E. saccharina and is recommended as part of an integrated pest management (IPM) approach. Implementation of this strategy for both large- and small-scale farmers was facilitated through mixed methods social research. It included a novel exploratory network analysis to understand the process of technology adoption by farmers. Surveys showed that large-scale farmers have a good knowledge of E. saccharina, IPM and push-pull but that they needed more practical knowledge for implementation of the strategy. Farmers recommended experiential learning opportunities such as field days and model farms to get to know more about this technology. Despite demonstrating a positive attitude towards push-pull, farmers perceived it to be a ‘hassle’ and this is potentially the biggest barrier to its adoption. However, with suitable learning opportunities for farmers and good support for planting inputs, implementation of push-pull is likely to succeed. Sugarcane was shown to play an important role in the livelihoods and farming systems of small-scale growers. They did not perceive E. saccharina as a serious production constraint and had poor knowledge of the pest and its control. Extension for small-scale growers in this region should focus primarily on weed management and on reducing input costs, but still raising awareness of the increasing threat of E. saccharina. On-farm push-pull field trials showed a significant reduction of E. saccharina damage on two farms. Mean percentage damaged internodes decreased from 4.1% to 2.7% and from 1.7% to 1.1% in the presence of the repellent grass species, Melinis minutiflora. Where farmers did not manage their crops well, push-pull was not effective. It is therefore crucial that push-pull within an IPM framework be implemented together with good crop management practices. Stem borer surveys in wetlands on sugarcane farms revealed a high diversity of indigenous stem borers and parasitoids, including a stem borer species, Pirateolea piscator, which may pose a threat to crops in the future. These findings, together with a literature review on the significance of on-farm biodiversity and ecosystem services, demonstrated the value which wetlands have for pest management on sugarcane farms. Wetland health assessments were used to develop a tool for farmers to assess and utilise the wetlands on their farms for improved management of E. saccharina. This study highlights the importance of a farmer-participatory approach to implementation of knowledge-intensive farming practices such as push-pull. The importance of wetlands for providing pest regulatory services on sugarcane farms has shown that environmental sustainability needs to become a fundamental principle of farming and agricultural research. Participatory implementation of push-pull, as recommended in this dissertation, could act as a driving force for agroecology in the South African sugar industry and move sustainable farming practices off the pages of journals and manuals onto farmers’ fields. / Thesis (MSc (Zoology))--North-West University, Potchefstroom Campus, 2013
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Implementation of the push-pull strategy for Eldana saccharina control on sugarcane in KwaZulu-Natal, South Africa / J.J. Cockburn

Cockburn, Jessica Jane January 2013 (has links)
The aim of the research presented in this dissertation was to further the implementation of push-pull for control of Eldana saccharina on sugarcane in the Midlands North region, KwaZulu-Natal, South Africa. Eldana saccharina, an indigenous stem borer, is the most damaging pest of sugarcane in South Africa, and sustainable control has still not been achieved. The push-pull strategy, a form of habitat management, has been developed for E. saccharina and is recommended as part of an integrated pest management (IPM) approach. Implementation of this strategy for both large- and small-scale farmers was facilitated through mixed methods social research. It included a novel exploratory network analysis to understand the process of technology adoption by farmers. Surveys showed that large-scale farmers have a good knowledge of E. saccharina, IPM and push-pull but that they needed more practical knowledge for implementation of the strategy. Farmers recommended experiential learning opportunities such as field days and model farms to get to know more about this technology. Despite demonstrating a positive attitude towards push-pull, farmers perceived it to be a ‘hassle’ and this is potentially the biggest barrier to its adoption. However, with suitable learning opportunities for farmers and good support for planting inputs, implementation of push-pull is likely to succeed. Sugarcane was shown to play an important role in the livelihoods and farming systems of small-scale growers. They did not perceive E. saccharina as a serious production constraint and had poor knowledge of the pest and its control. Extension for small-scale growers in this region should focus primarily on weed management and on reducing input costs, but still raising awareness of the increasing threat of E. saccharina. On-farm push-pull field trials showed a significant reduction of E. saccharina damage on two farms. Mean percentage damaged internodes decreased from 4.1% to 2.7% and from 1.7% to 1.1% in the presence of the repellent grass species, Melinis minutiflora. Where farmers did not manage their crops well, push-pull was not effective. It is therefore crucial that push-pull within an IPM framework be implemented together with good crop management practices. Stem borer surveys in wetlands on sugarcane farms revealed a high diversity of indigenous stem borers and parasitoids, including a stem borer species, Pirateolea piscator, which may pose a threat to crops in the future. These findings, together with a literature review on the significance of on-farm biodiversity and ecosystem services, demonstrated the value which wetlands have for pest management on sugarcane farms. Wetland health assessments were used to develop a tool for farmers to assess and utilise the wetlands on their farms for improved management of E. saccharina. This study highlights the importance of a farmer-participatory approach to implementation of knowledge-intensive farming practices such as push-pull. The importance of wetlands for providing pest regulatory services on sugarcane farms has shown that environmental sustainability needs to become a fundamental principle of farming and agricultural research. Participatory implementation of push-pull, as recommended in this dissertation, could act as a driving force for agroecology in the South African sugar industry and move sustainable farming practices off the pages of journals and manuals onto farmers’ fields. / Thesis (MSc (Zoology))--North-West University, Potchefstroom Campus, 2013

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