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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.
71

Host selection behavior of the adult parasitoid Microctonus hyperodae Loan (Hymenoptera:Braconidae:Euphorinae) and the egg parasitoid Anaphes victus Huber (Hymenoptera:Mymaridae), parasitoids of the carrot weevil, Listronotus oregonensis LeConte (Coleoptera:Curculionidae)

Cournoyer, Michel, 1976- January 2003 (has links)
The carrot weevil, Listronotus oregonensis LeConte (Coleoptera: Curculionidae), is an important pest of carrot in northeastern North America. The objective of this study was to determine the host selection stimuli used by two L. oregonensis parasitoids: the adult parasitoid Microctonus hyperodae Loan and the egg parasitoid Anaphes victus Huber. / In the first chapter, the response of M. hyperodae females to various odor components from potential hosts and host plants was tested with a Y-olfactometer. / In the second chapter, the effect of L. oregonensis adult sex, feces and movement on host selection behavior of M. hyperodae females was evaluated by quantifying L. oregonensis adult movement and various M. hyperodae female behaviors in an arena. / In the third chapter, the response of A. victus females to different L. oregonensis related odor components was evaluated using a filter paper of which half was moistened with odor components and the other half with water.
72

Mathematical models for the population dynamics and management of the carrot weevil, Listronotus oregonensis (LeConte) (Coleoptera:Curculionidae)

Zhao, Dingxin January 1990 (has links)
The time-varying survival rates of the carrot weevil, Listronotus oregonensis, were estimated by a new method. This method precluded the possibility of negative simulation survival rates. Analysis of carrot weevil population dynamics indicated that the egg mortality was density dependent with Anaphes sordidatus, an egg parasitoid, as a major density dependent factor. Larval mortality was less density dependent. Based on the mortality information, a simulation model for carrot weevil population dynamics was established. The simulation precision, evaluated by comparing simulated and observed egg and larval population dynamics, was satisfactory. Sensitivity analysis indicated that A. sordidatus had a large influence on carrot weevil population dynamics. The economic threshold for carrot weevil control in early carrots was 5 eggs/100 carrots at the peak population density. It ranged from 3.8 to 5.3 eggs/100 carrots in mid-season carrots depending on the selling price. A decision model showed that the best sowing date was after June 5 when risks were not considered. For risk aversion growers, sowing carrots between May 20 and May 31 was the best choice.
73

Volatile profiles for disease detection in stored carrots and potatoes

Ouellette, Eric January 1988 (has links)
No description available.
74

Effects of irrigation rate on the growth, yield, nutritive value, and water use efficiency of Carrot (Daucus carota) and Broccoli (Brasiola oleracea)

Ludong, Daniel Peter M. January 2008 (has links)
The effects of differential irrigation treatments on the water use of broccoli (c.v. Indurance) and carrots (c.v. Stefano) were studied in the rainy, winter season from July to September 2006 and in the dry, summer period from November 2006 to March 2007, respectively. Broccoli and carrots are produced on the Swan Coastal Plain region on Grey Phase Karrakatta Sand. Such soils generally have water holding capacities as low as 10 to 13%. This soil is typical to the Swan Coastal Plain and requires irrigation to be applied at rates of up to 150% of class A pan evaporation (Epan) to optimise growth and quality. / High spatial uniformity (an average of 90%) of water distribution (DU) was achieved with the sprinkler irrigation system. The average irrigation water use efficiencies (Eu) in both the experiments were relatively high, at 78% and 95% in broccoli and carrot trials, respectively. The numerous rainy days during the winter season affected the results of water application efficiencies (Ea) of the broccoli experiment, which ranged from 35% to 43%. This contrasted with the carrot experiment where the water application efficiencies (Ea) of the 100% Epan and Crop Factor (CF) treatments were 81% and 78%, respectively. For the carrot experiment the water application efficiencies for the 100% Epan and crop factor treatments were 14% higher than the 150% Epan treatment. These results indicate that the sprinkler irrigation systems in both experiments showed good performance makes the system suitable for experimental purposes and also for vegetable production on soils of this nature. / Despite the differences in irrigation volume, soil water contents remained very high and did not differ among treatments in both the experiments. The differential soil water stress index (DSWSI) for the 100% Epan (T1) and variable water replacement (VR) (TVR) treatments ranged from 0.74 to 1.71 for both broccoli and carrot trials. There were only small soil water tension differences among all the irrigation treatments and ranged from -2.4 kPa to -7.6 kPa, which was within the range between saturation and field capacity for sandy soil (0 to -10 kPa). / In the broccoli experiment, even though the 150% Epan (T2) irrigation treatment received 46% and 61% more irrigation than the 100% Epan (T1) and variable water replacement (TVR) irrigation treatments respectively, the treatments appeared to be largely negated by the high incidence of rainfall during the growing season. For example, the total depth of water application at 150% Epan was 13.9% and 17.2% greater than 100% Epan and TVR treatments respectively. As such the yield, biomass components and nutritional value (ascorbic acid and carotenoid content) did not vary among the treatments. However, irrigation was still required based on the set scheduling parameters and when considered in isolation of rainfall the irrigation crop water use efficiency (WUEi) on T1 and TVR treatments increased by 1.6-fold compared to T2 treatment. / For the carrot experiment the total depth of water application (rainfall and irrigation) for the 150% Epan treatment was 33% and 23% greater than at 100% Epan and Crop factor (CF) treatments, respectively. The yield (carrot roots) on a fresh weight basis (FW) for plants irrigated with the 150% of Epan and Crop factor (CF) treatments were 16% and 20% higher than the yield for plants irrigated with the 100% Epan treatment. Total (root and shoot) fresh weight of carrot plants irrigated For the carrot experiment the total depth of water application (rainfall and irrigation) for the 150% Epan treatment was 33% and 23% greater than at 100% Epan and Crop factor (CF) treatments, respectively. The yield (carrot roots) on a fresh weight basis (FW) for plants irrigated with the 150% of Epan and Crop factor (CF) treatments were 16% and 20% higher than the yield for plants irrigated with the 100% Epan treatment. Total (root and shoot) fresh weight of carrot plants irrigated with the CF treatment was 17% higher than the total fresh weight of plants irrigated with the 100% Epan treatment. However, there were no significant differences between irrigation treatments for root and total (root and shoot) mass on a dry weight basis and the ratio of carrot root to shoot, on a fresh and dry weight basis. The root lengths for plants grown with the CF and 150% Epan irrigation treatments averaged 30 cm, and were 14% larger than the root lengths for the 100% Epan treatment. The plant height for plants grown with the CF irrigation treatment was 6% higher than at the 100% Epan irrigation treatment and leaf length at the CF irrigation treatment was 12% greater than at the 150% Epan irrigation treatment. The root diameter and leaf width of carrots were not significantly different for all treatments. There were no significant differences in ascorbic acid and total carotenoid content of carrot roots among the three irrigation treatments. The average values of antioxidant content from diphenylpicrylhydrazyl (DPPH) scavenging, ARP (anti radical power) and total trolox equivalent antioxidant capacity were 44.83%, 0.8789 and 1.056μmol TE/g, respectively. The reduction of the irrigation level treatment from the 150% Epan water replacement to the 100% Epan water replacement increased the percentage of the DPPH scavenging by 1.55%, and total antioxidant capacity (AOC) and ARP activities by 4.19%. / On a dry weight basis, the crop water use efficiencies (WUE) (irrigation plus rain water) of carrot plants irrigated with the 100% Epan and CF treatments, were the same (0.013 g/mm). However, these were 30% greater than the WUE values of carrots irrigated with the 150% Epan treatment. On a fresh weight basis, the WUE of carrot plants irrigated with the 100% Epan and CF (0.120 and 0.132 g/mm) treatments were 14% and 26% greater than the WUE of carrot plants irrigated with the 150% Epan treatment, respectively. / An example of the diurnal trends of the carrot’s physiological responses to the irrigation treatments showed that on average, the rate of photosynthesis, stomatal conductance and intercellular CO2 for carrot plants grown with the 150% Epan treatment was higher than the rate of photosynthesis, stomatal conductance and intercellular CO2 at both the 100% Epan and CF treatments. However, not all the physiology measurements showed a significant difference among all the treatments. The variation in the physiological measurements was predominantly influenced by the change of temperature during the diurnal hours. / This study has proven the hypothesis that, on a free draining sandy soil, the irrigation treatments did not affect the growth and yield. However, there was a potential to reduce irrigation volumes from standard industry levels to maximise the WUE without decreasing the yield and crop quality, especially for broccoli and carrot, in Western Australia.
75

Rendimento, qualidade e conservação pós-colheita de cenoura (Daucus carota L.), sob cultivo biodinâmico, em função dos ritmos lunares

Jovchelevich, Pedro [UNESP] 20 June 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-06-20Bitstream added on 2014-06-13T20:54:55Z : No. of bitstreams: 1 jovchelevich_p_me_botfca.pdf: 499030 bytes, checksum: 7f5a990de9b5784be9e42359b9f390f9 (MD5) / Associacao Biodinamica / O presente trabalho teve como objetivo avaliar a influência dos diversos ritmos da Lua (sinódico, sideral, anomalístico, tropical e draconiano) sobre o rendimento, a qualidade e a conservação pós-colheita de cenoura, quando semeada em diferentes datas, sob as mesmas condições de manejo, em uma propriedade familiar com manejo biodinâmico no município de Botucatu-SP. O delineamento experimental utilizado foi o de blocos ao acaso com 31 tratamentos em 2005, e 14 tratamentos em 2006. A diferença entre tratamentos foi a data de semeadura, que variou de 5 de maio a 4 de junho em 2005, e de 25 de abril a 25 de maio em 2006, sempre entre 13 e 15hs. A colheita foi feita 82 dias depois de cada semeadura, equivalente a três ciclos da lua sideral, e no ponto que o consumidor de produtos orgânicos e biodinâmicos valoriza, segundo experiência do produtor. Para retirar o efeito da tendência dos dados na avaliação dos tratamentos, foi utilizada a metodologia de avaliação estatística do cálculo do Índice Estacional (IE). Foram avaliadas as seguintes características: massa fresca de raízes e folhas, massa seca, diâmetro, comprimento, teor de nitrogênio, fósforo e boro das raízes e perecibilidade das raízes com 30, 60 e 90 dias póscolheita. Nos dois períodos avaliados, a massa seca de raízes foi a única que, no contraste entre médias, apresentou diferença significativa nos ritmos sinódico tradicional e sinódico caboclo. No ritmo sinódico tradicional, a fase nova foi superior às fases crescente e cheia. No sinódico caboclo, a fase cheia foi inferior às demais. No contraste entre médias, o ritmo sinódico foi o que mais apresentou resultados significativos, e em menor proporção, os ritmos anomalístico, draconiano e sideral; O ritmo tropical (ascendente X descendente) e teor de nitrogênio não apresentaram resultados significativos... / The purpose of this work was to evaluate the influence of moon rhythms (synodic, sidereal, anomalistic, tropical and draconic) on yield, quality and postharvest storage of Daucus carota L. roots under biodynamic management sowed in different dates. The experiment was carried out over a two period on a biodynamic farm, in Botucatu, São Paulo State, Brazil. Rhythms were tested observing the effects of seeding at different planting dates. The experiment was performed with four randomized blocks and 31 treatments (different dates) in 2005 and fourteen treatments in 2006. The harvest occurred 82 days after the sowing, when carrot roots show the most desirable aspect for the organic and biodynamic consumers. The magnitudes of effects associated with planting at a specific lunar position were measured by the deviations from the trend curve. The following characteristics were evaluated: fresh mass of roots and leaves, dry mass, diameter, length, nitrogen, phosphorus and boron content of the roots and perishability of the roots at 30, 60 and 90 days post-harvest. Dry mass was the only one that in the contrast between averages showed significant results in the two periods of the experiment. Result was that the synodic new phase was superior to the first quarter, and full phases and in the caboclo synodic rhythm, the full phase was inferior to the other. It was clear that the synodic caboclo rhythm had the most significant influence followed by the traditional synodic one. The draconic, sideral and anomalistic had less influence and the tropical rhythm had no influence at all considering studied aspects. Nitrogen and tropical rhythm did not present any lunar influence. The two evaluated periods are still not conclusive related... (Complete abstract click electronic access below)
76

Apiáceas e alternarioses: tratamento de sementes, qualidade fisiológica e sanitária no armazenamento / Apiáceas and alternarioses: seeds treatment, physiological and health quality in storage

Pedroso, Daniele Cardoso 29 February 2012 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / Carrots, cilantro and parsley are vegetable, Apiaceae family, important in agriculture and Brazilian culinary. In recent years, the increasing production of these species led to the emergence of pest problems, especially diseases caused by fungi. In order to minimize the harmful effect of these fungi, the present study was to evaluate the effect of chemical and biological treatment, with or without polymer, in carrot coriander and parsley seeds, contaminated with A. alternata and A. radicina during storage. Were used seeds of carrot, coriander and parsley from producers in Rio Grande do Sul, without any chemical treatment, produced in 2009/2010. After receipt, the seeds were submitted to the initial assessment of water content, germination and health. According with the results of sanity test, in which was detected the presence of Alternaria alternata and A. radicina associated with seeds, were selected seeds of each species, according to the highest percentage of pathogens incidence. After, the seeds were submitted to treatment, according to manufacturers' recommendations, with fungicide Captan® (in dose of 0,002 g.kg-1) or with the biological product based on of Trichoderma spp., Agrotrich plus® (in dose of 25g.ha-1), both added or not polymer Collorseed - Rigran® (in dose of 50 mL. kg-1). Thus, the treatments were: control, seeds + Captan®, seed + Captan® + polymer, seeds + Agrotrich plus®, seeds + Agrotrich plus® + polymer. Quality assessments were performed every three months, the course of a year of storage. Physiological quality was evaluated by germination test, first count germination, cold test, seedling length, emergence and emergence rate index and the health quality through the Blotter test. The seeds treatment of carrot, coriander and parsley, contaminated with A. alternata and A. radicina with the fungicide Captan® + polymer favored the physiological and sanitary quality during storage. The Agrotrich plus®, polymer or not, did not show effectiveness in the treatment of the seed during storage. Additionally, the incidence of A. alternata and A. radicina reduced over twelve months of storage, regardless of the treatment applied to the apiaceas seed. / Cenoura, coentro e salsa são hortaliças, da família Apiaceae, importantes na agricultura e na culinária brasileira. Nos últimos anos, a crescente produção de sementes dessas espécies ocasionou o surgimento de problemas fitossanitários, principalmente doenças causadas por fungos. No intuito de minimizar o efeito nocivo desses fungos, a presente pesquisa teve como objetivo avaliar o efeito do tratamento químico e biológico, associados ou não a polímero, em sementes de cenoura, coentro e salsa, contaminadas com A. alternata e A. radicina durante o armazenamento. Foram utilizadas sementes de cenoura, coentro e salsa provenientes de empresas produtoras do Rio Grande do Sul, sem qualquer tipo de tratamento químico, produzidas na safra 2009/2010. Após o recebimento, as sementes foram submetidas à avaliação inicial do teor de água, germinação e sanidade. De acordo com os resultados do teste de sanidade, no qual foi detectada a presença de Alternaria alternata e A. radicina associados às sementes, foram selecionadas sementes de cada espécie, de acordo com a maior incidência dos patógenos. A partir disso, as sementes foram submetidas ao tratamento, de acordo com recomendações dos fabricantes, com fungicida Captan® (na dose de 0,002 g.kg-1) ou com o produto biológico à base de Trichoderma spp., Agrotrich plus® (na dose de 25 g.ha-1), ambos acrescidos ou não de polímero Collorseed - Rigran® (na dose 50 mL. kg-1). Assim, os tratamentos consistiram em: testemunha, semente + fungicida Captan®, semente + fungicida Captan® + polímero, semente + Agrotrich plus®, semente + Agrotrich plus® + polímero. Avaliações de qualidade foram realizadas a cada três meses, ao decorrer de um ano de armazenamento. A qualidade fisiológica foi avaliada através dos testes de germinação, primeira contagem de germinação, teste de frio, comprimento de plântula, emergência e índice de velocidade de emergência e, a qualidade sanitária através do método do papel filtro. O tratamento de sementes de cenoura, coentro e salsa, contaminadas com A. alternata e com A. radicina, com o fungicida Captan® + polímero, favoreceu a qualidade fisiológica e sanitária durante o armazenamento. O Agrotrich plus®, acrescido ou não de polímero, não mostrou eficiência no tratamento dessas sementes durante o armazenamento. Além disso, a incidência de A. alternata e de A. radicina reduziu ao longo de doze meses de armazenamento, independentemente do tratamento aplicado nas sementes de apiáceas.
77

Emprego da radiacao gama do cobalto 60 em sementes de beterraba (Beta vulgaris L.), cenoura (Daucus carota L.) e rabanete (Raphanus sativus L.) para estimular o aumento de producao

BOVI, JOSE E. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:30Z (GMT). No. of bitstreams: 1 07012.pdf: 4436115 bytes, checksum: c7f4ad36e0df97842e6da886b928974f (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
78

Avaliação microbiológica, físico-química e sensorial de salada de repolho com cenoura minimamente processada após o tratamento por radiação gama destinado à pacientes imunocomprometidos ou com dietas especiais / Microbiological, physicochemical and sensory evaluation of cabbage and carrot minimally processed salad after radiation treatment intended to immunocompromised patients or with special diets

NUNES, THAISE C.F. 10 April 2015 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-04-10T16:49:05Z No. of bitstreams: 0 / Made available in DSpace on 2015-04-10T16:49:05Z (GMT). No. of bitstreams: 0 / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
79

Emprego da radiacao gama do cobalto 60 em sementes de beterraba (Beta vulgaris L.), cenoura (Daucus carota L.) e rabanete (Raphanus sativus L.) para estimular o aumento de producao

BOVI, JOSE E. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:45:09Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:04:30Z (GMT). No. of bitstreams: 1 07012.pdf: 4436115 bytes, checksum: c7f4ad36e0df97842e6da886b928974f (MD5) / Tese (Doutoramento) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
80

Avaliação microbiológica, físico-química e sensorial de salada de repolho com cenoura minimamente processada após o tratamento por radiação gama destinado à pacientes imunocomprometidos ou com dietas especiais / Microbiological, physicochemical and sensory evaluation of cabbage and carrot minimally processed salad after radiation treatment intended to immunocompromised patients or with special diets

NUNES, THAISE C.F. 10 April 2015 (has links)
Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-04-10T16:49:05Z No. of bitstreams: 0 / Made available in DSpace on 2015-04-10T16:49:05Z (GMT). No. of bitstreams: 0 / Durante e após o tratamento de câncer, de portadores de HIV ou transplantes, a alimentação pode oferecer um bem estar ao paciente, pois o ato de se alimentar corretamente auxilia as pessoas a se sentirem fortalecidas normalmente. Pessoas saudáveis possuem o seu sistema imunológico funcionando de maneira adequada, podendo combater pequenas quantidades de bactérias. Entretanto, pessoas imunocomprometidas podem não conseguir combater esta pequena quantidade de microrganismos e necessitam de uma dieta com baixa contagem microbiológica para evitar o contato com bactérias potencialmente danosas à saúde. Esta dieta é denominada dieta neutropênica. Esses pacientes são suscetíveis à contaminação alimentar, não sendo aconselhável a ingestão de produtos crus. A irradiação em vegetais, com baixas doses, tem a finalidade de reduzir a carga microbiana. Dessa forma a proposta deste trabalho foi obter dados de aspectos microbiológicos, sensoriais e físico-químicos em Mix Primavera minimamente processados submetidos a diferentes doses de radiação ionizante em dietas destinadas a pacientes imunocomprometidos ou imunossuprimidos. Foram utilizadas doses de 1,0kGy, 2,0kGy, 3,0kGy e 4,0kGy irradiadas no Irradiador Multipropósito 60Co localizado no Centro de Tecnologia das Radiações (CTR) IPEN-CNEN/SP. Foram realizadas análises microbiológicas (n=25), utilizando Petrifilm, análises sensoriais utilizando o teste sensorial de aceitação (n=30) e triangular (n=15) e análise de textura (n=90) no Laboratório de Microbiologia de Alimentos no Centro de Tecnologia das Radiações. As análises de textura foram realizadas com o auxílio de um texturômetro T.A.XT. Plus (Stable Micro System) equipado com a célula de carga de 50kg utilizando a sonda (probe) de corte triangular com lâmina Warner-Bratzler Knife com velocidade de descida de 2mm/s. Todos os resultados foram expressos em Newtons (N). Os resultados obtidos demostraram que para as análises microbiológicas os padrões foram seguidos de acordo com a RDC nº 12/01 ANVISA. A análise sensorial não apresentou diferença significativa entre as amostras, entretanto no teste triangular com as doses de 4,0kGy e controle houve diferença significativa entre as amostras, demonstrando que a amostra de 3,0kGy seria a mais indicada para o público específico deste trabalho. Pode-se concluir que para uma dieta neutropênica sugere-se uma dose de 2,0kGy. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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