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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.
481

Developing phytonematicides using indigenous cucumis africanus and cucumis myriocarpus fruits for tomatoproduction systems

Pelinganga, Osvaldo Manuel January 2013 (has links)
Thesis (Ph. D. Agriculture (Plant Protection)) -- University of Limpopo, 2013 / Global withdrawal of synthetic fumigant and non-fumigant nematicides due to their ecounfriendly impacts and high toxicity to non-target organisms, respectively, increased the research and development of alternatives for managing population densities of plantparasitic nematodes, particularly the root-knot (Meloidogyne species) nematodes. Although Meloidogyne species had been managed using genotypes that are resistant to plant-parasitic nematodes in various crops, various challenges negate the available or introgressed nematode resistance. In tomato (Solanum lycopersicum) production, nematode races and instability of nematode resistant genotypes under certain conditions necessitated the continued research and development of alternatives since most of the existing commercial tomato cultivars are highly susceptible to various biological races of Meloidogyne species. The aim of the study was to research and develop appropriate dosages of two phyto- nematicides which could be applied through drip irrigation system in open field tomato production systems, while the specific objectives were to: (1) determine whether a computer-based model could provide nonphytotoxic concentrations to tomato plants using fresh fruits of wild watermelon (Cucumis africanus) and wild cucumber (C. myriocarpus) under greenhouse conditions, (2) determine whether computer-based concentrations from the two plant species when using dried fruits would be less phytotoxic and more suppressive to nematodes, (3) investigate application time intervals for the two products, (4) determine responses of plant growth in tomato and nematode suppression in respect to the derived dosages, and and (5) validate dosages of fermented crude extracts from the two plant species with respect to plant growth of tomato and suppression of nematode numbers. xxxiii Greenhouse, microplot and field studies were set to test the hypotheses intended to achieve the stated objectives, with reliability of measured variables being ensured by using statistical levels of significance (P ≤ 0.05) and coefficients of determination (R2), while validity was ensured by conducting experiments at the same location over two seasons and/or by setting up factorial treatments. Firstly, fermented plant extracts of fresh fruits from C. africanus and C. myriocarpus consistently reduced population densities of Meloidogyne species by 80-92% and 50-90%, respectively. Tomato plants were highly sensitive to the two products as shown by the total degree of sensitivities (Σk) and biological index of 0 and 3, respectively. Also, the mean concentration stimulation range (MCSR) of 11% and 7% concentrations, respectively, attested to this phytotoxicity. Secondly, fermented crude extracts of dried fruits from C. africanus and C. myriocarpus also reduced population densities of Meloidogyne species by 78-97% and 87-97%, respectively. Tomato plants were highly tolerant to the two products in dried form as shown by the total degree of sensitivities (Σk) and biological index of 4 and 3, respectively. The MCSR values for C. africanus and C. myriocarpus dried fruits on tomato were 2.64% and 2.99%, respectively, which for the purpose of this study were individually adjusted to 3%, which translated to 36 L undiluted material/ha of 4 000 tomato plants. In subsequent studies, 3% concentration was used as the standard, along with double strength concentration, namely, 6% concentration. Thirdly, the MCSR values derived in Objective 4, namely 3% and 6% concentration for both Cucumis species using the CARD model were used in the optimisation of application time interval using the innovative concept of weeks (0, 1, 2, 3 and 4) in a 30-day month period. Application time interval for 3% and 6% concentrations of C. africanus fruits was xxxiv optimised at 2.40 and 2.61 weeks in a 30-day month period, respectively, which translated to 18 days [(2.4 weeks/4 weeks) × 30 days] and 20 days [(2.6 weeks/4 weeks) × 30 days], respectively. In contrast, for both concentrations from fermented crude extracts of C. myriocarpus fruits, application time interval was optimised at 16 days for 2.2 and 2.1 weeks, respectively. During optimisation of application frequencies, fermented crude extracts from C. africanus and C. myriocarpus reduced final population densities of M. incognita race 2 by 70-97% and 76-96%, respectively. Fourthly, optimum application intervals (time), allowed computation of dosage, which is a product of concentration and application frequency (dosage = concentration × application frequency). Fifthly, validation of the dosages under open field conditions suggested that 6% × 16-day dosage under crude extracts from C. myriocarpus fruit significantly (P ≤ 0.05) improved growth of tomato plants when compared with those of either 0% (untreated control) or 3% at 16 days. In contrast, dosages of C. africanus fruit at two application frequency had no effect on growth of tomato plants – suggesting that either of the dosages was suitable for use in tomato production since both reduced nematode numbers. During validation, the materials reduced nematode numbers by margins similar to those observed previously under other environments. In conclusion, crude extracts of the two Cucumis species have stimulatory concentrations which have potential similar reductive effects on population densities of Meloidogyne species and could serve as botanical nematicides. However, since plant responses to the two products differed in terms of their respective dosages and active ingredients, it implied that for further improvement of the two, the overriding focus should be on their interaction with the protected plants and nematode numbers. Ideally, future research xxxv should include environmental impact studies, especially on the influence of the products fruit quality of tomato, earthworms, fish and bees.
482

Investigation of Yield and Quality of Grafted Heirloom and Hybrid Tomatoes

Flomo, Stephen T. 01 May 2010 (has links)
Tomatoes (Lycopersicon esculentum Mill) are one of the most popular vegetable crops grown for fresh market and processing in the U.S. Grafting involves the uniting of a shoot or bud scion with a rootstock to form a compound plant, mainly for managing soil-borne diseases and increasing crop yield. The objectives were to examine the effects of reciprocal and self grafts on tomato fruits, number of fruits, weight, and quality of the cultivars, ‘Cherokee Purple’, ‘Mister Stripey’, ‘Crista’, and ‘Maxifort’. Grafted seedlings were planted at WKU Farm on raised beds, protected with red or black plastic mulch under drip irrigation system with regular supply of water. Matured fruits were harvested, weighed, and number of fruits from each plant recorded. The highest yielding combination was the scion ‘Cherokee purple’ on ‘Maxifort’ rootstock, which produced 304g and 745g heavier fruits than ‘Crista’ and ‘Mister Stripey’, respectively. The quality grade of ‘Crista’ was superior to ‘Cherokee Purple’ and ‘Mister Stripey’ while ‘Mister Stripey’ produced the greatest number of fruits but were of lower quality. Fruits from plants grown on red plastic mulch were significantly larger, heavier, and were of higher quality than those grown on black plastic mulch. However, plants grown on black plastic mulch produced significantly more fruits per plant. There was little advantage for self-grafting of ‘Cherokee Purple’ and ‘Crista’. However, ‘Mister Stripey’ was responsive to self-grafting and merits further investigation. The best rootstock was ‘Maxifort’ which produced the biggest, heaviest fruits of the best quality. ‘Cherokee Purple’ as a scion produced the largest and heaviest fruits, while ‘Crista’ produced the highest quality fruits. ‘Mister Stripey’ was the most prolific in terms of number of fruits per plant.
483

Estudo da desidrata??o de tomates em peda?os com pr?-tratamento osm?tico

Souza, Josilma Silva de 07 June 2002 (has links)
Made available in DSpace on 2014-12-17T15:01:20Z (GMT). No. of bitstreams: 1 JosilmaSS.pdf: 490115 bytes, checksum: b796ab795af867ca3ee2bfaee9a69f80 (MD5) Previous issue date: 2002-06-07 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Vegetables drying plays an important role in the field of food dehydration, being a very old practice that was originated from sun drying items of food in order to preserve them to be consumed during the periods of scarcity. One of these vegetables is the tomato, that was originally grown in South America. Tomatoes are easily perishable after being picked up from the tree and this makes the process of tomato dehydration a challenge due to the high amount of water (95%) contained in them. The present research work was mainly intended to develop alternative processes for tomato conservation, by drying slices of skinned and unskinned tomatoes in the in natura form or in the osmotically pre-dehydrated form. Firstly, the best conditions of the osmotic pre-dehydration process were defined including temperature, immersion time and concentration of the osmotic solution, based on the results of water loss, solids gain and weigh reduction of the pre-dehydration tomatoes at different processing conditions. The osmotic solution used was made up of NaCl (5 and 10%) and sucrose (25 and 35%) at different combinations. For a fixed conditions of osmotic pre-dehydration, the drying tests of the pre-processed and in natura tomatoes were carried out in a stove with air circulation and a convective dryer with trays, at two levels of temperature. The sensorial analysis of the osmotically pre-treated and unskinned dehydrated tomatoes was carried out as well as a study on the their shelf-live. The results obtained showed that the drying of the tomatoes took place as a result of the internal control of the water transport, and did not show a constant rate, while two distinct periods of the decreasing phase were observed. The osmotic pre treatment substancially reduced the initial amount of humidity in the tomatoes, thus reducing the necessary time for the product to attain levels of intermediate humidity. The impermeability of the tomato skin was identified as well as the unfavorable influence of the pre-treatment on the unskinned tomatoes, whose solid gain brought about a decrease in the water activity with subsequent reduction of the drying rate. Despite the various simplifications carried out during the development of this study, the proposed diffusive model adjusted to the experimental data satisfactorily, thus making it possible to determine the effective coefficients of diffusion, whose results were consistent and compatible with those found in the current literature. Concerning the higher rates of evaporation and the lowest processing time, the best results were obtained in the drying of the unskinned, in natura tomatoes and of the skinned, pre-dehydrated tomatoes, at 60?C, both processed in the convective drier. The results of the sensorial analysis of the unskinned and pre-treated product did not prove to be satisfactory. Regarding the shelf-live of the tomatoes, for a period of 45 days, no physicochemical or microbiological alteration of the product was noted / A secagem de hortali?as ocupa uma posi??o muito representativa na ?rea de desidrata??o de alimentos, processo esse que teve in?cio com a secagem ao sol, tem a finalidade de preservar os excedentes das colheitas para serem consumidos nos per?odos de escassez. Dentre estas hortali?as se encontra o tomate, originado da Am?rica, que ap?s a colheita apresenta-se um fruto bastante perec?vel fazendo com que a sua desidrata??o seja um desafio, devido ao seu alto teor de ?gua (95% b.u.). Esse trabalho teve como principal objetivo encontrar formas alternativas de conserva??o do tomate, atrav?s da secagem de peda?os com e sem pele, na forma in natura ou pr?-desidratados osmoticamente. Inicialmente, foram definidas as melhores condi??es da pr?-desidrata??o osm?tica (temperatura, tempo de imers?o, concentra??o da solu??o osm?tica) baseados nos resultados de perda de umidade, ganho de s?lidos e redu??o de peso, dos tomates pr?-desidratados em diferentes condi??es de processamento. A solu??o osm?tica utilizada foi composta de NaCl (5 e 10%) e sacarose (25 e 35%) em diversas combina??es. Para uma condi??o fixa de desidrata??o osm?tica, realizou-se os ensaios de secagem dos tomates pr?-processados e in natura em estufa com circula??o de ar e em secador convectivo de bandejas, em dois n?veis de temperatura. Foi realizada a an?lise sensorial e o estudo de prateleira dos tomates desidratados sem pele e pr?-tratados osmoticamente. Os resultados obtidos mostraram que a secagem dos tomates ocorre sob condi??o de controle interno do transporte de umidade, n?o apresentando per?odo de taxa constante, e verificando-se dois per?odos distintos da fase decrescente. O pr?-tratamento osm?tico reduziu substancialmente a umidade inicial dos tomates, reduzindo o tempo necess?rio para o produto atingir n?veis de umidade intermedi?rios. Foi identificado o car?ter impermeabilizante da pele do tomate, e a influ?ncia desfavor?vel do pr?-tratamento nos tomates sem pele, cujo ganho de s?lidos provocou a diminui??o da atividade de ?gua com conseq?ente redu??o das taxas de secagem. Apesar das in?meras simplifica??es, o modelo difusional proposto ajustou-se de forma satisfat?ria aos dados experimentais, possibilitando a determina??o de coeficientes de difus?o efetivos, cujos resultados mostraram-se consistentes e compat?veis com os encontrados na literatura. Com rela??o as maiores taxas de evapora??o e ao menor tempo de processamento, os melhores resultados foram obtidos na secagem ? 60?C de tomates in natura sem pele e os tomates com pele pr?-desidratados, ambos processados no secador convectivo. Os resultados da an?lise sensorial do produto pr?-tratado e sem pele, n?o foram satisfat?rios. Com rela??o a vida de prateleira, durante um per?odo de 45 dias de armazenamento, n?o se verificou qualquer altera??o f?sico-qu?mica ou microbiol?gica do produto
484

Análise ergonômica do trabalho e exigências laborais em unidades de beneficiamento de tomate de mesa / Ergonomics work analysis and job demands in fresh tomatoes packing houses

Braga, Celso de Oliveira, 1951- 13 February 2007 (has links)
Orientadores: Roberto Funes Abrahão, Mauro José Andrade Tereso / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-09T17:13:35Z (GMT). No. of bitstreams: 1 Braga_CelsodeOliveira_M.pdf: 3029826 bytes, checksum: 206451bcec273e9a42df53573d3a3a39 (MD5) Previous issue date: 2007 / Resumo: A exigência por produtos com boa qualidade e segurança alimentar faz com que o beneficiamento pós-colheita se constitua numa atividade em grande expansão no Brasil. A tomaticultura representa um dos maiores mercados agrícolas brasileiros. O Brasil produz cerca de três milhões de toneladas por ano, sendo dois milhões de toneladas de tomate de mesa. Mais de dez mil produtores e sessenta mil famílias de trabalhadores estão envolvidos nesta produção, o que pode significar duzentos mil empregos diretos. Após a colheita dos tomates, a maior parte da produção é limpa, classificada e embalada em unidades de beneficiamento. Este estudo teve como objetivo a avaliação das exigências laborais nas unidades de beneficiamento de tomate de mesa sob o ponto de vista da ergonomia. Foram selecionadas 06 unidades de beneficiamento de tomate de mesa por amostragem intencional. Aplicou-se o método da Análise Ergonômica do Trabalho para identificação dos postos de trabalho com as maiores exigências laborais no processo de produção. Na pesquisa de campo envolvendo 57 operadores, utilizou-se o Método NASA TLX e o Questionário de Avaliação Visual (QAV), um questionário baseado na Escala de Likert, para avaliar, respectivamente, as exigências mentais e físicas e as exigências visuais das tarefas. Os resultados mostraram exigência mental elevada para 54,3% e exigência física alta para 20,0% dos operadores. Na avaliação da exigência visual constatou-se que 16,3% dos operadores pesquisados apresentaram fadiga visual. Comprovou-se que as exigências laborais, nos postos de trabalho estudados, estão relacionadas ao nível tecnológico dos equipamentos, grau de mecanização no processo de produção, projeto e layout do galpão, aos fatores ambientais e à organização do trabalho nas UB / Abstract: The requirement for good quality products and food safety makes of the processing after harvest an activity in great expansion in Brazil. Tomato cropping represents one of the biggest agricultural markets in Brazil. The country produces about three million tons of tomatoes per year, two million of which are intended for fresh consumption. More than ten thousand producers and sixty thousand families of workers are involved in this production, what may represent two hundred and thousand jobs. After the harvest of tomatoes, the biggest part of the production is cleaned, classified and packed in packing house units. The aim of this research was to evaluate the labor demands in the packing house units of fresh market tomatoes under the point of view of ergonomics. Six packing house units of fresh market tomatoes were selected by intentional sampling technique. It was applied the Ergonomic Analysis of Work method in order to identify the workplaces with the biggest labor demands in the production process. In the field research involving 57 workers, it was applied the NASA TLX method along with a questionnaire based on the Likert Scale in order to evaluate both mental and physical demands as well as visual demands of the tasks. The results showed high mental demand for 54.3% of the workers and high physical demand for 20.0% of them. Concerning to visual demand, it was evidenced that 16.3% of the workers presented visual fatigue. It was evidenced that the workload of the studied workplaces is related to the technological level of the equipment, mechanization degree of the production process, layout and project of the processing house, environmental factors as well as the work organization of the packing house / Mestrado / Planejamento e Desenvolvimento Rural Sustentável / Mestre em Engenharia Agrícola
485

Production de biopesticides pour lutter contre les nématodes à galles des cultures intensives sous abris de tomates au Maroc / Biopesticide production to fight plant parasitic nematodes from intensive tomato cultures grown under greenhouses in Morocco / Produccion de biopesticidas para luchar contra los nematodos de agallas de cultivos intensivos en invernadero de tomate en Marruecos

Tranier, Marie-Stéphane 04 December 2015 (has links)
Ce projet industriel porte sur la production de biopesticides actifs sur les nématodes à galles des cultures intensives de tomates sous abris au Maroc. Les travaux portent sur (i) l’isolement de souches de champignons filamenteux nématophages provenant des sols des cultures infectées par les nématodes, (ii) la réalisation de cultures de ces souches sur un milieu adapté à la Fermentation en Milieu Solide, technique optimale à la biologie des champignons filamenteux et présentant des avantages technologiques et économiques exploitables à une échelle industrielle, (iii) la production de biomasse et de molécules actives extrapolable à une échelle semi-industrielle, (iv) la mise en œuvre d’essais agronomiques pour valider l’efficacité d’un biopesticide produit par FMS dans des dispositifs innovants.24 souches de champignons filamenteux nématophages ont été isolées à partir des sols des cultures intensives de tomate sous serre au Maroc, mais également à partir de produits commerciaux. Le milieu FMS composé de sous-produits agro-industriels permettant une production de l’ordre de 1010 spores par gramme de substrat PS a été validé, et les conditions de cultures des souches établies. 4 dispositifs de Fermentation en Milieu Solide dont un à usage unique, de 300 à 5 000 g ont été mis au point, et ont été protégés par 3 brevets. Enfin, des essais agronomiques de différentes tailles (quelques billons à plusieurs hectares de tomates) ont été mis en place au Maroc de manière à valider l’utilisation de champignons filamenteux actifs contre les nématodes à galles comme étant une alternative écologique à l’utilisation de produits chimiques. / This industrial project involves the production of biopesticides active against root knot nematodes of intensive greenhouse tomato cultures in Morocco. This work focuses on (i) the isolement of nematophagous filamentous fungi from agricultural soils infected with nematodes, (ii) the cultures of these strains on a suitable medium for Solid State Fermentation (SSF), which is the optimal cultural technique for filamentous fungi, presenting technological and economical benefits at an industrial scale, (iii) the production of biomass and active molecules at a semi-industrial scale, (iv) the installation of agronomic assays to validate the effectiveness of a biopesticide production by SSF in innovative devices.24 nematophagous filamentous fungi strains were isolated from intensive greenhouse tomato culture soils, but also from commercial products. The SSF medium composed of agro-industrial by-products allowing a production of about 1010 spores per gram of DW substrate was validated, and the culture conditions of these strains were established. 4 SSF devices including one at single use, from 300 to 5 000 g DW substrate were developed, and were protected by 3 patents. Finally, agronomic assays of different sizes (from few lines to several hectares of tomatoes) were carried out in Morocco in order to validate the use of active filamentous fungi against root-knot nematodes as an ecological alternative to the use of chemical products.
486

Produção de minitomate em sistema orgânico em ambiente protegido / Minitomato production in organic sistem greenhouse

Araújo, Haroldo Ferreira de, 1979- 27 August 2018 (has links)
Orientador: Paulo Ademar Martíns Leal / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agrícola / Made available in DSpace on 2018-08-27T09:53:47Z (GMT). No. of bitstreams: 1 Araujo_HaroldoFerreirade_D.pdf: 6464639 bytes, checksum: 214906b4dba75d9ba4e5b1960486ba8a (MD5) Previous issue date: 2015 / Resumo: O mercado de alimentos orgânicos cresce a cada ano, porém poucas são as pesquisas que abordam esse sistema de produção. Assim, objetivou-se com esta pesquisa avaliar e comparar, em termos quantitativos, qualitativos e econômicos, a produção orgânica de minitomateiro em vasos e canteiros associados às diferentes doses de biofertilizante em três ambientes de casas de vegetação com controle micrometeorológico parcial. A pesquisa foi desenvolvida no campo experimental da Faculdade de Engenharia Agrícola (Feagri/Unicamp), com a cultivar Carolina, conduzida no espaçamento 0,5 x 0,9 m em duas hastes com manejo da adubação orgânica e sistema de irrigação por gotejamento automatizado. Em cada casa de vegetação, utilizou-se o delineamento experimental inteiramente casualizado (DIC) em esquema de parcelas subdivididas com dez tratamentos e cinco repetições. Posteriormente, os dados foram agrupados e reavaliados em análises conjuntas. Os resultados das análises mostraram pouca relevância estatística das doses de biofertilizante sobre as variáveis analisadas, entretanto estas foram significativamente melhores nos canteiros em todas as casas de vegetação, com destaque para a casa de vegetação B quando analisado conjuntamente. As condições micrometeorológicas não foram alteradas entre os ambientes de produção, permanecendo a temperatura e a umidade relativa do ar dentro da faixa adequada para a cultura. A casa de vegetação C, com tela termorrefletora fixa, apresentou a maior altura e o menor diâmetro da haste das plantas, associada à forma de cultivo em vasos, com melhor qualidade dos frutos em termos de sólidos solúveis. A casa de vegetação B, com controle temporal automatizado da tela termorrefletora, mostrou maior produtividade na forma de cultivo em canteiros, bem como a unidade de produção com área mínima de 500 m2 para as condições de investimento, com período payback de 6,54 anos em condições de financiamento pelo Pronaf. A aplicação do biofertilizante Microgeo® via solo não indicou acréscimos produtivos e qualitativos significativos no cultivo do minitomate orgânico / Abstract: The organic food market is growing every year, but few researches on this production system. The objective was to evaluate and compare, in quantitative, qualitative and economic terms, the organic production cherry associated soil bed and pot at different levels of biofertilizer in three different environments greenhouses with partial micrometeorologic control. The research was conducted in the experimental field of Faculty of Agricultural Engineering (Feagri/Unicamp), with Carolina growing, conducted in 0.5 x 0.9 m spacing in two stems with organic fertilization management and automated drip irrigation system. The experimental design for each greenhouse was completely randomized design (CRD) in split plot with ten treatments and five replications (two cultivation forms and five biofertilizer levels), being subsequently grouped and re-evaluated on an analysis. The individual analyzes the research showed little statistical relevance of biofertilizer levels on the variables analyzed, however these were significantly better the soil beds in all greenhouses, especially the B greenhouse when analyzed together. Thus concludes the C greenhouse, with fixed thermal reflector screen, showed the highest height and smaller diameter the stem of plants associated with the form cultivation in pots, with better fruit quality in terms of total soluble solids, while the greenhouse B with automated temporal control of thermal reflector screen, had the highest productivity associated the form of grown in soil beds, as well as the best production unit with a minimum area of 500 m2 for Pronaf investment conditions, and economically viable even for real rates of interest above the prevailing market, with period payback of 6.54 years in financing conditions. The application of biofertilizer Microgeo® the soil showed no significant yield and qualitative increases in organic farming cherry / Doutorado / Construções Rurais e Ambiencia / Doutor em Engenharia Agrícola
487

Influence of container-type and positioning on growth of tomato plants and suppression of meloidogyne javanica exposed to biomuti and afrikelp

Sebati, Mmagadima Lauraine January 2019 (has links)
Thesis (M. A. Agriculture (Plant Protection)) -- University of Limpopo, 2019 / The influence of cultural practices can be modified by environmental conditions such as container-type or positioning. The objective of the study was to determine whether container-type and positioning would have an influence on the growth of tomato plants and suppression of Meloidogyne javanica exposed to biomuti (Trial 1) and Afrikelp (Trial 2). Different container-types were filled with approximately 10.4 L growing mixture comprising steam-pasteurised sandy loam soil and Hygromix-T at 3:1 (v/v) ratio. The containers were established in microplots at 0.6 m × 0.6 m spacing, with treatments being brown pot-below; brown pot-above, black pot-below, black pot-above, plastic bag-above and plastic bag-below. Tomato (Solanum lycopersicum L.) cv. 'Floradade' seedlings were each transplanted and irrigated with 500 ml chlorine-free tapwater every other day. Seven days after transplanting, each plant was inoculated with 2000 eggs and second-stage juveniles (J2) of M. javanica. Biomuti and Afrikelp, obtained from the Agricultural Research Council (ARC) Vegetable, Ornamentals and Plants (VOP), were applied in separate trials weekly at 2.5%. At 56 days after inoculation, plant growth including selected nutrient elements and nematode variables were measured. Data were subjected to analysis of variance, with separation of means achieved using Fisher’s Least Significant Difference test at the probability level of 5%. In the biomuti trial, container-type and positioning had a significant effect on plant height, fruit number, dry root mass, dry shoot mass and fruit mass, contributing 82, 48, 44, 85 and 89% in total treatment variation (TTV) of the respective variables. Relative to brown pot-below; black pot above, plastic bag-above and brown pot-above reduced plant variables, whereas treatment effects were not significant on nematode variables. In the Afrikelp trial, trends where similar to those in biomuti, treatments had highly significant effects on xvi plant height, dry root mass, dry shoot mass and gall rating, contributing 91, 88, 66 and 60% in TTV of the respective variables. Relative to brown pot-below; black pot above, plastic bag-above and brown pot-above reduced the plant variables, but had no significant effects on nematode variables. Generally, plastic bags and polyethylene pots below-ground improved most plant growth variables when compared to those in containers positioned above-ground.
488

Quality protocols for nemarioc-AL and nemafric-BL phytonematicides and potential chemical residues in tomato fruits

Shadung, Kagiso Given January 2016 (has links)
Thesis (Ph. D. (Plant Production)) -- University of Limpopo,2016 / Refer to document / University of Limpopo, The Technology Innovation Agency (TIA), The Land Bank Chair of Agriculture ─ University of Limpopo, The Flemish Interuniversity Council (VLIR) and, The Agricultural Research Council - University Collaboration Centre
489

Control of tomato late blight (Phytophthora infestans) with biocides on tomatoes (Lycopersicum sculentum) in the community of Carmen Pampa, belonging to Coroico municipality (Nor Yungas, La Paz)

Gutiérrez Coarite, Rosemary 01 January 2003 (has links) (PDF)
In Bolivia, tomato acreage is 6717 and has a yield of 12005 kg/ha and the total production is 80,636 TM. Departments that harvest tomato are Santa Cruz, Cochabamba and La Paz, Santa Cruz being the department that shows the highest rates of production with 40653 TM in comparison with La Paz which has a production of 3109 TM and Cochabamba of 2420 TM. The principle factors in affect are, the best climatic conditions in Santa Cruz, while Cochabamba and La Paz have differences in seasonal changes (National Institute of Statistics, 1998). The importance of the tomato harvest lies in consumption preference, for the nutritional properties, as they provide a rich source of Vitamins A and C, principally for its qualities of high productivity in terms of yield per area, being a factor of great importance in the economy of the farmer. The repeated production of tomato in the same area or locality tends to create problems phytopathologicals caused by fungi, bacteria and viruses, that at times become difficult to handle, thus becoming serious limiting factors that are able to seriously affect the yields, as such the investigation of sickness control is of extreme importance. The community of Carmen Pampa belonging to the municipality of Coroico, Nor Yungas, constituting a suitable area for the cultivation of tomato, but the attack of diseases caused by fungi, principally Phytophtora infestans, with an incidence of rate of 98%, which is increased by high temperature, humidity, precipitation and fog, all of which favor the spread of this fungus. For this reason farmers are forced to use chemical products that cause problems of resistance of the causal agent of the illnesses. The FAO (1992) estimates 3 million poisonings annually at a global level of farmers and families as a result of chemicals, which cause in turn a residual effect, environmental pollution and creates and additional cost in production. In the investigation of intoxication by agrochemicals in Bolivia, in a population of 870 persons studied mentioned that, 88% are unaware of the risks associated with the use and management of using them; the cases of poisonings are more frequent in tropical plains with 46%, the valleys with 26%, the inter-Andean valleys with 14% and the high plains with 12%, without mentioning those of suicide origin. For this reason, the object of the present investigation is to try to control the late blight disease (Phytophtora infestans) in the cultivation of the tomato (Lycopersicum sculentum), with biocides, to eliminate or diminish the use of agrochemical products.
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Characterization of Management and Environment Effects on Cultivated Tomatoes

Cao, Chunxue 18 December 2012 (has links)
No description available.

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