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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.
91

Some influences of environment and growth regulating substances on the strawberry plant

Weiss, Hanan. January 1962 (has links)
Call number: LD2668 .T4 1962 W45
92

Phosphorus effects on arbuscular mycorrhizal fungi

Stewart, Lynda Irene. January 2006 (has links)
No description available.
93

The effects of two fungicides on stigma and pollen viability of three strawberry cultivars (F x ananassa) and the impact of these on fruit quality /

Khanizadeh, Shahrokh. January 1983 (has links)
No description available.
94

Phosphorus effects on arbuscular mycorrhizal fungi

Stewart, Lynda Irene. January 2006 (has links)
Two field studies were conducted to assess the potential benefit of arbuscular mycorrhizal (AM) inoculation of elite strawberry plants on plant multiplication, and fruit yield, under typical nursery conditions, in particular soils classified as excessively rich in P. To study plant productivity, five commercially in vitro propagated elite strawberry cultivars ('Chambly', 'Glooscap', 'Joliette', 'Kent', and 'Sweet Charlie') were not inoculated with AM fungi or were inoculated with either a single species (Glomus intraradices), or a mixture of species (G. intraradices, Glomus mosseae, and Glomus etunicatum). AM inoculation was found to impact strawberry plant productivity in a soil with excessive P levels. The AM fungi introduced into the field by inoculated mother plants established a mycelial network in the soil through colonization of the daughter plant roots, however, persistence of colonization was determined to below (<12% in inoculated plant roots). In soils excessively rich in P, individual crop inoculation may be the only option for management of the symbiosis, as the host and non-host rotation crops, planted prior to strawberry production, had no effect on plant productivity or soil mycorrhizal potential. / To study the impact of AM inoculation on fruit production, three commercially grown strawberry cultivars (Glooscap, Joliette, and Kent) were not inoculated with AM fungi or were inoculated with either G. intraradices or G. mosseae. AM fungi impacted the fruit yield, with all inoculated cultivars producing more fruit than noninoculated cultivars during the first harvest year. The percentage of root colonization could not be used to explain the differences in total fruit yield during the first harvest year, or the increase in total fruit yield the second harvest year. / We wished to examine the effects of various P treatments on C metabolism within the intraradical mycelia (IRM) of the fungus. Specific primers were developed for the Glomus intraradices glucose-6-phosphate dehydrogenase (G6PDH) gene. Real-time quantitative reverse transcriptase polymerase chain reaction (QRT-PCR) was used to measure the gene expression of the G. intrarardices G6PDH gene in response to external P conditions of colonized transformed carrot roots. The results showed a significant down-regulation of G6PDH in the IRM of G. intraradices when cultures were grown in a high P (350 muM P) medium compared to those grown in the low P (35 muM P) medium. The down-regulation may suggest a reduction in the C flow from the host to the fungus. There was no effect on G6PDH expression following a two-hour incubation with additional P applications (No P, low P and high P).
95

The effect of sucrose, aspartame, acesulfame-K and blended aspartame/acesulfame-K on orange and strawberry flavor in model solutions

Wiseman, Jennifer Jo 12 August 1991 (has links)
The effect of sweeteners on fruit flavor perception was studied through the use of fruitiness power functions for unsweetened and sweetened model systems. In the first part of the study, two isosweet concentrations of aspartame and sucrose were determined and combined with five concentrations of orange and strawberry flavorants. Fruitiness power functions were developed and compared to determine the effect of each sweetener on the fruit flavor. For the second part of the study in the first experiment, one isosweet concentration of sucrose, aspartame, acesulfame-K and 1:1 blended APM/Ace-K was combined with five concentrations of each of three orange flavorants. Fruitiness power functions were developed and compared to determine how each sweetener effected the fruit flavor of each flavorant. The second experiment addressed the question of whether or not subjects associated sweet taste with fruitiness or if there was an actual change in the volatile composition of the aroma between the unsweetened reference and the sweetened solutions. Fruit aroma of the middle concentration of each flavorant sweetened with the four sweeteners was compared to the corresponding unsweetened reference. Enhancement of fruitiness was observed in the aspartame sweetened systems at low flavor levels. The power function slopes of both flavorants were lowered by the addition of aspartame which resulted in a slower rate of growth in fruitiness perception with the addition of flavorant to the system. In both the orange and strawberry flavored systems the aspartame sweetened solutions were rated higher in fruitiness than the sucrose sweetened solutions. The enhancement was more pronounced in the orange flavored system, suggesting a flavorant effect. The sweeteners affected the fruitiness perception of the three orange flavorants in different magnitudes but the patterns were similar. The three fruitiness slopes were all lowered by the addition of each sweetener. Flavor enhancement was greatest in flavor 1 sweetened with aspartame or aspartame/acesulfame-K. The higher relative placement and low slope of the fruitiness power functions in aspartame sweetened systems caused the enhancement effect to be greatest over the lower concentrations of each flavorant. In the second experiment, the fruit aroma of aspartame sweetened solutions in flavor 1 was significantly higher than the other sweetened solutions. The fruit aroma of the second and third flavorants was not significantly changed by the sweeteners. / Graduation date: 1992
96

Color changes in berries during processing and storage

Gizis, Evangelos John 16 May 1962 (has links)
Graduation date: 1962
97

Occurrence and the exposure potential of selected pesticide residues in strawberries, particularly preformed human malathion biomarkers in leaves and berries

Li, Yanhong, January 2009 (has links)
Thesis (Ph. D.)--University of California, Riverside, 2009. / Includes abstract. Includes bibliographical references. Issued in print and online. Available via ProQuest Digital Dissertations.
98

Indução de resistência a doenças em morangueiro com o uso de Acibenzolar-S-Metil e Harpina em pré e pós-colheita

Tomazeli, Vanessa Nataline 26 February 2010 (has links)
CAPES / O objetivo deste trabalho foi avaliar o efeito dos eliciadores acibenzolar-S-metil (ASM) e da proteína harpina em pré e pós-colheita na indução de resistência a Botrytis cinerea, causador do mofo-cinzento em morangos, e sobre outros agentes infestantes. Quatro experimentos foram conduzidos, dois deles em pré-colheita, e outros dois em pós-colheita. No primeiro experimento (1) em pré-colheita, conduzido em casa-de-vegetação, testou-se dois produtos à base de harpina (ProActTM 2,5 g L-1 com 1% do i.a., e Messenger® 0,75 g L-1 com 3% do i.a) e um à base de ASM (Bion® 500WG 0,5 g L-1 com 50% do i.a.), mais a testemunha (água destilada). Após 24 horas da segunda pulverização dos tratamentos foi realizada inoculação do fungo B. cinerea (105 conídios mL-1). Neste experimento foram avaliadas: produtividade, incidência e severidade da mancha-de-dendrofoma, flores abortadas, incidência de ácaros e incidência de frutos com mofo-cinzento, além do teor de proteínas totais, atividade da enzima fenilalanina amônia-liase (FAL), fenóis totais e taxa de assimilação de CO2. No segundo experimento (2) em pré-colheita, foram testadas doses de harpina (ProActTM 100, 200 e 300 mg L-1) e de ASM (Bion® 500 WG 100, 200, 300 e 400 mg L-1), mais a testemunha (água destilada). Após 24 horas da primeira aplicação dos tratamentos foi realizada inoculação de B. cinerea (104 conídios mL-1). Neste experimento foram realizadas avaliações para os parâmetros de produtividade, incidência de podridões e taxa de assimilação de CO2. Além disso, após a quarta aplicação dos tratamentos, foram coletados frutos para um dos experimentos (4) em pós-colheita. Foram realizados mais dois experimentos em pós-colheita, e o terceiro experimento (3) foi conduzido em parcelas subdivididas, com e sem ferimentos nos frutos. Os frutos foram pulverizados com ASM (Actigar® 50WG 5,0 mg do i.a. mL-1), dois produtos comerciais contendo proteína harpina (80 mg do i.a. L-1 - ProActTM e Messenger®) e uma testemunha (água destilada). Para o quarto experimento (4), frutos tratados em pré-colheita com 100, 200 e 300 mg L-1 ProActTM (1% de harpina), e 100, 200, 300 e 400 mg L-1 de Bion® (50% de ASM), mais a testemunha (água destilada). No experimento 3, os tratamentos foram aplicados por meio de pulverização e 12 horas após efetuou-se a inoculação do fungo B. cinerea (105 conídios mL-1). Após 48 horas da inoculação os frutos foram avaliados quanto à área lesionada e firmeza de polpa. Foi coletada amostra do material vegetal para análise do teor de proteínas totais e da atividade da FAL. Os frutos do experimento 4 foram colhidos do experimento 2, depois da quarta aplicação dos tratamentos. Após a desinfecção em HCl (1%) os frutos foram inoculados com o fungo B. cinerea (105 conídios mL-1) e passadas 96 horas foram avaliadas a área lesionada e a firmeza da polpa. Nos experimentos em pré-colheita foi observada indução de resistência à B. cinerea pelos eliciadores, inclusive com efeito de doses. No experimento 1, verificou-se maior atividade da FAL e maior acúmulo de fenóis totais, sendo estes parâmetros relacionados à redução da porcentagem de frutos podres e a menor incidência e severidade da mancha-de-dendrofoma. Em pós-colheita, no experimento 3, houve redução de área lesionada por B. cinera mediante aplicação dos eliciadores. A atividade da fenilalanina amônia-liase aumentou em relação à testemunha e foi relacionada ao maior controle do mofo-cinzento, como também, à maior firmeza de polpa. No experimento 4, também houve a redução da área lesionada, bem como o aumento da firmeza de polpa com o aumento das doses de ambos os produtos. As doses 300 e 9 400 mg L-1 de ProActTM e Bion®, respectivamente, apresentaram os menores valores de área lesionada e a dosagem de 200 mg L-1 de ambos os produtos apresentou maior firmeza de polpa. / The objective of this work was to evaluate the effects of elicitors acibenzolar-S-metil (ASM) and harpin protein in pre and post harvest in the induction of resistance against Botrytis cinerea, responsible to the gray-mold in strawberries, and about other infestent agents. Four experiments had been led, two of them in pre harvest, and other two in post harvest. The first experiment (1) in pre harvest, was carried out in a greenhouse. It was tested two products from harpin protein (ProActTM 2,5 g L-1 with 1% of i.a, and Messenger® 0,75 g L-1 with 3% of i.a) and one from ASM (0,5 Bion® 500WG g L-1 with 50% of i.a), more the control (distilled water). 24 hours after the second spraying of the treatments was carried through inoculation of B. cinerea (105 conidia mL-1). To this experiment we had also been evaluated: productivity, incidence and severity of the one leaf blight fungus (Dendrophoma obscurans), percentage of aborted flowers, incidence of mites and percentage of fruits with the gray-mold, beyond the content of total proteins, activity of the phenylalanine ammonia-lyase enzyme (PAL), total phenols and the CO2 assimilation rate. In the second experiment (2) in pre harvest, doses of harpin (ProActTM 100, 200 and 300 mg L-1) and of ASM had been tested (Bion® 500 WG 100, 200, 300 and 400 mg L-1), more the control (distilled water). 24 hours after the first application of the treatments inoculation of B. cinerea (104 conidia mL-1) was carried through. In this experiment evaluations for the productivity parameters, percentage of putrid fruits and the CO2 assimilation rate had been carried through. Besides that, after the fourth application of the treatments, had been collected fruits for one of the experiments (4) in post harvest. Two experiments had been led more, in post harvest, the third experiment (3) was led in subdivided parts, with and without wounds in the fruits. The fruits had been sprayed with acibenzolar-Smetil (Actigar® 50WG 5.0 mg of i.a. mL-1), two commercial products having harpin protein (80 mg of i.a. L-1 - ProActTM e Messenger®) and one control (distilled water). The fruits of experiment 4 had been harvested of experiment 2, after the fourth application of the treatments. To the fourth experiment (4), fruits in pre harvest with 100, 200 and 300 mg L-1 ProActTM (1% of harpin), and 100, 200, 300 and 400 mg L-1 of Bion® (50% of ASM), more the control (distilled water), were evaluated in post harvest. In experiment 3, the treatments had been applied by means of spraying and 12 hours after the B. cinerea fungus was inoculated (105 conidia mL-1). After 48 hours of the inoculation the fruits had been evaluated as for the injured area and pulp firmness. Sample of the vegetal material was collected for analysis of the total proteins content and the activity of the PAL. After the disinfection in HCl (1%) the fruits had been inoculated with B. cinerea fungus (105 conidia mL-1) and passed 96 hours had been evaluated the injured area and the firmness of the pulp. In the experiments in pre harvest the induction of resistance against B. cinerea was observed by the use of elicitors, including with effect of doses. In experiment 1, it was verified bigger activity of the PAL and bigger accumulation of total phenols, being these parameters related to the reduction of the 11 percentage of rotten fruits and the smaller incidence and severity of the one leaf blight. In post harvest, in the experiment 3, there was reduction of injured area by B. cinerea through the application of the elicitors. Plants sprayed with the elicitors increased the activity of phenylalanine ammonia-lyase and it was related to the biggest control of the gray mold, as well as, the biggest pulp firmness. In experiment 4, there was also had the reduction of the injured area, as well as the increase of the pulp firmness with the increase of the doses of both the products. The doses of 300 and 400 mg L-1 of ProActTM and Bion®, respectively, had presented the smaller values of injured area, and the dosage of 200 mg L-1 of both the products presented greater pulp firmness.
99

Eficiência no uso de água e de potássio no cultivo e na produção do morangueiro

Gomes, Edilson Ramos [UNESP] 01 August 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:26:47Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-08-01Bitstream added on 2014-06-13T20:34:41Z : No. of bitstreams: 1 gomes_er_me_botfca.pdf: 941970 bytes, checksum: 39260445a5a727a2cbfd5a375221f256 (MD5) / O morangueiro é uma cultura de clima temperado que demanda práticas culturais elaboradas para viabilizar seu cultivo. Dentre estas práticas, a irrigação fornecida por gotejamento visa suprir as necessidades hídricas da planta, em caráter total ou suplementar. Por outro lado, a adubação empregada no cultivo do morango é um dos insumos que gera alto custo na produção. O objetivo do presente estudo foi avaliar as necessidades hídricas da cultura de morango e seu manejo, visando elevar sua produtividade. Além disso, estudou-se a nutrição potássica da cultura, através da aplicação de diferentes doses do nutriente via fertirrigação em combinação com lâminas de irrigação (125%, 100%, 75%, 50% e 25% com base na tensão de água no solo), com o finalidade de elevar a qualidade dos frutos. O experimento foi conduzido em estufa de forma convencional. Em relação à nutrição potássica, foram aplicados três doses na forma K2SO4 as quais consistiram de uma adubação convencional (300 kg ha-1), uma superdose do nutriente equivalente a 3 vezes a dose recomendada (900 kg ha-1) e ausência completa de adubo potássico. Os tratamentos foram dispostos em delineamento experimental em blocos casualizados, com parcelas subdivididas com quatro repetições. A boa disponibilidade de água relacionada com a adubação potássica recomendada proporcionou a maior produtividade, crescimento das plantas e maiores frutos. Quando associadas menor disponibilidade de água e maior adubação potássica as características químicas dos frutos apresentaram melhores resultados. Entretanto, a menor disponibilidade de água e maior adubação potássica proporcionaram problemas fisiológicos e bioquímicos nas plantas / Strawberry is a culture of temperate climate that requires cultural practices developed to make possible its cultivation. Among these practices, the drip irrigation aims to supply the plant water needs, on a full or supplementary way. On the other hand, the fertilizer used in the strawberry cultivation is one of the inputs that generate high cost in production. The aim of this study was to evaluate the strawberry crop water requirements and its management in order to increase the productivity. In addition, we studied the potassium nutrition of the crop using the application of different concentrations of the nutrient by fertigation combined with irrigation water depths (125%, 100%, 75%, 50% and 25% based on the soil water tension) with the purpose of increasing the quality of the fruit. The experiment was conducted in a greenhouse in a conventional way. Regarding to the potassium nutrition, three doses were applied in the K2SO4 form according to the following manners: 1) conventional fertilization (300 kg ha-1); 2) overdose of the nutrient equivalent to three times the recommended dose (900 kg ha-1); 3) absence of potassium fertilizer. The treatments were arranged in a randomized complete block design with split plot with four replications. The good water availability correlated with the recommended dose of potassium fertilizer provided the highest productivity, greater plant growth and larger fruits. When associated the lower water availability with the higher potassium fertilization dose the chemical characteristics of the fruits showed the better results. However, the lower availability of water and the higher potassium fertilization dose have caused physiological and biochemical problems in the plants.
100

Avaliação da eficiência da calda bordalesa, da calda sulfocálcica e do biofertilizante supermagro no cultivo orgânico de morangueiro

Mangnabosco, Marindia Caprini 26 February 2010 (has links)
No Brasil o morangueiro (Fragaria x ananassa Duch), representa um papel sócioeconômico de grande importância nas regiões Sul e Sudeste, constituindo-se num importante produto para consumo in natura e para indústria de alimentos. No entanto, o cultivo intensivo e muitas vezes com práticas culturais inadequadas tornam praticamente inevitável o controle químico de pragas e doenças, constituindo-se, o morango, num dos produtos com maior carga de agrotóxico. Nesse sentido, a produção de alimentos mais saudáveis, isentos de resíduos tóxicos, vem crescendo no mercado nacional e internacional demandando o desenvolvimento de tecnologias mais sustentáveis. O trabalho foi desenvolvido, nos anos de 2007 e 2008, na área experimental da UTFPR - Campus Dois Vizinhos com objetivo de avaliar o comportamento agronômico e as alterações bioquímicas de morangueiros em sistema de cultivo orgânico em função da aplicação de diferentes concentrações de calda bordalesa, calda sulfocálcica e biofertilizante supermagro, o delineamento experimental utilizado foi blocos ao acaso com 4 repetições contendo 16 plantas por parcela. O primeiro experimento realizado em 2007 foi um fatorial misto 3x4 sendo, fator A (qualitativo) constituído pela calda bordalesa, a calda sulfocácica e biofertilizante supermagro e o fator B (quantitativo) representado pelas concentrações de 0,5;1,0;2,0;4,0% e a testemunha onde se aplicou água. A freqüência de aplicações foi a cada 7 dias. No segundo experimento no ano de 2008, os tratamentos foram um fatorial 5x3, onde o fator A foi representado pelas caldas (calda bordalesa a 1%; calda sulfocálcica a 1%; biofertilizante supermagro a 4%, alternância de aplicação de caldas nas mesmas concentrações e a testemunha) e o fator B pelas cultivares (Camarosa, Camino Real e Albion). As avaliações realizadas no primeiro experimento foram: número de frutos por planta, produtividade, massa média, análises físico-químicas dos frutos (firmeza de polpa, acidez titulavel, sólidos solúveis totais - SST, aspecto visual e avaliação degustativa), avaliações de doenças de mancha-de-micosferela e mancha-dedendrofoma e análises bioquímicas em tecidos foliares (proteínas, aminoácidos, açúcares totais e redutores, fenóis totais e atividade de peroxidases). No segundo experimento, foram avaliados os mesmos parâmetros agronômicos, bem como as análises bioquímicas de açúcares totais e redutores, proteínas e atividade da enzima fenilalanina amonialiase. Os dados foram submetidos à análise da variância pelo programa SISVAR e seus resultados submetidos a comparações de médias e regressões. As caldas bordalesa e sulfocálcica, bem como o biofertilizante supermagro interferiram positivamente no número de frutos, massa média e produtividade do morangueiro. Concentrações acima de 1,0% de calda bordalesa e sulfocálcica causaram manchamento dos frutos, limitando seu emprego. O supermagro não apresentou restrição sendo que as melhores respostas agronômicas foram observadas nas maiores concentrações. A firmeza de polpa manteve-se mais elevada em função da aplicação das caldas. A aplicação das caldas e do supermagro interferiu no controle de doenças com redução da severidade da mancha-de-micosferela. A aplicação das caldas não interferiu na qualidade organoléptica dos frutos na pós-colheita, não sendo observado sabor estranho nos mesmos. / In Brazil, the strawberry (Fragaria x ananassa) represents a socio-economic importance in South and Southeast, becoming an important product for fresh market and food industry. However, intensive cultivation and often with inadequate cultural practices make it practically inevitable chemical control of pests and diseases, being the strawberry, one of the products with the highest pesticide load. In this sense, the production of healthier foods, free of toxic waste, is growing in national and international market demanding the development of more sustainable technologies. The study was conducted in the years 2007 and 2008 at the site of UTFPR - Campus Dois Vizinhos to evaluate the agronomic performance and biochemical changes of strawberry in organic cropping system according to the application of different concentrations of bordeaux mixture, lime sulfur and fertilizer supermagro, The experimental design was randomized blocks with four replications containing 16 plants per plot. The first experiment was conducted in 2007 with a 3x4 mixed factorial, factor A (qualitative) consisting of Bordeaux mixture, the spray and fertilizer sulfocácica supermagro and factor B (quantitative) represented by concentrations of 0.5, 1.0, 2.0 , 4.0% and the control where water was applied. The frequency of applications was every seven days. In the second experiment in 2008, the treatments were a 5x3 factorial design, where the first factor was represented by grout (1% Bordeaux mixture, lime sulfur at 1%; biofertilizer supermagro 4%, alternating application of grout at the same concentrations and control) and factor B by cultivars (Camarosa, Camino Real, and Albion). The evaluations performed in the first experiment were: number of fruits per plant, yield, average weight, physical-chemical characteristics of fruits (firmness, acidity, soluble solids - TSS, visual appearance and evaluation gustative), assessments of disease micosferela spot and stain dendrophoma and biochemical analysis in leaf tissues (proteins, amino acids, total and reducing sugars, total phenolics and peroxidase activity). In the second experiment examined the same parameters agronomic and biochemical analysis of total and reducing sugars, proteins and enzyme activity of phenylalanine ammonialyase. The data were subjected to analysis of variance by SISVAR program and its results submitted to mean comparisons and regressions. The Bordeaux mixture and lime sulfur and fertilizer supermagro interfered positively in the number of fruits, average weight and yield of strawberry. Concentrations above 1.0% Bordeaux mixture and sulfur caused staining of the fruit, limiting its use. The supermagro showed no restriction being that the best agronomic responses were observed at higher concentrations. The fimness remained higher depending on the application of grout. The application of the grout and supermagro interfere with disease control with reduced severity of the stain micosferela. Applying the grout does affect the flavor of the fruit after harvesting, were not noticed strange flavor to them.

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