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McGoldrick, Sam J. "Strawberry Fields." Digital Commons at Loyola Marymount University and Loyola Law School, 2017. https://digitalcommons.lmu.edu/etd/310.
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Liu, Bo. "Sustainable strawberry production and management including control of strawberry powdery mildew." Thesis, University of Hertfordshire, 2017. http://hdl.handle.net/2299/19051.
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At present, the global population is increasing, while soil and fresh water resources for crop production are declining. It is important to adopt sustainable practices to optimise the use of limited natural resources without compromising the environment, and to enhance continuous production in the long term. The rapid growth of UK strawberry industry has been achieved through the precision use of varieties, nutrients and polythene tunnels. This intensive production has caused significant environmental impacts especially Greenhouse Gas (GHG) emissions from the production. Strawberry powdery mildew (Podosphaera aphanis) is a major fungal disease affecting strawberry production worldwide particularly in polythene tunnels. The disease can result in yield losses of up to 70% of the crop. A ruleQbased system was used in the field trials to predict high risk days of P. aphanis development, taking into account the optimal environmental conditions conducive to conidial germination and disease development. The results (Chapter 3) showed that the use of this prediction system achieved satisfactory control of P. aphanis in commercial strawberry production, with reduced fungicide applications compared with commercial spray programme. The results were consistent in two consecutive years and on different varieties. In addition, it was suggested that the use of the prediction system may also lead to lower GHG emissions associated with fewer fungicide applications, thereby benefit strawberry growers both environmentally and economically. Results from 2014 & 2015 silicon fertigation trials showed that the use of a silicon nutrient via the fertigation system reduced the strawberry susceptibility to P. aphanis and twoQspotted spider mites (Tetranychus urticae Koch) in two consecutive years on different varieties (Chapter 4). In both years, crops received the silicon nutrient only without fungicides had both lower rate of epidemic (r) and lower value of Area Under the Disease Progress Curve (AUDPC) (r = 0.0036, AUDPC = 475 in 2014; r = 0.001, AUDPC = 267 in 2015) compared with the untreated control (r = 0.0042, AUDPC = 662 in 2014; r = 0.0011, AUDPC = 281 in 2015). Silicon also delayed the epidemic buildQup in the silicon nutrient only treatment for approximately two weeks compared with the untreated control. Crops from the silicon nutrient plus fungicides treatment had lower susceptibility (r = 0.0012 in 2014; r = 0.0004 in 2015) than those from the fungicides only treatment (r = 0.0017 in 2014; r = 0.0005 in 2015) suggesting that the silicon nutrient may also enhance fungicides performance in reducing the epidemic buildQup when used together. Moreover, the presence of T. urticae on strawberry leaves was significantly lower (P < 0.001) in plants treated with the silicon nutrient than those without. In addition, initial results suggested that silicon may play a positive role in raising °Brix of strawberry leaf petiole, improving pollen viability, and influencing the length of flower receptacle and stamens. Maltmas Farm has a wide range of semiQnatural habitats that provide food and nesting resources for wild pollinators. Hoverflies, bumblebees and solitary bees were found to be the main wild pollinators that pollinate commercial strawberries at Maltmas Farm (Chapter 5). The number of pollinators in tunnels or open fields significantly correlated with the abundance of strawberry flowers (P < 0.05). Pollinator presence also differed between groups throughout the day and over the seasons. Hoverflies appeared early in the day and were abundant in summer months; bumblebees and solitary bees were present most of the day and throughout the season, whereas honeybees were only active in sunny days. Temperatures, relative humidity and cloud coverage also affected pollinator presence. In addition, pollinator activity was not significantly (P > 0.05) affected by the application of the silicon nutrient via the fertigation system. The integrated use of the prediction system (to reduce fungicide applications and subsequent GHG emissions), the silicon nutrient (to reduce crop susceptibility to P. aphanis and T. urticae), and sustainable farmland management (to encourage the presence of wild pollinators) could help strawberry growers to achieve a more sustainable production.
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Lu, Nan. "Transposon Tagging in Strawberry and Potato and Characterization of Representative Strawberry Mutants." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/51827.
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Strawberry and potato are both important crop species in the world providing various nutritional values. The cultivated strawberry, Fragaria ananassa, is a fruit crop with a complex genome (2n=8x=56) whereas the diploid woodland strawberry, Fragaria vesca, has a smaller genome (2n=2x=14, 240 Mb) and lots of other qualities that make it a good model for genetic and genomic study, such as high yield of seeds and efficient transformation. Potato (Solanum tuberosum, 2n=4x=48) is an important vegetable crop in the world and is highly heterozygous. The successful sequencing of the homozygous doubled monoploid clone of potato provides good insight into the study of important genes in this species in improving the pest resistance and improving yield. One approach to characterize gene function in a model system is having large populations of T-DNA insertional or transposon tagged mutants. The idea of using AcDs construct to create transposon tagged mutant populations has also been applied in many species. Here we transformed two species, Fragaria vesca and a monoploid potato, Solanum phureja 1-3-516, which is the progenitor of the sequenced doubled monoploid clone, with the same AcDs construct, Ac-DsATag-Bar_gosGFP, to generate mutant collection, compare the marker gene performance and transposition efficiency, as well as characterizing phenotypic mutants with genes of interest. Transposants were found to reinsert to unlinked sites from the launch pad site in the strawberry genome, whereas in potato transposants tended to locate locally from the launch pad position when using the same construct. One transposon based activation tagging strawberry mutant, with its insertion in the promoter region of gene of interest in strawberry from the Ac-DsATag-Bar_gosGFP population was studied. In a segregating T2 population, expression level of the candidate gene, epidermis-specific secreted glycoprotein EP1 precursor, was 670 fold higher in petioles of homozygotes than in wild type plants, suggesting the function of this gene involved in maintaining mechanical strength of petioles. Since the often-used transposase gene was cloned from the monocot species maize, the efficiency of obtaining germinal transposants was many times lower than expected in order to saturate the genome for diploid species. In order to improve the chance of getting unique transposants, we attempted to codon optimize the transposase gene, as well as switching to microspore specific promoters that had been well characterized to control timing of expression of the transposase gene. Transposants were found in both T0 primary regenerates and anther culture derived potatoes using both the pAcDs-AtSCP and pAcDs-AmDEFH125 constructs. Sequencing of the empty donor site revealed that excision occurred in different cells during anther culture. A strawberry mutant with sugar transport deficiency due to T-DNA insertion near a sucrose transporter-2 gene showing stunted phenotype with increased level of anthocyanin was also characterized. The concentrations of sucrose, glucose, and fructose were significantly greater in source leaves of the mutant than wild type plants, suggesting these compounds might be substrates of this gene in transporting to sink leaves and roots.Ph. D.
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Lepine, Yves. "Strawberry handling in Quebec." Thesis, McGill University, 1988. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=61839.
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Jawee, Ahd Abdul Karim. "Studies on the aphid borne virus diseases strawberry mottle and strawberry mild yellow edge." Thesis, University of Reading, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262462.
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Lloyd, Sonja Jane. "Strawberry disease in rainbow trout." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Dissertations/Fall2009/s_lloyd_100609.pdf.
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Ratphitagsanti, Wannasawat. "Processing and properties of strawberry leathers /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1426098.
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SHUMAN, JOEL LEE. "ANTHRACNOSE FRUIT ROT RESISTANCE IN STRAWBERRY." NCSU, 2001. http://www.lib.ncsu.edu/theses/available/etd-20011113-210925.
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The purpose of this research has been to determine the nature of strawberry fruit resistance to anthracnose fruit rot. Production in the United States and North Carolina is heavily dependent upon two cultivars, Chandler and Camarosa. Both cultivars are susceptible to anthracnose fruit rot (AFR), caused by the imperfect fungus . Results from this research will be used to further our understanding of the strawberry- system and to control AFR through breeding strategies or cultural practices. Components of resistance in strawberry to AFR were studied under field and controlled environment conditions; five strawberry genotypes were inoculated with conidia of under field conditions and seven genotypes were inoculated with either five inoculum concentrations or three isolates of in growth chambers. Strawberry genotypes responded differently to in the field and in a controlled environment. Components of resistance to AFR included rate-limiting resistance, reduced percent lesion, reduced probability of lesion formation due to fruit age and genotype, and plant canopy architecture. Rates of disease progress were different among genotypes, inoculum concentrations, isolates, and the genotype x isolate interaction. Susceptible genotypes and virulent isolates had faster rates of disease progress. Differences were observed among genotypes for yield, percent by weight, and number of berries with AFR. Plant canopy architecture influenced the hours of fruit wetness and the yield of berries with AFR; a loose open canopy had fewer hours. Young and old fruit were less susceptible to AFR than fruit of median age.
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Fitter, Yavisht. "Strawberry Detection Under Various Harvestation Stages." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2018.
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This paper analyzes three techniques attempting to detect strawberries at various stages in its growth cycle. Histogram of Oriented Gradients (HOG), Local Binary Patterns (LBP) and Convolutional Neural Networks (CNN) were implemented on a limited custom-built dataset. The methodologies were compared in terms of accuracy and computational efficiency. Computational efficiency is defined in terms of image resolution as testing on a smaller dimensional image is much quicker than larger dimensions. The CNN based implementation obtained the best results with an 88% accuracy at the highest level of efficiency as well (600x800). LBP generated moderate results with a 74% detection accuracy at an inefficient rate (5000x4000). Finally, HOG’s results were inconclusive as it performed poorly early on, generating too many misclassifications.
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Isci, Asli. "Recovery Of Strawberry Aroma Compounds By Pervaporation." Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605084/index.pdf.
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Pervaporation is a selective membrane technique in which a liquid feed mixture is separated by means of partial vaporization through a non-porous perm-selective membrane. This method can be used for the recovery of heat sensitive aroma compounds to avoid them from thermal damage in beverage industries.
The main objective of this study was to determine the effects of feed temperature (30, 40, 50°C), composition (different model solutions, strawberry essence), concentration (50, 100, 150 ppm) and permeate pressure (4, 8 mbar) on the recovery of aroma compounds of strawberry by pervaporation in terms of mass flux and selectivity. In addition, it was aimed to optimize the extraction conditions (extraction time, temperature, agitation speed, strawberry matrix) of Solid-phase microextraction (SPME), which is used for the analysis of strawberry aroma compounds. Optimum results for SPME were obtained at 40°
C, 700 rpm for 30 min and no matrix effect was observed. Pervaporation experiments were performed using a hydrophobic membrane, PERVAP 1070 (PDMS). As the feed temperature increased, the mass flux and selectivity increased and the total mass flux followed an Arrhenius type relation. Decreasing downstream pressure increased both total flux and selectivity, while increase in feed concentration led to higher organic fluxes but lower selectivities. In general, PERVAP 1070 showed a higher selectivity towards Methyl butyrate (MTB) than Ethyl butyrate (ETB) and MTB flux was affected negatively by the presence of ETB in the feed solution. Pervaporation experiments were also performed with a strawberry essence and strawberry model solution. The selectivities of MTB and ETB were negatively affected by the presence of other aroma compounds.
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Buchanan, Aram James. "Genetic determinants of texture in strawberry fruits." Thesis, University of Nottingham, 2001. http://eprints.nottingham.ac.uk/13928/.
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Fruit texture is a quantitative trait believed to be determined by a number of genetic loci. In order to identify genes in strawberries that are specifically associated with texture a cross was made between a cultivar with firm fruits and a cultivar with soft fruits. The resultant population of 269F plants produced ripe fruits whose firmness values differed over a five-fold range. Pools of twenty plants having either the softest or firmest fruits were analysed by two methods. The first, suppressive subtractive hybridisation initially indicated that many genes were differentially expressed in fruits from both the firm and soft pools. Differential hybridisation of 80 subtracted cDNA clones from each pool with the cDNA subtracted from each pool showed that many of the cDNAs were common to firm and soft fruit. When the subtracted cDNAs were hybridised with unsubtracted eDNA several clones from each pool appeared to be enhanced. However, northern analysis was unable to confirm these data. The second method used cDNA-AFLP to detect differentially expressed genes in the pools of firm and soft fruit. Using one set of amplification primers, bands corresponding to 27 cDNA fragments specific to either firm or soft fruit pools were resolved on a polyacrylamide gel. These fragments were cloned and sequenced but they had no obvious homology with genes associated with cell wall metabolism. Northern anlaysis indicated that the cloned cDNA-AFLP fragments represented polymorphisms unrelated to texture. One cDNA clone, AFLP-S 13, appeared to have higher levels of the corresponding transcript in fruits from the soft parent and soft pool. Although this clone was upregulated during ripening its expression was neither fruit specific nor correlated with texture. The expression of genes associated with cell wall metabolism including cell. cel2 and expansin was also investigated in the segregating population.
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Stevens, Matthew Dexter. "Sustainability of cold-climate strawberry production systems." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/2989.
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Thesis (M.S.) -- University of Maryland, College Park, 2005.Thesis research directed by: Dept. of Natural Resource Sciences and Landscape Architecture. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Katsuno, Yoshitaka. "Effect of extrusion cooking on strawberry anthocyanins /." free to MU campus, to others for purchase, 2004. http://wwwlib.umi.com/cr/mo/fullcit?p1421146.
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Maughan, Tiffany L. "Optimizing Systems for Cold-Climate Strawberry Production." DigitalCommons@USU, 2013. https://digitalcommons.usu.edu/etd/2034.
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Producing fruits and vegetables in the Intermountain West can be challenging due a short growing season, extreme temperatures, and limited availability of irrigation water. This is particularly true of strawberries, where commercial production is limited due to late fall and early spring frosts that shorten the growing season. With the increasing demand for local produce as urban populations grow and as consumer buying habits change, growers are looking for ways to overcome these climatic challenges. High tunnels are one option growers can use. High tunnels are similar to greenhouses, but less expensive to construct and to maintain. Another way to protect crops against adverse climatic conditions is with low tunnels. As the name implies, they are a smaller version of a high tunnel, usually only tall enough to cover the canopy of the plant. Low tunnels can be used by themselves or in conjunction with (inside) a high tunnel. Adding heat is another option. However, heating can be expensive and may not be profitable. Targeting heat additions in the root zone may decrease cost of heat but still provide protection to the plant.These protection methods were evaluated in Cache Valley, Utah for effectiveness of increasing strawberry yield. High tunnels increased total yield, as did high tunnels used in conjunction with low tunnels. However, low tunnels by themselves were not able to increase yield in comparison to unprotected plants in the field. Targeted root zone heating was evaluated in both high and low tunnel with two target temperatures: 7 and 15 °C. There was no difference in total yield between the two temperatures, but both increased yield above the high tunnel alone and the 15 °C heating treatment moved the harvest season approximately 6.5 weeks earlier than unheated tunnels and approximately 12 weeks earlier than field production. The additional cost associated with using supplemental heat was offset by the increased yields and the higher value of early fruit.Separate experiments were carried out to determine susceptibility of strawberry leaves to damage from cold temperatures, which can then be used to provide guidelines for temperature management in high tunnels. Strawberry leaves were not significantly damaged when exposed to -3 °C, but significant damage occurred once leaves were exposed to -5 °C. To maximize the advantages of protected cultivation, growers should manage tunnels and heating to keep leaf temperatures above -3 °C. These results provide improved guidelines for growers interested in using protected cultivation strategies to provide fruit for local consumption in the Intermountain West.
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Labadie, Marc. "Deciphering spatio-temporal development of strawberry plant." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0871/document.
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Chez le fraisier la balance entre floraison et développement végétatif incluant la production de stolons (tiges allongées portant les plants filles) conditionne le rendement du plant. L’objectif de la thèse était d’obtenir une meilleure compréhension des processus de développement du fraisier, la floraison, le développement végétatif des axes et le stolonnage, grâce à une étude spatio-temporelle. Trois approches complémentaires ont été développées sur six variétés non-remontantes plantées en conditions « hors sol » : (1) la modélisation des profils d’émergence hebdomadaire de fleurs, feuilles et stolons par une analyse de segmentation longitudinale, (2) l’analyse spatio-temporelle de l’architecture des plants durant une saison de production et (3) le suivi de l’expression de gènes clés liés à la floraison. (1) Les modèles univariés de détection de ruptures appliqués à chaque variable phénologique étaient basés sur l’hypothèse que les changements de phases sont synchrones entre les individus d’une même variété. Ces modèles ont permis d’identifier des phases pour chacune des variétés et chacun des trois types d’organe. Les modèles de détection de ruptures multivariés combinant les trois types d’organes ont permis de mettre en évidence une forte structuration du développement du fraisier par la floraison et le stolonnage. De plus, les variétés se regroupent autour de deux profils de floraison avec la présence ou pas d’un deuxième pic de floraison. Enfin, les modèles d’émergence de stolon montrent un synchronisme suggérant un fort effet environnemental. (2) L’analyse spatio-temporelle de l’architecture s’est basée sur un modèle de graphe arborescent multi-échelle, permettant une représentation visuelle et une analyse de la topologie du plant au cours de son développement. Cette analyse a permis de mettre en évidence des différences topologiques précoces ainsi que différentes stratégies de développement entre les variétés. Ces différences de développement expliquent en partie les différents profils de floraison. (3) Parmi les gènes étudiés pour leur expression au cours de la culture des plants de fraisier, SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) apparait comme un marqueur de développement végétatif et de l’émergence des stolons. Une approche architecturale a également été initiée sur le fraisier diploïde. Les premiers résultats ont permis de mieux préciser le devenir des méristèmes axillaires. En conclusion, ce travail a permis d’évaluer les variétés en condition de production et d’identifier des critères de sélection pour le développement de nouvelles variétés. Il a également permis de développer de nouveaux outils qui pourront être utilisés par les sélectionneurs et les expérimentateursIn strawberry, the balance between flowering and vegetative development, including the production of stolons (elongated stems carrying the daughter plants), conditions the yield of the plant. The objective of the thesis was to better understand the developmental processes of strawberry plant, namely flowering, the vegetative development of axes and runnering, through a spatio-temporal study. Three complementary approaches have been developed on seasonal flowering varieties planted in "soilless" conditions: (1) modeling the weekly emergence of flowers, leaves and stolons by a longitudinal segmentation analysis, (2) spatio-temporal analysis of plant architecture during a seasonal production and (3) expression of key genes related to flowering. (1) Univariate multiple change-point models applied to each phenological variable were based on the assumption that phase changes were synchronous between individuals of a given variety. These models allowed to identify phases for each variety and each type of organ. Multivariate multiple changepoint models combining the three types of organ highlighted a strong structuring of strawberry development by flowering and runnering. Moreover, the varieties can be grouped into two profiles of flowering with the presence or not of a second period of flowering. Finally, the stolon emergence models show a synchronism suggesting a strong environmental effect. (2) Spatio-temporal analysis of the architecture relied on a multi-scale tree graph allowing visual representation and topological analysis of plant development. This analysis revealed early topological differences as well as different strategies of development between varieties. These differences in development partially explain the different flowering patterns. (3) Among the genes studied for their expression during the cultivation of strawberry plants, SUPPRESSOR OF OVEREXPRESSION OF CONSTANS1 (SOC1) appears as a marker of vegetative development and stolon emergence. An architectural approach was also initiated on the diploid strawberry. First results allowed to better specify the fate of axillary meristems. In conclusion, this work allowed to evaluate the varieties in production condition and to identify selection criteria for the development of new varieties. It has also allowed the development of new tools that can be used by breeders and experimenters
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Raman, Uthaya Kumari K. "The role of cytokins in the growth and development of Fragaria x ananassa Duch." Thesis, University of Cambridge, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274166.
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Buddie, Alan Graham. "Systematics of colletotrichum pathogens associated with strawberry plants." Thesis, Royal Holloway, University of London, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.287902.
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Species of the genus Colletotrichum Corda are responsible for many diseases of economically important crops world-wide. One particularly susceptible crop is strawberry (Fragaria spp.) on which Colletotrichum spp. cause extremely destructive anthracnose diseases, characterised by black necrotic lesions on any part of the plant. Three "species" have been implicated in the disease: C. acutatum, C. jragariae, and C. gloeosporioides. C. acutatum is considered the causal organism of strawberry blackspot in Europe and is subject to quarantine regulations within the EU; c.jragariae has only been found in the Americas and was formerly considered the sole cause of strawberry anthracnose in North America; and C. gloeosporioides is a heterogeneous "species aggregate" which has a morphological range which can encompass examples of other "species", especially C. jragariae. The absence of a reliable test for distinguishing these "species" - classical morphological approaches are unsatisfactory - led to an international multi-disciplinary project to characterise Colletotrichum pathogens of strawberry and develop diagnostic tests for individual taxa (\,,,;,,,\..c_,,\_ \:x~ t:k._ ~0). The research reported in this thesis has demonstrated the utility of a multidisciplinary approach to the systematics of Colletotrichum pathogens of strawberry. Data obtained have supported taxon groupings at different levels. The use of mtDNA provided data of two complementary types. Firstly, the NMS primers were utilised in amplification of a fragment of "species aggregate" -specific size (with three notable exceptions) from the mitochondrial small subunit rDNA. Secondly, the Hae III restriction digests of A+T-rich DNA were able to highlight groupings below the level of species aggregates. This latter method was able to distinguish the meioticallyreproducing strains of C. jragariae from anamorphic isolates and elicited two distinct subgroups in C. acutatum. PCR techniques previously described by Mills and co works and Freeman and Rodriguez were assessed for their utility and reliability. Isozyme analyses were moderately useful for taxon differentiation at an infraspecific level with the esterase systems.Study of extracellular enzyme activities using 4 MU substituted compounds was of limited diagnostic use. Additional physiological and biochemical tests did not reveal many discriminatory tests. A few tests, however, did reflect the greater vigour generally displayed by C. jragariae isolates. Utilisation of glucuronamide and growth rate on casein were two such tests. The physiological and biochemical tests were demonstrably more useful when put together with the data from EU Project colleagues and subjected to cluster analyses and ordination techniques, then when analysed as discrete tests. Colleagues in collaborating laboratories undertook a battery of tests including molecular, physiological and biochemical studies. It is appropriate to use the entire set of information obtained from the overall EU-Project in order to fully define the groups. The results reported in this thesis can stand alone, however, allowing discrimination of the taxa at several levels.
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Sampson, Clare. "Management of the western flower thrips on strawberry." Thesis, Keele University, 2014. http://eprints.keele.ac.uk/2133/.
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The western flower thrips, Frankliniella occidentalis (Pergande), is an increasing problem in UK strawberry crops. The use of polythene tunnels has provided a more favourable environment for the pest, and pesticide-resistant strains have resulted in control failure. There is a need for improved knowledge of thrips biology and for additional control methods that can be integrated with natural enemies in order to make thrips management programmes more robust. The distribution of, and damage caused by, F. occidentalis was investigated to improve monitoring and decision-making, and the viability of using traps as a control was tested. Over 74% of adult thrips on plants were in flowers. Twice as many adult thrips were found in mature flowers at the top of the plant compared to those at the side. The distribution of larvae between flower and fruit stages varied with thrips density. All stages of flower and fruit were susceptible to damage but thrips larvae caused more damage than adults per individual, so the distribution and numbers of larvae between fruit stages best predicted the timing of damage. The predatory mite Neoseiulus cucumeris Oudemans reduced damage by feeding on thrips larvae. Economic crop loss occurred at five adult thrips per flower in the absence of N. cucumeris, but up to about 11 adult thrips per flower with good mite establishment. Adult F. occidentalis females overwintered on strawberry and on weeds, resulting in more thrips in second-year than in first-year crops. Mass trapping using blue sticky roller traps caught sufficient adult thrips to reduce fruit damage by 55-68% and increased grower returns by an estimated £2.2k per hectare. The addition of the F. occidentalis aggregation pheromone, neryl (S)-2-methylbutanoate, to the traps doubled the trap catch, but a visual stimulus was essential for trapping. (R)-lavandulyl acetate reduced trap catch, suggesting that it is not part of the aggregation pheromone.
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Reid, James. "The suitability of strawberry cultivars for mechanical harvesting." Thesis, University of Strathclyde, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372112.
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Jambagi, Shridhar. "Molecular studies of plant-pathogen interactions in strawberry." Thesis, University of Reading, 2014. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.602468.
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Powdery mildew is an important disease of crop plants. In strawberry, the disease is caused by the obligate biotrophic fungus Podosphoera ophonis (syn: Sphoeratheco mocu/oris f. sp. Fragorioe) and causes significant economic loss in the cultivated strawberry. This study used the diploid species Fragorio vesco as a model to study plant pathogen interactions. Initial studies involved in the identification of mildew resistance locus 0 (MLO) genes in the diploid species, F. vesco f. vesco and identified 17 FvMLO genes. Real-time quantitative PCR (qRT-PCR) results showed differential expression of 12 FvMLO genes in four strawberry varieties, F. vesco f. vesco (Fv), F. vesco ssp. vesco accession Hawaii 4 (HW), F. vesco f. semperf/orens line "Yellow Wonder 5AF7" (YW) and Eluica (octoploid strawberry). The FvML03 gene which is orthologous to the Arabidopsis AtML02, AtML06 and AtML012 and tomato S/ML01 genes required for powdery mildew susceptibility was highly expressed (164 fold) in YW compared to other FvMLO genes across varieties. The results showed that FvMLO genes can be used as potential candidates to engineer powdery mildew resistance in strawberry based on MLO suppression. To investigate the molecular mechanism underlying strawberry-powdery mildew interaction, RNA-seq was employed to generate a large transcriptome dataset in HW and YW at 1 d and 8 d after powdery mildew infection. We identified about 999 million (92%) reads mapped to the F. vesco genome. Transcripts were identified from a total of 23,470 and 23,464 genes in HW and YW, respectively at all three stages (control, 1DAI and 8DAI). Differential gene expression analysis identified 1,567, 1,846 and 1,145 upregulated genes between control and 1DAI, control and 8DAI, and 1DAI and ! lDAI, respectively in HW. Similarly, 1,336, 1,619 and 968 genes were upregulated in YW. Also 646, 1,098 and 624 down regulated genes were identified in HW, while 571, 754 and 627 genes were downregulated in YW between all three stages, respectively. The study also investigated differentially expressed genes (log2 fold changes <:5) between control and 1DAI in both HW and YW. A large number of genes related to secondary metabolism, signal transduction, transcriptional regulation and disease resistance were expressed predominantly either in HW or YW. These included flavonoid 3' -monooxygenase, peroxidase 15, glucan endo-1, 3-beta-glucosidase 2, receptor-like kinases, transcription factors, germin-like proteins, F-box proteins, NB-ARC and NBS-LRR proteins. This first application of RNA-seq to any pathogen interaction in strawberry provides wealth of genomic information for future studies in understanding molecular and cellular processes of the strawberry defence response to powdery mildew. It was also shown that metabolic lSN hydroponic isotope labelling of entire plants (HILEP) can be achieved in strawberry for quantitative proteomics analysis.
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Alarfaj, Rashed Abdulrahman. "Characterization of a new octoploid strawberry breeding population." Thesis, University of Reading, 2017. http://centaur.reading.ac.uk/75514/.
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Among the Fragaria species, the cultivated strawberry Fragaria × ananassa (2n=8x=56) is the most economically valuable crops. After harvest, they are extremely perishable, have a short shelf life, and are susceptible to mechanical injuries and physiological decay due to loss of tissue integrity, sensitivity to fungal diseases, and have a large surface area, which lacks an outer protective rind. Therefore, maintaining high nutritional values in the berry fruit whilst maintaining high fruit quality requires an understanding of the genetic and environmental effects on each trait, and how different traits are associated with each other. Mapping traits on the linkage map using a Quantitative Trait Loci (QTL) approach is the first step to identify the underlying gene(s) and to explore their effects and interactions. It will improve our understanding of the genetic control of measured traits and facilitates molecular marker development. Therefore, it can be used to improve plant-breeding efficiency at the molecular level, which significantly reduces the breeding time and cost of phenotyping. The overall aim of this study was to characterise the variation in quality traits among the F1 mapping progeny derived from a cross of Redgauntlet x Hapil (RGxH) strawberry cultivars. These traits include total soluble solids (TSS), titratable acidity (TA), fresh weight, surface colour, firmness, and phenolic content. This thesis presents two areas of work. First, using a novel high-density single nucleotide polymorphism (SNP) linkage map, phenotyping plant characteristics of RG x H progeny enabled the detection of QTL linked to traits associated with shelf life (at 4 °C). Subsequent QTL analysis highlighted 47 QTL linked to quality traits associated with three post-harvest days in two sequential seasons (2013 and 2014). Among them, three major QTL for fruit lightness (L*value) and TSS/TA ratios were detected in 2013, whereas 17 major QTL were detected in 2014, of which three accounted for >30 % of phenotypic variance. Study results provided additional data on the genetic architecture of fruit quality traits across shelf life at points relevant for strawberry breeding. However, it is still necessary to confirm the stability of the identified QTL resulting from the study findings. Second, the study evaluated the flavour profiles of seven genotypes of the RGxH F1 strawberry population and their parental lines in order to assess correlations between sensory and instrumental data. Ten trained sensory panellists rated strawberry puree samples on day 1 and day 5 of storage. Thirty attributes were evaluated, including odour, taste, flavour, mouth sensation and aftertaste. Gas chromatography systems were coupled with the solid-phase micro extraction (SPME) method to determine volatility of organic compounds. The results showed a clear separation between desirable attributes, which correlated with most day 1 samples, and undesirable attributes, which correlated with most day 5 samples. Furthermore, the results confirmed the role that volatile compounds (mainly esters, terpenes and aldehydes) and some physical traits (mainly TSS, TA and their ratios) play in sensory perception.
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Vargas, Ronald G. "Feasibility of custom strawberry farming in Oceanside California." Thesis, Kansas State University, 2013. http://hdl.handle.net/2097/19753.
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Master of AgribusinessDepartment of Agricultural Economics
Allen M. Featherstone
The objective of this thesis is to determine if contract farming of fresh strawberries in Oceanside California is financially feasible. This is being considered as an alternative to managing the 185 acre fresh strawberry farm. The farming business is owned by a large fresh fruit marketing firm. As an independent custom grower I would not be subject to the same constraints as the marketing firm. No changes to management structure or product quality would be necessitated by this change. Assumptions for this study are specific to operating requirements for producing winter strawberries in North San Diego County in California. The cultural practices described and inputs used are considered to be usual for a well-managed commercial farm. The cost and returns are based upon actual historical data and representative of similar if not exact cultural practices and material inputs. The conceptual model used to guide the development of this study was taken from a generic feasibility study framework. It served as a controlled process to analyze the situation and determine the financial outcomes. The economic and financial viability analysis includes costs and returns per acre, monthly cash costs, sensitivity analysis, and overall profitability. The method used to assess the dimensions of viability was to weight them by evaluating key characteristics for relative strengths and weaknesses. The recommendation based upon this assessment is that the overall viability of the proposal is more than 80% and therefore merits the development of a comprehensive business plan.
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Basson, Carin Elizabeth. "Analysis of intermediate carbon metabolism in strawberry plants." Thesis, Link to the online version, 2008. http://hdl.handle.net/10019/1907.
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Carpenter, Christopher E. "IMPACT OF ULTRAVIOLET ENERGY ON STRAWBERRY SHELF LIFE." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1885437591&sid=5&Fmt=2&clientId=1509&RQT=309&VName=PQD.
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Huang, Yuehe 1955. "Comparison of photosynthetic capacity between two strawberry genotypes." Thesis, The University of Arizona, 1990. http://hdl.handle.net/10150/276338.
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Amount and activity of the primary carboxylating enzyme of photosynthesis, photosynthetic gas exchange, and leaf anatomical parameters were measured in two strawberry species, RCP37 (Fragaria chiloensis) and 'Midway' (Fragaria x ananassa). Photosynthetic capacity was greater in RCP37, as indicated by a greater CO₂ assimilation rate at ambient CO₂ concentration (350 μmol mol⁻¹), Rubisco amount, carboxylation efficiency, residual conductance, ratio of mesophyll surface area to leaf area, and leaf N content, compared to 'Midway'. The ratio of mesophyll surface area to leaf area, mesophyll layer thickness and palisade layer thickness were significantly different between RCP37 and 'Midway'. The large surface area of palisade cells in RCP37 accounted for the difference in the ratio of mesophyll surface area to leaf area. Results show that RCP37 has higher photosynthetic capacity than 'Midway'. RCP37 might provide promising resources of germplasm for improving photosynthetic rate or yields of cultivated strawberry varieties.
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Poole, Mervin C. "The role of pectinesterase in fruit ripening." Thesis, University of Nottingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.342021.
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Alsheikh, Muath. "Genetic transformation of Fragaria vesca L. to allow study of the effects of genes controlling flowering time." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.325197.
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Tehranifar, Ali. "The chilling requirement and dormancy of Fragaria x ananassa cv. Elsanta." Thesis, University of Reading, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363439.
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McArthur, David Albert James. "Strawberry and cranberry response to growth regulators and fertilizers." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/26450.
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The growth and yield response of strawberry (Fragaria X annassa Duch.) and cranberry (Vaccinium macrocarpon Ait) to various growth inhibitors, but especially to paclobutrazol (PP333), and fertilizers were investigated in glasshouse and field studies. PP333 decreased vegetative growth in a rate-dependent manner in both strawberry and cranberry. PP333 delayed fruit ripening in strawberry and decreased fruit set and fruit size in cranberry. PP333 decreased pollen germination of strawberry. Soil residues of PP333 were biologically active when measured 11 weeks after application in the strawberry study and when measured after 50 weeks in a cranberry study. In a field study with cranberry, PP333 caused a decrease in vegetative growth and an increase in flowering in the next season after treatment.
Two-dimensional partitioning was used to account for yield variation from treatment effects on adjusted yield variates. The truss number was the most important contributor to yield variation in the strawberry, but was not affected by treatments. PP333 made a substantial contribution to yield variation in strawberry through its effect on fruit development and ripening. In the cranberry, fruit set was the major contributor to yield variation and PP333 influenced yield substantially through its effect on fruit set.
In glasshouse studies, PP333 decreased shoot elongation in cranberry within 3 weeks of application, and increased the number of branches on primary shoots. Buds were formed within 7 weeks of treatment and some of the buds contained flowers. Shoot growth was greater with a high rate of NPK fertilizer than with the low fertilizer rate and was greater in peaty soil than in sandy soil. While bud set was not modified by soil type or fertilizer rate, high NPK fertilizer decreased floral induction. Some effects of PP333 treatment were decreased by gibberellic acid, but generally these effects here not reversed. In a field study with the cranberry, PP333 increased flower bud set for flowering and non-flowering uprights but slightly decreased floral induction for non-flowering uprights.Land and Food Systems, Faculty of
Graduate
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Willig, Jennifer A. "Analysis of Antiviral and Chemoprotective Effects of Strawberry Anthocyanins." UKnowledge, 2013. http://uknowledge.uky.edu/animalsci_etds/28.
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This study investigated the antiviral, chemoprotective and proliferative effects of strawberry anthocyanins on herpes simplex virus type-1, cancerous cell lines HT-29 and AGS, and normal cell lines Hs 738.St/Int and CCD-18Co. Antiviral properties were measured by infecting vero cells from adult grivet (Cercopithecus aethiops) with herpes simplex virus type-1 (HSV-1) and treating with a concentration of 1.25-20 µg/mL of strawberry anthocyanins. Infectivity and replication were quantified for herpes simplex virus type-1 using the direct plaque assay and reporting PFU/mL. Strawberry anthocyanins (>20 µg/mL) inhibited the herpes simplex virus infectivity in vero cells by 100% (p<0.05). Strawberry anthocyanins at concentrations of 5, 10 and 20 μg/mL were reduced to 75.36, 57.98, and 31.46 percent of the control (100%) (p<0.05).
Chemoprotective and proliferative effects of strawberry anthocyanins were analyzed for the human cell lines AGS, Hs 738.St/Int, HT-29, and CCD-18Co at a concentration of 25-200 µg/mL and quantified using the sulforhodamine-B assay. Growth inhibition occurred at a level of ≥87% for treatment concentrations 100 and 200 µg/mL for the cancerous AGS and HT-29 cell lines (p<0.0001). Proliferation rates for the normal Hs 738.St/Int and CCD-18Co cell lines increased at all treatment concentrations of 25-200 μg/mL (p<0.0001); suggestingthat the observed proliferative activity may be associated with anthocyanin treatment.Strawberry anthocyanin treatment concentration worked in a dose dependent manner for the HSV-1 and the cancerous AGS and HT-29 cells. The caspase-3 assay was performed to demonstrate potential mechanism of action and confirmed thatanthocyanin treatments play a role in apoptosisby the up regulation of caspase-3.Significantdifferences were seen between the growth characteristics of cancerous cell linescompared to their equivalent normal cell lines (p<0.0001).
In summary, the antiviral findings suggest that strawberry anthocyanin extracts could be an effective topical treatment and/or prophylactic agent for oral herpetic infections (HSV-1). Also, the in vitro chemoprotective effect of strawberry anthocyanins found may be relevant to in vivo work in the future because when anthocyanins are consumed in the diet they come in direct contact with the gastrointestinal tract and may provide chemoprotection upon contact with the stomach and gastrointestinal tract’s epithelial cell layer.
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Santos, Francisco SÃrgio Ribeiro dos. "Production and nutrition in strawberry crop soil and hydroponic." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13165.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel SuperiorTraditional soil based strawberry production currently faces some obstacles, both by excessive use of pesticides, as the diseases caused by fungi and other pathogens and ergonomic difficulties of cultivating the soil. Strawberry soilless cultivation combined with greenhouse and the use of substrate promotes some advantages such as: eliminating the use of products for soil disinfection, precocity, increased yields, better crop management conditions and crop protection against adverse weather conditions, pest attacks and diseases.. The objective of the study was to evaluate yield and nutrition of four strawberry cultivars in three cropping systems in Serra da Ibiapaba â CearÃ. The experiment was conducted in 3 x 4 factorial design, randomized blocks, with three cultivation systems arranged in strips (soil, hydroponic in gutters and bags), with four strawberry cultivars (Oso Grande, Albion, and Camarosa and Festival) and five replications. Coconut fiber was used as substrate in the hydroponic systems. In the period between the sixth and thirty-eighth week after transplanting, the number and average fruit weight, yield per plant and yield were determined. From the beginning of flowering, leaves were collected every two months to determine the levels of macro and micronutrients. Hydroponic gutter and bag systems increased the number of fruits per plant, but did not increase average fruit weight. The strawberry yield in hydroponic cultivation system was superior to soil cultivation. Cultivar Festival presented more fruits than the other cultivars in hydroponic systems. The Oso Grande and Festival cultivars stood out as the average fruit weight and yield, respectively, and may be recommended for hydroponic cultivation for the region of Serra da Ibiapaba. Based on the leaf nutrient contents, it is suggested adjustments in concentrations of phosphorus and magnesium in the nutrient solution used in hydroponic strawberry crop. Keywords: Fragaria x ananassa, cultivar, nutrients, crop system,
O cultivo do morangueiro no solo enfrenta atualmente alguns entraves, tanto pelo uso excessivo de defensivos, como pelas doenÃas causadas por fungos e outros patÃgenos e as dificuldades ergonÃmicas do cultivo no solo. O cultivo em sistemas sem solo combinado com ambiente protegido e o uso de substrato proporciona algumas vantagens como: eliminaÃÃo do uso de produtos destinados à desinfecÃÃo do solo, antecipaÃÃo do inÃcio das colheitas, aumento da produÃÃo, proteÃÃo da cultura Ãs condiÃÃes meteorolÃgicas adversas, ataque de pragas e doenÃas e melhores condiÃÃes de manejo da cultura. O experimento teve como objetivo avaliar a produÃÃo e nutriÃÃo de quatro cultivares de morango em trÃs sistemas de cultivo na Serra da Ibiapaba â CearÃ. O experimento foi conduzido em esquema fatorial 3 x 4, em blocos casualizados, sendo trÃs sistemas de cultivo dispostos em faixa (solo, hidropÃnico em calhas e em s a c o l a s ), com quatro cultivares de morangueiro (Oso Grande, Albion, Camarosa e Festival), com cinco repetiÃÃes. No sistema hidropÃnico foi utilizado como substrato fibra de coco. No perÃodo entre a sexta e trigÃsima oitava semana apÃs o transplantio, foi determinado o nÃmero e peso mÃdio de frutos, produÃÃo por planta e produtividade. A partir do inÃcio do florescimento, foram coletadas a cada dois meses folhas para determinaÃÃo dos teores de macro e micronutrientes. Os sistemas hidropÃnicos em calha e em sacolas aumentaram o nÃmero de frutos por planta, porÃm nÃo aumentaram o peso mÃdio de frutos. A produtividade do morangueiro cultivado no sistema hidropÃnico foi superior ao cultivo no solo. A cultivar Festival apresentou maior nÃmero de frutos em relaÃÃo as demais cultivares nos sistemas hidropÃnicos. As cultivares Oso Grande e Festival destacaram-se quanto a peso mÃdio de frutos e produtividade, respectivamente, sendo recomendadas para cultivo hidropÃnico para regiÃo da Serra da Ibiapaba. Com base nos teores de nutirentes na folha sugere-se ajustes nas concentraÃÃes de fÃsforo e magnÃsio na soluÃÃo nutritiva utilizada no cultivo hidropÃnico do morangueiro. Palavras-chaves: Fragaria x ananassa, cultivar, sistema de cultivo, nutrientes.
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Ferguson, Carolyn May Jane. "ELISA detection of Bacillus subtilis L-forms in strawberry." Thesis, University of Aberdeen, 1998. http://digitool.abdn.ac.uk/R?func=search-advanced-go&find_code1=WSN&request1=AAIU179877.
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An Enzyme-Linked Immunosorbent Assay (ELISA) was developed for the detection of Bacillus subtilis L-form bacteria in pure culture and in strawberry plant material. Investigations led to the use of an assay where the enzyme, alkaline phosphatase was bound to streptavidin and was one of the components of the avidin-biotin amplification step. The polyclonal antibodies used were shown to be selective for Bacillus subtilis L-forms, with the cell-walled parent and other Bacillus species also being detected, but only at much higher population numbers. Detection limits for the biotin-ELISA were established by preparing standard curves of L-forms from pure culture suspended in plant extracts from micropropagated strawberry tissues and mature strawberry plants. These were 10 3 viable cells ml-1 in 10% mannitol, 104 ml-1 in extracts of micropropagated shoots and 106 ml-1 in mature plant extracts. This enabled the L-form status of micropropagated strawberry shoots and mature, glasshouse-grown plants to be monitored during the development of appropriate association techniques. Detailed investigations showed that L-forms, introduced to micropropagated strawberry shoot explants, were maintained throughout their growth (9 weeks), as well as after subculture i.e. 19wk after L-form treatment. L-form bacteria sprayed directly into the surface of micropropagated strawberry plants were antagonistic towards the fungal plant pathogen Botrytis cinerea. Glasshouse-grown strawberry plants were injected with L-forms and ELISA was used to monitor the distribution of L-forms in different plant parts up to 14d after treatment. L-form bacteria were randomly distributed throughout the plants within 4 days and detected in leaves, petioles, runners and crowns. A large experiment undertaken in a polythene tunnel monitored the presence of L-forms, at t = 1 and 11wk, in plants treated with B. subtilis L-form bacteria (test) , or 10% mannitol (control). The ELISA showed L-form presence in all test plants (n = 50) and, although post-harvest spoilage was shown to be delayed, there was no correlation between L-form presence and reduced port-harvest spoilage. This is discussed along with other aspects concerning the symbiosis(ses) of L-form bacteria with strawberry plants.
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Gasparrini, Massimiliano. "Effect of strawberry antioxidants against oxidative and inflammatory stress." Doctoral thesis, Università Politecnica delle Marche, 2016. http://hdl.handle.net/11566/243099.
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Il primo obiettivo dello studio è stato quello di valutare e confrontare la qualità fitochimica e nutrizionale di diversi estratti di fragola, prodotti da varietà commerciali ottenute da specifici programmi di incrocio genetico. Nei vari estratti sono state misurate la capacità antiossidante totale, l'attività anti radicalica e il contenuto di polifenoli, flavonoidi, antociani, vitamina C e folati. Sulla base dei risultati ottenuti la cultivar Alba è stata scelta per condurre le analisi nella seconda parte del progetto. Il secondo obiettivo è stato quello di valutare gli effetti di estratti metanolici della cultivar Alba sull’infiammazione indotta dal LPS di E.Coli in cellule di fibroblasti di derma umano e macrofagi RAW 264.7. Dopo analisi preliminari di vitalità, apoptosi e produzione di ROS intracellulari, il ruolo protettivo degli estratti è stato stimato attraverso la valutazione dei principali biomarcatori collegati allo stress infiammatorio e ossidativo e in relazione all'attività dei principali enzimi antiossidanti. Analisi di espressione proteica sono state effettuate per identificare le principali vie molecolari coinvolte nell’azione degli estratti di fragola e del LPS E’ stato inoltre misurato il consumo di ossigeno correlato alla funzionalità mitocondriale. I risultati hanno evidenziato come gli estratti di fragola esercitino un effetto anti-infiammatorio sulle cellule trattate con LPS, riducendo la produzione di ROS e abbassando i livelli dei biomarcatori infiammatori e ossidativi. La risposta infiammatoria è stata altresì contrastata rafforzando l’attività antiossidante e regolando le vie molecolari collegate all’AMPK, registrando inoltre un miglioramento della funzionalità mitocondriale. I risultati ottenuti sottolineano e confermano il potenziale beneficio per la salute di un consumo di fragola, in particolare nei confronti delle alterazioni indotte da stress infiammatori.The first aim of this PhD project was to assess and compare the nutritional and phytochemical quality of strawberry fruit extracts of different cultivars and/or varieties, obtained through specific breeding programs: the main purpose of such approach was to evaluate the influence of genetic background on these parameters. The total antioxidant capacity, the radical scavenging activity, the content of total phenolics, flavonoids, anthocyanins, vitamin C and folates were measured in the different strawberry extracts. Among the varieties studied, the cultivar Alba was chosen for its nutritional value and was used in the second part of the Thesis. The second aim of this project was to evaluate the effects of methanolic purified extracts from Alba cultivar on inflammatory status induced by E.Coli lipopolysaccharide (LPS) on two different cell lines, Human Dermal Fibroblasts (HDF) and RAW 264.7 macrophages. The cell viability, apoptosis rate and Reactive Oxygen Species (ROS) intracellular production were assessed. The protective role of strawberry extracts was estimated by the evaluation of the principal biomarkers related to inflammatory and oxidative stress and the activity of the principal antioxidant enzymes. Moreover, protein expression was evaluated to analyze and clarify the principal molecular pathways involved in strawberry and LPS mechanisms of action. Finally, the oxygen consumption rate related to mitochondria functionality was evaluated. The results obtained demonstrated that strawberry extracts had an anti-inflammatory effect on LPS treated cells, through a reduction of ROS and inflammatory and oxidative damages. Strawberry extracts also counteracted the inflammatory response increasing the antioxidant activities, through AMPK-related pathways. An improvement of mitochondria functionality was also demonstrated. The results obtained with this work highlight and confirm the potential health benefit of strawberry against inflammatory and oxidative stress.
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DI, VITTORI LUCIA. "Improving the sensorial and nutritional quality of strawberry fruits." Doctoral thesis, Università Politecnica delle Marche, 2018. http://hdl.handle.net/11566/253035.
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Negli ultimi decenni, il consumatore è sempre più attento agli aspetti salutari della dieta, ponendo quindi particolare attenzione alla qualità generale del prodotto, dal punto di vista agronomico e commerciale fino alla qualità sensoriale e nutrizionale. Queste caratteristiche sono molto variabili tra specie differenti di fragola, ma anche all’interno di diverse cultivar appartenenti alla stessa specie. Lo scopo di questo studio triennale è stato quello di valutare e selezionare nuovi genotipi di fragola dall’elevata qualità e valore nutrizionale.
I frutti di 51 genotipi di fragola derivanti da incroci interspecifici di Fragaria virginiana glauca con Fragaria x ananassa (F1), back-crossings (BC1, BC2 e BC3), varietà e selezioni di Fragaria x ananassa (Fxa) e da selezioni di Fragaria x ananassa per uso industriale (Fxa(Ind)) sono stati analizzati per parametri produttivi, sensoriali, qualitativi e nutrizionali.
Nel programma di back-crossing sviluppato in questo studio, la scelta dei migliori genotipi come parentali per le varie generazioni di backcrossing (BC1, BC2 e BC3) ha permesso di ottenere nell’ultima generazione selezioni ricche di sostanze antiossidanti, ma anche con un buon recupero delle caratteristiche produttive e un miglioramento delle proprietà sensoriali rispetto alle precedenti generazioni di incrocio. A questo punto del processo di miglioramento genetico, è possibile affermare che i caratteri per l’elevata quantità di sostanze antiossidanti sono stati stabilizzati nel BC3, anche con un piccolo aumento rispetto alle popolazioni di Fragaria x ananassa e F1. La produzione in questo gruppo non è lontana dalle esigenze commerciali: con un ulteriore aumento del peso del frutto mediante reincrocio con un genitore (Fragaria x ananassa) dalle elevate performance produttive, alcuni genotipi di BC3 hanno il potenziale per diventare cultivar commerciali.In the last few decades, the most knowledgeable consumer on the diet and its nutritional principles pays particular attention to the overall quality assessment, comprising the agronomic/commercial quality, the organoleptic quality and the nutritional quality. All those characteristics are very variable among different species, but also among different varieties within the same species. The aim of this triennial study is to select new genotypes of strawberries with high quality and nutritional value. Fruits of 51 strawberry selections from interspecific crossings of Fragaria virginiana glauca with Fragaria x ananassa (F1), back-crossings (BC1, BC2, BC3), varieties and advanced selections of Fragaria x ananassa (Fxa) and Fragaria x ananassa for industrial purpose (Ind) were analyzed for productive, sensorial, qualitative, and nutritional analyzes. In the back-crossing program developed in this study, the choice of best parental genotypes for the various backcrossing generations (BC1, BC2 and BC3) allowed to obtain in the last generation, selections rich in antioxidant substances but also with a good recovery of productive characteristics, and ameliorating sensorial properties in respect to the previous crossing generations. At this point of the breeding process, it is possible to affirm that characters for the high amount of antioxidant substances were stabilized at BC3, even with a small increase in respect to both Fragaria x ananassa and F1 populations. The production in this group is not far from commercial requirements: with further increasing of the fruit weight by backcrossing with a parent (Fragaria x ananassa) with high productive characteristics, some genotypes of BC3 have the potential to become commercial cultivars.
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Sinclair, Grant. "Influence of Colonization by Arbuscular Mycorrhizal Fungi and a Root Endophyte on Selected Strawberry Cultivars Under Salt Conditions." Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/26124.
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Two factorial greenhouse experiments were performed to determine the effects of four arbuscular mycorrhizal fungi (AMF) species (Glomus arenarium, Funneliformis caledonius, F. mosseae, and Rhizophagus irregularis) and a root endophyte (Piriformospora indica) on four ‘day-neutral’ strawberry (Fragaria × ananassa Duch.) cultivars (‘Albion’, ‘Charlotte’, ‘Mara des Bois’, and ‘Seascape’), and mixed-AMF species (R. irregularis + F. mosseae) on cv. ‘Seascape’, under salt conditions (0-200 mM NaCl). In its biomass, ‘Seascape’ was more tolerant to salinity than the other cultivars. Cultivars responded differently to fungal inoculation as to salinity. G. arenarium had a negative effect on plant growth and ‘Mara des Bois’ responded negatively to inoculation. Among the remaining inoculants and cultivars, fungal-symbiosis was beneficial to growth. R. irregularis alleviated the symptoms of salt stress and improved fruit quality to a higher degree than the other AMF species and the root endophyte. Our results support the use of bio-inoculants in salty horticultural areas.
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Cekic, Cetin. "Markers for positional cloning of seasonal flowering and runnering loci in Fragaria vesca L." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.326192.
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Arrepia, Carlos Manuel Araújo. "Estudo crítico do processo de fabrico de sorbet artesanal. Processo de descontaminação do morango." Master's thesis, ISA/UTL, 2012. http://hdl.handle.net/10400.5/5260.
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Mestrado em Engenharia Alimentar - Segurança e Qualidade Alimentar - Instituto Superior de AgronomiaThe present study took place at Santini, S.A., a home made ice cream company, during the transfer layout for the new installations. The main objective was to delineate the manufacturing process of Sorbet, to can determinate the critical points of preparation of fruit (in particular strawberries), in order to optimize the process conditions in the new factory. Initially, still at the old installations, was carried on, the manual mode of strawberry descontamination, where was analysed different binomials time and concentration of sodium hypochlorite, in order to understand those that are more effective. Once defined the best results, it was possible to improve the choosen conditions to the descontamination operation in automatic mode. At the new plant, already at the automatic wash fruit machine 90 ppm solution of sodium hypochlorite was used at different times. Following the temperature, pH solution and % loss of soluble solids (SST) on strawberry, were monitored. It was concluded that for the test conditions in manual mode, the largest logarithmic reduction for microorganisms at 30º C was 2,15 log cycles for the conditions of 81 ppm at 1 minute and 116 ppm at 5 minutes. The application in automatic mode of 90 ppm for 5 minutes proved to be effective in reducing the microbial load present in the strawberry. The SST of the strawberry is inversely proportional to the duration of decontamination unit operation.
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MacNeill, Morgan T. "Strawberries and Gut Health in Postmenopausal Women." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2072.
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The gut microbiota has been implicated in both health and disease. As such, diet is a significant determinant of gut health, whereby diet induced dysbiosis is associated with cardiometabolic risk. Interestingly, a higher proportion of Firmicutes and a lower proportion of Bacteroidetes are implicated in obesity. Strawberry polyphenols have been shown to reduce cardiovascular disease risk in addition to exhibiting prebiotic activity by increasing probiotic bacteria in the gut. Polyphenols have also been shown to reduce the ratio of Firmicutes to Bacteroidetes. Therefore, dietary modifications such as strawberry consumption may help improve health outcomes through the gut. The objective of this study was to analyze whether 13 g freeze dried strawberry powder (~1 cup/d fresh) consumption reduces the Firmicutes:Bacteroidetes ratio and increases microbial diversity and beneficial bacteria like Lactobacillus and Bifidobacterium. This study was a 5-week free-living diet intervention trial conducted at California Polytechnic State University, San Luis Obispo with expansion to the Eye Medical Center of Fresno. Participants (n=10) had a mean age of 60.5 ± 9.13 years and had a mean body weight of 74.71 ± 10.61 kg. The participants completed a 3-week washout before a 2-week diet intervention. Participants maintained their normal diet throughout the study while eliminating foods high in polyphenols and probiotics. Upon completion of the study, no significant differences were found for body weight (p=0.22) or BMI (p=0.26). Likewise, no significant differences were found for macronutrient, vitamin, or mineral intake except for sugar (p=0.03), vitamin B12 (p=0.03), and fruit (p=0.0014). Bacteria abundance and diversity were not found to be statistically significant following intervention. Since strawberry supplementation was not associated with a significant change in the relative abundance of bacteria with the dose and duration administered, a randomized controlled trial would better determine the effect of strawberry consumption on gut health.
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Harney, Marion. "Place-making for the imagination : Horace Walpole and Strawberry Hill." Thesis, University of Bath, 2011. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.545337.
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Strawberry Hill, the Gothic villa and associated landscape, seat of Horace Walpole (1717-97), is without doubt mandatory in any assessment of eighteenth-century British architecture, yet the reasons for its creation have never been adequately explained or fully understood. This thesis asserts, for the first time, that Walpole’s ideas which informed Strawberry Hill are inspired by theories that stimulate ‘The Pleasures of the Imagination’ as articulated in essays by Joseph Addison (1672-1719) published in the Spectator (1712). The thesis argues that Walpole’s reasons for choosing Gothic have been misunderstood and that he valued this ‘true’ style of British architecture for its associative and imaginative connotations and as a means of expressing historical interpretation through material objects. It affirms that Strawberry Hill expressed the idea that it was based on monastic foundations using architectural quotations from Gothic tombs, representing visual links to historical figures and events. The thesis, moreover, develops an argument as to how Walpole’s theories expressed in Anecdotes of Painting (1762-71) and The History of the Modern Taste in Gardening (1780) became manifest at Strawberry Hill. Avoiding the straightforward architectural description of previous texts, the thesis demonstrates Strawberry Hill to be a sequence of theatrical spaces playing with scale, colour and atmosphere, specifically designed to create surprise and wonder in order to stimulate the imagination. A series of sensory effects and moods, based on contemporary landscape theory, create a background to Walpole’s collection of cultural and historical artefacts – each ‘singular,’ ‘unique,’ or ‘rare’ - artfully displayed to produce their own narrative. Unlike previous studies, the villa and landscape are evaluated as an entity, a structured essay in associative, imaginative thought. Finally, the dissertation reconstructs Strawberry Hill as it existed in Horace Walpole’s time, leading the reader on an integrative virtual tour of buildings, gardens, emblematic models and associative inspirations.
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Rowley, Daniel R. "Season Extension of Strawberry and Raspberry Production Using High Tunnels." DigitalCommons@USU, 2010. https://digitalcommons.usu.edu/etd/716.
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High tunnels have been used successfully in many areas of the world to extend the growing season for numerous crops. However, very little research has been conducted to evaluate the season extension benefits offered by high tunnels to small fruit crops in high elevation growing areas such as the Intermountain West region of the United States. The use of high tunnels was investigated in North Logan, Utah (41.766 N latitude, 1405 m elevation, 119 freeze free days) to extend the growing season for both strawberries and raspberries. June-bearing `Chandler' strawberries in a fall-planted annual hill system were evaluated for early season production. High tunnels advanced spring strawberry production by approximately 3 weeks compared to field-grown plants. High tunnels were used for earlier planting and growth in a spring-planted day-neutral strawberry system. Day-neutral cultivars (`Albion', `Seascape', `Evie 2', and `Tribute') produced strawberries throughout the summer and into the fall with significantly higher yields from the high tunnel treatments than the field-grown plants. High tunnels also extended late-season strawberry production until mid-December. The floricane-fruiting red raspberry `Tulameen' was evaluated for early season production, and primocane-fruiting `Caroline' was evaluated for late season extension. High tunnels were unable to provide sufficient winter protection for the cold-tender `Tulameen' at this location. Results from late season extension indicated that high tunnels could extend late season raspberry production by as much as three weeks. However, peak yields for `Caroline' were before the first fall frost, and a later fruiting cultivar would be more suitable. In addition to research results, this thesis contains chapters on practical management considerations for commercial producers, and enterprise budgets to assist in evaluating the economic costs and returns of high tunnel strawberry and raspberry production.
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Rudh, Andreas. "Aposematism, Crypsis and Population Differentiation in the Strawberry Poison Frog." Doctoral thesis, Uppsala universitet, Zooekologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-175240.
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Evolutionary transitions between the two major predator avoidance strategies aposematism and crypsis are expected to be associated with changes in many important traits of animals. However, empirical studies on populations experiencing ongoing or recent transitions between these strategies are rare. This thesis investigates the co-evolution of traits among populations of the Strawberry poison frog D.pumilio in Bocas del Toro, Panama. I found that all investigated populations were genetically distinct but that colour and pattern did not correlate with genetic or geographic distance, which suggests that selection needs to be invoked to explain the observed variation. Based on the chromatic contrast between frog dorsal colour and the natural habitat substrates used by the frogs, the populations were defined as bright or dull coloured. I found that frogs from bright coloured populations were larger. This is expected if aposematism is enhanced by large signals while crypsis is enhanced by small size. Further, individuals from bright coloured populations had a coarser black dorsal pattern, which is expected if crypsis is impaired by a bold pattern. The importance of pattern coarseness was confirmed by an avian detection experiment showing that coarse patterned dark green prey were more easily detected than dark green prey without pattern or with fine pattern. I put forward the hypothesis that enhanced protection, gained by aposematism, may affect behaviours that influence dispersal and pairing patterns. Indeed, males from bright coloured populations displayed at more exposed sites and showed a tendency to be more explorative and aggressive. In summary, my results show that the bright and dull coloured populations most likely represent an aposematic and a cryptic strategy, respectively. Furthermore, I show that evolutionary changes between aposematism and crypsis can be associated with coevolution of both morphology and behaviour. I argue that this coevolution may increase the likelihood of both pre- and post-zygotic reproductive isolation. This is because greater phenotypic differences between populations increase the likelihood of selection against badly adapted migrants and hybrids with intermediate traits.
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Jin, Xiaolei. "Epidemiology and control of powdery mildew (Podosphaera aphanis) on strawberry." Thesis, University of Hertfordshire, 2016. http://hdl.handle.net/2299/17212.
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Strawberry powdery mildew, caused by Podosphaera aphanis, has the potential to cause over 20% yield loss, particularly where strawberries are grown under cover. A holistic approach to the control of strawberry powdery mildew (P. aphanis) is important, since the disease is never absent from the crop. The new disease assessment key was developed to assess strawberry powdery mildew (the old one is for assessing red blotches on leaves, See appendix 8). The results (Chapter 3) showed that the disease is present in the crop when new plants are bought in from a propagator, with 14% of strawberry crowns were infected by P. aphanis in July 2013 and 4% of the strawberry plants had symptoms of powdery mildew in pre-assessment of plants for the 2013 Si nutrient fertigation field experiment. Control measures used in one growing season reduced the disease carry-over, thus reducing the initial inoculum in the following season. The use of a late autumn fungicide spray and a fungicide spray before the plants were covered by fleece in spring reduced the number and maturity of overwintering chasmothecia, thus contributing to a reduction in initial inoculum. The use of silicon (Si) nutrient (foliar spray and root treatment) also suppressed strawberry powdery mildew development (Chapter 4). The results of Area Under Disease Progress Curve (AUDPC) and the rate of epidemic growth curve (r) in 2012 indicated that the high concentration of Si nutrient foliar spray inhibited (r = 0.002, AUDPC = 44) the epidemic build-up of P. aphanis better than the low concentration of Si nutrient (r = 0.012, AUDPC = 51) and untreated (r = 0.018, AUDPC = 70). The Si nutrient root treatment (AUDPC = 12.8) was better in inhibiting strawberry powdery mildew development than the Si nutrient foliar spray treatment. Moreover, the high concentration of Si nutrient foliar spray resulted in fewer chasmothecia compared to the untreated. Si nutrient foliar spray and root treatments increased the concentration of Si in the plants and produced physiological changes in the plants, including wax formation on the adaxial leaf surface, greater leaf thickness and cuticle layer and increased Brix0 value in plants, which all were associated with reduced disease incidence. The integrated use of all these control strategies suppresses disease development so that control is achieved with less use of conventional fungicides.
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Llorente, Garcia A. "Ethylene-mediated plant responses to severe water deficit in strawberry." Thesis, University of Reading, 2016. http://centaur.reading.ac.uk/67762/.
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The research described in this thesis focussed on the potential effect of ethylene produced under severe water deficit conditions (SWD) on the concentration of phenolic compounds in fruit and leaves of commercial strawberry (Fragaria x ananassa Duch.). An increased ethylene production rate was detected in green fruit and leaves at midday of the second day of wilting in response to SWD. The stress-induced rise in ethylene production was successfully inhibited by applications of aminoethoxyvinylglycine (AVG) and subsequently re-instated by 1-aminocyclopropane- 1-carboxylic acid (ACC) or replaced by abscisic acid (ABA) in fruits. Initially, fruit total ellagic acid concentration increased along with ethylene production but conclusive evidence for the causal role of ethylene in the accumulation of individual phenolics in fruit from the inhibition, re-instatement and replacement of the ethylene signal was not obtained. The quantitative expression of selected genes in leaves was investigated, and a significant reduction in the relative expression of FaACS1 (coding for ACC synthase), an increase in FaACO1, FaACO4 (coding for ACC oxidase) expression and no change on the expression FaPAL (coding for Phenylalanine ammonia lyase) was observed. Increased leaf ethylene production rate was likely due to increased expression of genes regulating ACC oxidase activity. However, no evidence was found from these genetic studies to confirm the role of stress-induced ethylene production in accumulation of phenolics in fruit or leaves.
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Saraswat, Dharmendra. "Geospatial technology applications to strawberry, grape and citrus production systems." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1174533489.
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Moročko, Inga. "Characterization of the strawberry pathogen Gnomonia fragariae, and biocontrol possibilities /." Uppsala : Dept. of Forest Mycology and Pathology, Swedish University of Agricultural Sciences, 2006. http://epsilon.slu.se/200671.pdf.
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Dodgson, Jolyon Lome Alexander. "Epidemiology and sustainable control of Podosphaera aphanis (strawberry powdery mildew)." Thesis, University of Hertfordshire, 2007. http://hdl.handle.net/2299/14356.
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Until recently strawberries grown in the United Kingdom were grown in open fields, the plants and fruit were exposed to the British weather. This resulted in a short 6 week harvest period where the fruit was often damaged by rain and infected by Botrytis cinerea. Strawberry growers started to use polythene tunnels to extend the cropping season, protect the fruit from rain damage and reduce the incidence of infection by B. cinerea. However the conditions produced by the polythene tunnels were ideal for the growth and development of Podosphaera aphanis (strawberry powdery mildew). Growers are now under pressure from the retailers to reduce the amount of fungicides that they use to control P. aphanis. The symptoms related to P. aphanis infection have been identified (leaf cupping, visible mycelium and red blotches) and a progression has been established: From the symptom progression two new s~ring methods for the identification of P. aphanis infections were developed wmch have greater relevance to current cultivation methods than the previous method. The source of initial inoculum for newly planted and established sites was identified. The inoculum was planted into new sites on the plants coming from the propagators and overwintering on plants within established sites. This was contrary to what the growers believed. They were basing their early season tunnel management on keeping the perceived air borne infection out of their tunnels. A rule based prediction system has been developed that has the potential to reduce the number of fungicide applications applied by the growers. The prediction system ensures that fungicide applications are not applied too close together. Potassium Bicarbonate has been shown to provide comparable control of P. aphanis to that achieved with Systhane (Myclobutanil). Significantly better control of P. aphanis was achieved using a new (at the time) product, Fortress (Quinoxyfen). There were significant differences in the resistance °to infection by P. aphanis displayed by different cultivars of strawberry. Elsanta, the cultivar favoured by the retailers was not one of the most resistant. Control of inoculum . already present on plants as they are being planted could be achieved by dipping the plant in Systhane. Growers are under considerable pressure from the retailers to reduce the amount of fungicides used to control P. aphanis. Growers could achieve this by implementing the recommendations made in this report.
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Themis, Matthew. "The role of acyl carrier protein in strawberry fruit ripening." Thesis, Durham University, 2000. http://etheses.dur.ac.uk/4520/.
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Strawberry (Fragaria ananassa) is an economically important soft fruit that is highly valued as a fresh product and flavouring. During ripening, strawberry fruits undergo a number of physiological changes affecting colour, texture and flavour. An understanding of these changes at the biochemical and molecular level will be important in developing strategies for enhancing the quality attributes of this fruit. A cDNA encoding a ripening- enhanced acyl carrier protein (RE-ACP) was previously isolated from strawberry fruit. AC? is an essential component of fatty acid synthesis in both plants and animals. The aims of this thesis were to isolate and characterise this and other members of the ACP multigene family expressed in strawberry fruit. Six closely related putative AC? cDNA isoforms were identified from strawberry. Two of these were obtained by screening a cDNA library from ripe fruit and three were obtained by a technique known as candidate fragment length polymorphism (CFLP) that utilised ACP gene-specific primers for AFLP-cDNA display. Northern analysis was not able to differentiate their expression but ACP was highly up-regulated in ripening fruit whereas low levels of expression were detected in other strawberry tissues, including achenes (seeds), expanding leaves and flowers. The RE-ACP was over-expressed in E. coli and the recombinant protein partially purified. The over-expressed protein had a M(_r) of 20kDa on SDS-PAGE and appeared to form a dimer. A genomic library was constructed from F. ananassa from which two different genomic clones closely related to RE-ACP were obtained. Promoter analysis indicated the presence of regulatory elements. The characterization of putative ACP cDNA and genomic clones, including the 5' upstream regions, is described and their possible role in strawberry fruit is discussed. Key words: Strawberry, fruit, ripening, gene expression, genomic, cDNA, fatty acid, acyl carrier protein, aroma, promoter.
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Al, Majathoub Mohannad. "Development of cryopreservation techniques for strawberry ((Fragaria x ananassa Duchesne)." Thesis, University of Derby, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.427603.
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Terry, Leon Alexander. "Natural disease resistance in strawberry fruit and Geraldton waxflower flowers." Thesis, Cranfield University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.274047.
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Sather, Jonathon J. "Viewpoint Optimization for Autonomous Strawberry Harvesting with Deep Reinforcement Learning." DigitalCommons@CalPoly, 2019. https://digitalcommons.calpoly.edu/theses/2008.
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Autonomous harvesting may provide a viable solution to mounting labor pressures in the United States' strawberry industry. However, due to bottlenecks in machine perception and economic viability, a profitable and commercially adopted strawberry harvesting system remains elusive. In this research, we explore the feasibility of using deep reinforcement learning to overcome these bottlenecks and develop a practical algorithm to address the sub-objective of viewpoint optimization, or the development of a control policy to direct a camera to favorable vantage points for autonomous harvesting. We evaluate the algorithm's performance in a custom, open-source simulated environment and observe affirmative results. Our trained agent yields 8.7 times higher returns than random actions and 8.8 percent faster exploration than our best baseline policy, which uses visual servoing. Visual investigation shows the agent is able to fixate on favorable viewpoints, despite having no explicit means to propagate information through time. Overall, we conclude that deep reinforcement learning is a promising area of research to advance the state of the art in autonomous strawberry harvesting.