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1
Zainal, Zamri. « Molecular biology of mango (Mangifera indica L.) fruit ripening ». Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.319645.
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2
Howpage, Daya, of Western Sydney Hawkesbury University, Faculty of Environmental Management and Agriculture et Centre for Horticulture and Plant Sciences. « Pollination biology of kiwifruit : influence of honey bees, Apis mellifera L, pollen parents and pistil structure ». THESIS_FEMA_HPS_Howpage_D.xml, 1999. http://handle.uws.edu.au:8081/1959.7/338.
Texte intégralRésumé :
The importance of European honey bees in improving fruit set, yield and fruit weight of kiwifruit on the central east coast of Australia was investigated. Field investigations were carried out using different bee saturations and different types of male pollen parents. These investigations confirmed the importance of honey bees in kiwifruit fruit set, yield and fruit weight. However, the results suggested that increasing bee activity alone may not increase pollination of kiwifruit by honey bees. Many factors need to be understood before introducing bees into the orchard. Bees were more effective during the early part of the flowering period, and bee activity varied according to the sex of the vine, planting design and the time of day. The type of male pollen parents also influenced fruit size and quality. Flowers pollinated by different pollen parents were assessed for pollen tube growth and histochemical changes. The resulting fruit were also examined for weight and seed numbers. Honey bees play the major role in the size and yield of kiwifruit, but the design of male vines, their age and type of male pollen may also contribute. The kiwifruit pistil also possesses important features that can be considered as adaptations to insect pollination.Doctor of Philosophy (PhD)
3
Populin, Francesca. « A systems biology approach to shed light on apple fruit development ». Doctoral thesis, Università degli studi di Padova, 2016. http://hdl.handle.net/11577/3424444.
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The research carried out and discussed in the present dissertation is positioned within the “TranscrApple” project (www.transcrapple.com), funded by the Provincia Autonoma di Trento (PAT) within the call “Grandi Progetti 2012”. The general objectives of this project, a significant part of which overlap with the present thesis, deal with the characterization, as wide as possible with the currently available technologies, of the transcriptional events, including those related to small RNAs (not discussed in the present dissertation), the metabolic changes, on a subset of primary and secondary metabolites, and hormones’ cross-talk, through a hormone profiling approach, occurring during apple fruit development.
The present thesis is organized in different chapters, mirroring the experimental and temporal rationale effectively pursued to develop the research herein described. The main objective of the present work deals not only with providing an overview of transcripts, metabolites and hormones and their variations during fruit development, but also with the setting up of technical and experimental solutions aimed at using the achieved information within an integrative platform, according to a “systems biology view”. In model species, all this kind of studies are extremely easier, thanks to the availability of ready-to-use bioinformatics tools that are not flexible enough to be used in other species. However, especially in tree crops, this approach is still far from being defined and standardized.
Chapter 1 introduces the theme “apple fruit development”, discussing the adoption of apple as a model system that, in the last decade, acquired great importance in terms of research among the fruit species thanks to the availability of its sequenced genome. After a brief introduction on the fundamental information available about the apple fruit growth, taking into account the technological and scientific points of view, few difficulties and gaps that hamper the achievement of a complete overview of the regulatory events coordinating the development and growth of the apple, are discussed in relation to the main quantitative and qualitative parameters characterizing the apple fruit production.
Chapter 2 enters into the apple fruit research area; the preliminary phase and the multiple validations (concerning different cultivars and seasons) of transcriptional markers during the main apple developmental stages were shown to be fundamental for choosing, on the base of the expression profiles of these genes, the most representative samples, among those collected also in different seasons. Several markers have been identified, validated and
employed, among those available from literature, allowing the selection of samples of cv Golden Delicious (herein considered as model) to be used for the subsequent transcriptional and metabolomic characterization carried out in the present research.
Chapter 3 deals with the hormonal profiling survey carried out along the apple fruit development for the first time in this species. The results have allowed not only the achievement of brand new data related to the major hormonal classes, to be employed for further researches, but also the clarification and/or confirmation of new hormonal interactions connected to the fruit development stage or the transition between stages. Moreover, the relevance of this study consists in having achieved, for the first time in apple, quantitative data of an important set of hormones concurrently on the same samples.
Chapter 4 concerns the survey on the metabolites and their variations during the apple fruit development. A complete overview of the changes of the different classes of metabolites (mainly sugars, organic acids, aminoacids and polyphenols) is given during the apple developmental cycle. The acquired data have been derived from the same samples already analyzed in the previous chapters, and will be integrated with data of diverse nature, such as the RNAseq.
Chapter 5 of the present thesis comes into the “system biology” area, initially among several technical difficulties, then partially solved, and gives an example of an alternative interpretation of the hormonal data put within a correlative network along with the RNAseq results achieved on the same samples.Le ricerche illustrate nella presente tesi di dottorato si collocano nell’ambito del progetto “TranscrApple” (www.transcrapple.com), finanziato dalla Provincia Autonoma di Trento (PAT) nell’ambito del bando Grandi Progetti 2012. Gli obiettivi generali del progetto, che in larga parte si accomunano a quelli della presente tesi, prevedono di caratterizzare, nella maniera più ampia possibile con le tecnologie attualmente disponibili, gli eventi transcrizionali, compresi quelli relativi agli small RNA (non affrontati nella presente tesi), metabolici, su un subset di metaboliti primari e secondari, e ormonali, tramite un approccio di hormone profiling, che si verificano durante lo sviluppo della mela. La presente tesi è organizzata in diversi capitoli, riflettendo la logica sperimentale e temporale effettivamente seguita per sviluppare le ricerche. Lo scopo principale del lavoro qui presentato è quello non solo di fornire una panoramica di informazioni su trascritti, ormoni e metaboliti e le loro variazioni durante lo sviluppo del frutto, ma anche di proporre delle soluzioni tecniche e sperimentali per poter collocare le informazioni acquisite in una piattaforma integrativa, secondo la logica della systems biology. Nelle specie modello, tutto ciò è fortemente facilitato dall’ampia disponibilità di tool bioinformatici pronti all’uso ma non sufficientemente flessibili per poter essere adattati ad altre specie. Tuttavia, soprattutto per quanto riguarda soprattutto le specie arboree da frutto, questo tipo di approccio è ancora lontano dell’essere definito e standardizzato. Il Capitolo 1 introduce l’argomento “sviluppo della mela” in relazione all’adozione del melo come specie arborea modello, in misura sempre più crescente soprattutto nell’ultimo decennio grazie anche alla disponibilità della sequenza del genoma. Dopo un excursus sulle principali e più recenti acquisizioni relative allo sviluppo del frutto del melo, vengono discusse alcune delle principali criticità e lacune, sia dal punto di vista tecnologico che scientifico, che impediscono una visione completa degli eventi regolativi che coordinano lo sviluppo e la crescita della mela, anche in relazioni ai principali parametri qualitativi e produttivi. Nel Capitolo 2 si inizia ad entrare nel merito delle ricerche, illustrando la fase preparativa di ricerca e validazione multipla (tra cultivar diverse e annate diverse) di marcatori trascrizionali delle fasi di sviluppo del frutto indirizzate alla corretta selezione di campioni rappresentativi in serie temporali raccolte in annate differenti. Sono stati identificati, validati ed utilizzati diversi marcatori fra quelli proposti in letteratura, consentendo la selezione dei campioni di cv Golden Delicious (qui usata come modello) da utilizzare nelle successive fasi di caratterizzazione trascrizionale e metabolomica condotte nelle tesi. Nel Capitolo 3 si affronta il primo importante studio dei profili ormonali durante lo sviluppo del frutto. I risultati acquisiti hanno consentito non solo di acquisire dati relativi alla maggior parte degli ormoni da poter utilizzare in ricerche future, ma anche di chiarire, confermare e/o ipotizzare delle interazioni ormonali in funzione dello stadio di sviluppo o della transizione tra stadi diversi. La peculiarità di questo studio consiste nell’aver ottenuto, per la prima volta nel melo, dati quantitativi di un set importante di ormoni a partire dagli stessi campioni. Il Capitolo 4 affronta invece la questione relativa ai metaboliti e alle loro variazioni nel corso dell’intero sviluppo del frutto. Viene in questo modo fornita una visione complessiva di come variano le diverse classi di metaboliti (principalmente zuccheri, acidi organici, amminoacidi e polifenoli) durante lo sviluppo. Anche in questo caso i dati sono stati acquisiti dagli stessi campioni utilizzati negli altri capitoli per le altre tipologie di analisi e potranno essere impiegati in ricerche successive, ad esempio, in una logica integrativa, insieme a dati trascrittomici di diversa natura, epigenetici, ecc. Nel Capitolo 5, finalmente, la tesi si addentra fra mille difficoltà tecniche, poi in parte superate, nella giungla della cosiddetta systems biology, fornendo un esempio di come i dati ormonali possono essere valorizzati attraverso la loro integrazione con i dati trascrittomici ottenuti tramite RNAseq a partire dagli stessi campioni.
4
Venturieri, Giorgini Augusto. « Floral biology of cupuassu (Theobroma grandiflorum (Willdenow ex Sprengel) Schumann) ». Thesis, University of Reading, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386982.
Texte intégralRésumé :
Cupuassu (Theobroma grandiflorum), one of the most profitable crops of Amazonia, is now attracting world-wide attention as an exotic fruit, used in juices, ice cream and sweets. It is a shade tolerant tree that can be grown as a component of agroforestry systems. Nevertheless it is still a wild species and little is known about its biology. Floral biology of cupuassu was studied in Belem-Brazil during 2 floweringfruiting seasons between June 1991 and December 1993. Flowering occurs in the drier period of the year. Flowers commence opening at any time of the day, but open fully at the end of afternoon. The anthers dehisce and the stigmas are receptive as soon as the flowers are fully open. Stigmas remain receptive until 10:00 am the following day. Throughout this period, the pollen grains remain viable. The flowers have a complex morphology which favours allogamy. The species is also self-incompatible. Experimental pollinations, using compatible pollen grains, have shown that a flower which receives 60 compatible pollen grains has 20% probability of setting fruit; a flower which receives more than 400 pollen grains always sets fruit. However, only around 2% of naturally pollinated flowers receive more than 60 pollen grains. A stingless bee, Plebeia minima, is considered an effective pollinator of cupuassu. Another stingless bee, Trigonisca pediculana, also visits cupuassu flowers. Both bees are small insects, which are unlikely to fly very far. Ants (Wasmannia sp.) and weevils (Baris sp.) were considered secondary pollinators, unlikely to promote effective pollinationsFruits mature during the wet period of the year, approximately 5.5 months after the flowers open. The limited and irregular fruit set is probably caused by scarcity of pollinators. The transformation of cupuassu to a plantation crop will therefore require conditions which favour natural pollinators and their access to receptive and compatible flowers
5
Ponappa, Tilak. « Investigations into the role of polyamines in strawberry fruit development / ». The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487844105974317.
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6
Finger, Fernando Luíz. « The role of NADP+[superscript]-malic enzyme in tomato fruit / ». The Ohio State University, 1993. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487847761307751.
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7
Kilaru, Aruna. « Changes in Avocado Transcriptome During Fruit Maturation ». Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/4774.
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8
Hobololo, Vuyisile Lanele. « Field biology and identification of fruit flies in the Western Cape Province ». Thesis, Stellenbosch : Stellenbosch University, 2004. http://hdl.handle.net/10019.1/49966.
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Thesis (MSc)--University of Stellenbosch, 2004.ENGLISH ABSTRACT: Two fruit fly species, Ceratitis capitata (Wiedemann) and C. rosa (Karsch) (Diptera: Tephritidae) are known to attack deciduous fruit in the Western Cape Province of South Africa. The relative abundance of these two pests was studied in different kinds of fruit throughout the year. To facilitate field monitoring, using the immature stages, morphological differences between larval instars of C. capitata and C. rosa were investigated. Morphological characters of the larvae, such as the spiracles (anterior and posterior), mouth hooks and oral ridges were used. Many of these characters are only suitable to distinguish between the second and third instar larvae as these structures are not yet developed in the first instar larvae. Anterior spiracles were examined in terms of the number of tubules (papillae) and size or shape of the felt chambers. The number of papillae in both species was similar in the second and third instar larvae, but differed between the larvae of the two species (8-10 for C. capitata and 10-13 for C. rosa). In both species the felt chambers of the second instar larvae were narrow and elongate whilst those of the third instar larvae were broad and short. The major difference between the mouthhooks of the two tephritids was the presence of a sub-apical tooth in the third instar larva of C. rosa, being absent in the third instar of C. capitata. For the morphometric study, both laboratory-reared and field-collected specimens were examined. Measurements of the body dimensions (length and width) and various parts of the cephalopharyngeal skeleton (CPS) (mandible base, mandible length and distance between the tip and notch) were recorded in all three instars of both C. capitata and C. rosa. The data were analysed using finite mixture analysis (FMA-N1) and Levene's test was used to test for homogeneity of variances. The results of these analyses were used to estimate the frequency distributions of the larval measurements. In some cases overlaps in distributions were evident and were resolved using the same program, finite mixture analysis (FMA-N1), based on the probability of the overlapping measurements belonging to the designated instar (i.e. the one with highest probability). Determination of growth ratios suggested an approximate conformation to Dyar's rule thereby disputing the possibility of any hidden instar. However, in most cases measurements of the field samples did not conform to Dyar's rule. For the larval instars of C. capitata and C. rosa with overlapping morphological features, the morphometric approach as a distinguishing tool was demonstrated. In the field survey, the relative abundance of C. rosa at all experimental sites was very low in both orchards and adjacent vines. This suggested that this pest was either not a threat in these sites (crops) or the monitoring procedures applied, should be revised. Trap catches indicated high levels of infestation by C. capitata on some sites and low infestation levels at others. On the site with the highest population levels, activity peaks in the orchards did not co-incide with those in the adjacent vineyards. This suggested that these vineyards could be alternative hosts for fruit fly after the fruit in the orchards have been harvested. Forced oviposition (in vitro) studies indicated that Colombard (grown in Simonsvlei) was the most suitable host for survival of C. capitata. Other wine grape cultivars such as Chardonnay were also suitable for the total larval development of C. capitata.
AFRIKAANSE OPSOMMING: Twee spesies van die vrugtevlieg, Ceratitis capitata (Wiedemann) en C. rosa (Karsch) (Diptera: Tephritidae), val sagtevrugte in die Wes Kaap Provinsie van Suid- Afrika aan. Die groot hoeveelheid van hierdie twee plae op verskillende soorte vrugte is regdeur die jaar bestudeer. Voordat enige insekplaag gemonitor kan word, is dit belangrik dat die identiteit van die besondere plaag, insluitend sy onvolwasse stadiums, bekend moet wees. In hierdie studie word die morfologiese verskille tussen die larwe stadiums van C. capitata en C. rosa ondersoek. Kenmerke soos die spirakels (voor en agter), mondhake en mondriwwe is gebruik. Baie van hierdie morfologiese kenmerke kan net gebruik word om te onderskei tussen larwes in die tweede en derde stadiums omdat hierdie strukture nog nie in die eerste stadium ontwikkel is nie. Die voorste spirakels is ondersoek in terme van die aantal tubules (papillae) en die grootte en vorm van die vilt kamers. In beide spesies is die aantal papillae dieselfde vir die tweede en derde larwe stadiums, maar daar was en verskil tussen die larwes van die twee spesies (8-10 vir C. capitata en 10-13 vir C. rosa). In altwee spesies was die viIt kamers van die twee stadium larwes sma I en verleng, terwyl dit in die derde stadium larwes breed en kort was. Die hoof verskil tussen die mondhake van die twee vrugtevliee was die aanwesigheid van die subapikale tand in die derde stadium larwe van C. rosa, terwyl dit afwesig is in die derde stadium van C. capitata. Vir die morfometriese studie is voorbeelde van laboratorium geteelde vrugtevliee, asook vilee wat in die veld gevind is, ondersoek. Die liggaamsafmetings (Iengte en breedte) is gemeet asook die skelet (mandibel basis, mandibel lengte en die afstand tussen die punt en die kerf) in al drie stadiums van C. capitata en C. rosa. Die data is ontleed deur middel van eindige mengsel analise (FMA-N1) en Levene se toets is gebruik om vir homogeniteit en variansies te toets. Die resultate van die ontleding is gebruik om die frekwensie verspreiding van die larwale metings te skat. In sommige gevalle was daar oorvleueling en dit is opgelos met die gebruik van dieselfde program FMA-N1 baseer op die moontlikheid dat die metings wat oorvleuel, aan die aangeduide stadium (d.w.s die een met die hoogste waarskynlikheid) behoort. Die vasstelling van groei ratios dui aan dat dit naasteby ooreenstem met Dyar se reel en dus die moontlikheid van 'n versteekte stadium betwis. Maar in die meeste gevalle stem die veldmonsters nie ooreen met Dyar se reel nie. Die feit dat die morfometriese benadering die verrnoe het om larwale monsters met oorvleuelende morfologiese kenmerke, beteken dat dit kwalifiseer as In instrument om tussen die larwe stadiums van C. capitata en C. rosa te onderskei. Baie min C. rosa is in vrugteboorde en in nabygelee wingerde gevind. Dit dui of dat die plaag nie 'n bedreiging vir die vrugte inhou nie, of dat die monitor prosedures hersien moet word. Lokvalle dui aan dat daar 'n hoe vlak van infestasie van C. capitata in sommige gebeide is en In lae vlak in ander. Op die plek met die hoogste bevolking van vrugtevliee het die aktiwiteit in die boorde nie ooreengestem met die aktiwiteit in die nabygelee wingerde nie. Dit dui aan dat hierdie wingerde 'n alternatiewe blyplek bied aan die vrugtevliee nadat die vrugte in die boorde geoes is. Gedwonge oviposisie studies dui aan dat C. capitata die beste kan oorleef in Colombard (gekweek te Simonsvlei). Ander wyndruif kultivars is ook geskik vir die ontwikkeling tot by die laaste larwe stadium van C. capitata.
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Michael, Karen. « Clarification of basal relationships in Rubus (Rosaceae) and the origin of Rubus chamaemorus ». TopSCHOLAR®, 2006. http://digitalcommons.wku.edu/theses/250.
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Determination of phylogenetic relationships among ancestral species of Rubus has been elusive. Most Rubus species (including blackberries and raspberries), representing nine of the 12 subgenera, occur in a large, well supported clade named 'A' for reference). The remaining nine species are excluded from this group and represent three subgenera: subg. Anoplobatus (R. bartonianus, R. deliciosus, R. neomexicanus, R. odoratus, R. parviflorus, R. trilobus), subg. Chamaemorus (R. chamaemorus), and subg. Dalibarda (R. lasiococcus, R.pedatus). In addition, Rubus dalibarda L. is often treated in its own monotypic genus as Dalibarda repens L. Phylogenetic analyses of DNA sequence data from chloroplast regions and the nuclear ribosomal DNA internal transcribed spacer ITS 1 - 5.8S - ITS 2; ITS) region have not resolved basal relationships in Rubus and the position of Dalibarda repens has varied from being the sister group to Rubus to nested within it. However, monophyly of American subg. Anoplobatus species is supported by both genomic regions. Our goal was to clarify ancestral relationships, investigate the position of Dalibarda repens relative to Rubus, and examine the origin of the circumboreal, octoploid species R. chamaemorus using sequence data from one additional chloroplast DNA region, trnS-trnG, and the singlecopy nuclear gene Granule-Bound Starch Synthase (GBSSI-1). Parsimony analyses of trnS-trnG sequences indicate a basal trichotomy, while R.chamaemorus is strongly supported as sister to R. pedatus. A combined cpDNA (trnS-trnG and three other regions) parsimony analysis indicates that subg. Anoplobatus is sister to clade A, and strongly supports Dalibarda repens as sister to R. lasiococcus. This suggests that Dalibarda repens be classified as R. dalibarda consistent with Linnaeus (1762) and Focke (1910). Parsimony analyses of GBSSI-1 sequences result in a large polytomy and do not recover clade A. The presence of three (GBSSI-la, GBSSI-1 (3 and GBSSI-ly) putative forms of the gene is observed. However, separate parsimony analysis of GBSSIly sequences demonstrates strong support for clade A and the monophyly of ubg. Anoplobatus. In this analysis, two different alleles are present in R. chamaemorus; one occurs outside clade A (sister to R. lasiococcus) and the other nests within clade A (sister to R. arcticus). Thus these data suggest that R. chamaemorus may be an ancient allopolyploid. The phylogenetic position of Dalibarda repens relative to Rubus cannot be resolved by existing GBSSI-1 data.
10
Hale, Frank Allen. « Fruit quality sampling, record keeping, and packing line data in Ohio apple orchards / ». The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487688507503423.
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Srivastava, Pawan. « Studies on the electrochemical analysis of calcium and calcium binding in apple fruit / ». The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487864986609625.
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Clevenger, Josh. « Metabolic and genomic analysis of elongated fruit shape in tomato (Solanum lycopersicum) ». The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1354313370.
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Wunnachit, Wijit. « Floral biology of cashew (Anacardium occidentale L.) in relation to pollination and fruit set ». Adelaide Thesis (Ph.D.) -- University of Adelaide, 1991. http://hdl.handle.net/2440/21622.
Texte intégralRésumé :
Title page, contents and abstract only. The complete thesis in print form is available from the University Library.Thesis (Ph.D.)--University of Adelaide, Dept. of Horticulture, Viticulture and Oenology, 1991
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Wunnachit, Wijit. « Floral biology of cashew (Anacardium occidentale L.) in relation to pollination and fruit set ». Thesis, Adelaide Thesis (Ph.D.) -- University of Adelaide, 1991. http://hdl.handle.net/2440/21622.
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Howpage, Daya. « Pollination biology of kiwifruit : influence of honey bees, Apis mellifera L, pollen parents and pistil structure ». Thesis, Richmond, N.S.W. : Centre for Horticulture and Plant Sciences, University of Western Sydney, Hawkesbury, 1999. http://handle.uws.edu.au:8081/1959.7/338.
Texte intégralRésumé :
The importance of European honey bees in improving fruit set, yield and fruit weight of kiwifruit on the central east coast of Australia was investigated. Field investigations were carried out using different bee saturations and different types of male pollen parents. These investigations confirmed the importance of honey bees in kiwifruit fruit set, yield and fruit weight. However, the results suggested that increasing bee activity alone may not increase pollination of kiwifruit by honey bees. Many factors need to be understood before introducing bees into the orchard. Bees were more effective during the early part of the flowering period, and bee activity varied according to the sex of the vine, planting design and the time of day. The type of male pollen parents also influenced fruit size and quality. Flowers pollinated by different pollen parents were assessed for pollen tube growth and histochemical changes. The resulting fruit were also examined for weight and seed numbers. Honey bees play the major role in the size and yield of kiwifruit, but the design of male vines, their age and type of male pollen may also contribute. The kiwifruit pistil also possesses important features that can be considered as adaptations to insect pollination.
16
Sung, Ha-Jung, et Aruna Kilaru. « Identification of Acyltransferases Associated with Oil Accumulation in Avocado Fruit ». Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/4806.
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In avocado, an economically important crop, fruits can store up to 70 % oil in the form of triacylglycerols (TAGs). While TAG synthesis in seed tissues mostly depends on an acyl CoA-dependent enzyme, diacylglycerol (DAG) acyltransferase (DGAT) to catalyze the conversion of DAG to TAG, the enzymes involved in non-seed tissues remains to be elucidated. Recent studies on oil palm suggested participation of an acyl-CoA-independent enzyme, phospholipid:diacylglycerol acyltransferase (PDAT), in TAG synthesis. Our research focuses on identifying acyltransferases involved in oil accumulation in mesocarp tissues of avocado. Furthermore, in ‘Hass’ avocado, where 20-60 % of the fruit are phenotypically small, even under favorable conditions, we are interested in determining the association between oil accumulation and fruit size. To this extent, we quantified gene expression levels for DGAT 1 and 2 and PDAT and the rate of oil accumulation in developing mesocarp (oilrich) and seed (non-oil rich) tissues of phenotypically 'small' and 'normal' fruits, using real-time PCR and gas chromatography, respectively. Candidate acyltransferase genes, highly expressed in mesocarp but not in seed, will be cloned and characterized. Understanding TAG synthesis in non-seed tissues will allow us to develop genetic tools necessary for generating bioenergy-rich crops.
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Sung, Ha-Jung, et Aruna Kilaru. « Identification of Acyltransferases Associated with Triacylglycerol Biosynthesis in Avocado Fruit ». Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etsu-works/4865.
Texte intégralRésumé :
Modern society’s demand for oil has resulted in depletion of resources and caused higher oil prices. Therefore, natural oil resources of plants are gaining the spotlight and are expected to increase twice that of current use by 2030. Plants are able to accumulate up to 90% oil by dry weight in the form of triacylglycerol (TAG) and it is derived from fleshy part of the fruits, such as mesocarp of oil palm, avocado, and olive. In seed tissues, an acyl CoA-dependent enzyme, diacylglycerol acyltransferase (DGAT) participates in conversion of diacylglycerol (DAG) to TAG. However, TAG can also be formed by an acyl CoA- independent enzyme, phospholipid:diacylglycerol acyltransferase (PDAT). Avocados (Persea americana) store up to ~70% oil in mesocarp and I am interested in identifying the acyltransferase involved in oil biosynthesis in mesocarp tissues. Based on the transcriptome data available, I hypothesize that unlike in seeds, both DGAT and PDAT are associated with TAG biosynthesis in developing mesocarp of avocado. To test this hypothesis, I will determine 1) TAG content and composition and 2) expression levels for DGAT and PDAT genes in mesocarp and seed tissues of five stages of developing fruits of avocado (n=5). Total lipids will be extracted by isopropanol-chloroform method and analyzed for composition as methyl esters on GC-FID. Total RNA, for expression analysis, will be extracted by Trizol method and analyzed with gene-specific primers by real-time PCR. Statistical significance in change in oil content in association with gene expression during fruit development between mesocarp and seed tissues will be analyzed by ANOVA repeated measures. Comparison of temporal gene expression pattern of oil accumulation mesocarp, to that of seed, will allow us to differentiate the acyltransferase(s) specifically associated with TAG biosynthesis. The proposed research work will take the field of plant lipid biochemistry a step forward in understanding TAG synthesis in fruit tissue. Specifically, I will be able to clearly demonstrate the association of a particular acyltransferase to increasing lipid content in a non-seed (mesocarp) tissue. Understanding differences in oil regulation of a basal angiosperm (avocado) in relation to a monocot (oil palm) and a dicot (olive) also will provide additional insights into fundamental changes in TAG biosynthesis during the evolution of flowering plants. My research is part of a global project that includes a group in California, Florida and Israel. Data generated from my proposed work will be used to develop a joint Binational Agricultural and Research proposal. Therefore, my research work will subsequently contribute to development of ways to manipulation of extent and timing of oil accumulationa direct benefit to avocado growers. Furthermore, this study will be a pivotal step to understanding TAG synthesis that will lead to bioenergy crop.
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Kim, Young Soo. « Behavioral studies of learning mechanism with three different subjects : Honey Bee, Fruit Fly, and Flesh Fly / ». The Ohio State University, 2000. http://rave.ohiolink.edu/etdc/view?acc_num=osu1488193665236633.
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Frost, David Jay. « The influence of calcium deficiency on embryo and fruit development of Cucumis sativus L. / ». The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487331541709367.
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Chen, Lin. « Probing roles of ethylene in leaf gas exchange, growth and development using ACC-deaminase containing rhizobacteria and 1-methylcyclopropene (1-MCP) ». Thesis, Lancaster University, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.654943.
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Muñiz, Ortiz Jorge G. « Toxicogenetic Studies in Drosophila : Using Fruit Flies to Study Arsenic Toxicity ». University of Cincinnati / OhioLINK, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1231776077.
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Irving, Andrew David. « General methods for large biological networks applied to fruit fly models ». Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/general-methods-for-large-biological-networks-applied-to-fruit-fly-models(5eb3812e-f2dc-488b-bba4-fa0f094d4776).html.
Texte intégralRésumé :
A key part of a fruit fly's development is the formation of segmentsin its body. These structures are built by the protein forms of so-called segment polarity (SP) genes. It is the asymmetric expression of SP genes which creates the fruit-fly's segmental structure. The SP genes and their products (e.g. proteins) can be said to form a system which is self-regulating, i.e. genes are used to make proteins and, in turn, proteins are used to turn genes on or off. How this system achieves stable asymmetry of this kind is mathematically interesting as it can be thought of in a different way - multiple symmetries in the same system. This is unusual and we attempt to explain how it is possible using a mathematical model constructed by von Dassow et al. When trying to understand a biological system of this kind, there are two main approaches - reductionist and holistic. We try to show that they are not mutually exclusive - we look at the whole system but reduce what is meant by the whole. For example, von Dassow's model is large scale and, using it as a template, we show that a similar (but smaller) model inherits its properties. Smaller models can be made by short-handing the translation process (through which RNA is used to make protein) wherever an SP gene has a unique protein form. Our data indicates that the simultaneous wild-type expression of key SP genes (engrailed and wingless) takes place only when cumulative regulation of the wingless gene by two SP proteins is weak. The absence of this regulation would explain coexistence of multiple mathematical symmetries in one system (representative of genetic asymmetry) as it acts like a division between them. In this way, the system itself can be thought to divide into two independent sub-systems which can be treated separately.
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Ottens, Kristina Jane. « Ecological and biogeographical patterns associated with genetic differentiation in a diverse genus of Neotropical fruit flies ». Thesis, University of Iowa, 2015. https://ir.uiowa.edu/etd/1716.
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Understanding the processes that generate biodiversity is a major goal of evolutionary biology. The ultimate cause of biodiversity is the evolution of barriers to gene flow between populations of organisms, but the proximate mechanisms are often more complex. I am interested in disentangling the roles of geographic isolation and ecological selection in the diversification of a species-rich genus of tropical tephritid fruit flies. Blepharoneura are highly specialized and host specific flies; most species specialize on a single plant host and flower sex although multiple species may exploit the same resource. At one location in Peru, two plant species (two sexes - four plant niches) are host to 14 Blepharoneura species. Phylogenetic analyses of mitochondrial DNA sequences reveal that some species may be diverging as a result of shifts to new host plants (suggesting possible ecological selection acting in speciation), while other species show an apparent pattern of geographic divergence in addition to or without host shifts. To further investigate these ecological and geographic signals underlying the history of Blepharoneura speciation, more rapidly evolving molecular markers are required. Here, I use microsatellites to address this question for seven Blepharoneura species (sp1, sp4, sp8, sp10, sp21, sp28, and sp30) characterized by differing patterns of host-plant use and geographic distribution. Microsatellite data indicates patterns of ecological divergence associated with host use in at least five species (sp1, sp4, sp10, sp21, sp30) and patterns of geographic divergence in all seven species.
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AraÃjo, Jackson de Lima. « Arthropods and attributes soil microbiology in fruit trees en Vale do Curu-CE, Brasil ». Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=13481.
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A major concern related to agricultural management systems used by the man lies on the effects on biological processes in the soil, whose action within ecosystems aiming at the farm, modifies the intensity of these processes under use of techniques that exclusively aim to maximize crop yield. One of the challenges of research in soil biology is precisely understand the impacts on the complex interactions of all soil organisms at the community level by the management that are critical in maintaining soil quality. The objective of this work was to evaluate the influence of management practices on fruit trees (mango, guava and coconut trees) in the composition and distribution of soil arthropods (edaphic macrofauna, mesofauna) and on microbial biomass, the activity and interaction with the chemical, physical and environmental attributes. The study of soil arthropods began in July 2013 and followed until May 2014, with measurements at four periods. Microbiological soil activities were evaluated by the determination of microbial soil properties (RBS, CBM, NBM, NBM / N, qCO2 and qMIC). It was found that the soil arthropods were sensitive to changes arising from different soil tillage systems, allowing it to be used as an important tool to apply as bio-indicators of the quality of edaphic system. The system with guava cultivation proved to be unstable over time in relation to the structure of the community of soil arthropods. The system with coconut tree cultivation allows for better soil quality, increase in abundance and species richness of invertebrate macrofauna. The microbial biomass carbon (MBC), microbial biomass nitrogen (NBM) and the metabolic quotient (qCO2) were the main microbiological soil properties responsible for identifying dissimilarities between areas. Correlations between microbiological and faunal characteristics of the soil were low with significant correlations only between Collembola, NBM and NBM / N.Uma das grandes preocupaÃÃes relacionadas aos sistemas de manejo agrÃcola adotado pelo homem reside nos efeitos sobre os processos biolÃgicos que ocorrem no solo, cuja aÃÃo dentro dos ecossistemas visando à exploraÃÃo agrÃcola, modifica a intensidade desses processos em virtude do emprego de prÃticas que objetivam exclusivamente a maximizaÃÃo da produÃÃo vegetal. Um dos desafios da pesquisa em biologia do solo à justamente entender os impactos do manejo sobre as complexas interaÃÃes de todos os organismos edÃficos ao nÃvel de comunidade que sÃo fundamentais na manutenÃÃo da qualidade do solo. Objetivou-se avaliar a influÃncia dos manejos em cultivos de fruteiras (mangueira, goiabeira e coqueiro) na composiÃÃo e distribuiÃÃo dos artrÃpodes de solo (mesofauna e macrofauna edÃfica) e sobre a biomassa microbiana, sua atividade e interaÃÃo com os atributos quÃmicos, fÃsicos e ambientais. O estudo dos artrÃpodes edÃficos teve inÃcio em julho de 2013 e seguiu atà maio de 2014, com coletas realizadas em quatro perÃodos. As atividades microbiolÃgicas do solo foram avaliadas mediante as determinaÃÃes dos atributos microbianos do solo (RBS, CBM, NBM, NBM/N, qCO2 e qMIC). Constatou-se que os artrÃpodes de solo mostraram-se sensÃveis as alteraÃÃes ocasionadas pelos sistemas de manejos do solo, possibilitando a sua indicaÃÃo como importante ferramenta para aplicar-se como bioindicadores da qualidade do sistema edÃfico. O sistema com cultivo de goiabeiras mostrou-se instÃvel ao longo do tempo em relaÃÃo à estrutura da comunidade dos artrÃpodes de solo. O sistema com cultivo de coqueiros propicia melhores caracterÃsticas do solo e aumento na abundÃncia e riqueza de espÃcies da macrofauna invertebrada. O carbono da biomassa microbiana (CBM), nitrogÃnio da biomassa microbiana (NBM) e o quociente metabÃlico (qCO2), foram os principais atributos microbiolÃgicos do solo responsÃveis por identificar dissimilaridades entre as Ãreas. CorrelaÃÃes entre as variÃveis microbiolÃgicas e faunÃsticas do solo foram baixas, com correlaÃÃes significativas somente entre Collembola, NBM e NBM/N.
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Sung, Ha-Jung, et Aruna Kilaru. « Identification of Key Genes Associated with Triacylglycerol Biosynthesis in Avocado Fruit ». Digital Commons @ East Tennessee State University, 2013. https://dc.etsu.edu/etsu-works/4861.
Texte intégralRésumé :
A variety of plants are natural resources for oil and are capable of synthesizing and storing up to 90% oil (dry weight) in the form of triacylglycerols (TAGs). TAGs are commonly used as vegetable oils of which, >35% is derived from fleshy part of the fruits, such as mesocarp of oil palm, avocado, and olive. Studies on TAG synthesis in seed tissues mostly implicated an acyl CoA-dependent enzyme, diacylglycerol (DAG) acyltransferase (DGAT) to catalyze the conversion of DAG to TAG. However, recent studies on Arabidopsis and oil palm suggested participation of a phospholipid:diacylglycerol acyltransferase (PDAT), which is an acyl-CoA-independent enzyme. In avocados, which store up to 70% oil in mesocarp, I hypothesize that both DGAT and PDAT are likely involved in TAG synthesis. To test the hypothesis, I determined TAG content and composition by gas chromatography (GC) and expression levels of DGAT and PDAT genes by real-time PCR, in developing mesocarp. These data will be compared to that of seed tissues of avocado to associate gene expression levels with changes in oil accumulation. Future studies on cloning and characterization of these potential acyltransferase genes involved in TAG synthesis will allow us to develop genetic tools that may increase oil yield; a step towards meeting the consumption demand for oil that is expected to almost double by 2030.
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Kilaru, Aruna, Xia Cao, Ha-Jung Sung, Parker Dabbs, Mahbubur Md Rahman, Keithanne Mockaitis et John B. Ohlrogge. « Developmental Profiles Of The Avocado Fruit Transcriptome During Oil Accumulation ». Digital Commons @ East Tennessee State University, 2014. https://dc.etsu.edu/etsu-works/4805.
Texte intégralRésumé :
Unlike most other fruits that accumulate oil in seed tissues, avocado stores large amounts of oil in the form of triacylglycerol (TAG) in its mesocarp tissue. The regulation of TAG biosynthetic pathways in such nonseed tissues is poorly understood. RNA-Seq was used to identify the transcriptional networks underlying TAG biosynthesis in developing mesocarp of avocado. Deep transcriptional profiling studies revealed that several transcripts were differentially represented between the early and late developmental stages of mesocarp. The temporal expression pattern of transcripts associated with fatty acid biosynthesis in plastid coincided with increasing oil content. Furthermore, except for the transcripts that likely encode enzymes involved in the terminal step in TAG synthesis, others involved in TAG assembly in the endoplasmic reticulum were poorly expressed. This pattern of higher expression for genes involved in fatty acid synthesis but not TAG assembly was similar to previously observed pattern in other seed and nonseed tissues. Comparative analysis of transcript levels for about 1500 transcription factors, across different species and oil-storing tissues, also revealed that WRINKLED1 may be highly conserved across species but transcriptional regulation of oil biosynthesis, includes distinct tissue-specific features. In conclusion, while the biochemical pathways for oil biosynthesis in nonseed tissue are highly similar to that of seed tissues, certain distinctive modes of regulation of fatty acid biosynthesis and TAG assembly likely occur in oil-rich nonseed tissues.
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Kwasniewska, Agnieszka. « Field and laboratory studies on the effects of host fruit volatiles on «Rhagoletis mendax» (Diptera : Tephritidae) adults ». Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=66956.
Texte intégralRésumé :
I examined olfactory responses of the blueberry maggot fly Rhagoletis mendax Curran towards organic volatile compounds extracted from host fruit, in both field and laboratory experiments. First, I investigated the effects of eight volatile treatments on the capture rate of adult flies, in Saint-Chrysostome, QC. A second study focused on testing the attractiveness of the same volatile treatments in wind tunnel bioassays. I also evaluated the effect of experience, sex and population on the olfactory response of these flies. Ammonium acetate was one of the more effective lures in field experiments during the early season. The treatment blend of terpenes and alcohols had the highest fly capture rate in early and late season but it did not differ significantly from ammonium acetate. Ammonium acetate elicited the strongest response in wind tunnel bioassays, followed by a blend of aldehydes and alcohols. Nova Scotia flies had an overall higher response to treatments than the Quebec population and male flies exhibited a higher flight frequency. Experienced flies were also less stimulated by the treatments than naive flies. This research has provided an initial step in identification of attractive host fruit volatiles to R. mendax adults, supporting the hypothesis that volatile host blends of specific compounds are attractive to the insect. It is also suggested that future experiments use either male or female, naive flies from the same geographical location.J'ai examiné les réponses olfactives de la mouche de bleuet, Rhagoletis mendax Curran, face à des composés organiques volatils extraits de bleuets, lors d'expériences de terrain et de laboratoire. Premièrement, j'ai étudié les effets de huit traitements de produits chimiques volatiles distincts sur les niveaux de capture de mouches adultes, à Saint-Chrysostome, QC. Une deuxième étude a concernait le potentiel d'attraction de ces mêmes traitements lors d'essais biologiques en tunnel de vol. J'ai aussi évalué l'effet de l'expérience, du sexe et de la population sur la réponse olfactive de ces mouches. L'acétate d'ammonium a été l'appât le plus efficace lors des expériences de terrain en début de saison. Le mélange de terpènes et d'alcools a procuré le niveau de capture de mouche le plus élevé en début et en fin de saison, mais n'a pas manifesté de différences significatives face à l'acétate d'ammonium. L'acétate d'ammonium a suscité la plus forte réponse dans les essais biologiques en tunnel de vol, suivie par un mélange d'aldéhydes et d'alcools. Globalement, les mouches de Nouvelle-Écosse répondaient davantage aux traitements que celles du Québec, tandis que les mouches mâles exhibaient un plus grand nombre de vols. Les mouches ayant acquis de l'expérience étaient moins stimulées par les traitements que les mouches naïves. Cette recherche a franchie une étape préliminaire à l'identification de substances volatiles de fruits hôtes pouvant attirer des adultes R. mendax. Ces résultats appuient l'hypothèse selon laquelle les mélanges d'appâts volatiles doivent être produits de composés spécifiques afin d'être attirant pour l'insecte. Il est également suggéré pour des expériences futures d'utiliser des mouches inexpérimentées, soit mâles ou femelles, provenant du même emplacement géographique.
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Zaspel, Jennifer Michelle. « Systematics, biology, and behavior of fruit-piercing and blood-feeding moths in the subfamily Calpinae (Lepidoptera : Noctuidae) ». [Gainesville, Fla.] : University of Florida, 2008. http://purl.fcla.edu/fcla/etd/UFE0023641.
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Friberg, Urban. « Sexual conflict and male-female coevolution in the fruit fly ». Doctoral thesis, Umeå : Department of Ecology and Environmental Science, Umeå University, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-735.
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Abountiolas, Marvin. « In Vitro and In Vivo Antioxidant Capacity of Synthetic and Natural Polyphenolic Compounds Identified from Strawberry and Fruit Juices ». Scholar Commons, 2016. http://scholarcommons.usf.edu/etd/6057.
Texte intégralRésumé :
Strawberries can be considered a functional food because their consumption has been associated with several health benefits. They are important sources of bioactive compounds, such as vitamins and polyphenolic compounds, with recognized antioxidant capacity (AOC). However, strawberry overall quality and bioactive content are greatly affected by environmental conditions during pre- and post-harvest and, little is known about the stability of its bioactive compounds, specifically ascorbic acid (AA) and polyphenolics compounds. Furthermore, additional research that addresses the impact of polyphenolic compounds on in vitro and in vivo models is needed to understand the mechanisms behind their potential health benefits. Therefore, the objectives of the work presented in this thesis were to: 1) evaluate the impact of different disease control treatments on strawberry bioactive compounds and AOC; 2) understand the relationship between bioactive compounds and AOC in strawberries and fruit juices; 3) investigate the origin of AOC in strawberries by identifying their major polyphenolic compounds and, 4) explore the effects of polyphenol-rich fruits and fruit juices on the proliferation of cancer cells and lifespan of Caenorhabditis elegans.
Conscientious consumers are aware of the health benefits of substantial fruit and vegetable consumption but are also concerned about the amount of pesticide residues that can be found in conventionally grown produce, with pesticide-free produce (i.e., organic) becoming more popular. However, the market price for organic strawberries can be more than twice that of conventionally grown fruit which discourages the average American from purchasing this fruit on a regular basis. Therefore, in the first study presented in this thesis, we hypothesized that reducing pesticide usage would provide the consumer with a “sustainable strawberry” that would have better or similar quality at a lower cost than organic fruit while it would also reduce environmental impact and risk to pesticide applicators. Results from this study showed that strawberries from a reduced fungicide treatment, had better or similar bioactive content and AOC than fruit from the conventional disease control treatment. After cold storage, strawberries from the reduced or conventional disease control treatments showed comparable amounts of bioactive compounds and AOC. These results indicate that growing strawberries with a reduced number of fungicide applications can be an alternative to the conventional disease control or organic practices as it may reduce residual fungicides in the fruit, decrease production costs while still retaining important bioactive compounds.
In order to understand the relationship between bioactive compounds and AOC in strawberries and fruit juices, 56 different types of commercial beverages were chosen for the second study presented in this thesis. Overall, results showed that the higher the total phenolic contents (TPC) in the beverage the higher their AOC. Amongst all beverages studied, aronia, blackcurrant, and pomegranate juices contained the highest amount of TPC and AOC. Furthermore, after opening the bottles, these juices were maintained for 14 days at 4 °C, to test the stability of their TPC which was in general relatively stable throughout storage.
Further investigation on individual polyphenolic compounds and their possible contribution to the overall AOC of fruits and fruit juices, led to a third study. Overall, results showed that the AOC of major individual polyphenolic compounds found in strawberries (i.e., pelargonidin, cyanidin, ellagic acid, quercetin, kaempferol, catechin, epicatechin, caffeic acid, p-coumaric acid, ferulic acid) was significantly higher than that of mixtures of the same compounds. In addition, the AOC of strawberries correlated with its major bioactive compounds (i.e., polyphenolic compounds and ascorbic acid) in a form of a synthetic bioactive strawberry model (“Powerberry”) composed of major strawberry polyphenolic compounds, vitamin C, fructose and glucose in the same ratios found in a real strawberry. These results suggest that even though strawberries contain many different polyphenolic compounds and vitamins, their AOC might only depend on few compounds that are found in significant quantities in the fruit.
Finally, using cell and worm models we were able to demonstrate that conventional and organic strawberry, raspberry and blueberry fruits, and aronia, blackcurrant and pomegranate juices successfully inhibited the proliferation of HeLa cervical cancer cell lines. In addition, when introduced in low doses (0.75 mg ml-1 or lower) to the C. elegans diet, aronia, blackcurrant and pomegranate juices promoted longevity. Overall, results suggest that using whole fruit or fruit juices might constitute an alternative of treating cancer cells in vivo and that polyphenolic compounds contained in fruits and fruit juices displayed significant bioactivity in a worm model.
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Rolle, Rosa Sonya. « Isolation and characterization of enzymatic activity mediating cytokinin and purine metabolism in tomato fruit / ». The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487585645577558.
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Ferguson, Kaye. « The biology, ecology and management of the Quandong moth, Paraepermenia santaliella (Lepidoptera : Epermeniidae) ». Title page, contents and summary only, 2001. http://web4.library.adelaide.edu.au/theses/09PH/09phf3523.pdf.
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Includes bibliographical references (leaves 217-230). Details the biology and life history of the Quandong moth and investigates management strategies that would enable growers to manage the pest in an economically and environmentally sustainable program.
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Butts, John Charles. « Tracking the Sequences of Regulatory Linkages and Their Evolution Within a Fruit Fly Gene Regulatory Network ». University of Dayton / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1352918524.
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Kelly, Katrina E. « Synthesis, Oxidation, and Distribution of Polyphenols in Strawberry Fruit During Cold Storage ». Scholar Commons, 2018. https://scholarcommons.usf.edu/etd/7314.
Texte intégralRésumé :
Plants inherently produce polyphenols (i.e., antioxidants) as a response to reduce oxidative stress caused by abusive environmental pre- and postharvest conditions. These antioxidants, as well as vitamin C, are present in considerable levels in strawberries; however, excessive oxidative stress brought on by improper postharvest handling conditions can reduce the levels of antioxidants in the fruit and shorten the shelf-life of strawberries. Nevertheless, it may be possible to utilize strawberry’s naturally occurring polyphenols to reduce postharvest stress and extend their shelf life. The polyphenolic profile has been previously investigated in several strawberry cultivars, however no studies have determined the unique polyphenolic profiles of three important Florida strawberry cultivars (‘Florida Radiance’, Sweet Sensation® ‘Florida 127’and ‘Florida Beauty’) at harvest and during cold storage. Therefore, in order to better understand the distribution of individual polyphenols within these cultivars and their impact on postharvest shelf-life, this study examined the polyphenolic profiles throughout 7 days of cold storage (1 °C) using an HPLC-DAD. The activity of phenylalanine ammonia lyase (PAL), a key enzyme in the biosynthesis of polyphenols, and polyphenol oxidase (PPO), the enzyme responsible for polyphenol degradation, were also examined during cold storage to understand their possible influences on postharvest synthesis or degradation of polyphenols. This study revealed that the polyphenolic profile of strawberry fruit was genotype dependent; however, pelargonidin 3-glucoside was consistently the anthocyanin found in higher concentrations in the fruit regardless of the cultivar. Apart from the anthocyanins, the flavonols showed the most variation among the three cultivars. PAL was slightly induced during strawberry postharvest storage suggesting that a stress response occurred during cold storage while PPO showed variable induction patterns across all three cultivars most likely due to their different polyphenol profiles. Analysis of the distribution of polyphenols in the cortex and pith of strawberries showed that polyphenols were mostly concentrated in the cortex of the fruit and that the concentration of individual polyphenol in each fruit tissue varied by cultivar. These results indicate that the oxidative stress response varies in each of the strawberry cultivars studied contributing to their unique polyphenolic profile. Results from this study can ultimately help to identify the polyphenols and enzymes related to superior postharvest quality in future studies.
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Al-Hazzouri, Abbas. « Effect of sodium catchments on soluble soil salts, leaf ion concentration, and the yield of fruit in a water harvesting system ». Diss., The University of Arizona, 1990. http://hdl.handle.net/10150/184973.
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This study consisted of field experiments to determine the effect of sodium catchment on the distribution of soluble salts and exchangeable ions in soil, leaf ion concentration, and yield of peaches. The experiments were conducted at the Oracle Agricultural Center, formerly known as Page Ranch, University of Arizona, for a period of two years. The soil in this area is White House sandy clay loam. Sodium chloride salt was applied at a rate of 11.2 ton/ha to the Sodium Treated Catchment Area (STCA). Also, sulfur was applied at a rate of.5 kg m⁻² to Cropped Water Ways (CWW). Four peach cultivars planted in single rows with 2, 3 and 4 meter spacing in one cropped waterway, were selected for this study. Soil samples were collected at 20 cm intervals to a total depth of 160 cm. Twelve sites were selected in the CWW, three sites were selected in the STCA and one site chosen Outside Water Harvesting System (OWS). Also, 12 soil samples were collected from the three sites at different depths in CWW. Soil samples were then analyzed for pH, EC, C²⁺, Mg²⁺, Na⁺, K⁺, Cl⁻ and SO₄⁻². Four runoff samples were collected at CWW and their EC, Ca²⁺, Mg²⁺, Na⁺, K⁺, Cl⁻, SO₄⁻², and HCO₃⁻ contents were analyzed. Twelve peach leaf samples, one sample from each replicate, were collected and analyzed for Ca²⁺, Mg²⁺, Na⁺, K⁺, Cl⁻ and SO₄⁻². A computer model was developed to predict the actual fruit yield. The results of these experiments showed that no salinity problems have occurred in CWW, a good water quality resulted from sodium catchment and ten years after sodium was added to the soil, 65% of it still remains in the upper profile of STCA. Soil cation distribution was approximately the same at different depths for K⁺ and Mg²⁺, but had a different distribution pattern for Na⁺ and Ca²⁺ in the CWW. A significant correlation was found between soil depth, and pH, EC, and SAR. There was not significant difference in leaf uptake of Ca²⁺, SO₄⁻², Na⁺, and Cl⁻ using the same variety of peach with different spacing or different varieties with the same spacing. The results also showed that the interaction between variety and spacing did not significantly affect the yield in 1988, and significantly affected the yield in 1989.
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Hamilton, Brooke. « Evaluating the Developmental Instability-Sexual Selection Hypothesis in the Fruit Fly, Drosophila bipectinata (Diptera : Drosophilidae) ». University of Cincinnati / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1288377680.
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Fisk, Tylar S. « Quality Changes in Grafted Pepper (Capsicum annumm L.) Scion Fruit ». The Ohio State University, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=osu1511899552661231.
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Ant, Thomas. « Genetic control of the olive fruit fly, Bactrocera oleae ». Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:43f97545-f631-43cc-991c-7edb6dd71d2d.
Texte intégralRésumé :
The olive fruit fly, Bactrocera oleae, (Rossi) (Diptera:Tephritidae), is a key pest of olive crops. The sterile insect technique (SIT) is an environmentally benign and species-specific method of pest control, aiming to reduce the reproductive potential of a wild population through the mass-release of sterile insects. Previous olive fly SIT trials, involving the release of gamma-ray sterilised mixed-sex populations, achieved limited success. Key problems included altered diurnal mating rhythms of the laboratory-reared insects, leading to assortative mating between released and wild populations, and low competitiveness of the radiation sterilised mass-reared flies. Consequently, the production of competitive, male-only release cohorts is seen as essential. The RIDL (Release of Insects carrying a Dominant Lethal) system is a transgene-based derivative of SIT, one version of which involves the mass release of insects carrying a female specific lethal transgene (fsRIDL). This thesis describes: 1) the development of fsRIDL olive fly strains and the molecular analysis of transgene insertion and function; 2) the analysis of strain life-history parameters; 3) studies into sexual selection and mating compatibility; 4) a caged proof-of-principle population suppression trial; and, 5) selection dynamics on the fsRIDL trait in caged populations. Olive fly fsRIDL strains were developed with full female-lethal penetrance and repressibility. The lead strain displayed similar life-history and sexual competitiveness traits to those of the wild-type strain from which they were derived. In addition, transgenic males showed photoperiod compatibility and strong sexual competitiveness with field-collected wild olive flies. The feasibility of the fsRIDL approach was demonstrated when repeated male releases caused eradication of caged olive fly populations. Although needing field confirmation, these results suggest that fsRIDL olive fly strains may help to mitigate key problems experienced in previous olive fly SIT trials, and could help form the basis of a renewed effort towards olive fly SIT control.
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Bobiwash, Kyle. « Pollination ecology of lowbush blueberry (Vaccinium angustifolium) - The role of introduced pollinator communities, self-fertilization and somatic mutations on fruit set response ». Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114589.
Texte intégralRésumé :
This thesis examines fruit yield variation and its causes in the lowbush blueberry (Vaccinium angustifolium). I found that yields exhibits significant variability in fruit within and between fields. An experiment involving controlled introductions of the three pollinator species commonly used in blueberry production—the honeybee (Apis mellifera), the bumblebee (Bombus spp.) and leafcutter bee (Megachile rotundata)—was also conducted. Increasing the abundance or diversity of the introduced pollinator community did not systematically increase fruit set across the experimental populations. There is weak evidence to suggest the combination of bumblebee and leafcutter bee may be more effective at increasing fruit yield than honeybee alone. The behaviour of introduced pollinator species differed between fields depending on the combination of pollinator species present, however, none of these changes was correlated with increased fruit set. As part of this work, self-pollinations and cross-pollinations were conducted in a large number of clones and variation in inbreeding depression of yield was detected among clones. To evaluate whether differences in accumulated deleterious mutations among clones were responsible for variation in inbreeding depression, a follow-up experiment manipulating access to self pollen was undertaken. In addition, differential genetic load was measured, using clone size as a proxy for somatic cell division. Neither clonal size nor self pollen access sufficiently explained the interclonal variation in self fruit set. Within the same fields, geitonogamously-pollinated fruit set was greater than autogamously-pollinated fruit set. These differences suggest the presence of somatic mutations, cell lineage selection, mitotic recombination, or epigenetic changes within lowbush blueberry clones, and they mirror results from studies of several perennial plant species that have revealed autogamy depression to be a significant factor in plant fertility. These results suggest that self-fertilization is an important element limiting fruit set that should be addressed in attempts to increase lowbush blueberry yield.Ce thèse explore la variance du rendement de fruit et les causes des différences dans le rendement vue dans l'espèce de bleuet Vaccinium angustifolium. J'ai trouvé qu'il existe une variabilité dans le rendement de fruit entre les champs et entre les individus du champs. Une expérience visant l'introduction des trois espèces pollinisateur utilisé le plus fréquement (Apis mellifera, Bombus spp., Megachile rotundata) au Nouveau-Brunswick a aussi eu lieu. Lors de l'augmentation de la diversité ou l'abondance il n'y avait aucun gain conséquent dans le rendement de fruit. Il y a un faible temoignage qui suggère que le rendement de fruit est plus élevé dans les champs qui inclut la combinaison pollinisateur de Bombus et Megachile comparé au champs seulement avec Apis introduit. Les mesures de comportement des pollinisateur introduit ont aussi varié entre les champs dépendant des espèces présent dans les champs, mais ces changements en comportement n'ont pas été lié au différences dans le rendement de fruit. Comme partie de cette recherche, des auto- pollinisations et des pollinisations croisée ont eu lieu dans plusieurs clones, avec une variabilité dans la dépression de consanguinité vue entre individus. Pour evaluer si des différences dans l'accumulation des mutations somatiques entre individus sont responsable pour la variabilité dans la dépression de consanguinité, une expérience qui a but de modifié accès de auto pollen a suivie. Pour mésurer la différence en charge génétique, la taille des clones a été utilisé pour représenter la division cellulaire somatique. Ni la taille des clones ou l'accès à l'auto pollen fut capable d'expliquer la variation de rendement de fruit entre les clones. Ces mêmes champs on aussi produit un taux de rendement de fruit plus élevé dans les fleurs fécondé avec le pollen geitonogamous comparé au fleurs fécondé avec le pollen autogame. Ces différences suggèrent la présence des mutations somatiques, la sélection lignée cellulaire, la recombinaison mitotique, ou des changement épigénétique dans les clones de bleuets, et ces résulats reflète d'autres études des espèces de plantes vivaces qui indique que la dépression autogame est une force significative dans la fertilié des plantes. Nos résultats suggèrent que l'auto pollinisation joue un rôle important dans la limitation du rendement de fruit et dois être considéré lorsqu'on essai d'augmenter le rendement de fruit chez le bleuet V. angustifolium.
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Widmayer, Heather. « Biogeographical patterns associated with genome-wide genetic differentiation in a widespread species of South American Blepharoneura fruit flies (Tephritidae) ». Thesis, University of Iowa, 2018. https://ir.uiowa.edu/etd/6337.
Texte intégralRésumé :
Studying how new insect species originate can help us better understand the evolutionary processes that lead to the rich insect biodiversity found in the tropics. New insect species arise via the evolution of reproductive isolation, a result of the accumulation of reproductive isolating barriers. Reproductive isolating barriers can arise in the context of geographical isolation and/or can be influenced by differences in ecology. Complex evolutionary mechanisms may underlie the origins of the more than 40 species of neotropical fruit flies in the genus Blepharoneura (Diptera: Tephritidae). The immature stages of these flies are specialist feeders on plants in the Cucurbitaceae (cucurbit) family in Central and South America. Previous research focusing on six geographically widespread Blepharoneura species used 18 microsatellite loci to identify patterns of geographical and ecological divergence. While conclusions from microsatellite data are valid, these markers provide only a limited signal of genetic structure. Fine-scale, genome-wide data can reveal patterns of genetic differentiation that may help us discover and date historical and recent lineage divergence. Here I use double-digest restriction-associated DNA (ddRAD) sequencing to explore the hypothesis that geographic and ecologic barriers are restricting gene flow in one species of Blepharoneura, B. sp10. First, I use two methods to detect population structure within B. sp10 individuals. I find evidence for three distinct genetic groups characterized by geography and one genetic group defined by a difference in host plant use. Then I investigate these relationships using Mantel tests and pairwise spatial-genetic plots, which reveal distinct biogeographical genetic patterns. Finally, I infer the evolutionary history of B. sp10 using approximate Bayesian computation and find that the timing of divergence between flies collected from the Amazon Basin and those collected from the Guiana Shield coincides with the late Pleistocene, between 24,412 and 83,000 years ago. Connecting these results to historical climate data from the Late Pleistocene may help explain evolutionary processes that contributed to the patterns of genetic diversity that we see in Blepharoneura. This research provides a framework for investigating the biogeographic and evolutionary history of the more than 50 species in the Blephaorneura genus, a step towards understanding the complexity of insect diversity in the tropics.
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Stone, William E. « Control and Evaluation of Big Game Browsing Damage to Commercial Fruit Orchards ». DigitalCommons@USU, 1988. https://digitalcommons.usu.edu/etd/6416.
Texte intégralRésumé :
Diversionary feeding, artificial feeding designed to divert animals away from areas where they might cause property damage, was tested for efficacy in reducing fruit orchard browsing by big game animals during two consecutive winters in Utah. Strategically placed attractive feedstuffs lured deer to feed stations and reduced fruit-bud browsing (1st year, P< 0.07; 2nd year, P < 0.01). Blossom and apple numbers were greater (P < O. 05) on trees in the feed (treatment) orchard than in the no feed (control) orchard in each year. However, higher (P < 0.05) apple production on trees where browsing was excluded in the treatment orchards compared to the control orchards indicated that intercept feeding did not increase crop production. Tree periodicity and other factors affecting apple production masked the effect of diversionary feeding on crop yield. Two independent browsing damage assessment methods, a paired-tree technique and a harvest-inflation technique, predicted that the ratio of apples lost per browsed bud was 0.158 and 0.082, respectively. However, the values of the ratio varied widely with each method of estimation. Browsing damage differed (P < o. 001) according to branch position (below 1 m and distal, above 1 m and distal, and above 1 m and proximal to the tree trunk). A less intensive count of buds and browsed buds reliably predicted average browsing damage in the orchard (determined by counting all browsing zone buds on 5% of the orchard trees), when these branch classes were used. An economic analysis of this feeding program indicated that, at current prices, the value of the increased crop in the study orchards did warrant the cost of feeding associated with them (benefit/cost= 9.20 and 32.89). Deer-proof fencing, although expensive to install, is a more cost-efficient (benefit/cost= 129.28 and 121.11) method of preventing browsing damage in the orchards I studied.
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Kölling, Nils. « Quantitative genetics of gene expression during fruit fly development ». Thesis, University of Cambridge, 2016. https://www.repository.cam.ac.uk/handle/1810/256090.
Texte intégralRésumé :
Over the last ten years, genome-wide association studies (GWAS) have been used to identify genetic variants associated with many diseases as well as quantitative phenotypes, by exploiting naturally occurring genetic variation in large cohorts of individuals. More recently, the GWAS approach has also been applied to highthroughput RNA sequencing (RNA-seq) data in order to find loci associated with different levels of gene expression, called expression quantitative trait loci (eQTL). Because of the large amount of data that is required for such high-resolution eQTL studies, most of them have so far been carried out in humans, where the cost of data collection could be justified by a possible future impact in human health. However, due to the rapidly falling price of high-throughput sequencing it is now also becoming feasible to perform high-resolution eQTL studies in higher model organisms. This enables the study of gene regulation in biological contexts that have so far been beyond our reach for practical or ethical reasons, such as early embryonic development. Taking advantage of these new possibilities, we performed a high-resolution eQTL study on 80 inbred fruit fly lines from the Drosophila Genetic Reference Panel, which represent naturally occurring genetic variation in a wild population of Drosophila melanogaster. Using a 3′ Tag RNA-sequencing protocol we were able to estimate the level of expression both of genes as well as of different 3′ isoforms of the same gene. We estimated these expression levels for each line at three different stages of embryonic development, allowing us to not only improve our understanding of D. melanogaster gene regulation in general, but also investigate how gene regulation changes during development. In this thesis, I describe the processing of 3′ Tag-Seq data into both 3′ isoform expression levels and overall gene expression levels. Using these expression levels I call proximal eQTLs both common and specific to a single developmental stage with a multivariate linear mixed model approach while accounting for various confounding factors. I then investigate the properties of these eQTLs, such as their location or the gene categories enriched or depleted in eQTLs. Finally, I extend the proximal eQTL calling approach to distal variants to find gene regulatory mechanisms acting in trans. Taken together, this thesis describes the design, challenges and results of performing a multivariate eQTL study in a higher model organism and provides new insights into gene regulation in D. melanogaster during embryonic development.
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De, Jager Zoe Marthalise. « Biology and ecology of the false codling moth, Thaumatotibia leucotreta (Meyrick) ». Thesis, Stellenbosch : Stellenbosch University, 2013. http://hdl.handle.net/10019.1/95453.
Texte intégralRésumé :
Thesis (MSc)--Stellenbosch University, 2013.ENGLISH ABSTRACT: Thaumatotibia leucotreta, the false codling moth (FCM), is a phytosanitary pest in South Africa posing a substantial threat to many of the country’s international export markets. Its pest status is of high importance because it has a wide ecological range and has been reported in all areas where citrus is produced in South Africa. Many methods of control have been implemented, such as chemical and cultural control, mating disruption and sterile insect releases. There was a need to obtain a more accurate understanding of FCM biology on deciduous fruit in South Africa and this then us to pose the questions described in the chapters to follow. The first aim was focused on the possibility of FCM diapause during winter. If FCM were to undergo diapause this could pose further problems for control methods, but knowledge thereof could also assist in more accurate and timely control methods. Considering past research on other Lepidoptera species, four physiological traits were chosen as indicative of a diapause state. Water loss rate, metabolic rate and the supercooling points should be lower if the individuals were in a diapause state, with a higher fat content expected for these individuals. Diapause induction was attempted through a gradual lowering of the environmental temperature in combination with longer nights to simulate overwintering conditions. Diapause was not observed in these experimental individuals. The second aim was to better understand the field biology of FCM. This was studied through in-field flight ability studies and damage assessments on four fruit kinds. Six release dates were used to measure the flight ability. The highest recapture rates were at minimum temperatures above 16°C and maximum temperatures averaging above 30°C, although the recapture rates were not significant in relation to the amount released. The recapture rates in the different fruit kinds were not significantly different, with the amount recaptured at the closest distance of 30 m being significantly more than that of the other distances. This was also only for the last release at the warmest temperatures. Fruit damage assessments were conducted and we were able to rear wild FCM from Granny smith apples, Forelle pears, Larry Ann plums and Satsuma and Clementine citrus cultivars. Citrus infestations had the highest count and a prolonged occurrence compared to the other varieties, due to its later harvest period. The third aim was to study the developmental parameters of FCM in different fruit kinds and an artificial medium. Firstly, FCM did not infest apples, Royal Gala and Pink lady’s, under laboratory conditions. Results were obtained using Forelle pears, Clementines and Thompson seedless grapes. On average the grapes had the shortest FCM developmental time from egg to adult stage, followed by oranges and then pears. Pears had the lowest developmental success rate, with that of oranges and grapes being much higher. Infestations took place at the stalk end of the fruit for the grapes and oranges, with the pears being infested at the calyx end. Future research should include an in-field life cycle, to determine the life cycle of FCM on different economically important fruit kinds under field conditions. The focus could also be shifted to where FCM overwinter, leading to better preventative control leading to lower infestation pressure during harvest periods. This is of utmost importance in an environment where maximum residue levels for pesticides dictate market access.
AFRIKAANSE OPSOMMING: Thaumatotibia leucotreta, die vals kodling mot (VKM) is ‘n fitosanitere pes in Suid Afrika, wat kan lei tot groot finansiele verliese. Die VKM se wye gasheerreeks en die feit dat dit al in al die sitrus verbouings-areas in Suid Afrika opgelet is, maak dit ‘n ernstige pes. Daar word van verskeie beheer metodes gebruik gemaak, insluitend chemiese en kulturele metodes. In sommige areas word daar ook van paaringsontwrigting en steriele insek vrylatings gebruik gemaak en hierdie metodes word gewoonlik met ander gekombineer. Daar is ‘n groot behoefte vir meer inligting omtrent die status van VKM in sagtevrugte in Suid Afrika en het gelei tot die vrae wat in hierdie studie aangespreuk word. Die eerste doelwit was om te bepaal of die VKM wel diapouse ondergaan. Dit sal verskeie beheermetodes belemmer, maar kennis hiervan kan meer gefokusde en gevolglik meer effektiewe beheermaatreels tot gevolg hê. Daar is gekyk na vier fisiologiese eienskappe wat beduidend tot diapouse van ander Lepidoptera spesies is. Daar word verwag dat VKM wat diapouse ondervind ‘n hoër vetinhoud sal he, terwyl die metabolise tempo, “supercooling’ punte en tempo van waterverlies laer sal wees. Hierdie eienskappe kon egter nie by die individue geidentifiseer word nie. Ons het diapouse probeer induseer deur gebruik te maak van ‘n gesimuleerde oorgang na winterstoestande in die laboratorium. Die toestande het toegelaat vir korter dae en laer gemiddelde temperature gedurende beide die dag en nag. Die tweede doelwit waarna gekyk is, is die bepaling van VKM se beweging in die boorde en die vrugskade op verskillende vrugsoorte. Daar kon ‘n duidelike tendens geidentifiseer word in die toename van VKM hervangs by temperature bo ‘n minimum van 16°C en gemiddelde maksimum bo 30°C. Daar was 6 vrylatings periodes, met geen betekenisvolle getalle van hervangs nie. Daar was geen betekenisvolle verskille tussen die hervangsgetalle in die verskillende vrugsoorte nie, alhoewel die 30m lokval ‘n betekenisvol hoër gemiddelde hervangs gehad het, in vergelyking met lokvalle by 60m en 90m. Die hoeveelheid vrugskade is ook gemonitor op Granny smith appels, Forelle pere, Larry Ann pruime en Satsuma en Clementine sitrus kultivars. Die vrugte is na die laboratorium geneem waar die VKM tyd gegee is om uit te broei. Al die vrugsoorte het VKM volwassenes opgelewer, maar die eksperiment kon nie op appels in die laboratorium herhaal word tydens die toets van verkillende onwikkeling stadiums nie. Ons glo dus die VKM wat hier vanaf appels uitgebroei het, is weens sekondere infeksies in die boorde. Die hoogste skadetelling is in die sitrusboord gevind. Die derde doelwit was om die duur van onderskeie ontwikkeling stadiums te bepaal op vier vrugsoorte, sowel as op ‘n kunsmatige medium. Ons het ondervind dat die VKM nie Royal Gala of Pink lady kultivars kan infesteer onder laboratorium toestande nie. Die vrugsoorte wat dus ontwikkeling kon onderhou was Forelle pere, Clementines en Thompson pitlose druiwe. Die ontwikkeling vanaf eier na volwasse stadium was die kortste op druiwe, gevolg deur lemoene en pere. Die pere het die minste VKM onderhou in vergelyking met die lemoene en druiwe. Al die vrugte is binnegedring naby die aansluiting van die stingel aan die vrugte, behalwe die pere wat nader aan die kelk binnegedring is. Toekomstige navorsing sal gefokus moet word op die lewenssiklus in die veld, vir die verskillende vrugsoorte. Daar sal ook gekyk moet word na die spesifieke alternatiewe gashere of plekke waar die VKM kan oorwinter sodat beheer meer voorkomend plaas kan vind. Dit sal infestasie vlakke onderdruk, om veral laer druk tydens oesperiodes te verseker. Dit is uiters belangrik om beheer stategieë te kombineer met die hoeveelheid druk vanaf uitvoermarkte oor maksimum residu vlakke van chemiese middels.
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Madden, Robert T. « Biochemical and Proteomic Approaches to Determine the Impact Level of Each Step of the Supply Chain on Tomato Fruit Quality ». Scholar Commons, 2019. https://scholarcommons.usf.edu/etd/7853.
Texte intégralRésumé :
Fresh fruits and vegetables (FFVs) are the most frequently wasted foods because of their perishability and handling requirements. However, there is a lack of information on how much each step of the supply chain impacts FFVs quality, particularly on tomatoes, and what measures need to be taken for an immediate and effective impact on waste reduction. There is also no information on how the supply chain affects the proteome of the tomato and what proteins are differentially regulated by the most impactful steps of the supply chain. The objectives of the work presented on this thesis were to evaluate the decline in the overall quality and quantify tomato waste at each step of the supply chain, from the farm to consumer; and to determine what proteins are impacted by the decline in quality that is associated with temperature abuse. To determine overall quality and tomato waste, light-red tomatoes were exposed to an optimum temperature (13 °C) and eighteen different time-temperature scenarios, normally encountered during supply chain, and sensory and physicochemical attributes measured at each step. To determine the impact of chilling and non-chilling temperatures normally encountered during tomato supply chain, on the proteome, light-red tomatoes were exposed to an optimum temperature (13 °C) and to two time and temperature supply chain scenarios (2 °C and 25 °C) that showed the most negative impact on tomato overall quality, and physicochemical and proteomic attributes were measured at each step. For the first tomato harvest, the steps with the highest impact on quality and waste were shipping to distribution center (DC; 20°C), cooling at the grower (25°C) and storing at the consumer (4°C). For the second tomato harvest, shipping to the store (2°C), cooling at the farm (10°C) and displaying at the store (20°C) negatively impacted quality. High temperatures during cooling, shipping and
store display impacted sensory quality and resulted in increased weight loss, and decreased sugar, carotenoids, and ascorbic acid contents. Although low temperatures during shipping, cooling and consumer did not impact tomato sensory quality, they contributed to a decline in sugar, carotenoids and ascorbic acid contents. Overall, the most impactful steps on tomato quality and waste, regardless of the temperature, were shipping to DC, cooling, shipping to stores, displaying at the store, and consumer storage. Analysis of the differentially expressed proteins in the tomato showed that metabolic proteins were greatly impacted by temperature abuses such as phosphomannomutase, heme oxygenase 1, and MAP kinase; and that proteins regulating cellular membrane integrity such as vacuolar protein sorting-associated protein were also impacted.
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Li, Lei. « A behavioral assay for monitoring food self-administration and movement in real-time in fruit fly and its application in alcohol research ». Thesis, Uppsala universitet, Institutionen för biologisk grundutbildning, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-446083.
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Xu, Jiaxin. « Exploration du polymorphisme moléculaire et protéique de la tomate pour l’identification de QTL de qualité du fruit ». Thesis, Avignon, 2012. http://www.theses.fr/2012AVIG0644/document.
Texte intégralRésumé :
L’amélioration de la qualité du fruit de tomate dépend largement de la variation génétique. A la suite de la domestication et de la sélection moderne, la diversité moléculaire chez la tomate a été profondément réduite, limitant les possibilités d’amélioration. De nouveaux marqueurs moléculaires révélant les polymorphismes nucléotidiques (SNP) constituent des outils précieux pour saturer les cartes génétiques et identifier des QTL (quantitative trait loci) et des associations chez une espèce peu polymorphe comme la tomate. Les objectifs de cette étude étaient de caractériser la diversité génétique de la tomate au niveau moléculaire et de tenter d’identifier des QTL, des gènes et des protéines responsables de la variation de caractères de qualité du fruit. Pour cela, trois études indépendantes ont conduit à (1) la découverte de nouveaux marqueurs SNP, (2) leur utilisation en génétique d’association et (3) l’analyse de la diversité du protéome en relation avec des caractères physiologiques du fruit.Dans la première étude, nous avons comparé deux plateformes de reséquençage pour reséquencer des zones ciblées couvrant environ 0.2% du génome de deux accessions contrastées. Plus de 3000 SNP sont été identifiés. Nous avons ensuite validé 64 SNPs en développant des marqueurs CAPS. Nous avons ainsi montré l’intérêt des techniques de reséquençage pour la découverte de SNP chez la tomate et produit des marqueurs simples qui peuvent être utiles pour caractériser de nouvelles ressources.Nous avons ensuite développé un ensemble de 192 SNPs et génotypé une collection de 188 accessions comportant des accessions cultivées, des types “cerise” et des formes sauvages apparentées et recherché des associations avec 10 caractères de qualité du fruit. Une quarantaine d’associations a été détectée dans des régions où des QTL avaient été préalablement identifiés. D’autres associations ont été identifiées dans de nouvelles régions. Nous avons ainsi confirmé le potentiel de la génétique d’association pour la découverte de QTL chez la tomate. Finalement une approche combinant l’analyse du protéome, du métabolome et de traits phénotypiques a été mise en oeuvre pour étudier la variabilité naturelle de la qualité du fruit de huit lignées contrastées et de quatre de leurs hybrides, à deux stades de développement (expansion cellulaire et orange-rouge). Nous avons identifié 424 spots protéiques variables en combinant électrophorèse bidimensionnelle et nano LC MS/MS et construit une carte de référence du protéome de fruit de tomate. En parallèle, nous avons mesuré la variation de teneurs en 34 métabolites, les activités de 26 enzymes et cinq caractères phénotypiques. La variabilité génétique et les modes d’hérédité ont été décrits. L’intégration des données a été réalisée par construction de réseaux de corrélations et régression sPLS. Plusieurs associations ont été détectées intra et inter niveau d’expression, permettant une meilleure compréhension de la variation de la qualité des fruits de tomateFruit quality in tomato is highly dependent on genetic variation. Following domestication and modernbreeding, molecular diversity of tomato has been strongly reduced, limiting the possibility to improvetraits of interest. New molecular markers such as single nucleotide polymorphisms (SNP) constituteprecious tools to saturate tomato genetic maps and identify quantitative trait loci (QTL) andassociations in a poorly polymorphic species like tomato. The objectives of this study were tocharacterize tomato genetic diversity at the molecular levels and to try to identify QTLs, genes andproteins responsible for fruit quality traits in tomato. For this purpose, three independent studies wereconducted leading to the discovery of new SNP markers, their use for association study and finally theanalysis of proteome diversity in relation to physiological phenotypes. We first used two nextgenrationsequencing platforms (GA2 Illumina and 454 Roche) to re-sequence targeted sequencescovering about 0.2% of the tomato genome from two contrasted accessions. More than 3000 SNPswere identified between the two accessions. We then validated 64 SNPs by developing CAPS markers.We thus showed the value of NGS for the discovery of SNPs in tomato and we produced low costCAPS markers which could be used to characterize other tomato collections. A SNPlexTM arraycarrying 192 SNPs was then developed and used to genotype a broad collection of 188 accessionsincluding cultivated, cherry type and wild tomato species and to associate these polymorphisms to tenfruit quality traits using association mapping approach. A total of 40 associations were detected andco-localized with previously mapped QTLs. Some other associations were identified in new regions.We showed the potential of using association genetics in tomato. Finally, a new analytical approachcombining proteome, metabolome and phenotypic profiling were applied to study natural geneticvariation of fruit quality traits in eight diverse accessions and their four corresponding F1s at cellexpansion and orange-red stages. We identified 424 variable spots by combining 2-DE and nano LCMS/MS and built the first comprehensive proteome reference map of the tomato fruit pericarp at twodevelopmental stages from the 12 genotypes. In parallel, we measured the variation of 34 metabolites,26 enzyme activities and five phenotypic traits. A large range of variability and several inheritancemodes were described in the four groups of traits. Data integration was achieved through sPLS andcorrelation networks. Many significant associations were detected within level and between levels ofexpression. This systems biology approach provides better understanding of networks of elements(proteins, enzymes, metabolites and phenotypic traits) in tomato fruits
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Wu, Shan. « The roles of OVATE and other elongation genes in regulating proximal-distal patterning of tomato fruit ». The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1437586702.
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Korzekwa, Dominika. « Filling in gaps of Drosophila melanogaster urate degradation metabolic pathway using metabolomics approaches : towards the core metabolome of the fruit fly ». Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7706/.
Texte intégralRésumé :
The primary goal of systems biology is to integrate complex omics data, and data obtained from traditional experimental studies in order to provide a holistic understanding of organismal function. One way of achieving this aim is to generate genome-scale metabolic models (GEMs), which contain information on all metabolites, enzyme-coding genes, and biochemical reactions in a biological system. Drosophila melanogaster GEM has not been reconstructed to date. Constraint-free genome-wide metabolic model of the fruit fly has been reconstructed in our lab, identifying gaps, where no enzyme was identified and metabolites were either only produced or consume. The main focus of the work presented in this thesis was to develop a pipeline for efficient gap filling using metabolomics approaches combined with standard reverse genetics methods, using 5-hydroxyisourate hydrolase (5-HIUH) as an example. 5-HIUH plays a role in urate degradation pathway. Inability to degrade urate can lead to inborn errors of metabolism (IEMs) in humans, including hyperuricemia. Based on sequence analysis Drosophila CG30016 gene was hypothesised to encode 5- HIUH. CG30016 knockout flies were examined to identify Malpighian tubules phenotype, and shortened lifespan might reflect kidney disorders in hyperuricemia in humans. Moreover, LC-MS analysis of mutant tubules revealed that CG30016 is involved in purine metabolism, and specifically urate degradation pathway. However, the exact role of the gene has not been identified, and the complete method for gap filling has not been developed. Nevertheless, thanks to the work presented here, we are a step closer towards the development of a gap-filling pipeline in Drosophila melanogaster GEM. Importantly, the areas that require further optimisation were identified and are the focus of future research. Moreover, LC-MS analysis confirmed that tubules rather than the whole fly were more suitable for metabolomics analysis of purine metabolism. Previously, Dow/Davies lab has generated the most complete tissue-specific transcriptomic atlas for Drosophila – FlyAtlas.org, which provides data on gene expression across multiple tissues of adult fly and larva. FlyAtlas revealed that transcripts of many genes are enriched in specific Drosophila tissues, and that it is possible to deduce the functions of individual tissues within the fly. Based on FlyAtlas data, it has become clear that the fly (like other metazoan species) must be considered as a set of tissues, each 2 with its own distinct transcriptional and functional profile. Moreover, it revealed that for about 30% of the genome, reverse genetic methods (i.e. mutation in an unknown gene followed by observation of phenotype) are only useful if specific tissues are investigated. Based on the FlyAtlas findings, we aimed to build a primary tissue-specific metabolome of the fruit fly, in order to establish whether different Drosophila tissues have different metabolomes and if they correspond to tissue-specific transcriptome of the fruit fly (FlyAtlas.org). Different fly tissues have been dissected and their metabolome elucidated using LC-MS. The results confirmed that tissue metabolomes differ significantly from each other and from the whole fly, and that some of these differences can be correlated to the tissue function. The results illustrate the need to study individual tissues as well as the whole organism. It is clear that some metabolites that play an important role in a given tissue might not be detected in the whole fly sample because their abundance is much lower in comparison to other metabolites present in all tissues, which prevent the detection of the tissue-specific compound.
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Bithell, S. L. « An evaluation of Solanum nigrum and S. physalifolium biology and management strategies to reduce nightshade fruit contamination of process pea crops ». Lincoln University, 2004. http://hdl.handle.net/10182/1160.
Texte intégralRésumé :
The contamination of process pea (Pisum sativum L.) crops by the immature fruit of black nightshade (Solanum nigrum L.) and hairy nightshade (S. physalifolium Rusby var. nitidibaccatum (Bitter.) Edmonds) causes income losses to pea farmers in Canterbury, New Zealand. This thesis investigates the questions of whether seed dormancy, germination requirements, plant growth, reproductive phenology, or fruit growth of either nightshade species reveal specific management practices that could reduce the contamination of process peas by the fruit of these two weeds. The seed dormancy status of these weeds indicated that both species are capable of germinating to high levels (> 90%) throughout the pea sowing season when tested at an optimum germination temperature of 20/30 °C (16/8 h). However, light was required at this temperature regime to obtain maximum germination of S. nigrum. The levels of germination in the dark at 20/30 °C and at 5/20 °C, and in light at 5/20 °C, and day to 50 % germination analyses indicated that this species cycled from nondormancy to conditional dormancy throughout the period of investigation (July to December 2002). For S. physalifolium, light was not a germination requirement, and dormancy inhibited germination at 5/20 °C early in the pea sowing season (July and August). However, by October, 100% of the population was non-dormant at this test temperature. Two field trials showed that dark cultivation did not reduce the germination of either species. Growth trials with S. nigrum and S. physalifolium indicated that S. physalifolium, in a non-competitive environment, accumulated dry matter at a faster rate than S. nigrum. However, when the two species were grown with peas there was no difference in dry matter accumulation. Investigation of the flowering phenology and fruit growth of both species showed that S. physalifolium flowered (509 °Cd, base temperature (Tb) 6 °C) approximately 120 °Cd prior to S. nigrum (633 °Cd). The fruit growth rate of S. nigrum (0.62 mm/d) was significantly faster than the growth rate of S. physalifolium (0.36 mm/d). Because of the earlier flowering of S. physalifolium it was estimated that for seedlings of both species emerging on the same date that S. physalifolium could produce a fruit with a maximum diameter of 3 mm ~ 60 °Cd before S. nigrum. Overlaps in flowering between peas and nightshade were examined in four pea cultivars, of varying time to maturity, sown on six dates. Solanum physalifolium had the potential to contaminate more pea crops than S. nigrum. In particular, late sown peas were more prone to nightshade contamination, especially late sowings using mid to long duration pea cultivars (777-839 °Cd, Tb 4.5 °C). This comparison was supported by factory data, which indicated that contamination of crops sown in October and November was more common than in crops sown in August and September. Also, cultivars sown in the later two months had an ~ 100 °Cd greater maturity value than cultivars sown in August and September. Nightshade flowering and pea maturity comparisons indicated that the use of the thermal time values for the flowering of S. nigrum and S. physalifolium can be used to calculate the necessary weed free period required from pea sowing in order to prevent the flowering of these species. The earlier flowering of S. physalifolium indicates that this species is more likely to contaminate pea crops than is S. nigrum. Therefore, extra attention may be required where this species is present in process pea crops. The prevention of the flowering of both species, by the maintenance of the appropriate weed free period following pea sowing or crop emergence, was identified as potentially, the most useful means of reducing nightshade contamination in peas.
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Sarchet, Penny. « The developmental and genetic basis of explosive pod-shatter in Cardamine hirsuta ». Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:08cff1dc-3d9a-4697-9f60-cf1601d9ed60.
Texte intégralRésumé :
Dispersal is a key trait across biology. Within plants, a variety of explosive seed dispersal mechanisms are seen. Whilst ecological and mechanical studies have described this important evolutionary adaptation in many species, a genetic and developmental understanding of explosive seed dispersal is lacking. In this thesis, the morphology and development of the explosive seed pods of Cardamine hirsuta – a member of the Brassicaceae – are characterised in detail, with reference to its close relative, the model organism A. thaliana. Comparison of fruit morphology between these two species and across other Brassicacean species generated hypotheses regarding the function and polarity of morphological features. In order to identify genes that are necessary for C. hirsuta fruit development, a genetic screen was conducted and a range of mutants identified and subsequently characterised. Analysis of the indehiscent valveless (val) mutant revealed a loss of valve tissue and an expansion of valve margin identity in the silique. Mapping and sequencing identified a mutation in the MADS-box gene FRUITFULL (FUL), which results in a truncated protein, as the likely cause of the val phenotype. Consideration of ful mutants in C. hirsuta and A. thaliana allowed comparison of the genetic patterning of the fruit dehiscence zone in these two species. The genetic interactions between fruit mutants characterised in this thesis and mutants in shoot patterning genes revealed common regulatory networks underlying leaf and fruit development in C. hirsuta. Together, comparison of wild-type and mutant C. hirsuta siliques with those of A. thaliana and other Brassicacean species suggests that specialised cell layers within the valve silique region are of key importance to C. hirsuta’s explosive dehiscence mechanism.