Dissertations / Theses: 'Fruit genetics'

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Muda, Pauziah. "Cell wall degradation during mango fruit ripening." Thesis, University of Nottingham, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.316943.

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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.

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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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Mhelembe, Khethani Give. "Molecular characterisation of ARC pome fruit collections in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2015. http://hdl.handle.net/10019.1/96716.

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Thesis (MSc)--Stellenbosch University, 2015.
ENGLISH ABSTRACT: Apple (Malus pumila Mill.) and pear (Pyrus communis L.), commonly known as pome fruits, are important deciduous fruit crops in South Africa. The challenges of climate change, disease incidence, distant markets and fluctuating consumer preferences necessitate new cultivars. The Agricultural Research Council (ARC) Infruitec-Nietvoorbij conducts a breeding programme aimed at developing new cultivars that are well adapted, resistant to pests and diseases and good storage potential. A recent review of the pome fruit gene banks, the breeders’ raw material, revealed misidentification and poor characterisation limitating the efficiency of its utilisation. To address these problems, the current study used microsatellite markers to investigate the trueness to type of accessions in the ARC gene banks. In addition, accessions of apple identified as true to type, were genotyped for the ACS1 gene involved with ethylene production and fruit ripening. Two sets of 12 microsatellite markers recommended by a European working group on Pyrus/Malus, one for apple and one for pear, were utilised to fingerprint 540 apple and 197 pear accessions. Eleven and eight of 12 markers, were used respectively to successfully discriminate across the apple and pear accessions, with the exception of clones and sports of particular cultivars. Where possible, fingerprints were compared with those of their reported parents. The use of recommended markers facilitated the comparison of ARC pear accessions with those of the collection in Brogdale (UK). Trueness to type of accessions were established and misidentified accessions were also detected. A similar comparison will be conducted for apple when the Brogdale apple accessions fingerprints become available. Several accessions were found to be false, 78 apple and 22 pear, and removal from the collection was recommended. For ACS1 genotyping of 292 apple accessions, customised fluorescently labelled ACS1-Pr were used rather than the published ACS1-5 primers. Of the 292 apple accessions, 29 were homozygous for the b allele associated with low ethylene and good storage potential. Novel size variation in one allele of the ACS1 gene, was detected in some Malus species and ornamental hybrids. Successful amplification in a multiplex reaction was achieved and proves to be a cost effective method for simultaneous molecular fingerprinting and ACS1 genotyping. True to type material will facilitate confident use of genetic resources in the breeding programmes, and the ACS1 genotypes will identify candidate parents for developing good storage performing cultivars for distant markets.
AFRIKAANSE OPSOMMING: Summary not available

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Ruklisa, Dace. "Large scale genomic association studies in fruit fly and human." Thesis, University of Cambridge, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.610178.

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Sonneveld, Tineke. "The molecular genetics of self-incompatibility in sweet cherry (Prunus avium)." Thesis, University of Nottingham, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.268519.

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Mollel, Margaret Huruma Naftali. "Towards a novel fruit crop : Micropropagation and genetic transformation of the indigenous fruit tree marula, Sclerocarya birrea subsp.caffra." Thesis, University of Limpopo ( Turfloop campus), 2005. http://hdl.handle.net/10386/1302.

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Thesis ( PhD. (Biotechnology )) --University of Limpopo, 2005
The marula tree (Sclerocarya birrea subsp. caffra), an indigenous, multipurpose, drought tolerant tree of Africa harbors great economic potential. Acceptance of marula-derived products internationally will directly increase the demand for marula resource. Rapid multiplication of marula trees of superior quality forms the basis of sustainable export growth. In vitro propagation and genetic improvement offer the opportunity for accelerated multiplication of selected tree material as well as to dramatically increase production, quality and efficiencies. The objectives of the study were therefore to develop a protocol for in vitro multiplication of marula and to determine the feasibility of Agrobacterium-mediated transformation of the marula tree. Nodal sections with axillary bud (s) were cultured on Murashige and Skoog (MS) medium supplemented with 4.8μM BA and 2.4μM KN and 0.1% polyvinylpyrrolidone (PVP) to obtain on average 2.5 microshoots per responding explant. The proliferated microshoots were elongated on MS medium supplemented with 1.2μM BA and 1.0μM KN. Elongated microshoots were rooted in MS medium at half salts strength supplemented with 10μM IBA and 0.3% activated charcoal (AC). On average 82% of the shoots rooted. Survival of acclimatized plantlets was 90%. RAPD analysis confirmed intraclonal genetic stability between parent plants and their clones within the limits of the technique.Nodal sections cocultivated with Agrobacterium tumefaciens for 3 days on MS multiplication medium supplemented with 100μM acetosyringone resulted on average in transient expression of 52.5% of the explants with 1.6 blue stained zones per explant. Cocultivated explants on MS selection medium containing 300mgl-1 kanamycin resulted in 1.5% chimeric putative transgenic shoots. This is the first report on the micropropagation and genetic transformation of marula, Sclerocarya birrea subsp caffra.
South Africa’s National Research Foundation Institutional Research Development Program (NRF-IRDP)

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Cameron, Emilie C. "Fruit Fly Pests of Northwestern Australia." University of Sydney, 2007. http://hdl.handle.net/2123/1711.

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Doctor of Philosophy(PhD),
Until recently, Northwestern Australia was thought to be relatively free of serious fruit fly pests. Although a noxious strain, present in Darwin since 1985, was widely believed to be an infestation of the Queensland fruit fly, Bactrocera tryoni, from the East coast, the fruit flies present outside this area were believed to be the benign endemic species, B. aquilonis. However, during the year 2000, infestations of fruit flies were discovered on major commercial crops in both Western Australia and the Northern Territory. It was not known whether these outbreaks were due to an invasion of the major pest species, Bactrocera tryoni, a change in the behaviour of B. aquilonis, or a hybridisation event between the two species. Finding the source of these outbreaks has been complicated by the fact that, since B. tryoni and B. aquilonis are virtually indistinguishable morphologically, it was not known which species are present in the region. Traditionally any tryoni complex fly caught in the Northwest was called B. aquilonis based solely on location. In order to get a good population profile of the region, an extensive trapping program was set up to include flies from urban areas, commercial crops and natural areas where the benign strain is thought to remain. Tests of genetic differentiation and clustering analyses revealed a high degree of homogeneity in the Northwest samples, suggesting that just one species is present in the region. The Northwest samples were genetically differentiated from the Queensland samples but only to a small degree (FST =0.0153). MtDNA sequencing results also showed a small degree of differentiation between these regions. A morphological study of wing shape indicated that there are some minor identifiable morphological differences between East coast and Northwest laboratory reared flies. This difference was greater than that seen between B. jarvisi populations across the same geographic range. The results suggest that the flies caught in the Northwest are a separate population of B. tryoni. Soon after pest flies were discovered in Darwin, a population became established in Alice Springs. This population had a low genetic diversity compared with Queensland and Darwin populations, and showed evidence of being heavily founded. In 2000, an outbreak was discovered in the nearby town of Ti Tree. Due to the geographic and genetic similarity of these populations, Alice Springs was determined to be the source of the Ti Tree outbreak. To investigate the founding of these populations, a program was developed to estimate the propagule size. Using a simulation method seven different statistics were tested for estimating the propagule size of an outbreak population. For outbreaks originating from populations with high genetic diversity, the number of alleles was a good estimator of propagule size. When, however, the genetic diversity of the source population was already reduced, allele frequency measures, particularly the likelihood of obtaining the outbreak population from the source population, gave more accurate estimates. Applying this information to the Alice Springs samples, it was estimated that just five flies were needed to found the major population in and around Alice Springs. For Ti Tree, the propagule size was estimated to be 27 flies (minimum 10). In 2000, a much larger outbreak occurred in the developing horticultural region of Kununurra in northern Western Australia. An important question for the management of the problem is whether there is an established fly population or the flies are reinvading each year. This population was found to have a large amount of gene flow from the Northern Territory. Within the Kununurra samples, one group of flies was genetically differentiated from all the other samples. This group came from a small geographic area on the periphery of Kununurra and appeared to be the result of an invasion into this area at the time when the population was building up following the dry season. A further threat to the Northwest horticultural regions comes from B. jarvisi. A recent increase in the host range of this species has lead to speculation that it may become a greater pest in Northwestern Australia. At the present time, protocols for the population monitoring and disinfestation of this species are not in place. Here it is shown that B. jarvisi eggs are more heat tolerant than B. tryoni eggs and that monitoring of B. jarvisi populations is possible using cue lure traps placed according to fruiting time and location of their favoured host, Planchonia careya.

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Arias, Mella Maria Belen. "Global and local population genetics of the Mediterranean fruit fly, Ceratitis capitata, an invasive pest of fruit crops." Thesis, Imperial College London, 2018. http://hdl.handle.net/10044/1/64776.

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Invasive species are recognised as one of the most important, growing threat to food biosecurity, causing a significant economic loss in agricultural systems. Despite their damaging effect, they are attractive models for the study of evolution and adaptation in newly colonised environments. Currently, the global climate represents one key potential stressors to impact the food biosecurity because of its influence in the distribution and change in the abundance of agricultural pests. The tephritid fruit flies (Diptera: Tephritidae) contain some of the most successful invaders and most devastating agricultural pests recognised worldwide. Among them, the Mediterranean fruit fly Ceratitis capitata and the South American fruit flies in the genus Anastrepha are particularly important for crop production. Insecticides have been used extensively for their control. This thesis investigates factors that are related to invasiveness in these species, in order to provide novel information that will ultimately improve management control methods. First, environmental niche modelling was used to determine the influence of climate change in the potential habitat distribution of C. capitata, predicting both polewards expansion as well as greater connectivity. Next, historical global dispersal patterns of the medfly over the past two centuries were investigated using molecular and genetic approaches. In Chapter 4, different attempts to identify the point mutation G328A Ccace2 gene that confers resistance to insecticides were assessed at local and intercontinental scale, in part by studying museum specimens from before and after the use of pesticides. Additionally, to improve genetic knowledge of this invasive species, the mitogenome of different species of Anastrepha were sequenced and analysed together with others tephritid. This investigation provides crucial information revealing the evolutionary factors that influence the medfly’s successful invasions and will contribute to the development of evidence-driven pest management protocols, especially in the Americas, including the choice among different control methods as well as the establishment of quarantine procedures to interrupt colonisation routes.

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Hoogwerf, A. M. "The genetics of a small autosomal region of Drosophila melanogaster, including the structural gene for larval serum protein two." Thesis, University of Oxford, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.370260.

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Ribeiro, Serra Octávio Manuel. "Towards increasing genetic variability and improving fruit quality in peach using genomic and bioinformatic tools." Doctoral thesis, Universitat Autònoma de Barcelona, 2017. http://hdl.handle.net/10803/460882.

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El préssec és un dels fruiters més conreats al món, la producció del qual s’ha duplicat en els darrers vint anys. Per augmentar el seu consum cal millorar-ne la qualitat, un repte difícil ja que es tracta d’una fruita de curta vida postcollita. Addicionalment, el préssec te poca variabilitat genètica el que implica que les seves possibilitats de millora genètica són limitades. Altres elements que condicionen el futur del conreu del préssec son el canvi climàtic, la globalització del mercat i els canvis d’hàbits alimentaris dels consumidors. Per a encarar aquests reptes caldrà implementar noves estratègies per a explotar millor la variabilitat existent dins l’espècie i per a introduir nous gens d’altres espècies silvestres o conreades properes, que son els objectius d’aquesta tesi. Primer, vam estudiar la base genètica del caràcter de maduració lenta del fruit (SMF), la carn del qual es manté ferma més temps que la carn tova (MF) que actualment domina el mercat, el que resulta en una vida postcollita més llarga. La referència pel caràcter SMF a Espanya és la varietat de nectarina ‘Big Top’, que es va usar per a generar dues descendències F1 amb pares MF. Vam construir mapes genètics d’alta densitat amb SNPs i vam mesurar el caràcter SMF en ambdues descendències. Els dos loci de caràcters quantitatius (QTLs) trobats colocalitzaren amb dos QTLs d’època de maduració en els grups de lligament 4 (G4) i G5, explicant >20% de la variabilitat fenotípica observada cadascun. El QTL del G5 només es trobà a ‘Big Top’ i és possiblement el causant principal del seu comportament SMF. En segon lloc, assajarem una nova estratègia, que anomenàrem introgressió assistida amb marcadors (MAI), per a introduir nova variabilitat d’origen exòtic en espècies llenyoses en un curt període de temps - dues generacions després de l’híbrid - usant marcadors moleculars per a accelerar el procés. Como resultat lateral vam desenvolupar un joc de línies d’introgressió (ILs) d’ametller en el fons genètic del presseguer, una eina útil per a l’anàlisi genètica de caràcters d’herència complexa. Finalment, estudiàrem el procés de recombinació usant dades de reseqüència d’ADN dels descendents d’un encreuament entre un híbrid ametller × presseguer i el seu genitor masculí (el presseguer ‘Earlygold’), el que permeté comparar la recombinació inter i intraespecífica. Entendre quins factors controlen la formació dels entrecreuaments (COs) és essencial pel control de la introgressió d’un donant exòtic al germoplasma cultivat. Desenvolupàrem un programa bioinformàtic per a detectar SNPs i indels, genotipàrem in silico cada individu i determinàrem la posició dels COs. Un primer resultat fou una distribució heterogènia de COs al genoma, però semblant en meiosis intra i interespecífiques, encara que la recombinació interespecífica va ser molt menys freqüent que la intraespecífica. Localitzàrem les regions dels COs i en vam trobar algunes amb més COs dels esperats (hotspots), detectant motius d’ADN associats a aquestes regions. Altres esdeveniments de recombinació anomenats “noncrossovers” es van detectar a la meiosi de l’híbrid a una freqüència aproximadament cinc vegades més alta que la dels COs. Finalment, associàrem la baixa recombinació en l’híbrid amb la baixa fertilitat del seu pol·len, indicant que la diversitat de seqüència del ADN es una possible causa d’aïllament reproductiu en plantes. En conjunt, els nostres resultats proporcionen informació nova sobre l’herència de caràcters clau per a la millora del presseguer, eines per a l’anàlisi fi de caràcters d’herència complexa, una estratègia de millora per a la introgressió de gens d’interès procedents d’altres espècies i dades sobre el funcionament de la recombinació interespecífica. Al mateix temps, hem produïm informació sobre eines moleculars que permeten aplicar aquests coneixements a l’obtenció de varietats millorades.
Peach is a major fruit species, cultivated worldwide, with an outstanding adaptation to contrasting climate conditions, which world production has doubled in the last two decades. Increasing peach consumption requires enhancing fruit quality, a challenging objective for a fruit that has a short postharvest life. An important shortcoming for peach breeding is its low level of variability, narrowing the possibilities for its improvement. Other elements that may further condition peach production and breeding are climate change, the globalization of peach market and the changing eating habits of the population. Facing these challenges requires implementation of new strategies allowing a better exploitation of the variability that still exists inside the species and the introduction of new variability using other cultivated or wild relatives. In this work we aim to contribute in the development of such novel approaches. First we studied the genetic basis of the slow melting flesh (SMF) trait, characterized by the longer postharvest life of fruits, with higher firmness values after harvest than regular melting flesh (MF) peaches. SMF is present in some North American peach and nectarine cultivars, one of which (‘Big Top’), has become a reference for nectarine production in Spain. We studied two F1 populations using ‘Big Top’ as female parent, built linkage maps using the 9k peach SNP chip, and measured SMF. Quantitative trait loci (QTL) analysis allowed us to find two consistent QTLs for SMF co-localizing with maturity date QTLs in linkage group four (G4) and G5 that explained each >20% of phenotypic variability. The QTL on G5 was exclusive to ‘Big Top’, which can be the cause of its specific SMF behavior. In a second topic, we tested a new strategy, marker assisted introgression (MAI), to introduce new variability from exotic sources into cultivated perennial species in a short timeframe, using molecular markers to accelerate the process. As a side result we developed a set of introgression lines (ILs) of almond in the genetic background of peach, an optimal tool for genetic analysis of complex traits. In the final topic of this thesis we aimed to study the recombination process in wide crosses (almond × peach) in comparison with that of intraspecific crosses (peach), using resequence data of a cross between an almond × peach hybrid and its peach parent (‘Earlygold’). Understanding which factors control the occurrence of crossovers (COs) is critical to control the introgression process from an exotic donor to elite cultivated materials. We developed a bioinformatics pipeline to detect SNP and indel variants, in silico genotyped each individual, and determined the CO positions using the variants called. We found that the distribution of COs was heterogeneous in the genome, but similar in intra and interspecific meioses, and that a strong reduction of recombination occurred at the interspecific level, which we associated with DNA sequence divergence. We studied the CO regions, found some with high CO frequency (hotspots) and identified DNA motifs associated with these regions. Other recombination events such as noncrossovers (NCOs) were also detected for the hybrid meiosis about five times more frequently than COs. Finally, we associated low recombination in the hybrid with low pollen fertility, suggesting DNA sequence divergence as a possible cause for a gradual process of reproductive isolation in plants. Overall, our results supply new information on the inheritance of key commercial peach traits, tools for the fine analysis of complex characters, a breeding strategy for the enrichment of peach genome with valuable genes from other species, and data on how interspecific recombination proceeds. At the same time, we provide molecular tools to facilitate the translation of this knowledge into new and improved cultivars.

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Walley, Peter Glen. "Dissecting the genetic regulation of texture traits in tomato fruit." Thesis, University of Warwick, 2007. http://wrap.warwick.ac.uk/2291/.

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The aim of the work presented in this thesis was to assess the genetic variation present within the wild tomato species Solanum pennellii that can be adapted to improve the texture of the domesticated tomato species. Using a population of S. pennellii introgression lines, 23 significant QTL supporting intervals were identified. Nine of the QTL were significant in two growing seasons. Three QTL were identified for pericarp firmness. Lines containing the firmness QTL F-Sp 2.1 were used to create BC1 populations. Sensory analyses were used to correlate the instrumental texture measurements to those perceived during mastication. Repeated texture measurements were conducted on lines representing similar chromosomal regions from another wild tomato species Solanum habrochaites introgression line population. To better understand the genetic basis of one of the firmness QTL identified, the Syngenta tomato Affymetrix GeneChip was used to quantify the differential expression of S. pennellii genes within the QTL-introgression line through development in comparison to the recurrent parent S. lycopersicum L. cv M82. The microarray analyses were extended to the ripening mutants Cnr, nor and rin. Differential gene expression between the ripening mutants and the wild type Ailsa Craig were compared through development. Candidate genes for the firmness QTL and fruit development were nominated.

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Bakar, Umi Kalsom Abu. "Characterisation of a ripening-related cDNA clone form Lycopersicon esculentum." Thesis, University of Nottingham, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.260617.

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Exley, Katherine Ann. "Structure, frequency and distribution of P elements in relation to P-M hybrid dysgenesis in Drosophila melanogaster." Thesis, University of Liverpool, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.279706.

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Cripps, Richard Matthew. "Genetical and biochemical studies of Drosophila indirect flight muscles." Thesis, University of York, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.276490.

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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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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.

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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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Smith, Christine Mary. "Genetic variation for fruit development of Pisum sativum L., with special reference to the effects of the rugosus locus." Thesis, University of Plymouth, 1986. http://hdl.handle.net/10026.1/2266.

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This study has compared various aspects of pea fruit development, using two green-podded lines near-isogenic except for the r locus and a yellow-podded mutant having the genotype gpgp. The gp gene is associated with reduced chlorophyll in the pod wall which then appears yellow. The r gene is associated with a wrinkled appearance of mature dried seed and cotyledonary starch grains which are small and fissured. An ultrastructural survey of tissues from pods, testas and cotyledons showed there to be no effect of the r locus on chloroplast structure. The structure of amyloplasts however, appeared to be affected by the r locus; starch grains in the cotyledons having a rugged outline in the wrinkled type. Chloroplasts from the inner tissues of the yellow pod were similar to those in leaves, green pods, green-podded testas and cotyledons. Chloroplasts in the yellow pod mesocarp and in the testa of yellow pods had dilated thylakoids, less starch and more lipid than the green-podded types. Growth analysis of the near-isogenic lines showed there to be no difference between the round (RR) and wrinkled (rr) lines in pod and testa growth, but embryo growth differed. The wrinkled embryo contained more water during development but had a lower final dry weight than the round embryos. Water potential (an indication of the osmotic regulation) was lower in the wrinkled embryos than in the round embryos, except very early in development when it was higher in the wrinkled embryos. In vitro culture of embryos showed that optimum growth was obtained in liquid media containing 10% sucrose as a carbon source. Replacing sucrose with mannitol determined that it was the sucrose which was important, not its resulting water potential. These gp and r gene effects and their relevance to future breeding programmes are discussed with other biochemical studies on similar genotypes.

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Markey, Adrienne Selina, and n/a. "The evolution of fruit traits in Coprosma and the subtribe Coprosminae." University of Otago. Department of Botany, 2006. http://adt.otago.ac.nz./public/adt-NZDU20061206.160155.

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The flora of New Zealand has evolved largely in the absence of terrestrial mammals, the predominant frugivore guilds being birds and reptiles. The evolution of divergent fruit traits in New Zealand may be a consequence of different selection pressure by these two guilds, and two contrasting putative dispersal syndromes have been proposed for New Zealand fleshy fruited plants. Coprosma (Rubiaceae: subtribe Coprosminae) is a speciose and morphologically diverse genus, which is distributed throughout the South Pacific and which also produces variably coloured drupes. It was selected as a model genus to investigate the evolution of fruit traits within this context. For this purpose, a molecular phylogeny for the subtribe Coprosminae and Coprosma was inferred using parsimony, likelihood and split decomposition analysis on sequences from the 16rps intron of cpDNA and ETS and ITS region of nrDNA. Up to 32 species were included in the subtribal analyses, whilst 53 species of Coprosma were used in subgeneric studies. The basis for the variety of fruit colours seen in New Zealand was determined using histology and pigment extractions. To test the assumption that fruit traits among species evolved in concert under selection from frugivore guilds, fruit shape, size and nutrient composition were determined in order to test predictions that these would co-vary with fruit colour. In the Coprosminae, fleshy drupes have arisen from dry fruited schizocarps and with two possible reversals to semi-dry drupes. Within Coprosma, fruit colour was found to be evolutionarily labile and varied both among and within lineages, particularly within two main groups where fruit colour had shifted from orange to blue and white, or red, pink and black colours respectively. The evolution of novel (non-orange) fruit colours was restricted to New Zealand, as was the small-leaved, divaricate growth form, the combination of which has been associated with a putative reptile dispersal syndrome. Several trans-oceanic dispersals out of New Zealand were also inferred from the phylogeny, these extending into Australia, New Guinea and Hawai�i. In these instances, fruit colour did not appear change markedly after establishment in a new country. Within New Zealand, fruit sizes were found to vary with colour as predicted, although the majority of species produced small (< 8 mm), elliptical fruits. There was no clear association between fruit colour and fruit nutrient composition. It would appear that these small, succulent, carbohydrate-rich and lipid-poor fruits cater to a wide range of generalist frugivores. The variety of fruit colours in Coprosma stemmed from qualitative and quantitative differences in carotenoid and anthocyanin composition. The genetic basis for the control of these pathways is currently unknown, but it is assumed that a few regulatory genes can control a substantial amount of phenotypic variation. Considering the evolutionary history of Coprosma, it would appear that a history of recent and rapid speciation, hybridisation and reticulate evolution may have increased the tempo of fruit colour evolution in the genus.

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Chadburn, R. G. "An investigation into the genetics and ecology of a closed semi-natural population of Drosophila melanogaster." Thesis, University of Liverpool, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377122.

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Pereira, García Lara. "Genetic dissection of fruit quality and ripening traits in melon." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/663830.

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El melón (Cucumis melo L.) es un importante cultivo a nivel mundial, con una producción de 31 millones de toneladas durante el año 2016. Aunque tradicionalmente los programas de mejora genética se han focalizado en el comportamiento agronómico del cultivo, la calidad de fruto se ha convertido recientemente en un objetivo principal. La calidad del fruto es un concepto complejo, que incluye diversos caracteres relacionados con la apariencia visual del fruto y su calidad nutricional y organoléptica. Muchos de estos caracteres están asociados a la maduración de fruto, que es el proceso que sufre el fruto para transformarse en un alimento atractivo para promover la dispersión de la semilla. Los frutos son clasificados, en base a su comportamiento durante la maduración, en climatéricos, cuando la hormona vegetal etileno es sintetizada de manera autocatalítica al comienzo del proceso de maduración, y no climatéricos, para los cuales el etileno no tiene un papel importante. El principal objetivo de este trabajo ha sido estudiar las bases genéticas de la calidad y la maduración del fruto en melón. Hemos desarrollado una población de líneas puras recombinantes (RIL) a partir del cruce entre dos variedades élite, “Védrantais”, altamente climatérica, y “Piel de Sapo” (PS), no climatérica. La diversidad fenotípica en la calidad de fruto y los caracteres asociados a la maduración, incluyendo la producción de etileno, han sido estudiados en profundidad. Un mapa genético de alta densidad ha sido construido usando variantes obtenidas a través de un experimento de genotyping-by-sequencing. Un experimento de mapeo de QTLs reveló cinco genes mayores y 33 QTLs implicados en la apariencia visual del fruto (color, presencia de suturas, moteado), morfología de fruto, contenido en azúcares y peso de semilla. Un segundo experimento de mapeo de QTLs identificó 14 QTLs implicados en la producción de etileno y otros caracteres asociados a la maduración, como degradación de clorofila o formación de una capa de abscisión. Entre ellos, podemos destacar un QTL mayor, ETHQV8.1, implicado en la producción de etileno que afectó a prácticamente todos los caracteres estudiados, localizado en un intervalo de 500 kb del cromosoma VIII. Para diseccionar genéticamente la maduración del fruto, además de la mencionada población de RILs, estudiamos la línea casi isogénica (NIL) climatérica 8M35, con el fondo genético de PS y una introgresión de la accesión exótica PI 161375. 8M35 porta el QTL ETHQB3.5, delimitado en una región de 5Mb del cromosoma III. Se ha seguido una estrategia de clonaje posicional para el mapeo fino de ETHQB3.5, generando un juego diverso de subNILs. Tras múltiples evaluaciones de diferentes subNILs, determinamos que al menos dos factores genéticos diferentes deben estar implicados en el desencadenamiento de la maduración climatérica en la línea 8M35. Uno de ellos, nombrado ETHQB3.5.1, es responsable de la mayor parte del fenotipo y fue delimitado a una región de 500 kb que contiene 63 genes anotados. Finalmente, dos colecciones de introgresiones recíprocas fueron desarrolladas, utilizando “Védrantais” y PS, ambos como líneas parentales recurrente y donante, respectivamente. Se efectuaron retrocruzamientos recurrentes en las dos direcciones y se realizó una selección asistida por marcadores en cada generación, para seleccionar tanto la introgresión diana como el fondo genético deseado. Las colecciones actuales, que cubren el 95% del genoma de la línea parental donante, están formadas por 38 líneas de introgresión. Hemos realizado un fenotipado preliminar que ha permitido validar algunos de los QTLs mapeados en la población de RILs. Además, dos familias segregantes de líneas de introgresión con el fondo genético de PS se han usado para el mapeo fino de ETHQV8.1, permitiendo reducir la región a un intervalo de 150 kb que contiene 14 genes candidatos.
Melon (Cucumis melo L.) is an important crop worldwide, with a production of around 31 million tons during 2016. Although traditionally breeding programs have been focused on agronomic traits, fruit quality has become a main goal recently. Fruit quality is a complex concept, including diverse traits related to fruit appearance, nutritional and organoleptic traits. Many of these traits are associated to fruit ripening, which is the process that the fruit undergoes to become edible to promote seed dispersal. Fruits are classified according to their ripening behavior into climacteric, when the plant hormone ethylene is synthesized in an autocatalytic way at the onset of ripening, and non-climacteric, in which ethylene has not a major role. The main goal of this work was to study the genetic basis of fruit quality and fruit ripening in melon. We have developed a Recombinant Inbred Line (RIL) population from a cross between two elite cultivars, “Védrantais”, highly climacteric, and “Piel de Sapo”, non-climacteric. The phenotypic diversity in fruit quality and ripening-associated traits, including ethylene production, has been thoroughly studied. A high-density genetic map was constructed using SNPs and INDELs obtained through a genotyping-by-sequencing experiment. A first QTL mapping experiment revealed five major genes and 33 QTLs governing fruit appearance (flesh and rind color, presence of sutures, mottled rind), fruit morphology, sugar content and seed weight. A second QTL mapping experiment identified 14 QTLs modifying ethylene production and ripening-associated traits, as chlorophyll degradation and abscission layer formation. Among them, we highlight a major QTL, ETHQV8.1, involved in ethylene production that was affecting almost all the studied traits, located in a 500-kb interval in chromosome VIII. In order to genetically dissect the fruit ripening process in melon, in addition to the mentioned RIL population, we studied a climacteric near-isogenic line, 8M35, with “Piel de Sapo” background and containing an introgression from the exotic accession PI 161375. 8M35 carries a QTL, ETHQB3.5, delimited in a region of 5 Mb in chromosome III. A positional cloning strategy was followed to fine map ETHQB3.5, generating a diverse set of subNILs. After multiple evaluations of different subNILs, we determined that at least two different genetic factors should be involved in triggering climacteric ripening in 8M35. One of them, named ETHQB3.5.1, which is responsible for the major part of the variation, was delimited to a 500-kb region containing 63 annotated genes. Finally, two reciprocal introgression line (IL) collections were developed, using both “Védrantais” and “Piel de Sapo” as recurrent and donor parental lines, respectively. Recurrent backcrosses were performed in both directions and marker-assisted selection was performed in each generation to select both the target introgressions and the desired background. The current IL collections, covering approximately 95% of the donor parental genome, are formed by 38 ILs. We performed a preliminary phenotyping that allowed to validate some of the QTLs mapped in the RIL population for both fruit quality and fruit ripening traits. In addition, two segregating families of ILs with “Piel de Sapo” background were used to fine map ETHQV8.1, allowing to narrow down the region to a 150-kb interval containing 14 candidate genes. As a summary, this PhD thesis has contributed to improving our knowledge about the genetics of fruit quality and particularly fruit ripening in melon, proposing some important QTLs that will be further explored in the future. Our work suggests that climacteric behavior in melon is a complex and quantitative trait controlled by polygenic inheritance, rather than a qualitative class as described traditionally in the literature.

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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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22

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.

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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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Cabrera, Antonio. "Genetic Analysis and Fruit weight QTL fine mapping in Sweet cherry (Prunus avium L.)." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1313531104.

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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.

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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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Morgan, Megan Jayne. "Identification of molecular-genetic determinants of quality traits of tomato fruit." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:662d8b1e-70cf-44fb-9ed3-46dcacc39bad.

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Tomato is an important food crop and a model for fleshy fruit development. The process of fruit ripening involves changes in chemical composition and in particular the accumulation of sugars, organic, amino acids and carotenes. The research described in this thesis aimed to identify key regulatory aspects associated with the accumulation of the major acids in tomato fruit by analysis of introgression lines resulting from a cross between a cultivated variety, Solanum lycopersicum, and a wild progenitor species, Solanum pennellii. Line 2-5 showed increases in citrate, malate, aspartate and glutamate in fruit grown under greenhouse conditions. The genetic differences between line 2-5, its overlapping lines, sub-introgression lines and the recurrent parent were used to link the metabolite phenotypes to smaller chromosomal regions. This analysis suggested multiple epistatic loci control fruit metabolite accumulation. Investigation of the biochemical differences between line 2-5 and the recurrent parent revealed that organic and amino acid accumulation did not dependent upon increased TCA cycle capacity. Regulation at the metabolic level was identified for citrate accumulation with changes in cytosolic aconitase in line 2-5. As these metabolites accumulate in the vacuole, tonoplast transport was investigated. Correlation of ATPase-dependent malate influx with altered malate content suggested malate tonoplast transport plays a role in malate accumulation and highlights the importance of vacuolar storage and transport in the regulation of organic and amino acid accumulation.

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Fan, Rong, and 樊榮. "The roles of 1-aminocyclopropane-1-carboxylate synthase isogenes in the flower and fruit development in tomatoes." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40203906.

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Zhang, Na. "Fine Mapping and Characterization of fw3.2, One of the Major QTL Controlling Fruit Size in Tomato." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1332519563.

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Musseau, Constance. "Towards the identification and characterization of new regulators of fruit tissue morphology." Thesis, Bordeaux, 2018. http://www.theses.fr/2018BORD0355.

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La taille du fruit et la morphologie des tissus du fruit sont des caractères clés définissant la qualité finale du fruit. Parmi la grande diversité de fruits observée dans la nature, la domestication et la sélection ont entrainé d’importantes modifications de la taille et de la morphologie des tissus du fruit. Jusqu'à présent, seuls quelques régulateurs génétiques ont été identifiés, et les mécanismes cellulaires et moléculaires par lesquels la morphologie des tissus du fruit est définie restent imprécis. Dans ce contexte, l'objectif de ma thèse est d'identifier et de caractériser de nouveaux régulateurs impliqués dans la morphologie des tissus du fruit. Pour cela, j'ai utilisé une collection de mutants EMS de tomate comme source de diversité génétique et phénotypique et j'ai sélectionné deux mutants présentant des tendances opposées et extrêmes d'épaisseur du péricarpe. Grace à une stratégie de cartographie par séquençage, j’ai identifié une région génétique du chromosome 10, associée au phénotype péricarpe épais. J'ai également étudié le rôle de la Guanylate Binding Protein (GBP) à l’origine du phénotype péricarpe fin chez la tomate. La GBP est une grosse GTP binding protein qui n’a jamais été caractérisée chez les plantes. Afin d'approfondir l’étude de cette protéine, j'ai étudié en parallèle son rôle dans les modèles tomate et Arabidopsis" thaliana. J'ai démontré que les deux protéines homologues sont localisées dans le noyau. La mutation de la GBP chez la tomate induit de fortes altérations de la division et de l'expansion cellulaire à l'intérieur du péricarpe ainsi qu'une altération de la croissance des racines latérales chez la tomate et Arabidopsis, une caractéristique classiquement retrouvée chez les mutants altérés dans la mitose. Cette étude suggère que le GBP joue un rôle dans le contrôle précis des divisions cellulaires dans le péricarpe de tomate
Fruit size and morphology are key characters defining the final fruit quality. Among the large fruit diversity observed in the nature, human domestication and selection has induced changes in fruit size and tissue morphology. Only a few genetic regulators have been identified so far, thus cellular and molecular mechanisms by which fruit tissue morphology is defined remain incomplete. In this context, the aim of my thesis is to identify and characterize new regulators of fruit tissue morphology. For this purpose, I used a collection of tomato EMS mutants as a source of genetic and phenotypic diversity. I selected two mutants presenting opposite trends of pericarp thickness. Through a mapping-by-sequencing strategy, I identified a genetic region on chromosome 10, associated with an extreme thick pericarp phenotype. I also investigated the role of the Guanylate Binding Protein (GBP) at the origin of a thin pericarp phenotype. The GBP is a large GTP binding protein that was never characterized in plants so far. In order to go deeper into its functional characterization in plants, I studied in parallel the role of the protein in tomato and Arabidopsis "thaliana" models. I showed that both homolog proteins are localized at the nucleus. Mutation of GBP in tomato induced strong alterations in cell division and cell expansion inside the pericarp and altered lateral root growth in tomato and Arabidopsis, a classical feature for mutants impaired in mitosis. This study suggests a role for the GBP in the fine control of cell division in the tomato pericarp

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Karsten, Minette. "Population genetics of the Mediterranean fruit fly Ceratitis capitata in the Western Cape Province, South Africa : invasion potential and dispersal ability." Thesis, Stellenbosch : Stellenbosch University, 2011. http://hdl.handle.net/10019.1/18119.

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Thesis (MSc)--Stellenbosch University, 2011.
ENGLISH ABSTRACT: The Mediterranean fruit fly (medfly), Ceratitis capitata, is a highly invasive species throughout the world and considered as one of the most successful agricultural and economical pests. The increase of global trade in fruit and human travel combined with the biology of the medfly has allowed the species to spread from its proposed Afrotropical origin, to a number of locations throughout the world. In the Western Cape various control strategies have been implemented to control medfly populations, including insecticides and more environmentally-friendly techniques such as the Sterile Insect Technique (SIT). In order to be effective, however, an SIT program requires some knowledge of the population structure and the movement of individuals between pest-occupied sites. The identification of sites from which re-invasion is most likely to occur and knowledge regarding the primary routes through which pests are likely to re-establish are critical to ensure successful SIT programmes. To provide this important information to SIT and area-wide pest control programs in South Africa, sampling at two different spatial scales (regional- and fine-scale) in South Africa was undertaken. Regional scale sampling was done at 13 locations in the Western Cape and fine scale sampling was done at 13 locations within the Ceres-valley. All individuals were genotyped at 11 polymorphic microsatellite markers and selected individuals from the regional scale were sequenced for the mitochondrial gene COI. Our results show that populations at regional- and fine-scale in the Western Cape are characterized by high levels of genetic diversity (HEregional = 0.805; HEfine = 0.803). Little or weak population differentiation was detected at the regional- and fine-scales, suggesting overall high levels of gene flow among sampling locations. These findings were supported by coalescent based methods indicating sufficient levels of gene flow to prevent population differentiation between neighbouring (200m) and distant (350km) populations. However, natural dispersal in C. capitata has been shown to rarely exceed 10 km. As such, high levels of gene flow between distant populations are more likely the result of humanmediated dispersal, linked to the movement of fresh produce within South Africa. This high level of gene flow has important implications for pest management practices, as my results suggests that area-wide pest management should be undertaken at a regional scale, rather than on a farm or valley scale. My results are placed within a management framework, and I argue for more stringent control when fruit are transported within South Africa. Of particular interest for future studies is the investigation of gene flow at broader spatial scales (i.e. the whole of South Africa) and a comparison of the genetic diversity, population differentiation and gene flow patterns of C. capitata with that of Ceratitis rosa will be important to establish a successful pest management strategy in South Africa.
AFRIKAANSE OPSOMMING: Die Mediterreense vrugtevlieg (medvlieg), Ceratitis capitata, is ‘n indringerspesie wêreldwyd en word beskou as een van die mees suksesvolle ekonomiese en landbou peste. Die medvlieg het ‘n Afrotropiese oorsprong, maar die toename in wêreldwye handel en reis, gekombineer met die biologie van die medvlieg het gelei tot die verspreiding van die spesie na ‘n groot aantal bestemmings regoor die wêreld. Die Wes-Kaap provinsie van Suid-Afrika implementeer tans verskeie strategieë om medvlieg bevolkings te beheer. Hierdie strategieë sluit in die gebruik van plaagdoders sowel as meer omgewingsvriendelike tegnieke soos die Steriele Insektegniek (SIT). Om ‘n effektiewe SIT program te implementeer vereis basiese kennis ten opsigte van die genetiese struktuur van die bevolking sowel as van die beweging van individue tussen verskillende pesvoorkomsgebiede. Die identifisering van areas van waar herkolonisering mees waarskynlik kan plaasvind en kennis in verband met die primêre roetes waardeur pes spesies hervestig, is van kritiese belang om ‘n suksesvolle SIT program te verseker. Medvlieg individue is op twee verskillende ruimtelike skale (streeks- en plaaslike-skaal) versamel om die nodige inligting aan SIT en area-wye pes beheer programme in Suid-Afrika te verskaf. Streeks-skaal individue is by 13 lokaliteite regoor die Wes-Kaap versamel en plaaslike-skaal individue by 13 lokaliteite in die Ceres-vallei. Alle versamelde individue is vir 11 polimorfiese mikrosatelliet merkers gegenotipeer en DNS volgordebepaling van geselekteerde individue vanuit die streek-skaal is gedoen vir die mitochondriale geen COI. My resultate toon dat bevolkings op beide skale gekarakteriseer word deur hoë vlakke van genetiese diversiteit (HEstreeks = 0.805; HEplaaslik = 0.803) en geen of swak bevolkings differensiasie. Hierdie resultate dui daarop dat daar hoë vlakke van geenvloei tussen bevolkings is. Hierdie bevindinge word verder ondersteun deur metodes gebaseer op die statistiese eienskappe van die genealogiese verhouding tussen allele onder sekere mutasie en demografiese modelle, wat voldoende vlakke van geenvloei aandui tussen nabye (200m) sowel as verafgeleë (350km) bevolkings om bevolkings differensiasie te verhoed. Natuurlike beweging in C. capitata is egter selde meer as 10 km, sodanig kan die hoë vlakke van geenvloei toegeskryf word aan die verspreiding van individue met menslike hulp, spesifiek in die vervoer van varsprodukte in Suid-Afrika. Hierdie hoë vlak van geenvloei het verreikende implikasies vir pes beheer praktyke, omdat my resultate voorstel dat area-wye pes beheer onderneem moet word op ‘n streeks-skaal eerder as op ‘n plaas-tot-plaas of vallei wye area. Ek plaas my resultate in ‘n bestuursraamwerk, waarin ek streng beheer van vrugtevervoer in Suid-Afrika beklemtoon. Verdere navorsing moet fokus op die ondersoek van geenvloei op ‘n landswye skaal (hele Suid-Afrika) in C. capitata, sowel as die vergelyking van die genetiese diversiteit, bevolkings differensiasie en geenvloei patrone van C. capitata met die van Ceratitis rosa om ‘n suksesvolle pes beheer strategie vir Suid-Afrika te formuleer.

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30

Hackney, Erin Elizabeth. "The effects of small population size, breeding system, and gene flow on fruit and seed production in American ginseng (Panax quinquefolius L., Araliaceae)." Morgantown, W. Va. : [West Virginia University Libraries], 1999. http://etd.wvu.edu/templates/showETD.cfm?recnum=1170.

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Thesis (M.S.)--West Virginia University, 1999.
Title from document title page. Document formatted into pages; contains ix, 84 p. : ill. Vita. Includes abstract. Includes bibliographical references.

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Zucchi, Maria Imaculada. "Análise da estrutura genética de Eugenia dysenterica DC utilizando marcadores RAPD e SSR." Universidade de São Paulo, 2003. http://www.teses.usp.br/teses/disponiveis/11/11137/tde-17032003-144316/.

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Os marcadores moleculares têm sido frequentemente utilizados em estudos sobre a diversidade e a estrutura genética populacional. A introdução dos marcadores moleculares revolucionou a genética de populações na década de 50, com a técnica de isoenzimas e recentemente tem conseguido enormes avanços com a aplicação de tecnologias baseadas em DNA. Os marcadores moleculares baseados em DNA permitiram uma ampla cobertura genômica e tornaram-se poderosas ferramentas para estudos de genética de populações. Marcadores codominantes têm sido muito utilizados na genética de populações por serem mais informativos que os marcadores dominantes. O objetivo principal deste trabalho foi utilizar marcadores dominantes com o intuito de contornar o problema da dominância. Para isso, foram utilizadas neste trabalho progênies para genotipagens com RAPD visando inferir o genótipo das plantas matrizes. Foi encontrando um valor de variação entre populações de plantas jovens, igual a ST f =0,328. E estimativa similar a esta, foi calculada com os dados de freqüências alélicas das plantas matrizes, obtendo-se um valor de ST F =0,318. O objetivo secundário deste trabalho foi gerar várias estimativas de parâmetros populacionais com a finalidade de comparar os diferentes tipos de marcadores moleculares. Foram comparadas as estimativas relacionadas ao sistema reprodutivo ( t ), heterozigozidade esperada ( e H ) e observada ( o H ), estatísticas F de Wrigth, o parâmetro ST f e dendrogramas obtidos com os diferentes tipos de marcadores (SSR, RAPD e isoenzimas) em diversas abordagens. A taxa de cruzamento ( t ) obtida com os diferentes tipos de marcadores foram congruentes, sendo que a menor foi encontrada com isoenzimas utilizando progênies ( m t =0,835), e a maior obtida com marcadores SSR ( a t =1,07) utilizando indivíduos adultos. Isto levou a concluir que a espécie é alógama ou com tendência para alogamia. Com relação à estrutura genética e o fluxo gênico as estimativas não foram inteiramente concordantes. A menor estimativa de divergência foi obtida com marcadores isoenzimáticos ( p q =0,154, Nm=1,370) e a maior com RAPD ( ST f =0,328, Nm=0,512). Porém é importante ressaltar, que estas estimativas não são diretamente comparáveis, pois são obtidas de maneiras diferentes e com dados de progênies ou adultos. Quanto à estruturação da variabilidade visualizada através de agrupamentos, observou-se que os dendrogramas apresentam um padrão concordante sendo que a maior sensibilidade (maior amplitude de distâncias) foi obtida com os dados de SSR. Além disso, foram feitas correlações entre as matrizes de distâncias genéticas e geográficas e entre as matrizes de distâncias genéticas (correlações entre os diferentes marcadores). Estas correlações foram altas indicando que todos os marcadores amostram bem o genoma. Este estudo permitiu comparar dados de duas gerações e uma metodologia diferente para análise de dados com marcadores dominantes, sem impor restrições nos modelos (f =1 ou f =0). Pôde-se concluir que houve congruência entre as estimativas dos parâmetros populacionais obtidas com os diferentes tipos de marcadores, embora tenha ocorrido algumas discrepâncias como foi o caso da estimativa de fluxo gênico com marcadores isoenzimáticos. Apesar de os marcadores possuírem diferentes naturezas todos foram igualmente informativos para este estudo populacional, inclusive os dominantes quando foram usados dados de duas gerações.
Molecular markers have frequently been used in studies on diversity and population genetic structure. The introduction of the these markers revolutionized the genetics of populations in the decade of 50 with the isoenzimes technique and recently enormous progresses have been achieved with the application of technologies based on DNA. Molecular markers based on DNA allowed a wide coverage of the genome and therefore became a powerful tool for these studies. Codominant markers, being more informative than the dominant ones are now being widely used. The main objective of this work was to use dominant (RAPD) markers overcomming the problem of dominance through progeny testing. Offspring were genotyped in order to infer the maternal genotype. Using the AMOVA procedure the variation value found among populations of seedlings was equal to ST f =0.328. The corresponding F statistic, based on allelic frequencies of seed parents, was ST F =0.318. The second objective of this work was to obtain different estimates of population parameters with the purpose of comparing the different types of molecular markers. In addition to Wrights F statistics, estimates related to the reproductive system (t ), expected ( e H ) and observed heterozigozities ( o H ) and dendrograms obtained with markers SSR, RAPD and isoenzimes were compared. The outcrossing rate ( t ) obtained agreed reasonably well, and the smallest value was found with isozymes using progenies ( m t =0.835), and the largest one, obtained with SSR markers ( a t =1.07) using adult individuals. The results led to a conclusion that the species is allogamic or with tendency to allogamy. Estimates related with the genetic structure and gene flow, however, were not entirely congruent. The smallest divergence estimate was obtained with isozymes ( p q =0.154, Nm=1.370) and the largest one with RAPD ( ST f =0.328, Nm=0.512). It is important to point out, that these estimates are not directly comparable, due to the difference in the underlying model and the basic material used (progenies or adults). About the structuring of the variability visualized through groupings, dendrograms presented a congruent pattern and the largest sensibility (larger range of distances) was obtained with SSR data. In addition, correlations were calculated among the matrices of genetic and geographical distances and among the matrices of genetic distances obtained from the different markers. High correlations were verified among these matrices, indicating that all markers sampled well the genome under study. This study allowed to compare data of two generations and a different methodology for data analysis with dominant markers, without imposing restrictions on the model ( f =1 or f =0). It could be concluded that a reasonable consistency was verified among the population parameters obtained with different types of markers, although some discrepancies existed as in the case of estimates of gene flow with isozymes markers. In spite of their different origins, the markers used here were equally informative for this population study, including the dominant one, when data of two generations were used.

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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.

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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.

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Chan, Robin. "Genetic Analysis of Ethanol Sensitivity and Tolerance in Drosophila." VCU Scholars Compass, 2013. http://scholarscompass.vcu.edu/etd/3154.

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The genetic pathways influencing alcohol abuse and dependence are poorly characterized. Many critical discoveries about the interactions between ethanol-related behaviors and genetics have been made in the fruit fly Drosophila melanogaster. Coupling the statistical power of model organism studies to human association studies bolsters the analytical efficacy of these genomic approaches. A variety of behavioral assays are available for assessing behavioral responses to ethanol in Drosophila. However, we find our previously described eRING assay is influenced by the commonly used transgenic marker mini-white. We developed a Simple Sedation Assay (SSA) that is insensitive to the effects of white and mini-white. In SSAs, expression of endogenous wild-type white was not necessary for normal responses to ethanol. Neither expression nor RNAi-mediated knockdown of the transgenic mini-white influenced the effects of ethanol in flies. Critically, mini-white expression did not affect the phenotypes of flies with known alterations in ethanol sensitivity. Also, loss of function mutations in Clic show decreased sensitivity to ethanol in both eRING assays (as previously reported) and SSAs. Therefore, we explored the role of the known Clic interactors, TGF-β and ryanodine receptors. These studies were inconclusive but do not exclude the need for future work. Finally, using bioinformatic tools we constructed a mutli-species network of genes predicted to interact with Clic. Our RNAi screen against the Clic network serves as an important proof-of-concept and holds great potential for uncovering important therapeutic targets for alcohol use disorders.

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Peel, Alison Jane. "The epidemiology of Lagos bat virus and henipaviruses in straw-coloured fruit bats (Eidolon helvum), using population genetics to infer population connectivity." Thesis, University of Cambridge, 2012. https://www.repository.cam.ac.uk/handle/1810/244571.

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The straw-coloured fruit bat, Eidolon helvum, has been identified as a reservoir for potentially-zoonotic henipaviruses and Lagos bat virus (LBV) in continental Africa. Longitudinal studies at a large urban colony in Accra, Ghana aim to better understand E. helvum and viral ecology, as well as the nature of human-bat interactions. To assess whether the findings from these studies can be extrapolated across the species’ continental range, more information on the movement ecology of the species and connectivity of populations across its range was required. A multifaceted approach, using techniques from the field of genetics, population ecology, and virology, was used to understand the ways in which the structure and dynamics of fruit bat populations across Africa may affect the viral transmission dynamics within them. Given recent difficulties in using electronic positioning systems on E. helvum to track movement, genetic methods were proposed as the most appropriate way to assess connectivity between populations across such a vast range. Henipavirus and LBV serological analyses were undertaken on samples from 12 populations of E. helvum bats across its continental and offshore-island range. A combination of mitochondrial DNA and microsatellite markers were used to describe the genetic metapopulation structure of E. helvum and data were obtained in each location on population sizes, demographic structure, reproductive and migratory seasonality, as well as bat-human interactions. Consistent with expectations for a vagile migratory species, a panmictic continental population structure was detected across its continental range, although the extent of this panmixia was greater than previously detected in any other mammal or bird. Antibodies to henipaviruses and LBV were detected in all continental populations. Isolated island populations in the Gulf of Guinea were genetically distinct from each other and the continental population. Given the isolation of these island fruit bats and the lack of connectivity with other populations, it was expected that populations would be too small to allow persistence of any viruses that cause acute, immunising infections. Contrary to expectations, island individuals displayed evidence for exposure to both viruses. E. helvum is known to roost close in proximity to human populations across continental Africa, and these results could therefore have important public health implications. Further longitudinal studies across multiple locations and information on social structure, daily and seasonal movements are needed to make inferences about virus transmission dynamics and zoonotic risks within the complex population structure.

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Cerqueira, Silva Carlos Bernard Moreno 1983. "Diversidade genética molecular e reação a doenças de acessos silvestres e comerciais de maracujazeiro (Passiflora spp.) presentes em bancos de germoplasma = Molecular genetic diversity and disease reaction of commercial and wild access of passion fruit (Passiflora spp.) present in germplasm banks." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/316508.

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Orientadores: Anete Pereira de Souza, Ronan Xavier Corrêa
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-25T14:19:58Z (GMT). No. of bitstreams: 1 CerqueiraSilva_CarlosBernardMoreno_D.pdf: 123175108 bytes, checksum: 668158b424ffa91922546922a5837ce2 (MD5) Previous issue date: 2014
Resumo: O gênero Passiflora, cujas espécies são popularmente conhecidas como maracujazeiros, destaca-se na família Passifloraceae tanto pelo número de espécies (aproximadamente 520) quanto pela importância econômica associada à parte destas espécies. Os maracujazeiros ocorrem em diferentes países, sendo sua diversidade amplamente representada nas Américas, onde a Colômbia e o Brasil se destacam com aproximadamente 170 e 150 espécies de Passiflora, respectivamente. Economicamente os maracujazeiros despertam interesse pela beleza de suas flores, presença de princípios ativos medicinais, extração de óleos essenciais para indústria de cosméticos, produção de frutos para consumo in natura ou produção de derivados. O Brasil se destaca como maior produtor de maracujá, embora a produtividade nacional seja baixa (média de 14 T/ha-1 ano-1), quando comparada ao potencial da passicultura (± 50 T/ha -1 ano-1). Em parte essa baixa produtividade é ocasionada pela ausência de cultivares adaptadas às diferentes regiões produtoras e pela suscetibilidade das cultivares às principais enfermidades que acometem a cultura. Embora crescente, os programas de melhoramento genético do maracujazeiro apresentam resultados modestos frente às demandas existentes. Entre os obstáculos enfrentados pelos melhoristas, está a reduzida representatividade do gênero Passiflora em bancos de germoplasma, bem como a escassez de informações biológicas e agronômicas para maioria dos acessos. Assim, foi objetivo desta tese gerar informações genéticas e moleculares que contribuam para o melhoramento do maracujazeiro. Inicialmente foram construídas revisões críticas relacionadas aos avanços obtidos no melhoramento e na conservação das Passiflora com o uso de marcadores moleculares, bem como a cerca da principal doença que acomete a passicultura (virose do endurecimento dos frutos). Posteriormente foram obtidos, a partir de bibliotecas genômicas enriquecidas de microssatélites, 25, 17 e 52 novos pares de primers para P. cincinnata, P. edulis e P. setacea respectivamente, sendo observado um percentual de locos polimórficos inferior a 30% e um número médio de cinco alelos por loco. Testes de amplificação cruzada foram realizados para 14 espécies de maracujazeiros, sendo observada uma média de 70% de amplificação cruzada. De posse destes marcadores, foi estimada a distância e quantificada a estrutura genética entre 116 acessos (representados por 364 plantas distribuídas em três espécies). A partir dos dados de genotipagem e das análises estatísticas (descritivas, frequentistas e Bayesianas) foi observado baixa diversidade entre os acessos, e níveis moderado a alto de estruturação (com 0,08 ? Gst ? 0,38) e percentuais de alelos privados variando entre 20 e 40% entre os grupos sugeridos pelas estimativas Bayesianas (K=2 para P. cincinnata; K=3 ou 5, para P. edulis, e; K=2 ou 3 para P. setacea). Coleções nucleares representativas para até 100% da diversidade alélica amostrada foram sugeridas. Com base na caracterização de locos microssatélites e na avaliação de sintomas associadas à virose do endurecimento, verrugose e antracnose, observados em 36 acessos de P. edulis (amarelo e roxo), foi possível identificar grupos de acessos a serem priorizados em programas de (pré) melhoramento dedicados ao incremento de resistência em variedades cultivadas. Os resultados obtidos contribuem para o desenvolvimento dos programas de pré-melhoramento e melhoramento genético do maracujazeiro, além de auxiliarem no manejo e na conservação da variabilidade genética do gênero
Abstract: The genus Passiflora, whose species are popularly known as passion fruits, stands out in the family Passifloraceae both by the number of species (about 520) as well as the associated economic importance of some of these species. Passion fruits occur in different countries, with their diversity widely represented in the Americas, where Colombia and Brazil stand out with approximately 170 and 150 species of Passiflora, respectively. Economic interest in passion fruit emerged from the beauty of their flowers, presence of active medicinal principles, extraction of essential oils for cosmetics industry, fruits production for fresh consumption or derivatives production. Brazil is considered the largest producer of passion fruit, although national productivity is low (average 14 T/ha-1 year-1) when compared to passion fruit culture potential (± 50 T/ha -1 year-1). This low productivity is caused in part by the lack of adapted cultivars to the different production regions and due cultivars susceptibility to passion fruit major diseases. Despite an increasing rate, passion fruit breeding programs shows modest results versus existing demands. Among the obstacles faced by breeders, stand out the genus Passiflora reduced representation in germplasm banks, as well as the scarcity of biological and agronomic information for most accessions. Thus, the aim of this thesis was to generate information genetics and molecular that contributes to the passion fruit genetic breeding. Initially, critical reviews related to advances in Passiflora breeding and conservation using molecular markers, as along with information about the main disease affecting the passiculture (passion fruit woodiness disease) were presented. Novel primer pairs for P. cincinnata, P. edulis and P. setacea, in number of 25, 17 and 52 respectively, were subsequently obtained from microsatellite enriched genomic libraries, being observed a less than 30% polymorphic loci and an average number of five alleles per locus. Cross-amplification tests were performed for 14 species of passion fruit and an average of 70% cross-amplification was observed. Using these markers, genetic distance and structure were estimated among 116 accessions (represented by 364 plants distributed among three species). From genotyping and statistical analyzes data (descriptive, frequentist and Bayesian), low genetic diversity among accessions was observed. Also, Bayesian estimated suggested groups (K=2 for P. cincinnata, K=3 or 5 for P. edulis, and, K=2 or 3 for P. setacea) showed moderate to high levels of structuring (0.08 ? Gst ? 0.38) along with private alleles percentage ranging from 20 to 40%. Representative core collections ensuring up to 100% of the sampled allelic diversity were suggested. Based on microsatellite loci characterization and symptoms evaluation of associated woodiness virus, scab and anthracnose, observed in 36 accessions of P. edulis (yellow and purple), it was possible to identify groups of accessions to be prioritized in (pre) breeding programs dedicated to resistance improving in cultivars. These results contribute to the passion fruit pre-breeding and breeding programs development, and assist the genus genetic variability management and conservation
Doutorado
Genetica Vegetal e Melhoramento
Doutor em Genetica e Biologia Molecular

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36

Willman, Matthew. "Genetic Analysis of Black Raspberry Breeding Germplasm." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1563451332753356.

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37

Timm, Alicia Eva. "Morphological and molecular studies of tortricid moths of economic importance to the South African fruit industry." Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1347.

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38

Oliveira, Eder Jorge de. "Desenvolvimento e uso de marcadores microssatélites para construção e integração de mapas genéticos de maracujá-amarelo (Passiflora edulis Sims f. flavicarpa Deg.)." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/11/11137/tde-10012007-153537/.

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O maracujá-amarelo é uma espécie alógama, auto-incompatível, o que prejudica a geração de linhagens endogâmicas e, por conseqüência, a construção e integração de mapas de ligação pelas metodologias convencionais. A exemplo do que tem sido feito em outras espécies vegetais, populações F1 (com diferentes tipos de segregação) foram utilizadas para a construção dos mapas genéticos de maracujá. Mapas individuais para cada genitor do cruzamento foram gerados fazendo uso apenas de marcas com segregação 1:1. A integração desses mapas é possível com base em marcadores bi-parentais, quando ambos os genitores são heterozigóticos para os mesmos alelos que segregam na proporção 3:1 em F1. Apesar disso, o uso de marcadores codominantes e multialélicos, como os microssatélites, possuem maior valor, uma vez que permite a obtenção de estimativas de freqüência de recombinação e da fase de ligação com um menor viés. O objetivo deste estudo foi o desenvolvimento de marcadores microssatélites utilizando bibliotecas genômicas enriquecidas, visando à construção e a integração de mapas genéticos de maracujáamarelo. Foram usadas 160 plantas oriundas do cruzamento entre os acessos IAPAR-123 x IAPAR-06, marcadores AFLP com segregação 1:1 e 3:1 e marcadores microssatélites desenvolvidos no presente estudo. Para a construção dos mapas utilizou-se um algoritmo que estima, simultaneamente, a fase de ligação e a freqüência de recombinação. A biblioteca genômica enriquecida forneceu 107 clones contendo microssatélites, com uma eficiência de enriquecimento da ordem de 11%. Todas as seqüências contendo microssatélites foram analisadas e 26 locos mostraram-se polimórficos: 16 deles segregaram na proporção de 1:1; 1 na proporção de 3:1; 2 na proporção de 1:2:1 e 7 na proporção de 1:1:1:1. Com relação aos dados de AFLP, 253 locos mono-parentais (em 114 deles, o alelo dominante estava presente no genitor 06 e 139, no genitor 123) mostraram-se polimórficos com segregação 1:1. Outros 116 locos mostraram-se bi-parentais, segregando na proporção de 3:1. Foram obtidos 11 grupos de ligação (GL) sendo 8 grupos integrados e um GL com apenas dois marcadores. Também, um GL para cada genitor foi obtido, cuja integração não foi possível por falta de marcadores bi-parentais. Foi possível alocar no framework dos mapas genéticos, além dos microssatélites, as marcas de AFLP com segregação do tipo 3:1, que contribuíram para uma maior saturação e integração de oito dos nove grupos de ligação de maracujá-amarelo (2n = 18). Foram obtidos, em média, 25 marcadores por GL, que forneceram um comprimento de mapa de 1.765,6 cM. Este é o primeiro relato em Passiflora sobre o uso de marcadores microssatélites e do algoritmo proposto por Wu et al. (2002) visando à integração dos mapas anteriormente construídos com base na estratégia duplo pseudocruzamento teste. Este mapa integrado será útil na alocação de QTL (Quantitative Trai Loci) relacionados à resistência a doenças e a características de interesse agronômico, assim como para estudos genéticos e evolutivos.
The yellow passion fruit is an out-breeding, self-incompatible species, but those features impose severe constraints on the generation of inbred lines, consequently impairing the building and integration of linkage maps using conventional methodologies. Similar to the reports from other plant species, F1 populations (with distinct segregation modes) were used to build passion fruit genetic maps. Individual maps, one for each parent involved in the cross were generated solely employing genetic markers with 1:1 segregation. However, the integration of those maps is feasible using bi-parental markers, i.e. when both parents are heterozygous for the same alleles that show 3:1 segregation in F1. However, the use of co-dominant multi-allele markers, such as the microsatellites is even more important, since it allows recombination frequency and linkage phase estimates to be obtained less effected by bias. The goal of this research was the development of microsatellite markers using enriched genomic libraries for constructing and integrating genetic maps of yellow passion fruit. We have used 160 plants from a cross between the accessions IAPAR-123 x IAPAR-06, AFLP markers showing 1:1 and 3:1 segregations and microsatellite markers developed in the present work. The maps were built employing an algorithm that simultaneously estimates the linkage phase and the recombination frequency. The enriched library allowed us to obtain 107 microsatellite-containing clones, at an enrichment efficiency of 11%. All microsatellite-containing sequences were analyzed and 26 loci were shown to be polymorphic: 16 of them with a 1:1 segregation; 1 with a 3:1 segregation, 2 showing a 1:2:1 proportion and 7 with a 1:1:1:1 segregation pattern. In relation to the AFLP data, 253 mono-parental loci were shown to be polymorphic with a 1:1 segregation proportion (in 114 loci the dominant allele was present in the parent 06, and in 139 loci, the dominant allele was found in the parent 123). The remaining 116 loci were shown to be bi-parental, segregating in a 3:1 proportion. Eleven linkage groups (LG) were obtained, 8 of them being integrated and one LG with only two markers. Moreover, one LG for each parent was obtained, but due to the absence of bi-parental markers they were not integrated. It was possible to locate on the framework of the genetic maps, along with the microsatellites those AFLP markers showing a 3:1-segregation type, which contributed to a greater level of map saturation and to the integration of eight of the nine linkage groups of yellow passion fruit (2n=18). On average, we have obtained 25 markers per LG, providing a map distance of 1,765.6 cM. This is the first report in Passiflora on the use of microsatellite markers and the algorithm proposed by Wu et al. (2002) to integrate maps previously constructed using the double pseudo-testcross strategy. The integrated map will be useful for locating QTL (Quantitative Trai Loci) related to disease resistance and agriculturally interesting traits, as well as to provide tools for genetic and evolutionary studies.

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Jones, Gillian E. "Development of Tools to Assess the Effects of Lunasin on Normal Development and Tumor Progression in Drosophila Melanogaster." TopSCHOLAR®, 2013. http://digitalcommons.wku.edu/theses/1293.

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Soy contains many bioactive molecules known to elicit anti-cancer effects. One such peptide, Lunasin, has been shown to selectively act on newly transformed cells while having no cytotoxic effect on non-tumorigenic or established cancer cell lines. In this study we attempt to understand the developmental effects of Lunasin overexpression in vivo and create reagents that will help us understand Lunasin’s anti tumorigenic effects in an intact organism. cDNA encoding lunasin and EGFP-lunasin were cloned into pUAST and microinjected into Drosophila embryos. Tissue-specific overexpression of EGFP-Lun in the resulting transgenic lines was accomplished by crossing transgenics to various GAL4 driver lines. Progeny were assessed for phenotypic alterations and no phenotypic abnormalities were observed in tissues expressing EGFP-Lunasin, supporting current studies that show Lunasin does not affect normal cells. Previous studies have localized Lunasin to the nuclear compartment. To test if this was the case for EGFP-Lun, subcellular localization of EGFP-Lun was determined via fluorescence microscopy. Salivary glands from EGFP-Lun expressing individuals were dissected, fixed, and mounted in Vectashield® with the nuclear stain, DAPI. Our results demonstrate that EGFP-Lun, like native Lunasin, is localized to the nucleus. Eight transgenic lines were mapped to specific chromosomes and EGFP-Lun transgenic line GEJ1-L2 was balanced in preparation for use in tumor suppression studies. In summary, we have created and characterized transgenic flies capable of overexpressing Lunasin under the control of the GAL4/UAS system. Localization of EGFP-Lunasin to the nucleus and data on the phenotypic consequence of its overexpression in flies is presented. Finally, reagents created as part of this thesis will aid experiments aimed at understanding the effects of Lunasin on benign and invasive tumors.

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Porto, Alexandre Hack. "Intensidade luminosa no crescimento, produção e qualidade do fruto de jabuticabeira híbrida em condição de pomar." Universidade Tecnológica Federal do Paraná, 2018. http://repositorio.utfpr.edu.br/jspui/handle/1/3227.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
O Brasil está entre os maiores produtores mundiais de frutas, além de ser conhecido como um dos principais centros de diversidade genética de fruteiras silvestres. Na região Sul do país, a fruticultura de plantas nativas tem papel importante apesar de pouco explorada comercialmente, apresentando potencial, onde se destacam aquelas da família Myrtaceae, como a jabuticabeira. Porém, o uso da espécie para produção em pomar comercial é escasso, devido falta do conhecimento técnico para manejo, principalmente quando relacionado a intensidade de luz favorável para o crescimento e desenvolvimento da planta, lembrando que a mesma tem sua origem em mata. Dessa forma, prevalece o extrativismo e pequenos cultivos de plantas isoladas em fundos de quintal. Existem cerca de nove espécies de jabuticabeira, entre as mais conhecidas têm-se a Plinia peruviana (jabuticaba de cabinho), Plinia cauliflora (jabuticaba paulista ou jabuticaba Açu) e Plinia jaboticaba (Vell) (jabuticaba sabará). Contudo, têm-se uma no mercado denominada como híbrida que traz vantagens em relação as demais, como precocidade, número de colheitas por ano e baixo vigor, o que talvez seja indicativo para uso para obtenção de informações visando seu cultivo comercial. Com o trabalho, objetivou-se avaliar o comportamento do crescimento e desenvolvimento das plantas, bem como, a qualidade dos frutos de jabuticabeira híbrida cultivada em diferentes condições de intensidade luminosa. O trabalho foi desenvolvido no Pomar de Fruteiras Nativas, da Universidade Tecnológica Federal do Paraná – Câmpus Dois Vizinhos, implantado em 2013. O delineamento experimental foi blocos a acaso, com cinco tratamentos, quatro repetições, com duas plantas por unidade experimental. Os tratamentos foram constituídos pelo cultivo em Pleno sol, representando uma condição de pomar (PS); cobertura lateral e superior com tela de sombreamento, simulando condição de dossel mais aberto, com (35% de sombreamento) (S35); cobertura lateral e superior com tela de sombreamento, representando estádio em que o dossel da mata esteja se fechando, incidindo apenas irradiação solar indireta (50% de sombreamento) (S50); cobertura lateral com tela de sombreamento e superior sem cobertura, representando condição de clareira (70% sombreamento) (S70); cobertura lateral e superior com tela de sombreamento, simulando condição de dossel fechado com (80% de sombreamento) (S80). Foram avaliadas mensalmente e sazonalmente variáveis de crescimento e desenvolvimento das plantas. As variáveis físicas e bioquímicas dos frutos, casca, polpa e folhas e a atividade microbiana. O crescimento de jabuticabeiras híbridas em condição de pomar foi favorecido com o uso de malhas de sombreamento, exceto quando se aplicou a malha de 80% de sombreamento. As características físicas e químicas dos frutos e a atividade microbiana do solo não tiveram diferenças estatísticas entre os tratamentos testados.
Brazil is among the largest producers of fruits, besides being known as one of the main centers of genetic diversity of wild fruit. In the South of the country, the fruit of native plants plays an important role despite little commercially exploited, with potential, where we highlight those of the Myrtaceae family, as jabuticabeira. However, the use of the species for production in orchard is scarce, due to the lack of technical knowledge to orchard management, especially when related to intensity of light favorable to the growth and development of the plant, remembering that it has its origin in the woods. Thus, the prevailing extraction and small plant crops in isolated backyards. There are about nine species of jabuticabeira, among the best known have to Plinia peruviana (jabuticaba cabinho), Plinia cauliflora (jabuticaba Paulista ou jabuticaba Açu) and Plinia jabuticaba (Vell) (jabuticaba sabará). However, there have been a marketing named as hybrid that brings advantages over the others, as precocity, number of harvests per year and low vigor, which may be indicative for use to obtain information aimed at its commercial cultivation. The study aims to evaluate the growth behavior and development of plants, as well as the quality of the fruits of hybrid jabuticabeira grown under different conditions of light intensity. The work will be developed in Orchard Fruit trees native of the Federal Technological University of Paraná - Campus Dois Vizinhos, established in 2013. The experimental design will block the chance, with five treatments, four replications, with two plants each. The treatments were constituted by cultivation in Pleno sol, representing an orchard condition (PS); lateral and upper cover with shade screen, simulating a more open canopy condition, with (35% shading) (S35); lateral and upper cover with shade screen, representing a stage in which the forest canopy is closing, with only indirect solar irradiation (50% shading) (S50); lateral cover with shade and top without cover, representing clearing condition (70% shading) (S70); lateral and upper cover with shade screen, simulating closed canopy condition with (80% shading) (S80). The physical and biochemical variables of fruits, bark, pulp and leaves and the microbial activity. The growth of hybrid jabuticaba trees in orchard condition was favored by the use of shading meshes, except when the 80% shading mesh was applied. The physical and chemical characteristics of the fruits and the microbial activity of the soil did not have statistical difference between the tested treatments.

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Lopes, Gleidyane Novais. "Análise morfométrica e molecular de morfotipos do complexo fraterculus (Diptera, Tephritidae, Anastrepha) de duas populações do Paraguai." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/11/11146/tde-10022011-090318/.

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A alta diversidade observada em Anastrepha fraterculus em toda sua área de distribuição caracteriza a existência do complexo fraterculus. A correta identificação de espécies de Anastrepha aparentadas atualmente exige a utilização de uma série de técnicas. Assim, o presente trabalho propõe verificar quão semelhantes os morfotipos de duas populações do complexo A. fraterculus são, usando dados morfológicos (morfometria tradicional e geométrica) e moleculares (marcadores nucleares e mitocondriais). As amostras de dois municípios do Paraguai (Concepción e Santa Rosa) foram analisadas e seis morfotipos (chamados de M1 a M6) foram reconhecidos (M1-M5 em Concepción; M1-M4 e M6 em Santa Rosa), com base nas variações do ápice do acúleo, e um morfotipo com o acúleo típico do complexo fraterculus. A análise multivariada das oito medidas tomadas a partir do acúleo indicaram diferenças entre todos os morfotipos. A análise morfométrica baseada na morfometria convencional também revelou a existência de variabilidade entre os morfotipos estudados, mas alguns espécimes do morfotipo M4 foram similares aos espécimes de morfotipos M5 e M3, em Concepción. As asas também foram submetidas à morfometria geométrica usando 20 marcos, que indicou a existência de variabilidade entre e dentro dos morfotipos. Morfotipos da população de Concepción tendem a formar grupos distintos. No entanto, além das variações morfológicas de morfotipos de ambas as populações analisadas, sequências parciais da citocromo oxidase I gene (Cox1) e região do espaçador interno transcrito 1 (ITS1) foram muito semelhantes entre si. Portanto, esses marcadores moleculares não diferenciaram os morfotipos estudados, os quais foram muito similares aos espécimes com o acúleo típico do complexo fraterculus.
The high diversity observed in Anastrepha fraterculus throughout its distribution range characterizes the existence of the fraterculus complex. The correct identification of closely related species of Anastrepha currently requires the use of a number of techniques. Thus, the present work is proposed to verify how similar morphotypes of two populations of the A. fraterculus complex are, by using morphological (conventional and geometric morphometry) and molecular (nuclear and mitochondrial markers) data. Specimens from two municipalities of Paraguay (Concepción and Santa Rosa) were analyzed and six morphotypes (named from M1 to M6) were recognized (M1-M5 in Concepción; M1-M4 and M6 in Santa Rosa) based on variations in the apex of the aculeus, and a morphotype with the typical aculeus of the fraterculus complex. Multivariate analysis of eight measurements taken from the aculeus indicated differences among all morphotypes. Morphometric analysis based on conventional morphometry also revealed the existence of variability among the morphotypes studied, but some specimens from morphotype M4 were similar to specimens from morphotypes M5 and M3 in Concepción. Wings were also subjected to geometric morphometry by using 20 landmarks, which indicated the existence of variability between and within morphotypes. Morphotypes from the population of Concepcion tended to form separate groups. However, besides the morphological variations observed for morphotypes from both populations analyzed, partial sequences of the citochrome oxidase I (Cox1) gene and the internal transcribed spacer 1 (ITS1) region were highly similar among them. Therefore, these molecular markers did not differentiate the morphotypes studied and were highly similar to specimens with the aculeus shape typical of the fraterculus complex.

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Virlet, Nicolas. "Phénotypage haut débit par imagerie multispectrale au verger : étude du déterminisme génétique de la réponse à la contrainte hydrique d'une population d'hybrides de pommier (Malus x domestica Borkh.)." Thesis, Montpellier, SupAgro, 2014. http://www.theses.fr/2014NSAM0021/document.

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Dans le contexte des changements climatiques prévisibles et d'une demande évaporative accrue vis à vis des cultures, ce travail de thèse vise à évaluer la variabilité génétique du pommier pour sa réponse à la contrainte hydrique. Cette évaluation est d'un intérêt certain pour l'amélioration future de l'espèce, qu'il s'agisse de mieux tolérer le stress pouvant résulter d'une sécheresse temporaire du sol, ou d'une efficience accrue d'utilisation de l'eau. Les méthodes de phénotypage actuellement disponibles pour l'étude de la réponse à la contrainte hydrique ne permettent pas un haut débit de mesure compatible avec les comparaisons simultanées entre de nombreux individus. En conséquence, ce travail de thèse s'est focalisé sur l'application de l'imagerie multi-spectrale aéroportée comme outil de phénotypage à haut débit en condition de plein champ et sur l'évaluation de sa pertinence pour l'analyse quantitative des réponses à la contrainte hydrique et la recherche des déterminismes génétiques associés. Les essais ont été réalisés sur une population hybride de pommiers (croisement Starkrimson x Granny Smith) âgée de 4 ans au début de l'étude, implantée dans le sud de la France. A partir d'images acquises dans les longueurs d'onde du visible, du proche infrarouge et de l'infrarouge thermique, à une résolution spatiale proche de 30cm, différents indices de végétation et de stress ont été calculés permettant d'apprécier la vigueur des arbres et leur transpiration. La prise en compte, dans des modèles linéaires mixtes, de six dates d'expérimentation, couvrant deux campagnes d'acquisitions, et de régimes d'irrigation différenciés sur la population a permis de mettre en évidence l'héritabilité des indices phénotypiques et conduit à la détection de nombreux QTLs. 18 QTLs se sont révélés indépendants de la date d'acquisition. Pour quatre de ces QTLs, dits adaptatifs, c'est-à-dire exprimés en conditions de stress, un certain nombre de gènes candidats potentiellement impliqués dans les réponses précoces responsables de la régulation stomatique ont été identifiés
In the context of foreseen climate changes and higher evaporative demand in crops, this PhD work is aiming at assessing the apple tree variability in response to hydric constraints. This could be of great interest for future breeding programs in this species, either in respect to temporary abiotic stress tolerance, or looking at a better water use efficiency. Phenotyping methods presently available for evaluating the plant response to hydric constraints do not allow the high-throughput that could be compatible with simultaneous comparison of a high number of individuals. As a consequence, this thesis focused on the application of airborne multispectral imagery as a tool for high-throughput field phenotyping, and it assessed the relevancy of this method for quantitative analysis of response to drought and further dissection of associated genetic determinisms. Trials were realized on a segregating hybrid apple population (Starkrimson x Granny Smith cross), 4-year old at the beginning of study, installed in the South of France. Images acquired in visible, near infrared and thermal infrared, with a spatial resolution close to 30cm, were the calculation basis of various vegetation and stress indices, allowing estimation of individual tree vigor and transpiration. Linear mixed models taking account of six flight dates, covering two acquisition campaigns and including two contrasted irrigation regimes over the apple population, made it possible to highlight the heritability of phenotypic indices and to perform numerous QTLs mapping. Eighteen QTLs were revealed independently from the acquisition date. Out of this QTLs set, a further analysis on 4 of them, which were adaptative i.e. expressed in stress conditions, allowed first identification of putative candidate genes potentially involved in the early stomatal closure

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Orchard, Caleb. "Naturally occurring variation in the promoter of the chromoplast-specific Cyc-B gene in tomato can be used to modulate levels of ß-carotene in ripe tomato fruit." The Ohio State University, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=osu1416926782.

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44

Uggla, Madeleine. "Domestication of wild roses for fruit production /." Alnarp : Dept. of Crop Science, Swedish Univ. of Agricultural Sciences, 2004. http://epsilon.slu.se/a480.pdf.

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45

Jeppsson, Niklas. "Genetic variation and fruit quality in sea buckthorn and black chokeberry /." Alnarp : Swedish Univ. of Agricultural Sciences (Sveriges lantbruksuniv.), 1999. http://epsilon.slu.se/avh/1999/91-576-5709-2.pdf.

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46

Wessendorf, Lisa H. V. "Genetic and molecular characterization of wing development in Drosophila." Thesis, University of Cambridge, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309358.

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47

Wang, Jiaojiao. "Study of starch metabolism in tomato fruit by using forward and reverse genetic approaches." Thesis, Bordeaux, 2020. http://www.theses.fr/2020BORD0213.

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L’amidon joue un rôle central pendant le développement et la maturation des fruits. Sa dégradation fournit de l’énergie et des sucres aux fruits en maturation tandis que son accumulation répond aux stress environnementaux. La connaissance du métabolisme de l’amidon dans les feuilles s’est considérablement améliorée, principalement grâce à la caractérisation des mutants d’Arabidopsis (sans amidon ou excédentaire), mais on en sait très peu sur les fruits. Dans cette étude, nous avons utilisé des approches de génétique directe et inverse pour obtenir des mutants de tomate produisant des fruits avec un excès d’amidon.Pour mener la démarche de génétique directe, nous avons combiné l’utilisation d’une plateforme robotisée permettant le dosage d’amidon à haut-débit avec celle d’une importante population de mutants EMS, et réalisé un criblage en utilisant des fruits rouges de près de 3000 individus. Trois candidats avec un excès d’amidon ont été trouvés, dont un (P17C12) a ensuite été confirmé avec une mutation récessive. Une grande population BC1F2 a été phénotypée puis utilisée pour localiser la mutation en utilisant une approche de cartographie par séquençage. Les résultats de l’analyse ont montré que la localisation la plus probable de la mutation est à l’extrémité du chromosome 1, avec 1 mutation KO, 2 mutations « faux-sens » et de nombreuses mutations dans des régions non codantes. Nous avons décidé de tester la RecQ hélicase 4 (RECQ4, Solyc01g103960, KO), un membre de la famille des protéines de transport mitochondrial (MCF, Solyc01g095510, « faux-sens »), un transporteur de phospholipides à ATPase (PTA, Solyc01g096930, « faux-sens »), un ORF situé en 5’ d’une protéine de fonction inconnue (CPuORF, Solyc01g105700, 5’ UTR) et la Rubrédoxine (Solyc01g097910, 3’UTR). Nous avons créé des mutants homozygotes KO ou faux-sens en utilisant CRISPR/Cas9 pour les gènes candidats RECQ4, MCF et PTA, et des mutants homozygotes avec mutations d’insertion / suppression dans le 5’ UTR pour CPuORF, mais aucun n’a montré de phénotype avec excès d’amidon. Pour la Rubrédoxine, en plus de créer des mutants KO et des mutants avec des mutations similaires dans 3’ UTR avec CRISPR/Cas9, nous avons également produit des plantes surexprimant la Rubrédoxine car chez mutant PP17C12, l’ARNm de la Rubrédoxine était fortement exprimé dans le fruit vert des lignées BC1F1 et S2. Le développement du mutant KO pour la Rubrédoxine (homozygotes) ne va pas au-delà du stade cotylédon. Les mutants avec des mutations dans 3’ UTR, qui n’ont montré aucun changement dans la quantité d’amidon ou les niveaux d'ARNm de Rubrédoxine. Certaines plantes ont montré des expressions 100 fois plus élevées de Rubrédoxine dans les feuilles, mais aucune n’a montré d’augmentation significative de la quantité d'amidon dans les fruits. Finalement, nous n’avons trouvé le phénotype avec excès d’amidon dans les fruits pour aucun des cinq gènes candidats testés, ce qui implique que davantage d'investigations seront nécessaires pour affiner la cartographie et identifier la mutation responsable de ce phénotype.En utilisant une approche de génétique inverse, nous avons sélectionné une alpha-amylase (AMY3.2) et trois bêta-amylases (BAM1.2, BAM3.2 et BAM9), pour lesquelles nous avons créé des mutants KO par CRISPR/Cas9. Nous avons obtenu des mutants KO homozygotes pour AMY3.2 et BAM9, et des mutants KO hétérozygotes pour BAM1.2 et BAM3.2 dans la génération T1. L'absence de BAM9 a conduit à une mauvaise fertilisation menant à une réduction du nombre de graines et à une diminution de la taille des fruits chez la plupart des mutants. Chez ces mutants, la quantité d'amidon était remarquablement élevée dans les fruits âgés de 35 DAP. Ces résultats préliminaires suggèrent que BAM9 pourrait jouer un rôle important dans la viabilité du pollen et dans la dégradation de l’amidon des fruits pendant le mûrissement
Starch plays a central role during fruit development and ripening. Its degradation provides energy and sugars in ripening fruits whereas its accumulation responds to environmental stresses, which suggests a buffering role. Knowledge of starch metabolism in leaves has dramatically improved, mostly through the characterization of Arabidopsis mutants (starch-less or -excessive), but only very little is known in fruits. In this study, we used both forward and reverse genetic approaches to obtain tomato mutants with starch-excess fruits.For applying forward genetics, we took advantages of the robotic platform and the large EMS mutant population of tomato (Micro-Tom, an ideal model for starch research), and performed a screen by using red fruits of nearly 3,000 individuals. Three starch-excess candidates were found and one (P17C12) could be confirmed as a homozygous mutant with a recessive starch-excess phenotype with Mendelian inheritance analysis. A large BC1F2 population was phenotyped and the starch-excess phenotype was mapped-by-sequencing. The sequence data obtained from the two bulks revealed that the mutation was likely located at the end of chromosome 1, a region that harbours 1 KO and 2 missense mutations as well as numerous mutations in non-coding regions. We decided to work with the KO, missense mutations and mutations in 5’ UTR and 3’ UTR first, which were a RecQ helicase 4 gene (RECQ4, Solyc01g103960), a mitochondrial carrier protein family gene (MCF, Solyc01g095510), a phospholipid-transporting ATPase gene (PTA, Solyc01g096930), a conserved peptide upstream open reading frame (CPuORF, Solyc01g105700), and a rubredoxin protein family gene (Solyc01g097910), respectively.To evaluate those mutations, we utilised different bioengineering techniques adapted to each case. We created KO or missense homozygous mutants by using CRISPR/Cas9 for RECQ4, MCF and PTA candidate genes, and homozygous mutants with insertion/deletion mutations in the 5’ UTR for CPuORF, but none of them showed a starch-excess phenotype. For Rubredoxin, besides creating KO mutants and mutants with similar mutations in 3’ UTR with CRISPR/Cas9, we also overexpressed Rubredoxin under the control of the 35S promoter as we found a significant increase of Rubredoxin mRNA in the 12 DAP (days after pollination) fruit of BC1F1 and S2 (P17C12), compared to the WT. The homozygous KO mutants could not grow through cotyledon stage, indicating that the lack of Rubredoxin is lethal for phototrophic plants. The mutants with mutations in 3’ UTR showed no changes in starch amount or mRNA levels of rubredoxin. Then, among the transformants overexpressing Rubredoxin, some showed 100 times higher expressions levels of Rubredoxin in leaves, but showed no significant starch increase in 20DAP fruit. Finally, none of the five candidate genes checked here led to a starch-excess phenotype in fruits, implying that more investigations are required regarding fine-mapping and mining the possible candidate genes.We also attempted to obtain starch-excess mutants via reverse genetics. We selected one alpha-amylase (AMY3.2) and three beta-amylases (BAM1.2, BAM3.2 and BAM9) to create the corresponding KO mutants by CRISPR/Cas9 techniques. We obtained homozygous KO mutants of AMY3.2 and BAM9, and heterozygous KO mutants of BAM1.2 and BAM3.2 in T1 generation. The mutants of two transgenic lines lacking AMY3.2 showed lower starch content in 20 DAP fruits. While the loss of BAM9 led to poor fertilization, and reduced seed numbers and fruit size in most mutants. Furthermore, in those mutants, starch levels were remarkably high in the ripening 35 DAP fruit. Then, in the red ripe fruit, mutants contained significant more glucose than WT fruits. Those results lead us to speculate that BAM9 may play important roles both in pollen viability and starch degradation during fruit ripening

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Cimò, Giuseppe. "Ploidy manipulation for genetic improvement in some Mediterranean fruit crops." Doctoral thesis, Universitat Politècnica de València, 2017. http://hdl.handle.net/10251/79874.

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Plant breeding is focused on selection of new genotypes with improved traits. Conventional methods based on hybridization and those based on biotechnology (somatic hybridization, genetic transformation, ploidy manipulation, etc.) are used to create novel genetic variations. Biotechnology provides powerful tools for plant breeding, for instance, haploid technology allows achievement of homozygous lines from heterozygous parents in one step, which reduces significantly the time required by conventional methods. Concerning woody species, characterized by self-incompatibility, long juvenile period and high degree of heterozygosity, this technique is the only way to get homozygous lines. Haploid plants are of great interest for breeding and genomic studies, being used in mutation research, genetic analysis, genome mapping and gene transfer. Gametic embryogenesis, based on cellular totipotency, produces an embryo from an immature gamete, by switching its developmental pathway from gametophytic to sporophytic. This research is focused on inducing gametic embryogenesis in two important Mediterranean fruit crops: almond (Prunus dulcis Mill.) via in vitro anther culture and mandarin (Citrus reticulata Blanco) via isolation and microspore culture. Also ploidy manipulation was applied to loquat (Eriobotrya japonica (Thunb.) Lindl.) for getting genotypes whit different ploidy levels. The experiments were carried out through years 2014, 2015 and 2016 at the 'Università degli Studi di Palermo' (UNIPA) as well as at the 'Instituto Valenciano de Investigaciones Agrarias' (IVIA). Regarding the almond anther culture, formation of calli and production of embryos was achieved through the direct embryogenesis route. On then other hand, early embryo regeneration is reported, for the first time, from isolated microspore culture of mandarin, 'Mandarino Tardivo di Ciaculli'. Our results report the evidence of gametic embryogenesis and the production of homozygous regenerants in almond and mandarin, two species extremely recalcitrant to microspore embryogenesis. However, the results are affected by many factors that need further studies to better understand the embryogenic development and to increase the rate of embryo achievement. Moreover, another biotechnological tool (ploidy manipulation) was also applied for implementing the IVIA loquat breeding program. Polyploid plants are of great interest in this species, due to its potential for producing seedless genotypes via direct use of triploids or crosses between tetra and diploids. Aimed at obtaining new loquat genotypes, with different ploidy levels (polyploids), colchicine was applied to seeds before germination, to induce chromosome duplication. A total of three triploids (3x) and one tetraploid (4x) were obtained.
La mejora genética tiene como objetivo la selección de nuevos genotipos con mejores características. Los métodos de mejora convencional basados en hibridaciones y aquellos basados en Biotecnología (hibridación somática, transformación genética, manipulación de la ploidía, etc.) se utilizan para obtener nueva variación genética. La Biotecnología proporciona herramientas poderosas en mejora genética, por ejemplo, la obtención de haploides permite obtener líneas homocigotas en un solo paso, disminuyendo significativamente el tiempo requerido usando métodos convencionales. Respecto a especies leñosas, caracterizadas por autoincompatibilidad floral, largo período juvenil y alto grado de heterocigosidad, esta técnica es el único método de obtención de líneas homocigotas. Los genotipos haploides tienen un alto interés en estudios genómicos, siendo utilizados en estudios de mutaciones, análisis genéticos, mapeo genético y transferencia genética. Este estudio tiene como objetivo la inducción de embriogénesis gamética en dos especies mediterráneas muy importantes: el almendro (Prunus dulcis Mill.) por medio de cultivo in vitro de anteras y el mandarino (Citrus reticulata Blanco) por medio de aislamiento de microesporas. Además, se ha estudiado la obtención de poliploides en níspero (Eriobotrya japonica (Thunb.) Lindl.) con el objetivo de obtener genotipos con diversos niveles de ploidía. Los experimentos se llevaron a cabo en los años 2014, 2015 y 2016 en la 'Università degli Studi di Palermo' (UNIPA) y en el 'Instituto Valenciano de Investigaciones Agrarias' (IVIA). Respecto al cultivo de anteras en almendro, la formación de callos y producción de embriones se obtuvo mediante embriogénesis directa. Por otro lado, se ha conseguido regenerar por primera vez embriones a partir de microesporas aisladas en el cultivar de mandarino 'Mandarino Tardivo di Ciaculli'. Los resultados obtenidos muestran que la embriogénesis gamética y la regeneración de embriones homocigótos en almendro y mandarino, dos especies extremadamente recalcitrantes para la embriogenésis a partir de microesporas, es posible. Sin embargo, los resultados se ven afectados por muchos factores que necesitan estudios adicionales para comprender mejor el desarrollo embriogénico y para aumentar la tasa de obtención del embriones. Además, otra herramienta biotecnológica (manipulación de la ploidía) se aplicó con el objetivo de implementar el programa de mejora de níspero del IVIA. Las plantas poliploides en esta especie tienen un alto interés, pues podrían permitir la obtención de frutos sin semilla, por medio de la obtención directa de triploides o mediante cruzamiento entre tetraploides y diploides. Con el objetivo de obtener nuevos genotipos de níspero con diferentes niveles de ploidía (poliploides), se aplicó colchicina a semillas sin germinar con el fin de inducir la duplicación cromosómica y se obtuvieron 3 triploides (3x) y un tetraploide (4x).
La millora genètica té com objectiu la selecció de nous genotips amb millors característiques. Els mètodes de millora convencional basats en hibridacions i aquells basats en Biotecnologia (hibridació somàtica, transformació genètica, manipulació de la ploïdia, etc.) s'utilitzen per aconseguir nova variació genètica. La Biotecnologia proporciona eines poderoses en millora genètica, per exemple, l'obtenció d'haploides permet obtenir línies homozigòtiques en un sol pas, disminuint significativament el temps requerit usant mètodes convencionals. Pel que fa a espècies llenyoses, caracteritzades per autoincompatibilitat floral, llarg període juvenil i alt grau d'heterozigosi, aquesta tècnica és l'únic mètode d'obtenció de línies homozigòtiques. Els genotips haploides tenen un alt interès en estudis genòmics, sent utilitzats en estudis de mutacions, anàlisis genètics, mapatge genètic i transferència genètica. Aquest estudi té com objectiu la inducció d'embriogènesi gamètica en dos espècies mediterrànies molt importants: l'ametller (Prunus dulcis Mill.) a través del cultiu in vitro d'anteres i el mandariner (Citrus reticulata Blanco) per mitjà d'aïllament de micròspores. A més a més, s'ha estudiat l'obtenció de poliploides en nespra (Eriobotrya japonica (Thunb.) Lindl.) Amb l'objectiu d'aconseguir genotips amb diversos nivells de ploïdia. Els experiments es van dur a terme en els anys 2014, 2015 i 2016 a la 'Università degli Studi di Palermo' (UNIPA) i a 'l'Institut Valencià d'Investigacions Agràries' (IVIA). Respecte al cultiu d'anteres en ametller, la formació de calls i producció d'embrions es va obtenir mitjançant embriogènesi directa. D'altra banda, s'ha aconseguit per primera vegada la regeneració d'embrions a partir de micròspores aïllades en el conrear de mandariner 'Mandarino Tardivo di Ciaculli'. Els resultats obtinguts mostren que l'embriogènesi gamètica i la regeneració d'embrions homozigotics en ametller i mandariner, dues espècies extremadament recalcitrants per l'embriogènesi a partir de micròspores, és possible. No obstant això, els resultats es veuen afectats per molts factors que necessiten estudis addicionals per entendre millor el desenvolupament embriogènic i per augmentar la taxa d'obtenció dels embrions. A més, una altra eina biotecnològica (manipulació de la ploïdia) es va aplicar amb l'objectiu d'implementar el programa de millora de nespra de l'IVIA. Les plantes poliploides en aquesta espècie tenen un alt interès, ja que podrien permetre l'obtenció de fruits sense llavor, per mitjà de l'obtenció directa de triploides o mitjançant encreuament entre tetraploides i diploides. Amb l'objectiu d'aconseguir nous genotips de nespra amb diferents nivells de ploïdia (poliploides), es va aplicar colquicina a llavors sense germinar per tal d'induir la duplicació cromosòmica i es van obtenir 3 triploides (3x) i un tetraploide (4x).
Cimò, G. (2017). Ploidy manipulation for genetic improvement in some Mediterranean fruit crops [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/79874
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49

Deljou, Ali. "Tissue culture and genetic transformation in potato breeding." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339661.

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Gonzaga, Lamartine Nogueira. "Caracterização morfoagronômica da coleção de germoplasma de jatobá-do-cerrado (Hymenaea stigonocarpa Mart. ex Hayne) da UFG." Universidade Federal de Goiás, 2017. http://repositorio.bc.ufg.br/tede/handle/tede/7197.

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Hymenaea stigonocarpa is classified as a priority for research and sustainable exploitation, with potential for fruit production. There is a phenotypic variation in the species that allows the distinction of three botanical varieties based on leaf characters. The present study aimed to characterize and evaluate the magnitude and distribution of the genetic variability of a germplasm collection of the species. The experimental material consisted of 336 accessions of 120 maternal families, from 24 subpopulations sampled in the Brazilian Cerrado. Plant height, stem diameter, number of branches and number of leaves were measured. Later, they were measured the morpho-agronomic variables: leaf length, leaf width, petiole length, petile diameter, leaf angle, leaflets angle and chlorophyll index. Growth dynamics and analysis of variance were performed to estimate genetic and statistical parameters and selection gain, for growth traits. Data from 113 progenies were used to estimate phenotypic and genetic correlation coefficients. It was also determined the relative importance of the variables for genetic divergence. The dynamics of growth were different in different periods, which is attributed to the formation of the root system in the initial phase of growth. The effects of progeny and subpopulation explain considerably part of the total variation, being significant between and, predominantly, not significant within subpopulations for the growth variables. The morpho-agronomic traits showed significant variation within subpopulations. The cluster analysis showed the formation of two distinct groups which corroborates a population study previously carried out with molecular markers. There is significant variation between subpopulations for growth trais, with possibility of selection for these variables. Based on morphological agronomic variables, the genetic variability is structured among subpopulations. Plants with high growth rates in height have a high growth rate of stem diameter. The variables petiole length (CP), petiole diameter (DP) and final stem diameter (DF) were the most determinant in the discrimination of accessions.
O jatobá-do-cerrado é uma espécie nativa do Cerrado, classificada como prioritária para a pesquisa e exploração sustentada em médio prazo, para produção de frutos. Há variação fenotípica na espécie que permite a distinção de três variedades por caracteres das folhas. O presente estudo teve como objetivo caracterizar e avaliar a magnitude e distribuição da variabilidade genética de uma coleção de germoplasma da espécie. O material experimental foi constituído por 336 acessos de 120 progênies maternas, de 24 subpopulações amostradas no Cerrado. Foram realizadas leituras das variáveis de crescimento: altura da planta, diâmetro do caule, número de ramificações e número de folhas. Posteriormente foram mensuradas as variáveis morfoagronômicas: comprimento do entrenó, comprimento do folíolo, largura do folíolo, comprimento do pecíolo, diâmetro do pecíolo, ângulo da folha, ângulo dos folíolos e índice de clorofila. Foi avaliada a dinâmica do crescimento e estimados componentes de variância para obtenção de parâmetros genéticos, estatísticos e ganho de seleção para os caracteres do crescimento. Dados de 113 progênies foram utilizados na estimativa de coeficientes de correlação. Foi determinada, ainda, a importância relativa das variáveis para a divergência genética. A dinâmica do crescimento foi diferente em períodos distintos, o que é atribuído à formação do sistema radicular na fase inicial de crescimento. Os efeitos de progênie e subpopulação explicam consideravelmente parte da variação total captada, sendo significativa entre e, predominantemente, não significativa dentro de subpopulações para as variáveis do crescimento. Com os caracteres morfoagronômicos houve significativa variação dentro de subpopulações. A análise de divergência por agrupamento mostrou a formação de dois grupos distintos o que corrobora estudo populacional realizado anteriormente com marcadores moleculares. Existe variação significativa entre subpopulações para os caracteres de crescimento, com possibilidade de seleção para estas variáveis. Há, com base em variáveis morfoagronômicas, estruturação da variabilidade genética entre subpopulações. Plantas com elevadas taxas de crescimento em altura apresentam elevada taxa de crescimento do diâmetro do caule. As variáveis avaliadas comprimento do pecíolo (CP), diâmetro do pecíolo (DP) e diâmetro final do caule (DF) foram as mais determinantes na discriminação dos acessos.

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