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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Application of Conventional, Biotechnological and Genomics Approaches for Eggplant (Solanum melongena.L). Breeding with a Focus on Bioactive Phenolics

Kaushik, Prashant 03 November 2019 (has links)
[ES] En el primer capítulo, se caracterizó una colección de seis accesiones de berenjenas, 21 accesiones de 12 especies silvestres y 45 híbridos interespecíficos de berenjena con especies silvestres utilizando 27 descriptores morfológicos y 20 descriptores morfométricos de frutos basados en la herramienta fenómica Tomato Analyzer. Observamos diferencias significativas entre los tres grupos, con híbridos que muestran valores intermedios para la mayoría de los descriptores. Las especies silvestres mostraron una amplia diversidad para ampliar la base genética de la berenjena. En el segundo capítulo, el mismo material se caracterizó para el contenido en compuestos fenólicos del fruto, el color de la pulpa de la fruta y los caracteres relacionados con el pardeamiento. Mientras que el ácido fenólico predominante en la berenjena cultivada fue el ácido clorogénico (> 65.0%), en los parientes silvestres fue de menos del 50% del área del pico del cromatograma HPLC. Las variedades cultivadas presentaron un color de carne más claro y baja actividad de polifenol oxidasa (PPO). Los híbridos interespecíficos fueron intermedios para todos los caracteres estudiados. En el tercer capítulo, realizamos un estudio genético Linea por Probador (L × P) utilizando dos líneas cultivadas, una con citoplasma oriental y otra occidental con cuatro probadores que representan tres especies silvestres: S. insanum, S.anguivi y S . lichtensteinii. Además, evaluamos el material para 3 descriptores bioquímicos, 12 morfológicos y 8 de Tomato Analyzer. Encontramos diferencias significativas para los 23 caracteres estudiados. Los valores más altos para la componente SCA se determinaron en comparación con la componente GCA. En general, los probadores del genepool secundarios fueron mejores para la mejora de los caracteres bioquímicos, mientras que las especies de genepool primarias fueron mejores para los caracteres morfológicos. En el cuarto capítulo, para obtener información sobre la genética de caracteres importantes en la berenjena, realizamos el primer estudio genético detallado de la berenjena con 10 genotipos diversos de berenjena, entre ellos una accesión de S. insanum, mientras que el resto fueron variedades tradicionales con forma del fruto muy diversa. Cuando se cruzaron en un diseño de medio dialelo, los 10 padres produjeron un conjunto de 45 híbridos. Evaluamos padres e híbridos para 14 descriptores de características morfológicas y 14 características morfométricas del fruto. También determinamos las distancias genéticas utilizando 7,335 marcadores de SNP polimórficos. Del mismo modo, en el quinto capítulo, estudiamos los compuestos fenólicos del fruto, el color de la pulpa del mismo y los caracteres relacionados con el pardeamiento en el mismo material. Se determinó que la accesión de S. insanum accession INS2 presenta valores altamente significativos para los compuestos fenólicos totales y el contenido de ácido clorogénico. Se encontraron efectos significativos para la aptitud combinatoria específica y general para los caracteres bioquímicos estudiados. De manera similar a lo encontrado anteriormente, la distancia genética entre los padres no fue útil para predecir el comportamiento de los híbridos.Finalmente, en el sexto capítulo, hemos desarrollado un protocolo de agroinfiltración para la expresión transitoria de un gen en el fruto de la berenjena utilizando GUS; Vector pCAMBIA1304. Posteriormente, para probar la utilidad del protocolo, utilizamos la hidroxicinamoil CoA-quinato transferasa (SmHQT) de berenjena, que es la enzima central estudiada para aumentar el contenido de ácido clorogénico, en la construcción del gen con el promotor específico en un vector de transformación de plantas (pBIN19). Además, en nuestro casete, también coexpresamos la proteína P19 del Tomato bushy stunt virus para sobreexpresar la proteína. En esta tesis proporcionamos información sobre los parientes sil / [CAT] En el primer capítol, es va caracteritzar una col·lecció de sis accessions d'albergínies, 21 accessions de 12 espècies silvestres i 45 híbrids interespecífics d'albergínia amb espècies silvestres utilitzant 27 descriptors morfològics i 20 descriptors morfomètrics de fruits basats en l'eina fenómica Tomato Analyzer. Observarem diferències significatives entre els tres grups, amb híbrids que mostren valors intermedis per a la majoria dels descriptors. Les espècies silvestres van mostrar una àmplia diversitat per a ampliar la base genètica de l'albergínia.En el segon capítol, el mateix material es va caracteritzar per al contingut en compostos fenòlics del fruit, el color de la polpa de la fruita i els caràcters relacionats amb el pardejament. Mentre que l'àcid fenòlic predominant en l'albergínia cultivada va ser l'àcid clorogènic (> 65.0%), en els parents silvestres va ser de menys del 50% de l'àrea del pic del cromatograma HPLC. Les varietats cultivades van presentar un color de carn més clar i baixa activitat de polifenol oxidasa (PPO). Els híbrids interespecífics van ser intermedis per a tots els caràcters estudiats. Curiosament, no trobem correlacions significatives entre el contingut de compostos fenòlics totals o àcid clorogènic i el pardejament de la polpa de la fruita. En el tercer capítol, realitzem un estudi genètic Línia per Emprovador (L × P) utilitzant dues línies cultivades, una amb citoplasma oriental i una altra occidental amb quatre emprovadors que representen tres espècies silvestres: S. insanum, S. anguivi i S. lichtensteinii. A més, avaluem el material per a 3 descriptors bioquímics, 12 morfològics i 8 de Tomato Analyzer. Trobem diferències significatives per als 23 caràcters estudiats. Els valors més alts per a la component SCA es van determinar en comparació amb la component GCA. En el quart capítol, per a obtindre informació sobre la genètica de caràcters importants en l'albergínia, realitzem el primer estudi genètic detallat de l'albergínia amb 10 genotips diversos d'albergínia, entre ells una accessió de S. insanum, mentre que la resta van ser varietats tradicionals amb forma del fruit molt diversa. Quan es van creuar en un disseny de mitjà dial·lel, els 10 pares van produir un conjunt de 45 híbrids. Avaluem pares i híbrids per a 14 descriptors de característiques morfològiques i 14 característiques morfomètriques del fruit. També determinem les distàncies genètiques utilitzant 7,335 marcadors de SNP polimòrfics. En l'estudi de l'herència dels caràcters morfològics importants per al desenvolupament d'híbrids en albergínia, es va trobar que la distància genètica entre els pares té un valor limitat per a predir el rendiment dels híbrids en aquest cultiu. Es va determinar que l'accessió de S. insanum accessió INS2 presenta valors altament significatius per als compostos fenòlics totals i el contingut d'àcid clorogènic. Es van trobar efectes significatius per a l'aptitud combinatòria específica i general per als caràcters bioquímics estudiats. De manera similar a l'oposat anteriorment, la distància genètica entre els pares no va ser útil per a predir el comportament dels híbrids. Finalment, en el sisé capítol, hem desenvolupat un protocol d'agroinfiltració per a l'expressió transitòria d'un gen en el fruit de l'albergínia utilitzant GUS; Vector pCAMBIA1304. Posteriorment, per a provar la utilitat del protocol, utilitzem la hidroxicinamoil CoA-quinat transferasa (SmHQT) d'albergínia, que és l'enzim central estudiat per a augmentar el contingut d'àcid clorogènic, en la construcció del gen amb el promotor específic en un vector de transformació de plantes (pBIN19). A més, en el nostre casset, també coexpresem la proteïna P19 del Tomato bushy stunt virus per a sobreexpresar la proteïna. En aquesta tesi proporcionem informació sobre els parents silvestres d'albergínies per a caràcters morfològics i bioq / [EN] In the first chapter, a collection of six eggplant accessions, 21 accessions of 12 wild species (the only primary genepool species S. insanum and 11 secondary genepool species) and 45 interspecific hybrids of eggplant with wild species were characterized using 27 morphological descriptors and 20 fruit morphometric descriptors based on the phenomics tool Tomato Analyzer. We observed significant differences among the three groups with hybrids showing intermediate values for most of the descriptors. The wild species showed an extensive diversity for broadening the genetic base of eggplant. In the second chapter, the same material was characterized for the fruit phenolics, fruit flesh colour and browning related traits. Wild relatives showed greater variation for the fruit phenolics than cultivated eggplant. While, the predominant phenolic acid in cultivated eggplant was chlorogenic acid (>65.0%), in the wild relatives it was less 50% of HPLC chromatogram peak area. Cultivated varieties had lighter flesh colour and low polyphenol oxidase (PPO) activity. The interspecific hybrids were found to be intermediate for all the characters studied. Interestingly, we found no significant correlations between total phenolics or chlorogenic acid contents and fruit flesh browning. In the third chapter, we performed a Line by Tester (L ×T) genetic study using two cultivated lines one with oriental and another with occidental cytoplasm along with four testers representing three wild species namely, S. insanum, S.anguivi, and S. lichtensteinii. Further, we evaluated the material for 3 biochemical, 12 morphological and 8 Tomato Analyzer based descriptors. We found a significant amount of variation for all the 23 traits studied. The higher values for the SCA component were determined as compared to the GCA component. Overall, the secondary genepool testers were better for the biochemical traits improvement whereas, the primary genepool species was better for the morphological traits. In the fourth chapter, in order to gain information regarding the genetics of important traits in eggplant, we performed the first detailed genetic study of eggplant with 10 diverse eggplant genotypes among them an S. insanum accession, while the remaining nine were highly diverse shaped fruits of popular eggplant cultivars. When crossed in a half-diallel matting design 10 parents produced a set of 45 hybrids. We evaluated parents and hybrids for 14 morphological and 14 fruit morphometric traits descriptors. We also determined the genetic distances using 7,335 polymorphic SNP markers. In the study of the genetics of important morphological traits for hybrid development in eggplant, we found that genetic distance among parents had limited value to predict hybrid performance in this crop. Likewise, in the fifth chapter, we studied the fruit phenolics, fruit flesh colour and browning related traits in the same material. We determined that S. insanum accession INS2 displayed values highly significant for the total phenolics and CGA content. Significant specific and general combining ability effects were found for the biochemical traits studied. Similarly, the genetic distance among parents was nonsignificant to predict hybrids performance. Finally, in the sixth chapter, we have developed an agroinfiltration protocol for the transient expression of a gene in the eggplant fruit using GUS bearing; pCAMBIA1304 vector. Thereafter, to prove the usefulness of the protocol, we have used the eggplant hydroxycinnamoyl CoA-quinate transferase (SmHQT), which is the central enzyme studied to increase the chlorogenic acid content, in a gene construct with the specific promoter in a plant transformation vector (pBIN19). Also, in our cassette, we also co-expressed the P19 protein of Tomato bushy stunt virus to overexpress the protein. Overall, in this thesis, we have provided information regarding the wild relatives of eggplants from a morphological and biochemical prospective. / Kaushik, P. (2019). Application of Conventional, Biotechnological and Genomics Approaches for Eggplant (Solanum melongena.L). Breeding with a Focus on Bioactive Phenolics [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/122295 / TESIS
12

A study of the Phomopsis blight on eggplant emphasizing seed treatments as a possible means of practical economic control

Porter, Richard P. January 1942 (has links)
M.S.
13

An Ex-Ante Economic Impact Assessment of Bt Eggplant in Bangladesh, the Philippines and India

Mishra, Sanjiv 10 September 2003 (has links)
This study projects the economic impact of adoption of Bt eggplant in India, Bangladesh and Philippines. The welfare benefits from adoption of Bt eggplant are projected to be positive in all three countries. The welfare gains from adoption (discounted at 5 percent) are projected to be US $ 411 million for India, US $ 37 million for Bangladesh and US$ 28 million for the Philippines. Consumers gain about 57% of the welfare benefits, while the producers gain 43% of the total surplus. Simulation results indicate that India is in a position to make significant investments in the development and diffusion of the Bt eggplant technology, while the Philippines and Bangladesh are likely to benefit from the transfer and adoption of technology from India.The simulations assumed a low seed premium, which would help in increasing the rate of adoption of the technology by the farmers. The findings suggest that potential economic benefits from Bt eggplant are high and efforts should be continued to develop and integrate the Bt eggplant with other IPM practices for effective pest management. / Master of Science
14

Increase in Calorie Intake Due to Eggplant Grafting: Proof of Concept With the Use of Minimum Datasets

Mutuc, Maria Erlinda Manalo 22 December 2003 (has links)
Eggplant grafting implemented implemented in two field sites in the Philippines, in Nueva Ecija and Pangasinan are used as proofs of concept to illustrate and validate the feasibility of an impact assessment framework for determining the nutritional impact of technology-oriented agricultural activities. Nutritional impacts are assessed by disaggregating the market demand curve into demand curves by income groups using their separate price elasticities of demand. Considering only price effects, the increase in yields following a per unit cost reduction due to eggplant grafting has positive effects on the daily caloric intake per capita in the different income classes with the greatest impact on the lowest income class for both sites. Net increases in calorie intake ranges between 0.09 and 0.6 kilocalories per capita per day. / Master of Science
15

Identificação molecular de fitoplasma associado ao enfezamento do tomateiro (Lycopersicon esculentum) e da berinjela (Solanum melongena). / Molecular identification of phytoplasma associated to tomato (Lycopersicon esculentum) and eggplant (Solanum melongena) stunting.

Mello, Ana Paula de Oliveira Amaral 29 January 2004 (has links)
Fitoplasmas, procariotos sem parede celular e habitantes de floema, têm causado danos consideráveis em diversas culturas comercialmente importantes. A associação desses fitopatógenos com várias doenças que ocorrem em espécies hortícolas têm sido comumente registradas tanto no território brasileiro como em outras regiões do mundo. Em áreas de plantio comercial, na região de Piracicaba-SP e Bragança Paulista-SP, plantas de tomate e berinjela apresentando porte reduzido, clorose foliar acentuada, produção exagerada de pequenos ramos, desenvolvimento anormal do cálice, encurtamento de entre-nós, redução no tamanho de folhas, flores e frutos, que podem ser traduzidos em sintomas de enfezamento, foram observadas evidenciando infecção por fitoplasma. Através da técnica de duplo PCR utilizando os oligonucleotídeos universais R16 mF1/mR2 e R16 F2n/R2, fragmentos de DNA de 1,2 Kb foram amplificados de amostras sintomáticas, demonstrando a presença de fitoplasma nos tecidos das plantas. Nenhum fragmento foi detectado em plantas sadias. O exame de tecidos do floema de plantas sintomáticas, submetidos ao microscópio eletrônico de transmissão, revelou a presença de corpúsculos pleomórficos no interior dos vasos, corroborando com os resultados da detecção através de PCR. O uso de oligonucleotídeos específicos para identificação demonstrou a ocorrência de fitoplasmas afiliados ao grupo 16SrIII, tanto em tomate quanto em berinjela. Análises de RFLP, usando as enzimas de restrição AluI, MseI, HpaII, KpnI, RsaI, HhaI e MboI, confirmaram a ocorrência de fitoplasmas do referido grupo em ambas as espécies vegetais. Para confirmar os resultados de RFLP, os fragmentos de DNA de 1,2 Kb dos fitoplasmas presentes em tomate e berinjela, amplificados com o par de iniciadores R16 F2n/R2, foram clonados em Escherichia coli para a determinação de suas seqüências de nucleotídeos. Os fragmentos clonados sequenciados foram comparados, por homologia de nucleotídeos, entre si e com isolados cujas seqüências já haviam sido depositadas no "GenBank". O resultado do sequenciamento revelou heterogeneidade das seqüências do gene 16S rDNA ocorrendo em alguns isolados, demonstrando e confirmando a variabilidade genética de organismos do grupo 16SrIII presentes no Brasil. / Phytoplasmas are cell wall-less prokaryotes and phloem- inhabitants. They caused considerable damages in some commercially important crops in the Brazilian territory and others regions of the world. It has been observed in the region of Piracicaba and Bragança Paulista, São Paulo State, commercial fields of eggplant and tomate showing reduced size, extensive chlorosis, proliferation of axillary buds, abnormal development of calyx, internode shortening and small leaves, flowers and fruits. These symptoms can be translated by stunting, making clear the phytoplasma infection. Presence of phytophasm was confirmed by nested PCR assay with the universal primer R16 F2N/R2 where DNA fragments of 1.2 kb were amplified from symptomatic samples. No fragments was observed in healthy plants. Analysis of symptomatic plant’s phloem tissue when submitted to electron microscope of transmission, disclosed the presence of pleomorphic bodies inside the tissues, corroborating with the results of detection by PCR assay. The use of specific primers for groups demonstrated the phytoplasmas occurrence associated to the 16SrIII group, in both tomato and eggplant. RFLP analyses using AluI, MseI, HpaII, KpnI, RsaI, HhaI and MboI restriction enzymes confirmed the occurrence of phytoplasmas on 16SrIII group in both plant species with typical stunting symptoms. The products of 1.2 kb of tomato and eggplant isolates amplified with the pair of primers R16 F2n/R2, were cloned in Escherichia coli to determine nucleotides sequence and to confirm the RFLP results. The nucleotide sequences were compared by homology and with isolates whose sequence have been already deposited in the "GenBank". The results revealed 16S rRNA sequence heterogeneity occurring in some isolates showing the genetic variability of group 16SrIII phytoplasma in Brazil.
16

Identificação molecular de fitoplasma associado ao enfezamento do tomateiro (Lycopersicon esculentum) e da berinjela (Solanum melongena). / Molecular identification of phytoplasma associated to tomato (Lycopersicon esculentum) and eggplant (Solanum melongena) stunting.

Ana Paula de Oliveira Amaral Mello 29 January 2004 (has links)
Fitoplasmas, procariotos sem parede celular e habitantes de floema, têm causado danos consideráveis em diversas culturas comercialmente importantes. A associação desses fitopatógenos com várias doenças que ocorrem em espécies hortícolas têm sido comumente registradas tanto no território brasileiro como em outras regiões do mundo. Em áreas de plantio comercial, na região de Piracicaba-SP e Bragança Paulista-SP, plantas de tomate e berinjela apresentando porte reduzido, clorose foliar acentuada, produção exagerada de pequenos ramos, desenvolvimento anormal do cálice, encurtamento de entre-nós, redução no tamanho de folhas, flores e frutos, que podem ser traduzidos em sintomas de enfezamento, foram observadas evidenciando infecção por fitoplasma. Através da técnica de duplo PCR utilizando os oligonucleotídeos universais R16 mF1/mR2 e R16 F2n/R2, fragmentos de DNA de 1,2 Kb foram amplificados de amostras sintomáticas, demonstrando a presença de fitoplasma nos tecidos das plantas. Nenhum fragmento foi detectado em plantas sadias. O exame de tecidos do floema de plantas sintomáticas, submetidos ao microscópio eletrônico de transmissão, revelou a presença de corpúsculos pleomórficos no interior dos vasos, corroborando com os resultados da detecção através de PCR. O uso de oligonucleotídeos específicos para identificação demonstrou a ocorrência de fitoplasmas afiliados ao grupo 16SrIII, tanto em tomate quanto em berinjela. Análises de RFLP, usando as enzimas de restrição AluI, MseI, HpaII, KpnI, RsaI, HhaI e MboI, confirmaram a ocorrência de fitoplasmas do referido grupo em ambas as espécies vegetais. Para confirmar os resultados de RFLP, os fragmentos de DNA de 1,2 Kb dos fitoplasmas presentes em tomate e berinjela, amplificados com o par de iniciadores R16 F2n/R2, foram clonados em Escherichia coli para a determinação de suas seqüências de nucleotídeos. Os fragmentos clonados sequenciados foram comparados, por homologia de nucleotídeos, entre si e com isolados cujas seqüências já haviam sido depositadas no “GenBank”. O resultado do sequenciamento revelou heterogeneidade das seqüências do gene 16S rDNA ocorrendo em alguns isolados, demonstrando e confirmando a variabilidade genética de organismos do grupo 16SrIII presentes no Brasil. / Phytoplasmas are cell wall-less prokaryotes and phloem- inhabitants. They caused considerable damages in some commercially important crops in the Brazilian territory and others regions of the world. It has been observed in the region of Piracicaba and Bragança Paulista, São Paulo State, commercial fields of eggplant and tomate showing reduced size, extensive chlorosis, proliferation of axillary buds, abnormal development of calyx, internode shortening and small leaves, flowers and fruits. These symptoms can be translated by stunting, making clear the phytoplasma infection. Presence of phytophasm was confirmed by nested PCR assay with the universal primer R16 F2N/R2 where DNA fragments of 1.2 kb were amplified from symptomatic samples. No fragments was observed in healthy plants. Analysis of symptomatic plant’s phloem tissue when submitted to electron microscope of transmission, disclosed the presence of pleomorphic bodies inside the tissues, corroborating with the results of detection by PCR assay. The use of specific primers for groups demonstrated the phytoplasmas occurrence associated to the 16SrIII group, in both tomato and eggplant. RFLP analyses using AluI, MseI, HpaII, KpnI, RsaI, HhaI and MboI restriction enzymes confirmed the occurrence of phytoplasmas on 16SrIII group in both plant species with typical stunting symptoms. The products of 1.2 kb of tomato and eggplant isolates amplified with the pair of primers R16 F2n/R2, were cloned in Escherichia coli to determine nucleotides sequence and to confirm the RFLP results. The nucleotide sequences were compared by homology and with isolates whose sequence have been already deposited in the “GenBank”. The results revealed 16S rRNA sequence heterogeneity occurring in some isolates showing the genetic variability of group 16SrIII phytoplasma in Brazil.
17

EFFECT OF SOY PROTEIN-BASED EDIBLE COATINGS WITH ANTIOXIDANT ACTIVITY AND MODIFIED ATMOSPHERE PACKAGING ON THE QUALITY OF FRESH-CUT PRODUCES

Ghidelli, Christian 29 July 2014 (has links)
Durante los últimos años la creciente demanda por parte del consumidor de alimentos frescos, de primera calidad y listos para preparar y servir, ha generado un cambio importante en la aplicación de técnicas de conservación de alimentos, abriéndose nuevas líneas en el mercado. Ante este reto, la industria ha respondido mediante la elaboración de productos minimamente procesados en fresco. Sin embargo, estos alimentos presentan una vida útil corta, principalmente debido a problemas de pardeamiento. La metodología para controlar este tipo de problema se basa en la utilización de antioxidantes y atmósferas modificadas con bajo nivel de O2. Sin embargo, la sola aplicación de estas tecnologías, en muchos casos, resulta poco efectiva para garantizar una vida útil adecuada del producto minimamente procesado. Por lo tanto, resulta necesario seguir estudiando en el desarrollo y aplicación de otras tecnologías que ayuden a mantener la calidad de estos productos durante periodos adecuados para su comercialización. En este proyecto, se pretende estudiar la efectividad de tratamientos antioxidantes con recubrimientos comestibles y el envasado en atmósferas modificadas `no convencionales¿, con el objetivo de reducir el pardeamiento enzimático en productos como alcachofa, berenjena, manzana y caqui minimamente procesados. / Ghidelli, C. (2014). EFFECT OF SOY PROTEIN-BASED EDIBLE COATINGS WITH ANTIOXIDANT ACTIVITY AND MODIFIED ATMOSPHERE PACKAGING ON THE QUALITY OF FRESH-CUT PRODUCES [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/39104 / TESIS
18

Dissection of Innate Immunity in Tomato and Tolerance to Bacterial Wilt in Solanaceae species

Naumenko, Anastasia Nikolayevna 05 April 2013 (has links)
Unlike mammals, plants do not have specific immune cells. However, plants can still recognize pathogens and defend themselves. They do that by recognizing microbial-associated molecular patterns (MAMPs) and secreted pathogen proteins, called effectors. MAMP-triggered immunity (MTI) relies on recognition of MAMPs by leucine-rich repeats (LRRs) pattern-recognition receptors (PRRs). The best-studied LRR PRR is Flagellin-Sensitive 2 (Fls2), the receptor of a 22-amino acid long epitope of bacterial flagellin, called flg22. In this project, alleles of FLS2 of different tomato cultivars were sequenced and compared to each other to get insight into natural selection acting on FLS2 and to identify residues important for ligand binding. This information may be used in the future to engineer Fls2 for improved ability to recognize flagellin. MTI can be suppressed by effectors secreted by bacteria into plant cells through the type III secretion system. On the other hand, plants are equipped with repertoires of resistance proteins, which can recognize some pathogen effectors. If a pathogen carries an effector that is recognized, effector-triggered immunity (ETI) is activated and the plant is resistant. Here, eggplant breeding lines were screened for their ability to activate ETI upon recognition of effectors of the soil borne pathogen Ralstonia solanacearum, a causative agent of bacterial wilt. Four effectors were found to trigger plant defenses in some of the lines. This is the first step in cloning the genes coding for the responsible resistance proteins. These genes may be used in the future for engineering tomato and potato for resistance to bacterial wilt. / Master of Science in Life Sciences
19

Etude du rôle lors de l'infection et sur la défense des plantes hôtes des effecteurs de type III RipH1,2,3 et RipAX2 de Ralstonia pseudosolanacearum / Role during infection and on plant defense of the type III effectors RipH1,2,3 and RipAX2 from Ralstonia Pseudosolanacearum

Morel, Arry 17 December 2018 (has links)
Le système de sécrétion de type III est un des déterminants majeurs de la pathogénicité de Ralstonia pseudosolanacearum qui lui permet d’injecter des effecteurs de type III (les « Rip », « Ralstonia Injected Protein ») directement dans les cellules des plantes hôtes. Les effecteurs RipH1, RipH2 et RipH3 sont des effecteurs de type III conservés dans la plupart des souches séquencées. Au cours de ma thèse, le rôle de ces effecteurs RipH lors de l’infection de différentes plantes a été étudié en prenant comme point d’entrée les protéines de tomates avec lesquelles ces effecteurs interagissent. Un criblage par double hybride dans la levure a permis d’identifier 19 de ces protéines « cibles » de tomate. Des méthodes de génétique inverse ont ensuite été utilisées pour chercher le rôle des orthologues de ces protéines dans différentes plantes modèles lors de l’infection par Ralstonia pseudosolanacearum. Du VIGS chez Nicotiana benthamiana a permis de mettre en évidence l’implication des orthologues de la protéine TOM3 : la multiplication bactérienne est moins importante dans les feuilles lorsque l’expression de ces gènes est diminuée. Dans Arabidopsis thaliana, des mutants d’un gène orthologue de la cible TOM9, décrit comme jouant entre autres un rôle dans la remodélisation de la chromatine, est plus résistant à l’infection par R. pseudosolanacearum. Dans un deuxième chapitre correspondant à un article publié, le rôle de l’effecteur RipAX2 a été étudié dans la résistance des aubergines AG91-25. La présence de cet effecteur dans la souche GMI1000 est nécessaire à l’établissement de la résistance de cette variété dans laquelle le locus de résistance EBWR9 a été mis en évidence. L’ajout de RipAX2 dans la souche PSS4, une souche pathogène de AG91-25 qui ne possède pas cet effecteur naturellement, la rend non pathogène. De plus, le motif protéique putatif « zincbinding » qui est décrit comme nécessaire pour l’induction de réponses de défense chez l’espèce proche de l’aubergine Solanum torvum n’est pas nécessaire pour la résistance de AG91-25. Enfin, la conservation de l’effecteur RipAX2 dans les différentes souches du complexe d’espèces de Ralstonia solanacearum a été étudiée pour évaluer l’efficacité potentielle de cette source de résistance contre différentes souches. / One of the major virulence determinants of plant pathogenic Ralstonia species is the type III secretion system that enables it to inject proteins (also called “Ralstonia Injected Proteins” or Rip) into the host cells. The RipH1,2,3 type III effectors are conserved in different strains of the Ralstonia solanacearum species complex. The role of these effectors during infection has been studied, taking as an entry point the tomato proteins they interact with. Using yeast-two-hybrid screenings we have identified 19 tomato targets of these three RipH. Reverse genetics methods have then been used to study the role of orthologous genes of these targets in other model plants. Virus induced gene silencing in Nicotiana benthamiana showed that the orthologous genes of TOM3 were involved in plant response to Ralstonia pseudosolanacearum, as the bacterial multiplication was diminished in plants silenced for these genes. In Arabidopsis thaliana, mutants of the TOM9 orthologous gene which is described as involved in chromatin remodelisation were more tolerant to infection. In a second chapter corresponding to a published article, the role of RipAX2 has been studied. This effector triggers specific resistance in AG9125 eggplant which carry the major resistance locus EBWR9. This eggplant accession AG9125 is resistant to the wild type R. pseudosolanacearum strain GMI1000, while a ripAX2 defective mutant of this strain can cause wilt. The addition of ripAX2 from GMI1000 to the naturally pathogenic strain PSS4 suppresses its pathogenicity, demonstrating that RipAX2 causes AG9125 resistance. Moreover, a zinc binding motif described as necessary to induce defenses on the eggplant wild relative Solanum torvum upon RipAX2 recognition is not necessary for AG91-25 resistance. The conservation of RipAX2 has been studied in the different strains of the bacteria in order to determine the potential of this resistance source against various strains for breeding
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Obtenção de chips de berinjela (Solanun melongena L.) mediante processo combinado de desidratação osmótica em solução ternária e secagem convectiva

Fernandes, Maristela Alves 15 June 2012 (has links)
Made available in DSpace on 2015-04-17T14:49:22Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 1134733 bytes, checksum: 28cffd4f9ffcc33dac5566773d86f7c7 (MD5) Previous issue date: 2012-06-15 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work aimed to utilize the combined osmotic dehydration and convective drying process to obtain eggplant chips by a non-conventional healthier and more low cost way. The combined process was studied through a factorial experimental design having as independent variables the temperature (30-50°C), sucrose (27,5 to 42,5% w/w) and sodium chloride (3,75 to 6,25% w/w) solution concentrations and immersion time (142,5 to 247,5 min.). The dependent ones were the water loss (PA), sucrose gain (GSac), sodium gain (GSódio), and the GSac/GSódio ratio. Samples from each osmotic condition were dried at 60°C for 4 hours in a convective dryer with a 1m/s air velocity. The objective was to obtain a maximum water loss with a minimum sucrose and sodium impregnation. Statistic models were well fitted according to the Response Surface Methodology. Once PA was above 90% and water activity was less than 0,4 for all samples, it was used the GSac/GSódio ratio as a parameter for choosing the best process condition which should be maximum. Thus, from this analysis, the best way to obtain eggplant chips was at 50°C, with a sucrose and sodium chloride concentrations of 45% and 7,5%, respectively, for 127,5 minutes. This independent variables combination led to a final product with its sodium content sensory attenuated due the sucrose presence and based on this point of view, it could be considered a healthier product compared with similar commercial, as well as by non-use of conventional frying process. / O presente trabalho teve como objetivo a utilização da tecnologia combinada de desidratação osmótica e secagem para obtenção de berinjela seca em forma de chips , de modo a aproveitar esta matéria-prima e obter um produto final, por vias não convencionais, mais saudável e de baixo custo. O processo de desidratação osmótica seguida de secagem convectiva foi realizado através de um delineamento experimental, tendo como variáveis independentes a temperatura (30 50°C), concentração de sacarose (27,5 42,5% p/p) e concentração de cloreto de sódio (3,75 6,25% p/p) da solução osmótica e o tempo de imersão (142,5 247,5 min.), e como variáveis dependentes PA, GSac, GSódio, GSac/GSódio e aw, secas numa temperatura e tempo de 60°C e 4 horas, respectivamente, a uma velocidade de 1m/s, onde o objetivo foi obter uma máxima perda de água com uma mínima incorporação de sacarose e sódio. Foram ajustados modelos de primeira ordem segundo a metodologia de superfície de resposta. Uma vez que PA foi acima de 90% e a aw foi menor que 0,4 para todos os ensaios, utilizou-se como parâmetro de escolha da melhor condição do processo, a análise do agente osmótico, mediante a razão GSac/GSódio, a qual deveria ser máxima, segundo a composição de amostras de batata chips comerciais. A condição ideal para obtenção de berinjela seca em forma de chips foi T=50ºC, CSac=45%, CSal=7,5%, t=127,5 minutos, onde tal fato implica em um produto final com um teor de sódio sensorialmente atenuado devido à presença da sacarose e sendo considerado, portanto, mais saudável em função dos menores teores de sódio e sacarose, quando comparado com os similares comerciais, assim como também, pela não utilização do processo de fritura convencional.

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