[ES] El cultivo del caqui ha crecido enormemente en la región Valenciana en los últimos 20 años al presentarse como una alternativa interesante al cultivo de cítricos. Sin embargo, su cultivo se enfrenta a tres problemas importantes. En primer lugar, su producción es monovarietal y se centra en la variedad Rojo Brillante, lo que conlleva un riesgo sanitario y de mercado importante que pone de manifiesto la necesidad de aumentar el número de variedades disponibles. En segundo lugar, el cambio climático pone en peligro la producción de caqui en zonas mediterráneas debido a un aumento en la salinidad del agua y suelo. La salinidad afecta especialmente al caqui debido a sus efectos sobre la producción, calidad y postcosecha de la fruta. La falta de patrones tolerantes a la salinidad compatibles con las condiciones de cultivo además agrava este problema, por lo que es necesario el desarrollo de patrones clonales tolerantes a la salinidad. En tercer lugar, la industria del caqui está basada en la aplicación de tratamientos postcosecha de desastringencia. Aunque existen variedades naturalmente no astringentes, su uso en el Mediterráneo es complicado debido a la incompatibilidad con los patrones existentes. Además, la salinidad afecta gravemente la eficacia del tratamiento de desastringencia. Por ello, cabe destacar que se necesita más información acerca de los mecanismos moleculares que controlan el desarrollo de la astringencia para poder desarrollar nuevas variedades y/o unos tratamientos de desastringencia más efectivos. En el contexto de la mejora genética y la biología molecular, pueden distinguirse tres objetivos para mejorar las condiciones de cultivo en esta región: el desarrollo de nuevas variedades de caqui con una época de madurez distinta a Rojo Brillante, el desarrollo de patrones clonales tolerantes a la salinidad y compatibles con variedades no astringentes y la obtención de nuevos conocimientos acerca de las bases moleculares del mecanismo de regulación de la astringencia para optimizar los tratamientos postcosecha. La presente tesis ha contribuido a estos tres objetivos. Respecto a la obtención de nuevas variedades, se ha desarrollado un análisis de diversidad genética del banco de germoplasma del IVIA, lo que es un recurso importante para la planificación de cruces. Para asegurar una mejora genética eficiente y evitar redundancias en la colección, se ha efectuado un análisis de diversidad usando secuencias microsatélites. El análisis ha arrojado datos de gran utilidad, como el descubrimiento de alelos únicos, que permiten la identificación rápida de variedades, o la división de la colección de acuerdo con el tipo de astringencia del fruto, confirmando el fondo genético común de las accesiones que comparten este carácter. Además, el mapa de las relaciones filogenéticas generado será de gran utilidad para la planificación futura de cruces dentro del programa de mejora de caqui. Para abordar el problema de la salinidad, se han realizado distintos ensayos de estrés salino en invernadero con distintas poblaciones de especies utilizadas como patrón de caqui: Diospyros virginiana (tolerante a salinidad), Diospyros kaki (sensible a salinidad y compatible) y Diospyros lotus (sensible a salinidad). Además, debido a los caracteres de gran interés presentes en estas dos especies, se incluyó en los ensayos una población proveniente de un retrocruce entre D. kaki y D. virginiana. Como resultado, varios individuos de estas poblaciones se han seleccionado debido a su tolerancia a la salinidad, ya que podrían tener las características adecuadas para ser patrones clonales. Complementariamente, se han usado aproximaciones fisiológicas, transcriptómicas y de secuenciación masiva de transcriptoma para hacer una primera descripción de los mecanismos de tolerancia a la salinidad presentes en estas especies. Como resultado, se han descrito los principales caracteres relacionados con la tolerancia a la salinidad en el género Diospyros, como la compartimentalización de iones, la expresión en raíz de un gen similar a HKT-1, la abundancia de canales de cloruro o la arquitectura de raíz. Finalmente, para obtener más información sobre la biosíntesis de proantocianidinas, la molécula responsable de la astringencia, se formuló la hipótesis de la existencia de un complejo proteico del tipo MBW (MYB-bHLH-WD40) que podía regular la ruta molecular de forma análoga a la regulación existente en otras especies estudiadas. En primer lugar se secuenció un gen tipo WD40, posible ortólogo de TTG1 de Arabidopsis thaliana. El papel de este gen y otros genes del hipotético complejo (MYB2, MYB4 y MYC1) han sido estudiados mediante un análisis transcriptómico en distintos estadios de madurez de frutos astringentes y no astringentes. Además, se ha observado mediante microscopía la localización celular de estos genes mediante la expresión transitoria con fusión con fluorescencia en hojas de Nicotiana benthamiana y hemos analizado su interacción mediante ensayos de doble híbrido en levadura y BiFC (complementación bimolecular de fluorescencia) mediante expresión transitoria en hojas de Nicotiana benthamiana. Finalmente, hemos analizado los efectos de estos genes y de sus interacciones en la ruta de biosíntesis de proantocianidinas usando el promotor del gen ANR (antocianidin reductasa) y promotores de los genes reguladores MYC1 y MYB4, fusionándolos con una luciferasa como gen delator y coexpresándolos con distintas combinaciones de los genes del complejo MBW mediante expresión transitoria en hojas de Nicotiana benthamiana. Los resultados de estos ensayos confirman la interacción nuclear de estos genes y su papel en la regulación de la producción de la astringencia, dando lugar a un modelo básico con algunas diferencias a los propuestos en otras especies. / [EN] Persimmon culture has vastly grown in the last 20 years as an alternative to citrus production in the Valencian region. However, its production faces three important problems. First, monovarietal production based on Rojo Brillante is a sanitary and market risk that requires to increase the number of varieties available. Second, climate change has threatened persimmon production in the Mediterranean areas because the salinity increase in water and soil. Salinity severely affects production, quality and postharvest life of the fruit. The lack of salt-tolerant rootstocks compatible with the cultural conditions aggravates the problem; hence clonal salt-tolerant rootstocks are needed. Third, persimmon industry relies on the postharvest deastringency treatment of the varieties. Even though there are varieties that are naturally non-astringent, its culture in the Mediterranean area is limited due to rootstock incompatibility. Additionally, the costly postharvest treatment is also affected by salinity. Consequently, more information is needed about the molecular mechanism of astringency biosynthesis in persimmon fruit in order to develop new varieties and/or more effective treatments for removing astringency of the fruit. In the context of breeding and molecular biology, three goals need to be approached in order to improve the cultural conditions: development of new persimmon varieties with maturity date different from Rojo Brillante, development of salt-tolerant clonal rootstocks compatible with non-astringent varieties and research on the molecular bases of the mechanism of astringency production to optimize the postharvest treatments. This research contributes and provides knowledge to address these goals. Concerning breeding of new varieties, the IVIA persimmon germplasm collection is an important resource for breeding of new varieties. To ensure efficient breeding and avoid redundancy in the collection, a SSR analysis was carried out to solve this problem. This analysis has provided useful data, such as the discovery of unique alleles, that allows rapid identification of varieties or the division of the population according to its astringency type, confirming the common genetic background of the accessions concerning to this trait. The generated genetic diversity map will be useful for designing crosses in the breeding program. To address the salinity problem, several salt-stress assays were done in greenhouse using different persimmon rootstocks populations: Diospyros virginiana (salt-tolerant), Diospyros kaki (salt-sensitive fully compatible) and Diospyros lotus (salt-sensitive). Furthermore, due to the desirable characters present in these species, a backcross progeny between D. kaki and D. virginiana was obtained and included in the salt-stress assays. Thus, several individuals from all the populations have been selected, which are tolerant to salinity and could meet the desired characteristics for appropriate persimmon clonal rootstocks. Furthermore we have used physiological, transcriptomic and mass transcriptome sequencing approaches in order to discover the physiological and genetic bases of salinity tolerance in these species. As a result, we described the main facts related to salinity tolerance mechanisms in Diospyros species, such as ion compartmentalization, HKT-1-like root expression, abundancy of chloride channels and root architecture. Finally, in order to get a deeper insight on the biosynthesis of proanthocyanidins, the responsible molecule of astringency, we hypothesized the presence of a MBW protein complex (MYB-bHLHWD40) in persimmon fruit, involved in the regulation of the proanthocyanidins synthesis pathway in a similar way to other species. We firstly sequenced the putative persimmon WD40 orthologue of TTG1 gene from Arabidopsis thaliana. The role of this gene and other genes of the complex (MYB2, MYB4 and MYC1) was studied through transcriptomic analysis in different stages of nonastringent and astringent fruit. Furthermore, we have observed through microscopy the subcellular localization of these genes using fluorescent protein fusions and transient expression in Nicotiana benthamiana leaves, and analyzed its interaction through yeast twohybrid assays and BiFC (bimolecular fluorescence complementation) experiments in Nicotiana benthamiana leaves. In addition, we have analyzed the effects of these interactions in the pathway of proanthocyanidin biosynthesis using the ANR (anthocyanidin reductase) gene promoter and the promoters of some of these genes (MYB4 and MYC1) fused with a luciferase reporter, together with the coexpression of the MBW genes using transient expression in Nicotiana benthamiana leaves. The results of these assays have confirmed the nuclear interaction of these genes and its role in the regulation of astringency biosynthesis, providing a basic model with some differences with respect to the models proposed in other species. / [CA] El cultiu del caqui ha crescut enormement en la regió Valenciana en els últims 20 anys al presentar-se com una alternativa interessant al cultiu de cítrics. No obstant, el seu cultiu s’enfronta a tres problemes importants. En primer lloc, la seua producció es monovarietal i està centrada en la varietat Rojo Brillante, el que suposa un risc sanitari i de mercat important que posa de manifest la necessitat de augmentar el nombre de varietats disponibles. En segon lloc, el canvi climàtic posa en perill la producció de caqui a la zona mediterrània degut a un augment en la salinitat del aigua i del sòl. La salinitat afecta de forma especialment al caqui degut al seus efectes sobre la producció, qualitat i vida post collita de la fruita. La falta de patrons tolerants a salinitat compatibles amb les condicions de cultiu a més agreuja aquest problema, pel que es necessari el desenvolupament de patrons clonals tolerants a salinitat. En tercer lloc, la industria del caqui esta basada en la aplicació de tractaments post collita de deastringència. Encara que existixen varietats naturalment no astringents, el seu us al mediterrani es complicat degut a la incompatibilitat en els patrons existents. A més, la salinitat afecta gravement a la eficàcia del tractament post collita de deastringència. Per això, cal destacar que es necessita conèixer millor els mecanismes moleculars que controlen el desenvolupament de la astringència per a la obtenció de noves varietats i/o uns tractaments post collita més efectius. En aquest context de millora genètica i biologia molecular, es poden distingir tres objectius per a millorar les condicions del cultiu en aquesta regió: el desenvolupament de noves varietats de caqui en una època de maduresa distinta a la de Rojo Brillante, el desenvolupament de patrons clonals tolerants a salinitat i compatibles amb varietats no astringents i la obtenció de nous coneixements sobre les bases moleculars del mecanisme de producció de astringència per optimitzar els tractaments post collita. La present tesi ha contribuït a aquests tres objectius. En el que respecta a la obtenció de noves varietats, s’ha desenvolupat un anàlisi de diversitat genètica del banc de germoplasma de l’IVIA, el qual es un recurs important per a la planificació de creuaments. Per a assegurar una millora genètica eficient i evitar redundàncies a la col·lecció, s’ha efectuat un anàlisi en microsatèl·lits. El anàlisi ha resultat en dades de gran utilitat, com el descobriment de al·lels únics, que permiteixen la identificació rapida de varietats, o la divisió de la col·lecció d’acord en el tipus d’astringència del fruit, confirmant el fons genètic comú de les accessions que comparteixen aquest caràcter. A més, el mapa de les relacions filogenètiques elaborat serà de gran utilitat per a la planificació futura de creuaments dins del programa de millora de caqui. Per a abordar el problema de la salinitat, s’han realitzat distints assajos d’estrés salí en hivernacle amb distintes poblacions de patró de caqui: Diospyros virginiana (tolerant a salinitat), Diospyros kaki (sensible a salinitat i amb compatibilitat) i Diospyros lotus (sensible a salinitat). A més, degut als caràcters de gran interès presents en aquestes dos espècies, es va incloure en els assajos una població provenient de un retrocreuament entre D. kaki i D. virginiana. Com a resultat, diversos individus d aquestes poblacions s’han seleccionat degut a la seua tolerància a salinitat, ja que podrien tindre les característiques adequades per a ser patrons clonals. Complementàriament, s’han utilitzat aproximacions fisiològiques, transcriptòmiques i de seqüenciació massiva de transcriptoma per a fer una primera descripció dels mecanismes de tolerància a salinitat presents en aquestes espècies. Com a resultat s’han descrit els principals caràcters relacionats amb la tolerància a la salinitat en el gènere Diospyros, com la compartimentalització de ions, la expressió en arrel de un gen similar a HKT-1, la abundància de canals de clorur o la arquitectura de la arrel. Finalment, per a obtenir mes informació sobre la biosíntesi de proantocianidines, la molècula responsable de la astringència, es va formular la hipòtesi de la existència de un complex proteic del tipus MBW (MYB-bHLH-WD40) que podria regular la ruta molecular de forma anàloga a la regulació existent en altres espècies estudiades. En primer lloc, es va seqüenciar el gen ortòlog putatiu del tipus WD40 de TTG1 de Arabidopsis thaliana. El paper de aquest gen i altres gens del hipotètic complex (MYB2, MYB4 i MYC1) han sigut estudiats mitjançant un anàlisi transcripcional en diferents estats de maduresa de fruits astringents i no astringents. A més, s’ha observat amb microscòpia la localització cel·lular de aquestos gens mitjançant la expressió transitòria amb fusió a fluorescència en fulles de Nicotiana benthamiana i hem analitzat la seua interacció amb un assaig de doble híbrid en llevat i BiFC (complementació bimolecular de fluorescència) mitjançant expressió transitòria en fulles de Nicotiana benthamiana. Finalment hem analitzat els efectes de aquests gens i de les seues interaccions en la ruta de biosíntesi de proantocianidines utilitzant el promotor del gen ANR (antocianidin reductasa) i promotors dels gens reguladors MYC1 i MYB4 fusionant-los amb una luciferasa com a gen delator i coexpressant-los amb diferents combinacions dels gens del complex MBW mitjançant expressió transitòria en fulles de Nicotiana benthamiana. Els resultats de aquests assajos confirmen la interacció nuclear de aquestos gens i el seu paper en la regulació de la producció de la astringència, donant lloc a un model bàsic amb algunes diferències als proposats en altres espècies. / Gil Muñoz, F. (2020). Biotechnological tools applied to the improvement of persimmon (Diospyros kaki Thunb) culture [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/153155 / TESIS

In many areas, over half of all diverted water is used for irrigation. Tree fruit crops use a lot of water, but water productivity can be increased using properly-timed precision water stress. In addition to water conservation, increases in water productivity arise from better fruit quality, increased storage life and reductions in pruning and maintenance. One major hurdle to applying precision water stress in orchards is the lack of a reliable, automated method of determining tree water status. However, the influence of physiological characteristics such as rootstock vigor on water productivity are also important. Selecting the most appropriate rootstocks and accurately determining the water status of orchard trees can increase water productivity. Research has shown that some rootstocks can more effectively extract water from soil. In this research, the response to water stress of three different Gisela tart cherry dwarfing rootstocks was compared using a weighing lysimeter system. Gisela 12 and Gisela 3 rootstocks recovered from drought stress more quickly and had higher trunk diameter growth rates than drought-stressed Gisela 5 rootstocks. Two potential methods of determining tree water status were also evaluated. Trunk hydration was measured using electromagnetic sensors and canopy temperature changes were detected using infrared radiometry. Electromagnetic techniques, including time domain reflectometry, can be used to determine the water content of wood. Until recently, the cost of this technology has inhibited its widespread use, but new affordable commercial electromagnetic soil moisture sensors have created renewed interest in this technique. In this research five different types of electromagnetic soil moisture sensors were inserted into the trunks of fruit trees and were monitored over two growing seasons. Maximizing exposure of waveguides to the sapwood increased the response of these sensors to changes in stem water potential. Infrared measurements of canopy temperature have successfully been used with field crops. However, the heterogeneity of orchard canopies makes this technique more difficult in orchards. Here, the efficacy of aiming radiometers at single trees versus at entire orchards was compared over multiple growing seasons. Neither single tree measurements nor whole orchard techniques produced a sufficiently robust signal to recommend them for general use.

Dans cette étude, nous avons dans un premier temps adapte le protocole d'embryogenèse somatique primaire a différentes variétés d'hybrides porte-greffes (3309C, 110R, Fercal, 41B et SO4) en nous appuyant sur l'expérience acquise au laboratoire sur Vitis vinifera cv Chardonnay. Les résultats montrent que le génotype, le type d'explant (étamine, fleur ou nœud), le type et la dose d'auxine utilisés dans le milieu d’induction (2,4-D ou 2,4,5-T) ont une influence sur les efficacités d'embryogenèse somatique. En effet, pour le 3309C, l'utilisation du 2,4,5-T dans le milieu d'induction a montré une efficacité embryogène supérieure à partir de nœuds par rapport à celle obtenue à partir d'étamines. Cependant la meilleure efficacité a été obtenue à partir de fleurs de cette variété, sur un milieu d'induction contenant du 2,4-D. De plus, le protocole d'embryogenèse somatique secondaire utilise de manière récurrente au laboratoire nous a permis d'obtenir des masses embryogènes ainsi que des embryons somatiques secondaires de ces porte-greffes. Le protocole de conversion des embryons en plantes, en présence de 4,5 uM de cytokinine (BAP) s'est avère efficace pour le 11OR et le 41B. Dans un second temps, nous avons co-cultivé le matériel embryogène obtenu pour quatre de ces génotypes (110R, 3309C, Fercal et 41B), avec Agrobacterium tumefaciens contenant trois constructions génétiques : (i) une copie d'une séquence partielle (1020 pb) du gène de la coque protéique du virus en orientation sens; (ii) une partie courte en sens et en anti-sens (280 pb) de cette même séquence formant une structure en épingle a cheveux (hpRNA = hairpin RNA) ; (iii) un amiRNA ciblant une séquence virale. Le gène bactérien codant la néomycine phosphotransférase et conférant la résistance à un antibiotique, la kanamycine, a été utilisé comme gène de sélection. Les conditions de sélection a la kanamycine ont nécessité des adaptations expérimentales telles que l’ajustement de la concentration en antibiotique puisque la sélection avec 75 mg.L-1 de kanamycine s'avère insuffisamment drastique dans Ia plupart de nos expériences de co-cullture. Les résultats d'analyse moléculaire par PCR ont montré l'amplification probable des fragments d'intérêt (CPGFLV et amiRI1TA-71) dans des échantillons de 11OR et de 41B résistants à la kanamycine. Cependant des analyses moléculaires supplémentaires par AL-PCR ne nous ont pas renseignées sur une éventuelle intégration du transgène amiRATA-71 dans des masses embryogènes de 41B. / In this study, we initially adapted the protocol of primary somatic embryogenesis in different varieties of hybrid rootstocks (3309C, 110R, Fercal, 41B and SO4) building on the experience gained in the laboratory on Vitis vinifera cv Chardonnay. The results show that the genotype, the explant type (stamen, flower or node), the type and the dose of auxin used in the induction medium (2,4-D or 2,4,5-T) influence the efficiency of somatic embryogenesis. Indeed, for the 3309C, the use of 2,4,5-T in the induction medium showed a higher efficiency from embryogenic nodes compared to that obtained from stamens. However, the better efficiency was obtained from the flowers of this variety on an induction medium containing 2,4-D. In addition, a protocol used in the laboratory for secondary somatic embryogenesis allowed us to obtain embryogenic masses as well as secondary somatic embryos from these rootstocks. The protocol conversion of embryos into plants, in the presence of 4.5 [tM of cytokinin (BAP), was effective for the 110R and 41B. In a second step, we co-cultivated embryogenic material obtained for four of these genotypes (110R, 3309C, Fercal and 41B), with Agrobacteriwn tumefaciens containing three genetic constructs: (i) a copy of a partial sequence (1020 bp) of the coat protein gene of the virus in the sense orientation, (ii) a short part-way and antisense (280 bp) of the same sequence forming a hairpin structure (hairpin RNA = hpRNA) (iii) one amiRNA targeting a viral sequence. The nptll bacterial gene encoding neomycin phosphotransferase and conferring resistance to the antibiotic kanamycin, was used as the selection gene. The selection conditions to kanamycin have required experimental adaptations such as adjusting the concentration of antibiotic because the selection with 75 mg.L-1 of kanamycin was not enough drastic in most of our experiments of co-culture. The results of molecular analysis by PCR showed probable amplification of fragments of interest (CPGFLV and amiRNA-71) in samples of 11OR and 41B resistant to kanamycin. However, additional molecular analysis by AL-PCR did not inform us about a possible integration of the transgene amiRNA-71 in embryogenic masses of 41B.

O tomateiro (Solanum lycopersicum L.) é uma das plantas cultivadas de maior importância no mundo, sendo uma das principais hortaliças em importância econômica no Brasil. A murcha-bacteriana é uma doença dentre as mais limitantes para a cultura do tomateiro e o uso de cultivares resistentes à Ralstonia spp. é uma das únicas alternativas para evitar as perdas causadas por esse patógeno. Contudo, existem raríssimos estudos sobre a base genética de genótipos resistentes aos principais isolados de Ralstonia spp. Objetivou-se nesse trabalho estudar parâmetros genéticos da resistência à murcha-bacteriana em linhagens e híbridos usados como porta-enxertos de tomateiro, por meio de abordagens complementares que envolvem desde o ajuste das metodologias para indução artificial da doença, até estimativas das capacidades de combinação e a heterose entre linhagens, visando identificar cruzamentos promissores para o estabelecimento de um programa de melhoramento genético para resistência à murcha-bacteriana em tomateiro para porta-enxertos. Comparando-se quatro métodos de indução da resistência verificou-se que o método da lesão das raízes do torrão com objeto cortante (bisturi) e pulverização de 5 mL da suspensão bacteriana no torrão, comparativamente aos outros métodos avaliados, apresenta fácil execução, requer quantidades reduzidas de suspensão bacteriana e proporciona boas quantidades de plantas de tomateiro com sintomas de murcha-bacteriana, sendo o mais adequado entre os métodos testados. Foi estimada a heterose e capacidade de combinação entre linhagens de tomateiro para um isolado do biovar 2 de Ralstonia solanacearum em estágio de plântulas, em ambiente protegido, e em um solo naturalmente infestado por Ralstonia spp. Entre as linhagens avaliadas, apenas o genótipo Hawaii 7996 apresentou níveis aceitáveis de resistência, sendo necessário encontrar novas fontes de resistência para o início de um programa de melhoramento. Verificou-se que nenhuma das progênies derivadas dos cruzamentos desse estudo apresentaram resistência superior ao parental superior Além disso, foi verificada a importância dos efeitos aditivos e, consequentemente, os cruzamentos de genitores com alta CGC para o caráter e a seleção recorrente seriam as melhores alternativas no melhoramento para resistência à murcha-bacteriana. Finalmente, foram estudados os genitores e seus híbridos, utilizados como porta-enxerto em condições de campo e em ambiente protegido visando o aumento da resistência à murcha-bacteriana causada por Ralstonia spp., e incremento dos parâmetros produtivos de um híbrido comercial utilizado como copa. Verificou-se influência dos diferentes porta-enxertos em caracteres de produção e massa dos frutos e no desenvimento de copa. Caracteres relacionados ao sistema radicular dos porta-enxertos apresentaram heterose em relação aos seus genitores, com efeitos aditivos e não aditivos importantes, mostrando o desempenho das linhagens e sua contribuição para a produção de híbridos superiores. Por fim, este estudo possibilitou o melhor entendimento sobre a base genética da resistência em genótipos de tomateiro que possuem uso potencial como porta-enxertos resistentes à murcha-bacteriana. / The tomato (Solanum lycopersicum L.) is one of the most important cultivated plants in the world, being one of the main vegetables of economic importance in Brazil. The bacterial wilt is one of the most limiting diseases for the tomato crop and the use of resistant cultivars to Ralstonia spp. is one of the only alternatives to avoid losses caused by this pathogen. However, there are very few studies on the genetic basis of genotypes resistant to the main isolates of Ralstonia spp. The objective of this work was to study the genetic parameters of resistance to bacterial wilt in lines and hybrids used as tomato rootstocks, through complementary approaches that range from the adjustment of the methodologies for artificial induction of the disease, to estimates of the combining abilities and heterosis among lines, aiming to identify promising crosses for the establishment of a rootstock genetic breeding program for resistance to bacterial wilt in tomatoes. Comparing four resistance induction methods, it was verified that the method of injuring roots with cutting object (scalpel) and spraying 5 mL of the bacterial suspension in the clod compared to the other\'s methods evaluated, is easiest to perform, requires less amounts of bacterial suspension and provides good amounts of tomato plants with wilt symptoms, being the most suitable among the methods tested. The heterosis and combining ability of tomato lines for a strain of biovar 2 of Ralstonia solanacearum in greenhouse at seedling stage and in soil naturally infested by Ralstonia spp were estimated. Among the lines evaluated, only the Hawaii 7996 genotype showed acceptable levels of resistance, and it is necessary to find new sources of resistance for the beginning of a breeding program. It was verified that none of the progenies derived from the crosses of this study presented superior resistance to the superior parental. In addition, the importance of the additive effects was verified and, consequently, the crossings of parents with high CGC for the character and the recurrent selection would be the best alternatives in the improvement for resistance to bacterial wilt. Finally, we studied the parents and their hybrids, used as rootstocks under field conditions and in a protected environment aiming the increasing resistance to bacterial wilt caused by Ralstonia spp., and increasing of the yield parameters of a commercial hybrid used as a scion. The influence of the different rootstocks was verified in characters of yield and mass of the fruits and in the development of the scion. Characteristics related to the root system of rootstocks showed heterosis in relation to their parents, with important additive and non-additive effects, showing the performance of the lines and their contribution to the production of superior hybrids. Finally, this study allowed a better understanding of the genetic basis of resistance in tomato genotypes that have potential use as bacterial wilt resistant rootstocks.

O tomateiro (Solanum lycopersicum L.) é uma das plantas cultivadas de maior importância no mundo, sendo uma das principais hortaliças em importância econômica no Brasil. A murcha-bacteriana é uma doença dentre as mais limitantes para a cultura do tomateiro e o uso de cultivares resistentes à Ralstonia spp. é uma das únicas alternativas para evitar as perdas causadas por esse patógeno. Contudo, existem raríssimos estudos sobre a base genética de genótipos resistentes aos principais isolados de Ralstonia spp. Objetivou-se nesse trabalho estudar parâmetros genéticos da resistência à murcha-bacteriana em linhagens e híbridos usados como porta-enxertos de tomateiro, por meio de abordagens complementares que envolvem desde o ajuste das metodologias para indução artificial da doença, até estimativas das capacidades de combinação e a heterose entre linhagens, visando identificar cruzamentos promissores para o estabelecimento de um programa de melhoramento genético para resistência à murcha-bacteriana em tomateiro para porta-enxertos. Comparando-se quatro métodos de indução da resistência verificou-se que o método da lesão das raízes do torrão com objeto cortante (bisturi) e pulverização de 5 mL da suspensão bacteriana no torrão, comparativamente aos outros métodos avaliados, apresenta fácil execução, requer quantidades reduzidas de suspensão bacteriana e proporciona boas quantidades de plantas de tomateiro com sintomas de murcha-bacteriana, sendo o mais adequado entre os métodos testados. Foi estimada a heterose e capacidade de combinação entre linhagens de tomateiro para um isolado do biovar 2 de Ralstonia solanacearum em estágio de plântulas, em ambiente protegido, e em um solo naturalmente infestado por Ralstonia spp. Entre as linhagens avaliadas, apenas o genótipo Hawaii 7996 apresentou níveis aceitáveis de resistência, sendo necessário encontrar novas fontes de resistência para o início de um programa de melhoramento. Verificou-se que nenhuma das progênies derivadas dos cruzamentos desse estudo apresentaram resistência superior ao parental superior Além disso, foi verificada a importância dos efeitos aditivos e, consequentemente, os cruzamentos de genitores com alta CGC para o caráter e a seleção recorrente seriam as melhores alternativas no melhoramento para resistência à murcha-bacteriana. Finalmente, foram estudados os genitores e seus híbridos, utilizados como porta-enxerto em condições de campo e em ambiente protegido visando o aumento da resistência à murcha-bacteriana causada por Ralstonia spp., e incremento dos parâmetros produtivos de um híbrido comercial utilizado como copa. Verificou-se influência dos diferentes porta-enxertos em caracteres de produção e massa dos frutos e no desenvimento de copa. Caracteres relacionados ao sistema radicular dos porta-enxertos apresentaram heterose em relação aos seus genitores, com efeitos aditivos e não aditivos importantes, mostrando o desempenho das linhagens e sua contribuição para a produção de híbridos superiores. Por fim, este estudo possibilitou o melhor entendimento sobre a base genética da resistência em genótipos de tomateiro que possuem uso potencial como porta-enxertos resistentes à murcha-bacteriana. / The tomato (Solanum lycopersicum L.) is one of the most important cultivated plants in the world, being one of the main vegetables of economic importance in Brazil. The bacterial wilt is one of the most limiting diseases for the tomato crop and the use of resistant cultivars to Ralstonia spp. is one of the only alternatives to avoid losses caused by this pathogen. However, there are very few studies on the genetic basis of genotypes resistant to the main isolates of Ralstonia spp. The objective of this work was to study the genetic parameters of resistance to bacterial wilt in lines and hybrids used as tomato rootstocks, through complementary approaches that range from the adjustment of the methodologies for artificial induction of the disease, to estimates of the combining abilities and heterosis among lines, aiming to identify promising crosses for the establishment of a rootstock genetic breeding program for resistance to bacterial wilt in tomatoes. Comparing four resistance induction methods, it was verified that the method of injuring roots with cutting object (scalpel) and spraying 5 mL of the bacterial suspension in the clod compared to the other\'s methods evaluated, is easiest to perform, requires less amounts of bacterial suspension and provides good amounts of tomato plants with wilt symptoms, being the most suitable among the methods tested. The heterosis and combining ability of tomato lines for a strain of biovar 2 of Ralstonia solanacearum in greenhouse at seedling stage and in soil naturally infested by Ralstonia spp were estimated. Among the lines evaluated, only the Hawaii 7996 genotype showed acceptable levels of resistance, and it is necessary to find new sources of resistance for the beginning of a breeding program. It was verified that none of the progenies derived from the crosses of this study presented superior resistance to the superior parental. In addition, the importance of the additive effects was verified and, consequently, the crossings of parents with high CGC for the character and the recurrent selection would be the best alternatives in the improvement for resistance to bacterial wilt. Finally, we studied the parents and their hybrids, used as rootstocks under field conditions and in a protected environment aiming the increasing resistance to bacterial wilt caused by Ralstonia spp., and increasing of the yield parameters of a commercial hybrid used as a scion. The influence of the different rootstocks was verified in characters of yield and mass of the fruits and in the development of the scion. Characteristics related to the root system of rootstocks showed heterosis in relation to their parents, with important additive and non-additive effects, showing the performance of the lines and their contribution to the production of superior hybrids. Finally, this study allowed a better understanding of the genetic basis of resistance in tomato genotypes that have potential use as bacterial wilt resistant rootstocks.

Made available in DSpace on 2014-06-11T19:26:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-12-20Bitstream added on 2014-06-13T20:54:59Z : No. of bitstreams: 1 junglaus_rw_me_botfca.pdf: 402477 bytes, checksum: 77f2aa9e503173f8168c0007cf5967ac (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Avaliou-se o efeito de reguladores vegetais em pepineiro, em um hibrido tipo japonês ‘Tsuyataro’, a campo e em ambiente de cultivo protegido, avaliando-se as aplicações de reguladores vegetais em plantas enxertadas e não enxertadas, sobre o número de frutos e peso de frutos comerciais e totais. Aplicou-se o Stimulate® em diferentes concentrações via foliar, aos 30 dias pós transplante. Observou-se aumentos significativos com a concentração de 375 mL de Stimulate® ha -1, para número de frutos, massa de frutos totais e comercias por metro quadrado em plantas não enxertadas. / Evaluate the effect of plant regulators in cucumber, in a hybrid type japanese 'Tsuyataro', the field and on environment of cultivation protected, evaluating the applications of regulators vegetable on plants grafted and non-grafted, above the number of fruit, and fruit weight and total trade. Applies is the Stimulate ®, in different concentrations merry way, at 30 days post transplant, is observed significant increases with the concentration of 375 mL of Stimulate ® ha -1, for number of fruit, total weight of fruits and total trade by square meter for non-grafted plants.

La Vigne est cultivée en système greffé, combinant les qualités de production fruitière des Vignes Européennes (Vitis vinifera) et la tolérance phylloxérique des Vignes Américaines (Vitis spp.). Cependant l’utilisation de porte-greffes américains modifie le développement, la physiologie, et l’alimentation hydrique et minérale du greffon. Plus particulièrement, le fond génétique des porte-greffes de la Vigne semble impliqué dans la régulation de la nutrition en phosphore (P) du greffon. Le phosphore est un élément nutritif essentiel pour la croissance des plantes, impliqué dans la composition de nombreux composants cellulaires, ainsi que dans le contrôle des voies métaboliques via son apport énergétique et la régulation de l’activité enzymatique. Malgré son importance, P un est des éléments minéraux les plus limitants pour la croissance des plantes en raison de sa faible disponibilité assimilable dans le sol. L’objectif de ce travail est de déterminer les mécanismes impliqués dans le contrôle de la nutrition en P de la Vigne, en comparant deux porte-greffes V. riparia cv. Riparia Gloire de Montpellier (RGM) et V. rupestris x V. berlandieri cv. 1103 Paulsen (1103P) connus pour conférer respectivement de faibles ou fortes concentrations en P à leur greffon. Les résultats montrent que 1103P est plus adapté à acquérir le P que RGM, en partie grâce à un système racinaire plus développé permettant une meilleure exploration du sol ainsi qu’une meilleure efficience d’acquisition du P disponible. Ce porte-greffe montre également meilleure utilisation de ses réserves en P dans les parties pérennes afin d’optimiser la croissance des parties aériennes. En revanche la capacité des génotypes à augmenter le P assimilable dans la rhizosphère ne semble pas être différente. Enfin l’effet du greffage et plus particulièrement du greffon a été étudié, révélant le rôle de V. vinifera sur le développement et le fonctionnement racinaire du porte-greffe. Ces résultats contribuent à la compréhension des mécanismes régulant l’alimentation minérale de la Vigne, mettant ainsi en évidence le rôle du fond génétique du porte-greffe sélectionné, ainsi que la régulation de ce dernier par son greffon. / Grapevine is grown in a grafted system, combining the fruit production qualities of the European species (Vitis vinifera) and the phylloxera tolerance of American species (Vitis spp.). However, the use of American rootstocks affects the development, the physiology, and the water and mineral status of the scion. Particularly, the genetic background of grapevine rootstocks appears to be involved in the regulation of phosphorus (P) content of the scion. Phosphorus is an essential nutrient for plant growth, involved in the composition of many cellular components, as well as in the control of metabolic pathways via its role in energy transfer and the regulation of enzymatic activity. Despite its importance, P is one of the most limiting mineral elements for plant growth because of its poor availability in the soil. The objective of this work is to determine mechanisms involved in the control of P nutrition in grapevine, by comparing two rootstocks V. riparia cv. Riparia Gloire de Montpellier (RGM) and V. rupestris x V. berlandieri cv. 1103 Paulsen (1103P) known to confer low and high concentrations of P to their scion respectively. The results show that 1103P is more efficient at acquiring P than RGM, with a higher developed root system allowing greater soil exploration as well as a higher efficiency of P acquisition. In addition, this rootstock shows better use of its reserves of P in perennial parts to optimize the growth of the shoot. However, the ability of genotypes to increase the assimilable P in the rhizosphere does not seem to be different. Finally, the effect of grafting, and more particularly of the scion genotype, has been studied, demonstrating the capacity of V. vinifera to alter the development and root functioning of the rootstock. These results contribute to our understanding of the mechanisms regulating the mineral nutrition in grapevine and highlight the role of the genetic background of the rootstock, as well as its regulation by the scion.

Les recherches sur les interactions porte-greffe/greffon chez la vigne en relation avec l’environnement perdurent depuis plusieurs décennies, mais les mécanismes physiologiques sous-jacents de la vigueur conférée sont toujours incompris. Ce manque de connaissance constitue un frein dans le développement des porte-greffes existants pour contrôler la vigueur et la productivité, ou dans la recherche de nouveaux génotypes de porte-greffe mieux adaptés aux conditions futures de production. L’objectif de ce travail est de comprendre par une approche de biologie intégrative couplant expérimentation et modélisation comment le porte-greffe interagit spécifiquement avec son greffon (et vice versa) pour modifier dès les premières étapes du greffage, les caractéristiques physiologiques de la plante entière afin de coordonner le développement et la croissance des parties aériennes avec celle des parties racinaires. L’azote étant considéré comme un élément-clef de contrôle de la croissance et de l’allocation de la biomasse au sein d’une plante, un accent particulier est porté sur le rôle de la nutrition azotée dans le contrôle trophique de la croissance du couple porte-greffe/greffon. Un travail expérimental en serre a été mené pour caractériser par marquage isotopique les flux d’azote (15N) et de carbone à l’échelle de la plante entière au sein de deux combinaisons de porte-greffe/greffon au stade végétatif : l’une conférant une forte vigueur (CS/1103P), l’autre une faible vigueur (CS/RGM), en réponse à une variation de la disponibilité externe en nitrate. Cette étude sur le couplage entre fonctions d’acquisition et d’utilisation des ressources azotées et carbonées a été complétée par un phénotypage dynamique de la croissance aérienne, de la répartition de biomasse entre les organes et de la composition biochimique et minérale des principaux organes de la plante. Nous avons ainsi pu appréhender les signaux de communication entre la partie aérienne et la partie racinaire de la vigne greffée, ce qui a abouti à l’élaboration d’un modèle conceptuel simplifié du fonctionnement de la vigne greffée. Une première version d’un modèle mécaniste basé sur un formalisme source-puits prenant en compte l’acquisition et l’allocation de C et N au sein de deux compartiments aérien et racinaire, ainsi que leur plasticité vis-à-vis de la disponibilité exogène et endogène en ressources a été élaborée. A terme, le modèle devrait permettre d’identifier des paramètres génétiques clef au niveau racinaire explicitant les différences de croissance et vigueur conférée observées selon les combinaisons porte-greffe/greffon / Research on rootstock/scion interactions in grapevine in relation to the environment persisted for several decades, but the physiological mechanisms determining the rootstock effect on scion vigour are still misunderstood. This lack of knowledge hampers the development of existing rootstocks to control the vigor and productivity, or research new rootstock genotypes better adapted to future conditions of production. The objective of this work is to understand by an integrative biology approach coupling experimentation and modeling how the rootstock interacts specifically with the scion (and vice versa) to change in the early stages of grafting , the physiological characteristics of the whole plant to coordinate the development and growth of the aerial parts with the root parties. Nitrogen is considered a key element in the control of the growth and the biomass allocation within a plant, and a particular emphasis is placed on the role of nitrogen nutrition in the nutritional control of the grafted grapevine growth. Experimental work was conducted in a greenhouse to characterize by isotopic labeling nitrogen (15N) and carbon flow within the whole plant for two rootstock/scion combinations at vegetative stage : one giving a strong vigour (CS/1103P), the other a low vigour (CS / RGM), in response to a change in the external nitrate availability. This study on the coupling between acquisition functions and use of nitrogenous and carbonaceous resources was completed by a dynamic phenotyping aerial growth, the distribution of biomass between the organs and the biochemical and mineral composition of the principal organs of plant. We were able to understand the communication signals between the aerial part and the root part of grafted vines, which led to the development of a simplified conceptual model of the functioning of the grafted vines. A first version of a mechanistic model based on a source-sink formalism taking into account the acquisition and allocation of C and N in both aerial and root compartments and their plasticity to the availability of exogenous and endogenous resource was developed.

Submitted by Maria Beatriz Vieira (mbeatriz.vieira@gmail.com) on 2017-06-21T15:10:36Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_camila_fernanda_junkes.pdf: 1289430 bytes, checksum: c3ed40aa6f1d8b5187b0894e8ea77b9b (MD5) / Approved for entry into archive by Aline Batista (alinehb.ufpel@gmail.com) on 2017-06-21T18:58:38Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_camila_fernanda_junkes.pdf: 1289430 bytes, checksum: c3ed40aa6f1d8b5187b0894e8ea77b9b (MD5) / Made available in DSpace on 2017-06-21T18:58:38Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_camila_fernanda_junkes.pdf: 1289430 bytes, checksum: c3ed40aa6f1d8b5187b0894e8ea77b9b (MD5) Previous issue date: 2015-02-26 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / A macieira é uma frutífera lenhosa amplamente difundida no mundo. Suas mudas são propagadas por estaquia e os porta-enxertos por mergulhia de cepa devido ao alto grau de incompatibilidade entre os genótipos e grande período de juvenilidade. Os porta-enxertos conferem diferenças no vigor e resistência a doenças à cultivar copa, sendo mais utilizadas no Brasil as cultivares M.9 (anão) e ‘Marubakaido’ (vigoroso). Devido a problemas fitossanitários e de rendimento da técnica de propagação vegetativa, a micropropagação surge como uma tecnologia útil tanto a nível de pesquisa quanto a nível comercial. No entanto, cada genótipo de macieira responde de forma diferente aos estímulos in vitro, de forma que deve-se adequar os protocolos em função da cultivar em estudo. Neste sentido, o presente trabalho teve como objetivo traçar os primeiros estudos sobre a utilização de sistema de imersão temporária (SIT) na micropropagação de ‘Marubakaido’. Para tal, testes preliminares sobre a influência do tipo de explante (apical ou axilar) foram realizados via sistema convencional em três variações do meio MS (composição convencional; NH4NO3 e KNO3 reduzido a ¾; e formulação industrial Himedia) suplementados com 0,8 mg.L-1 de BAP, 100 mg.L-1 de mio-inositol, 30 g.L-1 de sacarose e 7 g.L-1 de ágar. Após 45 dias observou-se que o meio Himedia conferiu maior homogeneidade entre as brotações, enquanto o tipo de explante não afetou a resposta quanto ao número e comprimento médio das brotações obtidas, podendo ambos serem utilizados sem prejuízo às taxas de multiplicação. Em seguida, os mesmos meios foram empregados na comparação entre micropropagação de explantes axilares de ‘Marubakaido’ em sistema convencional e SIT. Após 4 semanas verificou-se que as taxas de hiperidricidade obtidas em SIT foram muito mais elevadas do que em sistema convencional, chegando a 100% para meio MS. Uma intensa formação de calos foi observada nos meios MS e MS ¾ neste mesmo sistema, que impediram o desenvolvimento dos explantes. Quanto ao número médio e comprimento de brotações, o meio Himedia em SIT apresentou melhores resultados quando comparado a todos os tratamentos para meio e sistema (6,3 brotações por explante e 3,7 cm). O enraizamento das brotações produzidas em SIT com meio Himedia foi maior quando as brotações foram destacadas se comparadas com brotações mantidas em tufos (74,1% e 62,5% respectivamente), e a aclimatização das microestacas enraizadas resultou em 88,5% de sobrevivência após 21 dias. Embora os resultados tenham sido promissores, novos estudos ainda precisam ser realizados na tentativa de aperfeiçoar estes protocolos para ‘Marubakaido’, como alterações na composição hormonal, tempo e frequência de passagem do meio para os explantes ou enraizamento ao abrigo de luz. / The apple tree is a woody fruit widespread in the world. Your plants are propagated by cuttings and rootstocks by layering strain due to the high level of incompatibility between the genotypes and great period of juvenility. Rootstocks confer differences in vigor and disease resistance to scion, being more used in Brazil the cultivars M.9 (dwarf) and 'Marubakaido' (vigorous). Due to phytosanitary problems and yield of vegetative propagation technique, micropropagation appears as a useful technology at level of research or commercially. However, each apple genotype responds differently to in vitro stimuli, so the protocols must be adapted according to cultivar in study. Herewith, the present research aimed to draw the first studies about the use of temporary immersion system (TIS) in ‘Marubakaido's micropropagation. For this purpose, preliminary tests about the influence of the type of explant (apical or axillary) were performed via conventional system in three variations of the MS media (conventional composition; NH4NO3 and KNO3 reduced to ¾, and industrial formulation Himedia) supplemented with 0.8 mg.L-1 BAP, 100 mg L-1 myo-inositol, 30 g L-1 sucrose and 7 g L-1 agar. After 45 days it was observed that the Himedia conferred greater homogeneity among the shoots, while the type of explant did not affect the response in the average of number and length of shoots obtained, and both can be used without prejudice to the multiplication rates. Then, the same media were used in the comparison of micropropagation of ‘Marubakaido’ axillary explants between conventional system and TIS. After 4 weeks it was found that the hyperhydricity rates obtained with TIS were much higher than in conventional system, reaching 100% at MS medium. An intense callus formation was observed in MS and MS ¾ media at same system, which stopped the development of the explants. For the mean of number and length shoots, the Himedia composition in TIS showed better results when compared to all treatments for media and system (6.3 shoots per explant and 3.7 cm). Rooting of shoots produced in TIS with Himedia was higher when the shoots were separated compared with shoots kept in tufts (74.1% and 62.5% respectively), and acclimatization of the rooted microcutting resulted in 88.5% of survival after 21 days. Although the results have been promising, further studies still need to be performed to improve these protocols to ‘Marubakaido’, as changes in hormonal composition, time and frequency for passage of media to the explants or rooting under darkness.

Considerando o sistema atual de produção de mudas cítricas, este trabalho teve como objetivo estudar os efeitos de diferentes níveis de irrigação e fertirrigação sobre o crescimento do porta-enxerto citrumelo 'Swingle' (Citrus paradisi x Poncirus trifoliata), propondo modelos matemáticos para se descrever estas interações, e desenvolver, construir e analisar a performance de dois lisímetros móveis de pesagem, utilizando-se célula de carga confeccionada com cilindro hidráulico em um e diafragma no outro. A primeira fase deste trabalho foi realizada utilizando-se porta-enxertos cultivados em container com substrato, sob condições de ambiente protegido, em um viveiro comercial situado no município paulista de Rio Claro. Utilizou-se o delineamento balanceado para vizinhança, composto por oito blocos, cada um com quatro linhas e quatro colunas, constituído-se 16 tratamentos, através da combinação de dois fatores, irrigação e fertirrigação. Foram avaliados os efeitos de níveis de irrigação e nutrientes sobre a taxa de crescimento relativo do porta-enxerto. Os resultados obtidos neste trabalho permitiram concluir que o volume total de água de 9,838L.planta-1, distribuídos ao longo dos 71 dias, e o fornecimento de (mg.planta-1) 468,6 de NO3, 20,9 de N-NH4, 49,5 de P, 358,7 de K, 361,6 de Ca, 64,2 de Mg, 2,59 de Cu, 3,93 de Zn, 3,93 de Mn, 16,49 de Fe e 0,05 de Mo, parcelado em 21 fertirrigações, promoveram a maior precocidade de formação do porta-enxerto, quando comparados aos demais níveis. Os modelos matemáticos TCRD = 0,004636316 + 0,00001313791L - 0,00001160437N e TCRA = 0,03357119 + 0,00002852342L - 0,0007466065N + 0,000007850791N2 - 0,00000002718364N3, foram validados, sento TCRD e TCRA a taxa de crescimento relativo, em função do diâmetro e altura do caule, respectivamente, L e N uma porcentagem da quantidade de água e nutrientes, a ser aplicada, respectivamente. A segunda fase deste trabalho foi realizada no Departamento de Engenharia Rural, pertencente à Escola Superior de Agricultura "Luiz de Queiroz" - ESALQ/USP, em Piracicaba, SP. A solução encontrada para se viabilizar a lisimetria em casa de vegetação, com grupos de plantas muito heterogêneos, foi o emprego de uma estrutura móvel capaz de pesar, isoladamente, vários Contentores de Mudas. O número de contentores seria diretamente proporcional ao número de variedades cultivadas e estádio de desenvolvimento, enquanto que o número de estruturas móveis de pesagem seria função do número de contentores a ser pesado em um dado período. Concluiu-se neste trabalho que o lisímetro com cilindro hidráulico apresentou um desempenho insatisfatório, devido à detecção de histerese e lentidão de resposta. Todavia, o emprego de um diafragma proporcionou um desempenho superior ao do cilindro hidráulico, resultando na equação matemática V=0,0178.LR, onde V é o volume de água (L.planta-1) e LR é a leitura piezométrica (mm). Esta equação apresentou um r2 de 0,9971, indicando a excelente precisão do equipamento. Com um r2 de 0,9975, originado da regressão entre o volume estimado e volume real, e um índice de Concordância (d) de 0,99926, o lisímetro apresentou excelente acurácia, com resolução de 0,45mm de lâmina de água. Sua mobilidade permitiu o livre deslocamento entre bancadas de mudas, exigindo um único operador. O custo total estimado de construção de cada lisímetro foi de US$1.108,54. / The objective of this experiment was to evaluate the effects of different levels of irrigation and fertirrigation on the growth of the citrumelo ‘Swingle’ (Citrus paradisi x Poncirus trifoliata) rootstock, establishing mathematical models to describe these interactions and develop, construct and evaluate the performance of two movable weighing lysimeter, applying a hydraulic load cell made of hydraulical cylinder and diaphragm. The first trial studied the vegetative growth of containerized citrus rootstock, in a commercial screenhouse situated in Rio Claro, São Paulo State, Brazil. The experiment used the neighbor balanced design, composition of eight blocks, each one with four lines and four columns, consisting of 16 treatments, through the combination of two factors: irrigation and fertirrigação. The effect of irrigation and nutrients levels on the relative growth rate of rootstock was evaluated. The results showed that the water total of 9.838L/plant, distributed in 71 days, and the supply of (mg/plant) 468.6NO3, 20.9NNH4, 49.5P, 358.7K, 361.6Ca, 64.2Mg, 2.59Cu, 3.93Zn, 3.93Mn, 16.49Fe e 0.05Mo, split application in 21 fertirrigation, promoted the precocity growth of rootstock, when compared with the other levels. The mathematical models was been validated, resulting in: TCRD = 0,004636316 + 0,00001313791L - 0,00001160437N and TCRA = 0,03357119 + 0,00002852342L - 0,0007466065N + 0,000007850791N2 - 0,00000002718364N3 with TCRD and TCRA being the relative growth rate as a function of diameter and height, respectively, L and N were the percentage of the amount of water and nutrients applied, respectively. The second trial was conducted at the Department of Agricultural Engineering, at the Escola Superior de Agricultura "Luiz de Queiroz" - ESALQ/USP, in Piracicaba, São Paulo State, Brazil. The solution was to make a feasible use of lysimeter in actual citrus nursery production system in screenhouse, with high heterogeneous group of plants, was to use a movable structure, able to weight several containers of seedlings, sequentially. The number of container was function of number of varieties and development stage. The number of weighing structure was a function of the number of containers. From results, it was concluded that lysimeter with hydraulical cylinder presented an unsatisfactory performance, due to hysteresis and slowness of reply. However, the lysimeter with diaphragm presented a good performance, providing the mathematic equation V=0.0178LR, where V is the volume of water (L/plant) and LR is the piezometric reading (mm). The determination coefficient (r2,) was 0.9971, indicating an excellent adjustment of equipment. A regression between estimated and real volume, provide a r2 of 0.9975 and Concordance Index (d) of 0.99926, indicated a excellent accuracy, with 0.45mm water depth resolution. The mobility of equipment allowed free movement between nursery benches, with just one operator. Total construction cost was US$1,108.54, for each lysimeter.