Exploring sources of resistance to brown rot in an interspecific almond × peach population

BACKGROUND: Monilinia spp. are responsible for brown rot, one of the most significant stone fruit diseases. Planting resistant cultivars seems a promising alternative, although most commercial cultivars are susceptible to brown rot. The aim of this study was to explore resistance to Monilinia fructicola over two seasons in a backcross one interspecific population between almond ‘Texas’ and peach ‘Earlygold’ (named T1E). RESULTS: ‘Texas’ almond was resistant to brown rot inoculation, whereas peach was highly susceptible. Phenotypic data from the T1E population indicated wide differences in response to M. fructicola. Additionally, several non-wounded individuals exhibited resistance to brown rot. Quantitative trait loci (QTLs) were identified in several linkage groups, but only two proximal QTLs in G4 were detected over both seasons and accounted for 11.3–16.2% of the phenotypic variation. CONCLUSION: Analysis of the progeny allowed the identification of resistant genotypes that could serve as a source of resistance in peach breeding programs. The finding of loci associated with brown rot resistance would shed light on implementing a strategy based on marker-assisted selection (MAS) for introgression of this trait into elite peach materials. New peach cultivars resistant to brown rot may contribute to the implementation of more sustainable crop protection strategies.info:eu-repo/semantics/acceptedVersio

Experimental study of the atomisation and combustion of ionic green monopropellant prototypes for a satellite propulsion system application.

La mise et le maintien à poste des satellites sont encore largement réalisés à l’aide de propulseurs chimiques tels que les moteurs bi-liquides NTO/MMH (tetroxyde d’azote / monomethylhydrazine) et les moteurs catalytiques à hydrazine. Toutefois, en raison de son caractère CMR (Cancérogène, Mutagène, Reprotoxique) suspecté chez l’homme, l’Agence Européenne des produits CHimiques (ECHA) a placé l’hydrazine sur la liste des « substances très préoccupantes » via le processus REACh (Registration, Evaluation, Autorisation and restriction of Chemicals).Afin de trouver un remplaçant à ce produit énergétique de nombreux pays ont décidé de rechercher de nouveaux systèmes propulsifs chimiques "verts", c’est-à-dire à toxicité réduite, et présentant desperformances accrues, notamment à base de Liquides Ioniques Energétiques (LIE). En France, c’est particulièrement le cas du CNES et de l’ONERA qui ont lancé en 2016 un « Projet d’Intérêt Commun Propulsion Monergol Vert » (PIC PMV). Le présent travail de thèse s’inscrit dans ce projet et poursuit les travaux notamment initiés par Quentin Levard dans sa thèse : « Étude expérimentale et numérique de la décomposition d'un liquide ionique énergétique pour le développement d'un propulseur à monergol vert ».Dans ce travail de thèse nous reprenons cette recherche en nous focalisant sur les deux axes capitaux présents lors de l’allumage et la combustion d’un spray : l’atomisation non-réactive et l’allumage de gouttes isolées. Ainsi, concernant l’étude de l’atomisation, nous avons développé un banc permettant la mesure simultanée de la granulométrie et de l’angle de spray en fonction de la pression d’injection. Enfin, nous avons comparé ces résultats granulométriques avec des relations empiriques issues de la littérature afin de tenter de parvenir à une prédiction fiable de ceux-ci. Ensuite, concernant l’étude de l’allumage et de la combustion de gouttes isolées, nous avons là-aussi développé un banc permettant la visualisation synchrone et superposable de l’allumage d’une goutte en UV et visible. Ce banc nous a notamment permis de confirmer de façon univoque la combustion de monergol vert ainsi que le type de flamme engendré. Pour conclure, nous avons utilisé les connaissances acquises au travers de ces deux axes pour concevoir et mettre à feu un prototype de chambre de combustion à monergol vert ionique.The positioning and maintenance of satellites are still largely carried out using chemical thrusters such as NTO/MMH (nitrogen tetroxide / monomethylhydrazine) bi-liquid engines and hydrazine catalytic engines. However, due to its suspected Carcinogenic, Mutagenic, and Reprotoxic (CMR) properties in humans, the European CHemicals Agency (ECHA) has placed hydrazine on the list of "substances of very high concern" via the REACh (Registration, Evaluation, Authorisation and restriction of Chemicals) process.In order to find a replacement for this energetic product, many countries have decided to search for new "green" chemical propulsion systems, i.e. with reduced toxicity and improved performance, notably based on Energetic Ionic Liquids (EIL). In France, this is particularly the case for CNES and ONERA, who launched a "Green Monopropellant Propulsion Common Interest Project" (PIC PMV) in 2016. This thesis work is part of this project and continues the work initiated in particular by Quentin Levard in his thesis: "Experimental and Numerical Study of the Decomposition of an Energetic Ionic Liquid for the Development of a Green Monopropellant Thruster".In this thesis work, we resume this research by focusing on the two key axes present during the ignition and combustion of a spray: the non-reactive atomisation and the ignition of isolated droplets. Regarding the non-reactive atomisation, we have developed a bench allowing the simultaneous measurement of the droplet size distribution and the spray angle as a function of the injection pressure. Finally, we have compared these droplet size distribution results with empirical relationships from the literature to attempt to achieve a reliable prediction of these. Next, regarding the study of ignition and combustion of isolated droplets, we have also developed a bench allowing the synchronous and super-imposable visualisation of the ignition of a droplet in UV and visible light. This bench has notably allowed us to unambiguously confirm the combustion of green monopropellant as well as the type of flame generated. To conclude, we have used the knowledge acquired through these two axes to design and ignite a prototype of an ionic green monopropellant combustion chamber

Parallel Multi-Block Computations of Three-Dimensional Incompressible Flows

Parallel computation has shown to provide considerable potential for the numerical simulation of complex three-dimensional flows. A number of studies have shown that CFD codes can be parallelized for efficient use on present-day parallel computer systems. However, of particular importance for industrial applications is the total time to solution, comprised not only of the resolution of the flow equations but also the pre- and post-processing phases. Results are presented of a study of the use of high-performance parallel computing to facilitate such numerical simulations. This study is being undertaken using a 256-processor Cray T3D system, within the framework of the joint Cray Research--EPFL Parallel Application Technology Program. 1 FLOW SOLVER The parallel code used in this study is based on a multi-block code developed within IMHEF-EPFL for the numerical simulation of unsteady, turbulent, incompressible flows. This code solves the Reynolds-averaged Navier-Stokes equations on 3D ..