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Allopolyploids undergo 'genomic shock' leading to significant genetic and epigenetic modifications. Previous studies have mainly focused on nuclear changes, while little is known about the inheritance and changes of organelle genome in allopolyploidization. The synthetic allotetraploid Cucumis *hytivus, which is generated via hybridization between C. hystrix and C. sativus, is a useful model system for studying cytonuclear variation. Here, we report the chloroplast genome of allotetraploid C. *hytivus and its diploid parents via sequencing and comparative analysis. The size of the obtained chloroplast genomes ranged from 154 673 to 155 760 bp, while their gene contents, gene orders, and GC contents were similar to each other. Comparative genome analysis supports chloroplast maternal inheritance. However, we identified 51 indels and 292 SNP genetic variants in the chloroplast genome of the allopolyploid C. *hytivus relative to its female parent C. hystrix. Nine intergenic regions with rich variation were identified through comparative analysis of the chloroplast genomes within the subgenus Cucumis. The phylogenetic network based on the chloroplast genome sequences clarified the evolution and taxonomic position of the synthetic allotetraploid C. *hytivus. The results of this study provide us with an insight into the changes of organelle genome after allopolyploidization, and a new understanding of the cytonuclear evolution. Key words: allopolyploidy, chloroplast genome, SNP, phylogenetic analysis, Cucumis. Les allopolyploides subissent 'choc genomique' menant a d'importants changements genomiques et epigenetiques. Les etudes anterieures ont principalement documente les changements nucleaires, tandis que peu de choses sont connues de l'heredite et des changements dans l'organisation du genome des organites lors de l'allopolyploidisation. L'allopolyploide synthetique Cucumis *hytivus, lequel est genere par hybridation entre le C. hystrix et le C. sativus, est un modele utile pour etudier la variation cytonucleaire. Dans ce travail, les auteurs examinent le genome chloroplastique de l'allotetraplo'ide C. *hytivus et de ses parents diploides via le sequencage et des analyses comparees. La taille des genomes chloroplastiques obtenus variait entre 154 673 et 155 760 pb, tandis que le contenu genique, leur ordre ainsi que le contenu en GC etaient semblables. Une analyse comparee des genomes confirme la transmission maternelle du chloroplaste. Cependant, les auteurs ont identifie 51 indels et 292 variants SNP dans le genome chloroplastique de l'allopolyploide C. *hytivus par rapport a celui du parent femelle C. hystrix. Neuf regions intergeniques riches en variation ont ete identifiees via analyse comparee des genomes chloroplastiques au sein du sous-genre Cucumis. Le reseau phylogenetique fonde sur les sequences de genomes chloroplastiques a clarifiel'evolution et la position taxonomique de l'allotetraploide C. *hytivus. Les resultats de cette etude jettent un eclairage sur les changements qui surviennent dans les genomes des organites apres allopolyploidisation et contribuent a une meilleure comprehension de l'evolution cytonucleaire. [Traduit par la Redaction] Mots-cles : allopolyploidie, genome chloroplastiqu, SNP, analyse phylogenetique, Cucumis., Introduction Allopolyploids, formed by interspecific hybridization and whole-genome duplication (WGD), have played a key role in the evolution of plant species (Leitch and Bennett 1997; Soltis et al. 2009; Wendel [...]

Deep eutectic solvents (DESs) have been synthesized by using N, N, N -trimethyl propylsulphonate ammonium hydrosulfate as the hydrogen bond acceptor (HBA) and urea as hydrogen bond donor (HBD) in capricious molar ratios. Fourier transform infrared spectrum, the proton nuclear magnetic resonance and carbon-13 nuclear magnetic resonance are employed to confirmed the chemical structures of N, N, N -trimethyl propylsulphonate ammonium hydrosulfate. The synthesized DESs are characterized by thermogravimetric analysis and Fourier transform infrared spectrum. The synthesized DESs exhibit excellent thermal stability, making them suitable electrolytes for proton exchange membrane fuel cell. The viscosity and conductivity of DESs are significantly affected by the molar ratio between HBD and HBA. The four samples are used as electrolytes to evaluate the fuel cell performance. The results indicate that the power density of the four samples decreases in the following order: DES with a molar ratio of HBA/HBD of 1:1 > DES with a molar ratio of HBA/HBD of 2:1 > N, N, N -trimethyl propylsulphonate ammonium hydrosulfate > DES with a molar ratio of HBA/HBD of 1:2. The DES with a molar ratio of HBA/HBD of 1:1 exhibits a significantly higher peak power density of 92.5 mW · cm−2 compared to the peak power density (48.5 mW · cm−2) observed without the addition of urea at 50 °C, while DES with a molar ratio of HBA/HBD of 1:2 displays a much lower peak power density of only 8.7 mW · cm−2 at 30 °C. The proton diffusion coefficient D is a critical factor that significantly impacts fuel cell performance. DESs as proton conducting media is a promising approach to improve cell performance in the proton exchange membrane fuel cell. • DES with N3-1-0 & urea (1:1) as electrolyte obtains highest power density. • DESs are thermally stable and ideal for fuel cell electrolytes. • The proton diffusion coefficient D greatly affects fuel cell performance. [ABSTRACT FROM AUTHOR]