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Genetic diversity of alfalfa (Medicago sativa) in response to temperature during germination
No full textTemperature is one of the major factors controlling plant development, in particular seed germination. Alfalfa
is a perennial pasture legume that holds an important place in cultivated grasslands. Breeding alfalfa cultivars
adapted to new ranges of temperature could be necessary, requiring knowledge of the variability in response
to temperature among different accessions. Six accessions of Medicago sativa subsp. sativa and one wild
population of M. sativa subsp. falcata were evaluated for their germination temperature response. Seeds were
tested for germination in the dark at eight constant temperatures, from 5 to 40°C. Significant differences
(P < 0.01) were found. The optimum temperature for germination ranged between 11.7 and 21.1°C, whereas
two varieties, ‘Demnate’ and ‘Luzelle’ had a very wide range of temperatures favouring maximum germination.
The findings of this study suggest that the germination of alfalfa was little affected by low temperature (5°C)
whereas germination at 40°C was lower and showed high variability. Our results revealed variability in the
response to temperature for germination of M. sativa that gives room for breeding new varieties adapted to
future environmental conditions induced by the global climate change
Expression of vaspin and GRP78 in corpus luteum are dependent on estrous phase in Large White pigs
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A Comprehensive Review of Non-Covalent Radiofluorination Approaches Using Aluminum [18F]fluoride: Will [18F]AlF Replace 68Ga for Metal Chelate Labeling?
No full textDue to its ideal physical properties, fluorine-18 turns out to be a key radionuclide for positron emission tomography (PET) imaging, for both preclinical and clinical applications. However, usual biomolecules radiofluorination procedures require the formation of covalent bonds with fluorinated prosthetic groups. This drawback makes radiofluorination impractical for routine radiolabeling, gallium-68 appearing to be much more convenient for the labeling of chelator-bearing PET probes. In response to this limitation, a recent expansion of the 18F chemical toolbox gave aluminum [18F]fluoride chemistry a real prominence since the late 2000s. This approach is based on the formation of an [18F][AlF]2+ cation, complexed with a 9-membered cyclic chelator such as NOTA, NODA or their analogs. Allowing a one-step radiofluorination in an aqueous medium, this technique combines fluorine-18 and non-covalent radiolabeling with the advantage of being very easy to implement. Since its first reports, [18F]AlF radiolabeling approach has been applied to a wide variety of potential PET imaging vectors, whether of peptidic, proteic, or small molecule structure. Most of these [18F]AlF-labeled tracers showed promising preclinical results and have reached the clinical evaluation stage for some of them. The aim of this report is to provide a comprehensive overview of [18F]AlF labeling applications through a description of the various [18F]AlF-labeled conjugates, from their radiosynthesis to their evaluation as PET imaging agents
Innovative microscale workflow from fungi cultures to Cell Wall-Degrading Enzyme screening
No full textThis study aimed at developing a complete miniaturized high-throughput screening workflow for the evaluation of the Cell Wall-Degrading Enzyme (CWDE) activities produced by any fungal strain directly cultivated on raw feedstock in a submerged manner. In this study, wheat straw was selected as model substrate as it represents an important carbon source but yet poorly valorised to yield high added value products. Fungi were grown in a microbioreactor in a high-throughput (HT) way to replace the fastidious shaking flask cultivations. Both approaches were compared in order to validate our new methodology. The range of CWDE activities produced from the cultures was assayed using AZO-died and pNP-linked substrates in an SBS plate format using a Biomek FXp pipetting platform. As highlighted in this study, it was shown that the CWDE activities gathered from the microbioreactor cultivations were similar or higher to those obtained from shake flasks cultures, with a lower standard deviation on the measured values, making this new method much faster than the traditional one and suitable for HT CWDE production thanks to its pipetting platform compatibility. Also, the results showed that the enzymatic activities measured were the same when doing the assay manually or using the automated method
Phylogenetic Origin of Primary and Secondary Metabolic Pathway Genes Revealed by C. maxima and C. reticulata Diagnostic SNPs
No full textModern cultivated Citrus species and varieties result from interspecific hybridization between four ancestral taxa. Among them, Citrus maxima and Citrus reticulata, closely associated with the pummelo and mandarin horticultural groups, respectively, were particularly important as the progenitors of sour and sweet oranges (Citrus aurantium and Citrus sinensis), grapefruits (Citrus paradisi), and hybrid types resulting from modern breeding programs (tangors, tangelos, and orangelos). The differentiation between the four ancestral taxa and the phylogenomic structure of modern varieties widely drive the phenotypic diversity’s organization. In particular, strong phenotypic differences exist in the coloration and sweetness and represent important criteria for breeders. In this context, focusing on the genes of the sugar, carotenoid, and chlorophyll biosynthesis pathways, the aim of this work was to develop a set of diagnostic single-nucleotide polymorphism (SNP) markers to distinguish the ancestral haplotypes of C. maxima and C. reticulata and to provide information at the intraspecific diversity level (within C. reticulata or C. maxima). In silico analysis allowed the identification of 3,347 SNPs from selected genes. Among them, 1,024 were detected as potential differentiation markers between C. reticulata and C. maxima. A total of 115 SNPs were successfully developed using a competitive PCR technology. Their transferability among all Citrus species and the true citrus genera was very good, with only 0.87% of missing data. The ancestral alleles of the SNPs were identified, and we validated the usefulness of the developed markers for tracing the ancestral haplotype in large germplasm collections and sexually recombined progeny issued from the C. reticulata/C. maxima admixture gene pool. These markers will pave the way for targeted association studies based on ancestral haplotypes
A secreted metal-binding protein protects necrotrophic phytopathogens from reactive oxygen species
No full textFew secreted proteins involved in plant infection common to necrotrophic bacteria, fungi and oomycetes have been identified except for plant cell wall-degrading enzymes. Here we study a family of iron-binding proteins that is present in Gram-negative and Gram-positive bacteria, fungi, oomycetes and some animals. Homolog proteins in the phytopathogenic bacterium Dickeya dadantii (IbpS) and the fungal necrotroph Botrytis cinerea (BcIbp) are involved in plant infection. IbpS is secreted, can bind iron and copper, and protects the bacteria against H2O2-induced death. Its 1.7 angstrom crystal structure reveals a classical Venus Fly trap fold that forms dimers in solution and in the crystal. We propose that secreted Ibp proteins binds exogenous metals and thus limit intracellular metal accumulation and ROS formation in the microorganisms
Développer des alternatives à des systèmes de culture Maïs-Blé en polyculture-élevage sans irrigation : enseignements de trois expérimentations conduites dans différentes régions françaises.
No full textTrois systèmes de culture expérimentaux, alternatifs à un système local dominant à base de Maïs-Blé
non irrigué, dans un contexte de polyculture-élevage, partagent le même objectif principal de diminuer
de 50% l’Indice de Fréquence de Traitement (IFT) par rapport au système local dominant tout en
maintenant la rentabilité. Les résultats pluriannuels montrent une diminution de 22 à 50% de l’IFT total,
de 55 à 80% de l’IFT hors herbicide, de 12 à 65% de l’IFT herbicide. Les systèmes présentent aussi
des risques d’exposition toxique de l’agriculteur plus faibles et des risques de transfert de substances
actives vers l’environnement plus faibles. Par ailleurs, leur rentabilité est plus élevée pour l’un, plutôt
plus élevée pour le deuxième et plutôt plus faible pour le dernier. Deux voies ont été empruntées pour
obtenir ces résultats positifs sur les herbicides et la rentabilité : soit une diversification moyenne de la
succession Maïs-Blé combinée à un travail du sol intensif, soit peu de travail du sol associé à une
couverture du sol et combinés à une diversification importante de la succession. La maîtrise des
adventices qui en résulte est plus ou moins satisfaisante selon les systèmes de culture. L’analyse
agronomique des réussites et des échecs de la maîtrise des adventices permet de tirer des
enseignements sur les conditions de réussite de chacune des stratégies.Three innovative cropping systems were tested during several years. They aimed to reduce the use of
pesticides by 50% compared to local reference cropping systems while being still profitable. Reference [br/]
systems were maize-winter wheat rotations in mixed crop-livestock agricultural systems. The use of total
pesticides was reduced by 22-50%, i.e. 12-65% for herbicides and 55-80% for other pesticides. Toxic
exposure of farmers was lower for innovative systems ; risk of active substance transfer to the
environment was also lower. Regarding profitability, results were different from one experiment to
another, with higher economic margins for the innovative system for two of them, and lower margin for
the last one. Two strategies were employed to achieve these positive results on pesticides use and
impacts and on profitability : moderate diversification of crop sequences combined with intensive tillage
on one hand versus minimum tillage associated with soil cover and high crop sequences diversification
on the other hand. Resulting weed pressure was acceptable or rather acceptable in two out of the three
experiments. Agronomic analysis of success and failure cases led to new insights on success conditions
for both strategies of weed management
Plant DNA Polymerases
No full textMaintenance of genome integrity is a key process in all organisms. DNA polymerases (Pols) are central players in this process as they are in charge of the faithful reproduction of the genetic information, as well as of DNA repair. Interestingly, all eukaryotes possess a large repertoire of polymerases. Three protein complexes, DNA Pol alpha, delta, and epsilon, are in charge of nuclear DNA replication. These enzymes have the fidelity and processivity required to replicate long DNA sequences, but DNA lesions can block their progression. Consequently, eukaryotic genomes also encode a variable number of specialized polymerases (between five and 16 depending on the organism) that are involved in the replication of damaged DNA, DNA repair, and organellar DNA replication. This diversity of enzymes likely stems from their ability to bypass specific types of lesions. In the past 10-15 years, our knowledge regarding plant DNA polymerases dramatically increased. In this review, we discuss these recent findings and compare acquired knowledge in plants to data obtained in other eukaryotes. We also discuss the emerging links between genome and epigenome replication
Opening data and research objects in viticulture: The Viticulture Data Journal (VDJ)
No full textThe Viticulture Data Journal (VDJ) is launched with the aim of offering a publication venue for non-conventional but valuable outputs of the research cycle: data, models, methods, software, data analytics pipelines and visualisation methods in viticultural research. VDJ is published on the ARPHA journal platform, which supports the full life cycle of a manuscript, from writing through submission, peer review, publication and dissemination within a single online collaborative platform. During the AGINFRA+ project, which has supported the journal launch, ARPHA has been extended to be used from the AGINFRA+ Virtual Research Environment (VRE