Early prediction of <em>Miscanthus</em> biomass production and composition based on the first six years of cultivation

International audienceMiscanthus is a promising feedstock for second-generation bioethanol production. This perennial crop produces its biomass in two phases: a yield-building phase, where the biomass production increases gradually, and a plateau phase, where it is maintained. However, to target the breeding of Miscanthus for second-generation bioethanol production, the early selection of interesting traits is critical. We therefore investigated the interannual correlations within and among the traits related to biomass production and composition. We studied 21 clones belonging to M. x giganteus J. M. Greef & Deuter ex Hodk. & Renvoize, M. sacchariflorus (Maxim.) Benth. & Hook. f. ex Franch., and M. sinensis Andersson species cultivated on plots from the second to the sixth year at two harvest dates. The biomass production, canopy height, plant stem number, and above-ground plant volume index were better predicted from the third year than from the second year (minimum correlation coefficients of 0.76 and 0.67 respectively). The stem diameter was well predicted from the second year (correlations above 0.93). The canopy height and the above-ground plant volume index determined in the second and third year were the best predictors of the biomass produced in the second, third, and fourth year (minimum correlations of 0.77 against 0.52 for flowering date or 0.64 for stem diameter). For older crops, the canopy height measured in the second and third year was the best predictor of the biomass production (correlations above 0.70). The interannual correlations were lower for the biomass composition-related traits than for the production-related traits and fluctuated over time. These results showed that early prediction of interesting traits is feasible to breed varieties tailored for biofuel production

Miscanthus clones for cellulosic bioethanol production: Relationships between biomass production, biomass production components, and biomass chemical composition

International audienceThe perennial miscanthus crop is a promising feedstock for cellulosic ethanol production due to its high yield, low input and low environmental impacts. To be suitable for cellulosic ethanol production, cultivated Miscanthus clones need to present not only high aboveground biomass production, but also high cellulose and hemicellulose contents and low lignin, soluble, and ash contents. By testing M: x giganteus, M. sacchariflorus, and M. sinensis clones, we investigated the relationships between biomass production and biomass composition traits at two harvest dates over 3 years. High aboveground biomass production was associated with high canopy height, high stem diameter, late flowering, and high cellulose and lignin contents but low hemicellulose, soluble, and ash contents. The aboveground biomass production was positively correlated with the potential yields of cellulose, hemicelluloses, and lignins. These relationships were consistent throughout the years and the harvest dates. The most productive Miscanthus clones displayed high cellulose contents and low soluble and ash contents; however, they displayed low hemicellulose contents and high lignin contents. The total aboveground biomass composition was closer to the stem composition than to the leaf composition. Nevertheless, the leaves were interesting because of their high hemicellulose and low lignin contents. Lastly, all of the studied factors were significant, but the biomass production traits were mainly affected by the year of cultivation or clone, while the biomass composition traits were mainly affected by the harvest date. All of the traits showed low interaction effects. These results will guide the breeding of Miscanthus clones that are tailored for biofuel production

Shoot organogenesis in three Miscanthus species and evaluation for genetic uniformity using AFLP analysis

International audienceA simple, efficient protocol for direct in vitro shoot organogenesis and regeneration was established for three species of Miscanthus including two clones of Miscanthus x giganteus, one clone of M. sinensis and one clone of M. sacchariflorus. Shoots were induced from the axillary nodes of both M. x giganteus and M. sacchariflorus and from apical meristems of both M. sinensis and M. sacchariflorus. A tillering method was used to accelerate shoot proliferation. Shoots were rooted in a wet perlite substrate in pots in the greenhouse. Subsequently, rooted plants were transferred to the field. The genetic uniformity of regenerated plants was evaluated using amplified fragment length polymorphism analysis and compared to that of rhizome-propagated plants. A total of 33,443 fragments were generated, representing 869 markers. There were 21 fragments (0.06 % of the fragments) or 19 markers (2.19 % of the markers) that were polymorphic, and almost all of these were singletons. The three species showed similar polymorphisms. Genetic variability was also found in the rhizome-propagated plants, sometimes at a higher rate than in the in vitro culture, indicating that the genetic uniformity was not altered by the protocol. This protocol may help breeders produce new clones of Miscanthus in the future

Rhizome filling seems to be triggered by climatic events in Miscanthus x giganteus

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Safety and Efficacy of Immune Checkpoint Inhibitors in Patients with Cancer and Preexisting Autoimmune Disease: A Nationwide Multicenter Cohort Study

International audienceImmune Checkpoint Inhibitors (ICI) for cancer therapy induce frequent Immune Related Adverse Effects (IRAE). Therefore, most patients with Preexisting Autoimmune Diseases (PAD) have been excluded from clinical trials. This study aims to evaluate the safety and efficacy of ICI in patients with PAD and cancer