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The response of crops to changing climate and atmospheric CO2 concentration ([CO2]) could have large effects on food production, and impact carbon, water, and energy fluxes, causing feedbacks to the climate. To simulate the response of temperate crops to changing climate and [CO2], which accounts for the specific phenology of crops mediated by management practice, we describe here the development of a process-oriented terrestrial biogeochemical model named ORCHIDEE-CROP (v0), which integrates a generic crop phenology and harvest module, and a very simple parameterization of nitrogen fertilization, into the land surface model (LSM) ORCHIDEEv196, in order to simulate biophysical and biochemical interactions in croplands, as well as plant productivity and harvested yield. The model is applicable for a range of temperate crops, but is tested here using maize and winter wheat, with the phenological parameterizations of two European varieties originating from the STICS agronomical model. We evaluate the ORCHIDEE-CROP (v0) model against eddy covariance and biometric measurements at seven winter wheat and maize sites in Europe. The specific ecosystem variables used in the evaluation are CO2 fluxes (net ecosystem exchange, NEE), latent heat, and sensible heat fluxes. Additional measurements of leaf area index (LAI) and aboveground biomass and yield are used as well. Evaluation results revealed that ORCHIDEE-CROP (v0) reproduced the observed timing of crop development stages and the amplitude of the LAI changes. This is in contrast to ORCHIDEEv196 where, by default, crops have the same phenology as grass. A halving of the root mean square error for LAI from 2.38 ± 0.77 to 1.08 ± 0.34 m2 m−2 was obtained when ORCHIDEEv196 and ORCHIDEE-CROP (v0) were compared across the seven study sites. Improved crop phenology and carbon allocation led to a good match between modeled and observed aboveground biomass (with a normalized root mean squared error (NRMSE) of 11.0–54.2 %), crop yield, daily carbon and energy fluxes (with a NRMSE of  ∼  9.0–20.1 and  ∼  9.4–22.3 % for NEE), and sensible and latent heat fluxes. The simulated yields for winter wheat and maize from ORCHIDEE-CROP (v0) showed a good match with the simulated results from STICS for three sites with available crop yield observations, where the average NRMSE was  ∼  8.8 %. The model data misfit for energy fluxes were within the uncertainties of the measurements, which themselves showed an incomplete energy balance closure within the range 80.6–86.3 %. The remaining discrepancies between the modeled and observed LAI and other variables at specific sites were partly attributable to unrealistic representations of management events by the model. ORCHIDEE-CROP (v0) has the ability to capture the spatial gradients of carbon and energy-related variables, such as gross primary productivity, NEE, and sensible and latent heat fluxes across the sites in Europe, which is an important requirement for future spatially explicit simulations. Further improvement of the model, with an explicit parameterization of nutritional dynamics and management, is expected to improve its predictive ability to simulate croplands in an Earth system model.

We address the problem of the high-frequency correction of water vapour fluxes measured by eddy covariance with a closed-path infrared gas analyser (IRGA). Different transfer functions are compared and evaluated at a forested (Vielsalm, Belgium) and an agricultural (Lonzée, Belgium) site. Classical functions, usually applied to correct CO₂ fluxes (Gaussian, Lorentzian), are found to be unsuited to water vapour cospectral corrections, being characterised by too sharp a decrease at high frequency. Two other functions characterised by a lower decreasing slope are found to better fit experimental transfer functions. They were calibrated and validated on experimental transfer functions and their dependency on air humidity is parameterised. On this basis, new correction coefficients are estimated. The coefficients are found to be larger than those based on the classical functions, even when the dependency of the latter on air humidity is taken into account. The difference amounts to 10% at the forested site and to 5% larger at the crop site. The study highlights the necessity of characterising the water transfer function shape and taking it into account in the correction factor at each site equipped with a closed path IRGA.

Both laboratory and field experiments were carried out in order to define suitable configuration ranges for the gas sampling systems (GSSs) of infrared gas analyzers (IRGAs) used in eddy covariance measurements. In the laboratory, an original dynamic calibration bench was developed in order to test the frequency attenuation and pressure drop generated by filters. In the field, three IRGAs of the same type equipped with different filters or different rain caps were installed and run and the real frequency response of the complete setup was tested. The main results are as follows. – Filters may have a strong impact on the pressure drop in the GSS and this impact increases with flow rate. – Conversely, no impact of the tested filters on cutoff frequency was found, GSSs with and without filters presenting similar cutoff frequencies. – The main limiting factor of cutoff frequency in the field was found to be the rain cap design. In addition, the impact of this design on pressure drop was also found to be noteworthy.

Maintaining reproduction in highly variable, often stressful, environments is an essential challenge for all organisms. Even transient exposure to mild environmental stress may directly damage germ cells or simply tax the physiology of an individual, making it difficult to produce quality gametes. In Caenorhabditis elegans , a large fraction of germ cells acts as nurse cells, supporting developing oocytes before eventually undergoing so-called physiological germ cell apoptosis. Although C . elegans apoptosis has been extensively studied, little is known about how germline apoptosis is influenced by ecologically relevant environmental stress. Moreover, it remains unclear to what extent germline apoptosis contributes to maintaining oocyte quality, and thus offspring viability, in such conditions. Here we show that exposure to diverse environmental stressors, likely occurring in the natural C . elegans habitat (starvation, ethanol, acid, and mild oxidative stress), increases germline apoptosis, consistent with previous reports on stress-induced apoptosis. Using loss-of-function mutant alleles of ced-3 and ced-4 , we demonstrate that eliminating the core apoptotic machinery strongly reduces embryonic survival when mothers are exposed to such environmental stressors during early adult life. In contrast, mutations in ced-9 and egl-1 that primarily block apoptosis in the soma but not in the germline, did not exhibit such reduced embryonic survival under environmental stress. Therefore, C . elegans germ cell apoptosis plays an essential role in maintaining offspring fitness in adverse environments. Finally, we show that ced-3 and ced-4 mutants exhibit concomitant decreases in embryo size and changes in embryo shape when mothers are exposed to environmental stress. These observations may indicate inadequate oocyte provisioning due to the absence of germ cell apoptosis. Taken together, our results show that the central genes of the apoptosis pathway play a key role in maintaining gamete quality, and thus offspring fitness, under ecologically relevant environmental conditions.

The subjoined extract from a French work on angling, lately published in Paris, will, it is presumed, furnish some additional information in regard to the properties and peculiarities of a species of fish, about which, considering the rank they hold in the estimation of the angler and the epicure, it is singular that so little should be known. As the above mentioned publication is held in high repute among the French, and has not, I believe, been translated, I have taken the liberty of sending you the annexed translation, and hope it may be found an acceptable offering to the readers of the first periodical exclusively devoted to rural amusements and manly sports which has yet appeared on this side of the Atlantic.

Anaerobic digestion (AD) has recently been studied to obtain products of greater interest than biogas, such as volatile fatty acids (VFAs) and phytoregulators. The effect of the initial pH of cow manure and the fermentation time of the AD on the microbial composition, VFAs, indole-3-acetic acid (IAA) and gibberellic acid (GA3) production was evaluated. The cow manure (7% solids) was adjusted to initial pH values of 5.5, 6.5, 7.5, and 8.5, and the AD products were analyzed every four days until day 20. The initial pH and the fermentation time had an important effect on the production of metabolites. During AD, only the hydrolytic and acidogenic stages were identified, and the bacteria found were from the phyla Firmicutes, Bacteroidetes, Actinobacteria, and Spirochaetes. The most abundant genera produced in the four AD were Caproiciproducens, Clostridium sensu stricto 1, Romboutsia, Paeniclostridium, Turicibacter, Peptostreptococcaceae, Ruminococcaceae and Fonticella. The highest amount of VFAs was obtained at pH 8.5, and the production of the acids was butyric > acetic > propionic. The maximum production of GA3 and IAA was at an initial pH of 6.5 on day 20 and a pH of 5.5 on day 4, respectively. There was a strong correlation (> 0.8) between the most abundant microorganisms and the production of VFAs and GA3. The anaerobic digestion of cow manure is a good alternative for the production of VFAs, GA3 and IAA.

The banana gene MaWRKY45 gene encodes a WRKY transcription factor (TF) that is closely related to OsWRKY45, which is a master regulator of defense responses in rice. MaWRKY45 is a transcription factor with proven transactivation activity and nuclear localization. Its expression is upregulated by the defense phytohormones salicylic acid (SA) and jasmonic acid (JA). Despite these findings, its transcriptome-wide impact during overexpression remains unexplored. Accordingly, the present study employed the Infiltration-RNAseq method to identify differentially expressed genes (DEGs) resulting from the overexpression of MaWRKY45 in the leaves of the model plant Nicotiana benthamiana. A total of 2473 DEGs were identified in N. benthamiana leaves overexpressing the banana gene MaWRKY45. Of these, 1092 were up-regulated and 1381 were down-regulated. Among the genes that were found to be up-regulated, those encoding proteins that are involved in plant immunity were identified. These included disease resistance receptors, proteins that are involved in cell wall reinforcement, proteins that possess antimicrobial and insecticidal activities, and defense-related TFs. It was thus concluded that the function of the banana gene MaWRKY45 is associated with the plant immune system, and that its overexpression can lead to enhance defense responses.

The resistance of wood against fungal decay, in short the natural durability, is one of the main criteria for defining the potential use of a wood species. Wood collections, or xylaria, offer the unique opportunity to screen many specimens and species for the latter purpose yet sample size is often limited and standardized tests are often not possible neither desired given the historical and cultural value of these specimens. Two different methods to determine the natural durability are tested and presented here, more specifically the mini-block test and chemical fingerprinting by Direct Analysis in Real-Time Time-Of-Flight Mass Spectrometry (DART TOFMS). Fungal decay by Trametes versicolor was determined for 577 mini-blocks collected from xylarium specimens and 602 mini-blocks from commercial species, not belonging to the xylarium collection, were included as a benchmark. Mass loss percentages of the different species are similar to reported values, supporting the use of the mini-block test when standardized testing is hardly feasible. Furthermore, as expected there is also a significantly negative relationship between density and the mass loss percentages from the mini-block test ( r -Spearman = − 0.65***). Finally, partial least square-based prediction of recorded mass loss by using the DART TOFMS chemical fingerprints is promising ( R 2 -adjusted = 0.40***), yet the accuracy differs between species.

Moisture performance is an important factor determining the resistance of wood-based building materials against fungal decay. Understanding how material porosity and chemistry affect moisture performance is necessary for their efficient use, as well as for product optimisation. In this study, three complementary techniques (X-ray computed tomography, infrared and low-field NMR spectroscopy) are applied to elucidate the influence of additives, manufacturing process and material structure on the liquid water absorption and desorption behaviour of a selection of wood-based panels, thermally modified wood and wood fibre insulation materials. Hydrophobic properties achieved by thermal treatment or hydrophobic additives such as paraffin and bitumen, had a major influence on water absorption and desorption rates. When hydrophobic additives did not play a role, pore distributions and manufacturing process had a decisive influence on the amount and rate of absorption and desorption. In that case, a higher porosity resulted in a higher water absorption rate. Our results show that there is a clear potential for tailoring materials towards specific moisture performance by better understanding the influence of different material characteristics. This is useful both for achieving desired moisture buffering as well as to increase service life of wood-based materials. From a sustainability perspective, fit-for-purpose moisture performance is often easier to achieve and preferred than wood protection by biocide preservative treatments.

One open question regarding plant–microbe interactions is how a plant interacts molecularly with both a beneficial microbe and a pathogenic fungus. This study used RNA-seq to investigate molecular responses in maize roots during a tripartite interaction with the fungal pathogen Fusarium verticillioides (Fv), which causes stalk, ear, and root rot, and the endophytic biocontrol agent Bacillus cereus sensu lato B25, known to suppress Fv and promote plant growth. Roots of seven-day-old maize inoculated with Fv (Zm-Fv), B25 (Zm-B25), and co-inoculated (Zm-Fv-B25) were compared to uninoculated control (Zm). Differential Gene Expression (DEG), Gene Ontology (GO) and KEGG analysis revealed distinct molecular responses. Fv suppressed plant pathways related to DNA and protein synthesis and impaired root development. In contrast, B25 triggered defense priming and growth-related responses. In the co-inoculation experiment (Zm-B25-Fv), upregulated DEGs were associated with both defense-related metabolic pathways, including jasmonic acid signaling and secondary metabolite biosynthesis, and genes involved in plant growth processes. Co-expression networks using Arabidopsis orthologs supported the induction of defense- and growth and development-related genes. This study is the first RNA-seq analysis of maize root molecular responses during the tripartite interaction with a fungal pathogen and its bacterial biocontrol agent, providing new directions for further research to understand the detailed molecular mechanisms underlying this interaction fully.