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The effect of different levels of shading in a photovoltaic greenhouse with a North–South orientation
No full textPhotovoltaic greenhouses have been claimed to be a solution to cover the energy demand of the protected crops sector. Thus, there is a need to know what is the maximum percentage of shading produced by roof-top photovoltaic panels that does not affect crop yields. The present study analyzes the effects of increasing percentages of shading in a greenhouse tomato crop located in the southeast of Spain. For this study, photovoltaic panels have been simulated with opaque sheets located in the roof-top of a north–south oriented greenhouse. Three treatments of top roof shading percentage (15%, 30% and 50%) where studied and compared with the control treatment without shading (0%). During the study, parameters registered were radiation, temperature, pH and electric conductivity of the substrate, crop yields and fruit quality. Results of the analysis show that higher percentages of shading in the roof-top of greenhouses reduce so much available radiation for the crop causing a reduction in the yield and fruit quality, even in Mediterranean areas where radiation is not a limiting factor
Methods assessment of self-tanning of rapeseed and sunflower meal fractions enriched in proteins and phenolic compounds using in vitro measurement of protein rumen degradability
No full textTwo protein tanning methods were evaluated to contribute to the withdrawal of formaldehyde as a tanning agent of meals for feeding ruminants. The experimental materials were two fractions of rapeseed and sunflower meals collected at the positive electrode of an electrostatic separator, presenting high contents in proteins and phenolic compounds. The objective was to make phenolics and proteins interact without addition of exogenous tannins. Treatment CH incubated a meal fraction:water mixture (1:2, w:w) for 48 h at 50 degrees C. Treatment FR incubated a meal fraction:water mixture (1:10, w:w) at pH 9.0 for 48 h at 4 degrees C. Microbial proteolysis on meal fractions were quantified during 24 h rumen batch fermentations with cellulose and starch as nitrogen-free energy sources. The net production of ammonia tended to be reduced by treatment FR mostly on rapeseed, corresponding to an 8% saving of rapeseed meal proteins degradable in the rumen. When untreated, the sunflower fraction decreased methane production by 50%, while treatments restored the fermentation pattern. Cold alkaline treatment could be considered to protect meal proteins from degradation by rumen micro-organisms.Deux méthodes de tannage des protéines ont été évaluées pour contribuer au remplacement du formaldéhyde comme agent tannant des tourteaux destinés à l’alimentation des ruminants. Les matériaux expérimentaux étaient deux fractions de tourteaux de colza et tournesol collectées à l’électrode positive d’un séparateur électrostatique, présentant des teneurs élevées en protéines et en composés phénoliques. Le but était de faire interagir les composés phénoliques et les protéines sans addition de tanins exogènes. Le traitement CH a consisté à incuber un mélange tourteau/eau (1/2, poids/poids) pendant 48 h à 50 °C. Le traitement FR a consisté à incuber un mélange tourteau/eau (1/10, poids/poids) à pH 9,0 pendant 48 h à 4 °C. La protéolyse des fractions de tourteau par les microbes du rumen a été quantifiée lors de fermentations in vitro de 24 h avec de la cellulose et de l’amidon comme sources d’énergie sans azote. Le traitement FR a eu tendance à réduire la production nette d’ammoniac, principalement avec le colza, équivalant à la protection de 8 % des protéines de tourteau de colza dégradables dans le rumen. La fraction de tournesol non traitée a diminué la production de méthane de 50 %, cependant les traitements ont restauré le profil fermentaire. Le traitement alcalin à froid pourrait être envisagé afin de protéger les protéines du tourteau de la dégradation par les micro-organismes du rume
Comparative transcriptomics enables the identification of functional orthologous genes involved in early leaf growth.
No full textLeaf growth is a complex trait for which many similarities exist in different plant species, suggesting functional conservation of the underlying pathways. However, a global view of orthologous genes involved in leaf growth showing conserved expression in dicots and monocots is currently missing. Here we present a genome-wide comparative transcriptomics analysis between Arabidopsis and maize, identifying conserved biological processes and gene functions active during leaf growth. Despite the orthology complexity between these distantly related plants, 926 orthologous gene groups including 2,829 Arabidopsis and 2,974 maize genes with similar expression during leaf growth were found, indicating conservation of the underlying molecular networks. We found 65% of these genes involved in one-to-one orthology, whereas only 28.7% of the groups with divergent expression had one-to-one orthology. Within the pool of genes with conserved expression, 19 transcription factor families were identified, demonstrating expression conservation of regulators active during leaf growth. Additionally, 25 Arabidopsis and 25 maize putative targets of the TCP TFs with conserved expression were determined based on the presence of enriched transcription factor binding sites. Based on large-scale phenotypic data, we observed that genes with conserved expression have a higher probability to be involved in leaf growth and that leaf-related phenotypes are more frequently present for genes having orthologs between dicots and monocots than clade-specific genes. This study shows the power of integrating transcriptomics with orthology data to identify or select candidates for functional studies during leaf development in flowering plants
Post- moderate intensity exercise energy replacement does not reduce subsequent appetite and energy intake in adolescents with obesity
No full textExercise modifies energy intake in adolescents with obesity, but whether this is mediated by the exercise-induced energy deficit remains unknown. The present study examined the effect of exercise with and without dietary replacement of the exercise energy expenditure on appetite, energy intake and food reward in adolescents with obesity. Fourteen 12-15 years adolescents with obesity (8girls; Tanner3-4; BMI 34.8+/-5.7kg/m2; BMI-z score 2.3+/-0.4) randomly completed 3 experimental conditions: i) rest control (CON); ii) 30-min cycling (EX); iii) 30-min cycling with dietary energy replacement (EX+R). Ad libitum energy intake (EI) was assessed at lunch and dinner, and food reward (Leeds Food Preference Questionnaire) before and after lunch. Appetite was assessed at regular intervals. Lunch, evening and total EI (excluding the post-exercise snack in EX-R) were similar across conditions. Lunch and total EI including the post-exercise snack in EX+R were higher in EX-R than CON and EX; EX and CON were similar. Total relative EI was lower in EX (1502+/-488 kcal) compared with CON (1713+/-530; p/=0.10). Pre-meal explicit liking for fat was lower in EX compared to CON and EX+R (p=0.05). There was time by condition interaction between EX and CON for explicit wanting and liking for fat (p=0.01). Despite similar appetite and energy intake, adolescents with obesity do not adapt their post-exercise food intake to account for immediate dietary replacement of the exercise-induced energy deficit, favoring a short-term positive energy balance
Knockout of VvCCD8 gene in grapevine affects shoot branching
No full textBackground Shoot branching is an important trait of plants that allows them to adapt to environment changes. Strigolactones (SLs) are newly identified plant hormones that inhibit shoot branching in plants. The SL biosynthesis genes CCD7 (carotenoid cleavage dioxygenase 7) and CCD8 have been found to regulate branching in several herbaceous plants by taking advantage of their loss-of-function mutants. However, the role for CCD7 and CCD8 in shoot branching control in grapevine is still unknown due to the lack of corresponding mutants. Results Here we employed the CRISPR/Cas9 system to edit the VvCCD7 and VvCCD8 genes in the grape hybrid 41B. The 41B embryogenic cells can easily be transformed and used for regeneration of the corresponding transformed plants. Sequencing analysis revealed that gene editing has been used successfully to target both VvCCD genes in 41B embryogenic cells. After regeneration, six 41B plantlets were identified as transgenic plants carrying the CCD8-sgRNA expression cassette. Among these, four plants showed mutation in the target region and were selected as ccd8 mutants. These ccd8 mutants showed increased shoot branching compared to the corresponding wild-type plants. In addition, no off-target mutation was detected in the tested mutants at predicted off-target sites. Conclusions Our results underline the key role of VvCCD8 in the control of grapevine shoot branching
A DSS tool (software) integrating the models developed in Tasks 3.1 to 3.4 for different livestock species and categories
No full textColEval: Honeybee COLony Structure EVALuation for Field Surveys
No full textMethods for the evaluation and comparison of the structure of numerous honeybee colonies are needed for the development of applied and fundamental field research, as well as to evaluate how the structure and activity of honeybee colonies evolve over time. ColEval complements existing methods, as it uses an online reference image bank for (human) learning and training purposes. ColEval is based on the evaluation of the surface area percentage occupied by different components of a honeybee colony: adult worker bees, open and capped brood, honey, nectar, and pollen. This method is an essential tool for the description of the evolution in the size of honeybee colonies. The procedure makes allowances for tendencies between different observers and uses them to calculate accurate
measurements of honeybee colony evaluation. ColEval thus allows for a posteriori comparison of under- or over-evaluation made by different observers working on the same project; it is thus possible to eliminate observer bias in the measurements and to conduct large surveys
Grassland management for sustainable agroecosystems
No full textKnowledge on sustainable grassland management is available in the large body of literature. However, it is unclear where to look for it, and what is really relevant to the many interrelated challenges of sustainable grassland management. This special issue illustrates options to fill some of those gaps. This editorial introduces the Special Issue entitled "Grassland Management for Sustainable Agroecosystems". Two review articles deal with (i) concepts for monitoring grassland degradation (by Tiscornia et al. Agronomy 2019, 9, 239) and (ii) impacts of alternative management practices and disturbances (by Wagle and Gowda et al. Agronomy 2018, 8, 300). One paper (by Steiner et al. Agronomy2019, 9, 699). summarized a series of papers of the special issue. Other topics covered include four main aspects: (I) Landscape features (Ravetto Enri et al. Agronomy 2019, 9, 333), two papers by Northup et al. Agronomy 2019, 9, 329, Northup et al. Agronomy 2019, 9, 281, and Ma et al. Agronomy 2019, 9, 238; (II) climate (Zhou et al. Agronomy 2019, 9, 219, Starks et al. Agronomy 2019, 9,235, and Moinet et al. Agronomy 2019, 9, 124); (III) soil fertility (Franzluebbers et al. Agronomy 2019, 9, 204, Poblete-Grant et al. Agronomy 2019, 9, 191); and (IV) one on modeling (Puche et al. Agronomy 2019, 9, 183). Two additional papers are from Andueza et al. Agronomy 2019, 9, 273 (on the feed value of barn-dried hay) and ubeda et al. Agronomy 2019, 9, 340 (on the role of prescribed burns)
MS-based targeted metabolomics of eicosanoids and other oxylipins: Analytical variability and interlaboratory comparison of esterified oxylipin profile
No full textIntroduction
Oxylipins are potent lipid mediators involved in numerous physiological and pathological processes
and their quantitative profiling has gained a lot of attention [1]. To maximize the utility of the
oxylipin profiling in clinical research it is now crucial (i) to assess its analytical variability; (ii) to
determine its comparability between laboratories and (iii) to identify putative critical oxylipins. These
three main challenges are addressed within the EU JPI HDHL*-Oxygenate project.
Technological and methodological innovation
To address the challenges stated above, a SOP was established by a reference laboratory for the MSbased
targeted metabolomics of total oxylipins (free + esterified, ~160 oxylipins) in human plasma
[2]. The intra- and inter-day variabilities of each oxylipin were assessed. Then, the SOP was
transferred to 4 independent laboratories together with mixtures of internal standards, calibrants
and 7 different pools of plasma to determine the comparability of oxylipin profiles between labs.
Results and impact
The cumulated intra-/inter-day variabilities revealed that 68 % of oxylipins (>LLOQ) have a CV<20%.
The interlab-variability was low and dependent on the type of plasma analyzed. Overall, our results
show that the MS-based profiling of total oxylipins in human plasma is a robust tool for clinical
research. Moreover, the comparability of oxylipin profiles will allow generating large-scale databases
allowing a better understanding of the relationships between oxylipins and human health.
References
[1] Gladine C. et al. 2019. Free Radical Biology and Medicine 144 (2019) 72–89
[2] Ostermann et al. 2019. Prostag Oth Lipid M. DOI: 10.1016/j.prostaglandins.2019.106384
*Joint Programming Initiative “A healthy diet for a healthy life