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Concurrent effect of nanomaterials (NMs) and warming on plant performance remains largely unexplored. In this study, the effects of nanopesticide CuO and nanofertilizer CeO2 on wheat (Triticum aestivum) under optimal (22 °C) and suboptimal (30 °C) temperatures were evaluated. CuO-NPs exerted a stronger negative effect on plant root systems than CeO2-NPs at tested exposure levels. The toxicity of both NMs could be attributed to altered nutrient uptake, induced membrane damage, and raised disturbance of antioxidative related biological pathways. Warming significantly inhibited root growth, which was mainly linked to the disturbance of energy metabolism relevant biological pathways. The toxicity of NMs was enhanced upon warming, with a stronger inhibition of root growth and Fe and Mn uptake. Increasing temperature increased the accumulation of Ce upon CeO2-NP exposure, while the accumulation of Cu was not affected. The relative contribution of NMs and warming to their combined effects was evaluated by comparing disturbed biological pathways under single and multiple stressors. CuO-NPs was the dominant factor inducing toxic effects, while both CeO2-NPs and warming contributed to the mixed effect. Our study revealed the importance of carefully considering global warming as a factor in risk assessment of agricultural applications of NMs.

Sophus Lie (1842-1899) known as the founder of the theory of transformation groups, originally aimed to study solutions of differential equations via their symmetries. Over the decades this theory has evolved into the theory of Lie groups. These Lie groups are of an analytic and geometric nature, but Sophus Lie's principal discovery was that these groups can be studied by their "infinitessimal generators" leading to a linearization of the group. The group structure endows this linearized space with a special bracket operation, [x,y]=xy-yx, which gives rise to Lie algebras. The main applications for Lie algebras stem from physics, notably in quantum mechanics and particle physics. It turns out that representations of Lie algebras are the way to describe symmetries of physical systems. So, it becomes an important task to figure out what all the possible representations are. Thus, our main goal for this thesis is to classify all finite-dimensional semisimple Lie algebra representations., Applied Mathematics

Mangroves can provide coastal protection by attenuating waves, currents, and trapping sediment (Menéndez et al., 2020; Bao, 2011). The effect of mangroves on the hydrodynamics depends on their size, location, density, distribution and morphology of the vegetation (Mendez and Losada, 2004). Mangrove loss during storm events will therefore impact the coastal protection. The soil-root interaction and influences of soil properties in the resistance of a mangrove tree against failure is neglected in most studies of flood protection by mangroves, due to a lack in understading. This thesis improves the understanding of the soil-root interaction by deriving the schematization for multiple failure mechanisms in comparison with field observations. Firstly, the wind and wave forces are modelled to determine the different loads in the forest. Secondly, a novel schematization was developed of different failure mechanisms considering the soil properties and root system. All results are developed for a case study of a fringe forest in Demak, existing of Avicennia marina rooted in a silty, saturated soil. To be able to determine the difference between the seaward and landward edge of the forest, the width of the forest is increased to 500 meter. Also, due to a lack of information on the mechanical strength of Avicennia m., the mechanical properties of Rhizophora m. are used, which will overestimate the resistance due to the higher wood density of Rhizophora m. (Manguriu et al., 2013). The results show that the drag forces were largely influenced by the tree architecture (such as vegetation width and height), forest density and inundation of the tree. Larger wind and wave forces, and therefore a larger moment occured if the width of the vegetation increased. If the height of the tree increases, a smaller part of the canopy is submerged. This leads to a decreased area that is exposed to waves and therefore a declined wave force. A higher tree does enlarge the area, Double degree in Civil Engineering | Hydraulic Engineering | Hydraulic Structures and Flood Risk and Geo-Engineering, Civil Engineering | Hydraulic Engineering | Hydraulic Structures and Flood Risk, Geo-Engineering

The extraction efficiency, recovery, quantification, and stability of isoflavones (daidzein, genistein and puerarin) from the wastes /by-products of kudzu roots and soy molasses were evaluated by using natural deep eutectic solvents (NADESs) coupled with ultrasound-assisted extraction. The NADES extraction was compared with the conventional Soxhlet extraction technique, and the extracted isoflavones were quantified using HPLC-UV/Vis. Results showed extractability of puerarin to be significantly increased (p < 0.0001) in proportion to the increased water concentration of NADES (9.7 ± 0.2, 12.6 ± 0.2, and 14.8 ± 0.3 mg/g in NADESs containing 10%, 20%, and 30% water, respectively). Despite having less isoflavone content, kudzu roots and soy molasses extracts obtained using NADES exhibited higher antioxidant activity when compared with methanolic extracts. Further, NADES extracts also markedly reduced the degradation degree of isoflavones. The results of this investigation support the use of green extraction techniques to obtain value-added components like isoflavones from wastes/by-products like that of kudzu roots and soy molasses, which are envisaged to find future potential applications in the food and pharmaceutical industries. © 2022 Elsevier B.V.

Myrothamnus flabellifolia is the only woody resurrection plant discovered so far and could recover from extreme desiccation condition. However, few genes related to its strong drought tolerance have been characterized, and the underlying molecular mechanisms remains mysterious. Members of WRKY transcription factor family are effective in regulating abiotic stress responses or tolerance in various plants. An early dehydration-induced gene encoding a WRKY transcription factor namely MfWRKY41 was isolated from M. flabellifolia, which is homologous to AtWRKY41 of Arabidopsis. It contains a typical WRKY domain and zinc finger motif, and is located in the nucleus. Comparing to wild type, the four transgenic lines overexpressing MfWRKY41 showed better growth performance under drought and salt treatments, and exhibited higher chlorophyll content, lower water loss rate and stomatal aperture and better osmotic adjustment capacity. These results indicated that MfWRKY41 of M. flabellifolia positively regulates drought as well as salinity responses. Interestingly, the root system architecture, including lateral root number and primary root length, of the transgenic lines was enhanced by MfWRKY41 under both normal and stressful conditions, and the antioxidation ability was also significantly improved. Therefore, MfWRKY41 may have potential application values in genetic improvement of plant tolerance to drought and salinity stresses. The molecular mechanism involving in the regulatory roles of MfWRKY41 is worthy being explored in the future.

Climate change is an ongoing issue in various fields, including forestry. More frequent and severe droughts have been already noted around the world, also in Europe. Visible reduction in available water in forests has adverse consequences such as increased tree mortality, higher vulnerability and smaller growth. Appropriate silviculture treatment can improve forest conditions. Proper thinning practices can reduce belowground competition for water. In the current study, water with a detectable isotope (deuterium, 2H) was applied in Scots pine stands with different intensities of thinning in order to investigate water route and horizontal root systems structure. Based on the amount of the label in the sapwood cores of trees, water uptake was examined. In addition the sapwood area of each analysed tree was calculated. Knowing the exact location of trees, the water route on the plot was mapped. The results showed a strong correlation between the place of water application and the distance of a tree. Belowground roots overlap was proven and reached 3,5 trees /m2. In heavily thinned plots labelled trees uptook the biggest amount of 2H. There was no correlation between the sapwood area of a tree and the amount of uptaken label. Visual presentation of trees distribution showed belowground avoidance of competition – root systems are not developed uniformly around tree stem. Although there are some limitations of this study such as the short time between thinning and experiment establishment, the results obtained gave a valuable insight into the root system and connected with other research, including examination of root development after thinning in a few years, can be helpful and useful in adjusting thinning practice in face of lack of water in the forest.

Licorice (Glycyrrhiza uralensis Fisch.) is a salt and drought tolerant legume suitable for rehabilitating abandoned saline lands, especially in dry arid regions. We hypothesized that soil amended with maize-derived biochar might alleviate salt stress in licorice by improving its growth, nutrient acquisition, and root system adaptation. Experiments were designed to determine the effect of different biochar concentrations on licorice growth parameters, acquisition of C (carbon), nitrogen (N), and phosphorus (P) and on soil enzyme activities under saline and non-saline soil conditions. Pyrolysis char from maize (600 °C) was used at concentrations of 2% (B2), 4% (B4), and 6% (B6) for pot experiments. After 40 days, biochar improved the shoot and root biomass of licorice by 80 and 41% under saline soil conditions. However, B4 and B6 did not have a significant effect on shoot growth. Furthermore, increased nodule numbers of licorice grown at B4 amendment were observed under both non-saline and saline conditions. The root architectural traits, such as root length, surface area, project area, root volume, and nodulation traits, also significantly increased by biochar application at both B2 and B4. The concentrations of N and K in plant tissue increased under B2 and B4 amendments compared to the plants grown without biochar application. Moreover, the soil under saline conditions amended with biochar showed a positive effect on the activities of soil fluorescein diacetate hydrolase, proteases, and acid phosphomonoesterases. Overall, this study demonstrated the beneficial effects of maize-derived biochar on growth and nutrient uptake of licorice under saline soil conditions by improving nodule formation and root architecture, as well as soil enzyme activity., Peer Reviewed

The natural environment has been significantly altered by human activity over the past few decades. There is evidence we are now experiencing the sixth mass extinction, as many species of plants and animals are declining in abundance. We focused on the Orchidaceae because this plant family has experienced one of the biggest reductions in distribution. We investigated patterns in species richness and distribution of orchids, the rate and causes of their decrease and extinction, and factors influencing their occurrence in the Czech Republic and Greece. The key findings are: (i) Method of pollination and type of rooting system are associated with their distributions and they are different in the two countries. We assume that these differences might be due to the difference in the orography, distribution of suitable habitats and types of bedrock in these two countries. (ii) The greatest reduction in distribution was recorded for critically endangered taxa of orchids. The number of sites suitable for orchids in the Czech Republic declined by 8–92%. The most threatened orchid species are Spiranthes spiralis, Anacamptis palustris, Epipogium aphyllum and Goodyera repens. The distribution of orchids in the Czech Republic is mainly determined by the distribution of their habitats. (iii) The most important factor affecting the distribution of Czech orchids in South Bohemia is land cover. And the most important types of habitats (types in KVES) are oak and oak-hornbeam forests and agricultural meadows. Based on this information, it should be possible to improve the management that is crucial for maintaining orchid localities.

Aims: Root exudates are known to shape microbial activities in the rhizosphere and to be of fundamental importance for plant-soil-microbe-carbon–nitrogen interactions. However, it remains unclear how and to what extent the amount and composition of root exudation affects rhizosphere denitrification. Methods: In this study root exudation patterns and rhizosphere denitrification enzyme activity of three different grass species grown on two agricultural soils under two different soil water contents were investigated under controlled conditions. Results: We found that root exudation of primary metabolites largely depends on plant species, soil type, soil moisture and root exudation medium. In dependence of soil properties and soil moisture levels, plants largely controlled amount and quality of root exudation. Exudates affected denitrification activity and plant–microbe competition for nitrate. Specifically, exudation of organic acids stimulated denitrifying activity while the sugar lyxose exhibited an inhibitory effect. Conclusion: We show that interactive effects of physicochemical soil properties and species-specific effects of plant metabolism on root exudation act as a dominant control of rhizosphere denitrification, thereby explaining more than half of its variance. © 2021, The Author(s).

Bacillus subtilis EA-CB0575 is a plant growth-promoting bacterium (PGPB) associated with banana and tomato crops. Root colonization is an important trait for PGPB microorganisms and potentiates the bacterial effect related to the mechanisms of plant growth promotion. Therefore, detection of bacterial colonization of roots in different culture systems is important in the study of plant–microorganism interactions. In this study, fluorescent in situ hybridization (FISH) and catalyzed reporter deposition–FISH (CARD–FISH) were evaluated to determine the colonization ability of B. subtilis EA-CB0575 on banana and tomato roots planted on solid and liquid Murashige and Skoog medium (MS(S) and MS(L), respectively) and in soil for tomato plants. Results showed B. subtilis colonization 0–30 days post inoculation for banana and tomato plants in different culture systems with differential distribution of bacterial cells along tomato and banana roots. FISH and CARD–FISH methodologies were both successful in detecting B. subtilis colonies, but CARD–FISH proved to be superior due to its enhanced fluorescence signal. The presence of bacteria correlated with the promotion of plant growth in both plant species, providing clues to relate rhizospheric colonization with improvement in plant growth. FISH and CARD–FISH analysis results suggested the presence of native microbiota on the roots of in vitro banana plants, but not on those of tomato plants. © 2018 Elsevier GmbH

Licorice (Glycyrrhiza uralensis Fisch.) is a salt and drought tolerant legume suitable for rehabilitating abandoned saline lands, especially in dry arid regions. We hypothesized that soil amended with maize-derived biochar might alleviate salt stress in licorice by improving its growth, nutrient acquisition, and root system adaptation. Experiments were designed to determine the effect of different biochar concentrations on licorice growth parameters, acquisition of C (carbon), nitrogen (N), and phosphorus (P) and on soil enzyme activities under saline and non-saline soil conditions. Pyrolysis char from maize (600 °C) was used at concentrations of 2% (B2), 4% (B4), and 6% (B6) for pot experiments. After 40 days, biochar improved the shoot and root biomass of licorice by 80 and 41% under saline soil conditions. However, B4 and B6 did not have a significant effect on shoot growth. Furthermore, increased nodule numbers of licorice grown at B4 amendment were observed under both non-saline and saline conditions. The root architectural traits, such as root length, surface area, project area, root volume, and nodulation traits, also significantly increased by biochar application at both B2 and B4. The concentrations of N and K in plant tissue increased under B2 and B4 amendments compared to the plants grown without biochar application. Moreover, the soil under saline conditions amended with biochar showed a positive effect on the activities of soil fluorescein diacetate hydrolase, proteases, and acid phosphomonoesterases. Overall, this study demonstrated the beneficial effects of maize-derived biochar on growth and nutrient uptake of licorice under saline soil conditions by improving nodule formation and root architecture, as well as soil enzyme activity., Peer Reviewed

In this study, grafted and own-rooted young hazelnut plants of three high-quality cultivars were cultivated in Central Italy to investigate possible differences in growth, fruit and flower production, and physiological processes encompassing water uptake, photosynthetic variables and non-structural carbohydrate allocation. Stable isotopes and photosynthetic measurements were used to study carbon and water fluxes in plants. For the first time, an ecophysiological study was carried out to understand the seasonal growth dynamics of grafted plants in comparison with own-rooted plants. The own-rooted hazelnuts showed rapid above-ground development with large canopy volume, high amount of sprouts and earlier yield. The grafted plants showed greater below-ground development with lower canopy volumes and lower yield. However, later, the higher growth rates of the canopy led these plants to achieve the same size as that of the own-rooted hazelnuts and to enter the fruit production phase. Different seasonal behaviour in root water uptake and leaf photosynthesis-related variables was detected between the two types of plants. The grafted plants showed root development that allowed deeper water uptake than that of the own-rooted hazelnuts. Moreover, the grafted plants were characterized by a higher accumulation of carbohydrate reserves in their root tissues and by higher stomatal reactivity, determining significant plasticity in response to seasonal thermal variations.

Although studied for more than a century, the spatial distribution of microorganisms in a root system still remains partly understood. In a repeated greenhouse experiment using the model plant Brachypodium distachyon, we investigated the composition and distribution of rhizosphere bacteria and their response to inoculation with artificially selected microbial communities, using two different sampling scales: root sections from distinct individual roots (apical, middle, and rear sections) and the remaining entire system recovered after homogenization. Using 16S rRNA gene sequencing, we identified that root section identity was the most influential factor on the microbiota composition (R2 = 44.4%), followed by batch (R2 = 34.4%), and plant identity (R2 = 15.2%). Apical sections were characterized by increased abundances for Firmicutes members, while the rear sections featured more Verrucomicrobia. Root section sampling showed better sensitivity at detecting significant effects of the inoculation on the microbiota composition (e.g., local influence of inoculation on rear sections), in contrast, the homogenized sampling showed improved reproducibility (e.g., smaller sample dispersion). The comparison of the two sampling strategies highlighted a clear tradeoff between reproducibility and sensitivity, encouraging to complement traditional approaches with fine-scale sampling to improve our capacity to understand biological effects that could be otherwise missed.

[ES] En los años 90, se produjo un cambio en el sistema de cultivo del olivo ante la necesidad de reducir los costes de producción y aumentar la rentabilidad de las explotaciones. España, como primer productor mundial de aceituna para almazara fue pionero en la implantación del cultivo forzado del olivo, siendo en la actualidad el país con mayor extensión. Los sistemas forzados de cultivo se caracterizan por un aumento en la densidad de plantación, cambios en la formación y poda del arbolado, un aumento de las necesidades de fertirrigación y un aumento en la producción. Al mismo tiempo que se cambian los sistemas de cultivo se ha visto en los últimos años, un aumento en el uso de bioestimulantes en estos sistemas de cultivo ya que proporcionan ventajas al cultivo, como el aumento de la eficiencia en el uso de nutrientes o el aumento de la disponibilidad de nutrientes inmovilizados en el suelo o en la rizosfera. En el presente Trabajo Fin de Máster se ha comparado y estudiado la respuesta tanto del sistema de raíces como del sistema vegetativo frente al aporte de cuatro bioestimulantes de raíz. Se ha estudiado también su influencia sobre la floración y el cuajado, teniendo en cuenta la orientación y la posición en el árbol. Para ello se ha emulado un cultivo forzado en macetas con olivos del cultivar arbequina, ubicadas en la Universitat Politècnica de València, en condiciones de cultivo intensivo a las que se les aplicó tratamientos periódicos de cuatro bioestimulantes y un testigo para establecer comparaciones. Por otro lado, se ha aprovechado el ensayo destructivo que se realizó, para describir la morfología del sistema vegetativo y del sistema de raíces del cultivar Arbequina, bajo los diferentes bioestimulantes ensayados. Este trabajo ha comprobado que el 95% de la producción se concentra en la parte externa del ramo sin verse afectada esta producción por el sombreado pero sí por la orientación. Se ha podido establecer la influencia de los bioestimulantes ensaya, [EN] Spain is the world's first producer of olives for oil. In the nineteenth, the olive crop system changed due to the lack of profitability of farms and the increase in production costs. For these reasons, this country implemented the forced crop system of olive trees firstly. Nowadays, Spain is the country with more forced crop area. Forced crop systems are characterized by an increase in trees density, changes in the formation and pruning of the tree, an increase in fertirrigation needs and finally an increase in production. In recent years, while the olive crop system are changing, farmers are increasing the use of biostimulants in that crop systems. Biostimulants have many advantages such as an increasing efficiency in the use of nutrients or increasing the availability of immobilization nutrients in the soil or in the rhizosphere. In this essay we studied and compared the response of both vegetative and radical systems to four biostimulants contents. Moreover, we studied their influence over blooming and setting considering the position and the direction on the tree. For this essay we stablished a forced Arbequina olive crop system in pots at the Universistat Politècnica de València by intensive crop system condition. For this, individual treatments were performed with four biostimulants and a test to establish comparisons. On the other hand, taking advantage of the destructive essay to be carried out, we described the morphology of the vegetative system and the root system of the Arbequina cultivar, under the influence of the different biostimulants applied. This work has verified that 95% of the production is concentrated in the external part of the branch, without this production being affected by shading but by orientation. It has been possible to establish the influence of the biostimulants tested in each of the phases of the productive cycle as well as the biomass of the root system., [CA] En els anys 90, es va produir un canvi en el sistema de cultiu de l’olivera degut a la necessitat de reduir els costos de producció i augmentar la rentabilitat de les explotacions. Espanya, com a primer productor mundial d’oliva destinada a la producció d’oli, va ser pioner en la implantació del cultiu forçat de l’olivera, i actualement es el país amb més extensió. Els sistemas forçats de cultiu es caracteritzen per un augment en la densitat de plantació, canvis en la formació i poda dels arbres, un augment de les necessitats de fertirrigació i un augment final de la producció. Al mateix temps que es canvien els sistemes de cultiu s’ha observat durant els darrers anys, un augment en l’ús de bioestimulants en aquests nous sistemes de cultiu ja que proporcionen aventatges al cultiu, com per exemple un augment de l’eficiència en l’ús dels nutrients o un augment de la disponibilitat de nutrients inmovilitzats al sòl o a la rizosfera. En el present Treball Fi de Màster s’ha comparat i estudiat la resposta tant del sistema d’arrels com del sistema vegetatiu davant l’aport de tres bioestimulants d’arrel, també s’ha analitzat la seva influència en la floració i el quallat tenint en compte l’orientació i la posició en l’arbre. Per poder realitzar l’estudi s’emulà un cultiu forçat en testos amb oliveres del cultivar Arbequina, ubicades a la Universitat Politècnica de València en condicions de cultiu intensiu a les quals sel’s hi aplicà tractaments periòdics de quatre biostimulants i un testig per a establir comparacions. D’altre banda, aprofitant l’assaig destructiu que es realitzà, s’ha descrit la morfología del sistema vegetatiu i del sistema d’arrels del cultivar Arbequina, sota els diferents bioestimulants assajats. En aquest treball s’ha comprovat que el 95% de la producción es concentra a la part externa de l’arbre sense que la producción es vegi afectada pel sombrejat però sí per l’orientació. S’ha pogut establir la influència dels bioestimulants assajats en cada

Theory states that tree growth in lowland tropical forests on old, weathered soils is limited by low phosphorous (P) availability. However, evidence for P limitation from nutrient manipulation experiments remains unclear, which raises the question whether trees are taking up added P. In French Guianese lowland rainforest, we measured changes in nitrogen (N) and P availability before and up to two months after N and P addition. We measured in soils with intact root systems and soils excluding roots and mycorrhizal fungi with root exclusion cylinders. When the root system was excluded, P addition increased P availability to a much greater extent and for a longer time than where the roots remained undisturbed. N dynamics were unaffected by root presence/absence. These results indicate rapid root uptake of P, but not of N, suggesting very effective P acquisition in these lowland rainforests.

In plant cells, cadmium (Cd) and arsenic (As) exert toxicity mainly by inducing oxidative stress through an imbalance between the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), and their detoxification. Nitric oxide (NO) is a RNS acting as signalling molecule coordinating plant development and stress responses, but also as oxidative stress inducer, depending on its cellular concentration. Peroxisomes are versatile organelles involved in plant metabolism and signalling, with a role in cellular redox balance thanks to their antioxidant enzymes, and their RNS (mainly NO) and ROS. This study analysed Cd or As effects on peroxisomes, and NO production and distribution in the root system, including primary root (PR) and lateral roots (LRs). Arabidopsis thaliana wild-type and transgenic plants enabling peroxisomes to be visualized in vivo, through the expression of the 35S-cyan fluorescent protein fused to the peroxisomal targeting signal1 (PTS1) were used. Peroxisomal enzymatic activities including the antioxidant catalase, the HO-generating glycolate oxidase, and the hydroxypyruvate reductase, and root system morphology were also evaluated under Cd/As exposure. Results showed that Cd and As differently modulate these activities, however, catalase activity was inhibited by both. Moreover, Arabidopsis root system was altered, with the pollutants differently affecting PR growth, but similarly enhancing LR formation. Only in the PR apex, and not in LR one, Cd more than As caused significant changes in peroxisome distribution, size, and in peroxisomal NO content. By contrast, neither pollutant caused significant changes in peroxisomes size and peroxisomal NO content in the LR apex.

[ES] En los años 90, se produjo un cambio en el sistema de cultivo del olivo ante la necesidad de reducir los costes de producción y aumentar la rentabilidad de las explotaciones. España, como primer productor mundial de aceituna para almazara fue pionero en la implantación del cultivo forzado del olivo, siendo en la actualidad el país con mayor extensión. Los sistemas forzados de cultivo se caracterizan por un aumento en la densidad de plantación, cambios en la formación y poda del arbolado, un aumento de las necesidades de fertirrigación y un aumento en la producción. Al mismo tiempo que se cambian los sistemas de cultivo se ha visto en los últimos años, un aumento en el uso de bioestimulantes en estos sistemas de cultivo ya que proporcionan ventajas al cultivo, como el aumento de la eficiencia en el uso de nutrientes o el aumento de la disponibilidad de nutrientes inmovilizados en el suelo o en la rizosfera. En el presente Trabajo Fin de Máster se ha comparado y estudiado la respuesta tanto del sistema de raíces como del sistema vegetativo frente al aporte de cuatro bioestimulantes de raíz. Se ha estudiado también su influencia sobre la floración y el cuajado, teniendo en cuenta la orientación y la posición en el árbol. Para ello se ha emulado un cultivo forzado en macetas con olivos del cultivar arbequina, ubicadas en la Universitat Politècnica de València, en condiciones de cultivo intensivo a las que se les aplicó tratamientos periódicos de cuatro bioestimulantes y un testigo para establecer comparaciones. Por otro lado, se ha aprovechado el ensayo destructivo que se realizó, para describir la morfología del sistema vegetativo y del sistema de raíces del cultivar Arbequina, bajo los diferentes bioestimulantes ensayados. Este trabajo ha comprobado que el 95% de la producción se concentra en la parte externa del ramo sin verse afectada esta producción por el sombreado pero sí por la orientación. Se ha podido establecer la influencia de los bioestimulantes ensaya, [EN] Spain is the world's first producer of olives for oil. In the nineteenth, the olive crop system changed due to the lack of profitability of farms and the increase in production costs. For these reasons, this country implemented the forced crop system of olive trees firstly. Nowadays, Spain is the country with more forced crop area. Forced crop systems are characterized by an increase in trees density, changes in the formation and pruning of the tree, an increase in fertirrigation needs and finally an increase in production. In recent years, while the olive crop system are changing, farmers are increasing the use of biostimulants in that crop systems. Biostimulants have many advantages such as an increasing efficiency in the use of nutrients or increasing the availability of immobilization nutrients in the soil or in the rhizosphere. In this essay we studied and compared the response of both vegetative and radical systems to four biostimulants contents. Moreover, we studied their influence over blooming and setting considering the position and the direction on the tree. For this essay we stablished a forced Arbequina olive crop system in pots at the Universistat Politècnica de València by intensive crop system condition. For this, individual treatments were performed with four biostimulants and a test to establish comparisons. On the other hand, taking advantage of the destructive essay to be carried out, we described the morphology of the vegetative system and the root system of the Arbequina cultivar, under the influence of the different biostimulants applied. This work has verified that 95% of the production is concentrated in the external part of the branch, without this production being affected by shading but by orientation. It has been possible to establish the influence of the biostimulants tested in each of the phases of the productive cycle as well as the biomass of the root system., [CA] En els anys 90, es va produir un canvi en el sistema de cultiu de l’olivera degut a la necessitat de reduir els costos de producció i augmentar la rentabilitat de les explotacions. Espanya, com a primer productor mundial d’oliva destinada a la producció d’oli, va ser pioner en la implantació del cultiu forçat de l’olivera, i actualement es el país amb més extensió. Els sistemas forçats de cultiu es caracteritzen per un augment en la densitat de plantació, canvis en la formació i poda dels arbres, un augment de les necessitats de fertirrigació i un augment final de la producció. Al mateix temps que es canvien els sistemes de cultiu s’ha observat durant els darrers anys, un augment en l’ús de bioestimulants en aquests nous sistemes de cultiu ja que proporcionen aventatges al cultiu, com per exemple un augment de l’eficiència en l’ús dels nutrients o un augment de la disponibilitat de nutrients inmovilitzats al sòl o a la rizosfera. En el present Treball Fi de Màster s’ha comparat i estudiat la resposta tant del sistema d’arrels com del sistema vegetatiu davant l’aport de tres bioestimulants d’arrel, també s’ha analitzat la seva influència en la floració i el quallat tenint en compte l’orientació i la posició en l’arbre. Per poder realitzar l’estudi s’emulà un cultiu forçat en testos amb oliveres del cultivar Arbequina, ubicades a la Universitat Politècnica de València en condicions de cultiu intensiu a les quals sel’s hi aplicà tractaments periòdics de quatre biostimulants i un testig per a establir comparacions. D’altre banda, aprofitant l’assaig destructiu que es realitzà, s’ha descrit la morfología del sistema vegetatiu i del sistema d’arrels del cultivar Arbequina, sota els diferents bioestimulants assajats. En aquest treball s’ha comprovat que el 95% de la producción es concentra a la part externa de l’arbre sense que la producción es vegi afectada pel sombrejat però sí per l’orientació. S’ha pogut establir la influència dels bioestimulants assajats en cada

Root water uptake is a key ecohydrological process for which a physically-based understanding has been developed in the past decades. However, due to methodological constraints, knowledge gaps remain about the plastic response of whole plant root systems to a rapidly changing environment. - We designed a laboratory system for non-destructive monitoring of stable isotopic composition in plant transpiration of an herbaceous species (Centaurea jacea) and of soil water across depths, taking advantage of newly developed in-situ methods. Daily root water uptake profiles were obtained using a statistical Bayesian multi-source mixing model. - Fast shifts in the isotopic composition of both soil and transpiration water could be observed with the setup and translated into dynamic and pronounced shifts of the root water uptake profile, even in well-watered conditions. - The incorporation of plant physiological and soil physical information into statistical modelling improved the model output. A simple exercise of water balance closure underlined the non-unique relationship between root water uptake profile on the one hand, and water content and root distribution profiles on the other, illustrating the continuous adaption of the plant water uptake as a function of its root hydraulic architecture and soil water availability during the experiment

[ES] En los años 90, se produjo un cambio en el sistema de cultivo del olivo ante la necesidad de reducir los costes de producción y aumentar la rentabilidad de las explotaciones. España, como primer productor mundial de aceituna para almazara fue pionero en la implantación del cultivo forzado del olivo, siendo en la actualidad el país con mayor extensión. Los sistemas forzados de cultivo se caracterizan por un aumento en la densidad de plantación, cambios en la formación y poda del arbolado, un aumento de las necesidades de fertirrigación y un aumento en la producción. Al mismo tiempo que se cambian los sistemas de cultivo se ha visto en los últimos años, un aumento en el uso de bioestimulantes en estos sistemas de cultivo ya que proporcionan ventajas al cultivo, como el aumento de la eficiencia en el uso de nutrientes o el aumento de la disponibilidad de nutrientes inmovilizados en el suelo o en la rizosfera. En el presente Trabajo Fin de Máster se ha comparado y estudiado la respuesta tanto del sistema de raíces como del sistema vegetativo frente al aporte de cuatro bioestimulantes de raíz. Se ha estudiado también su influencia sobre la floración y el cuajado, teniendo en cuenta la orientación y la posición en el árbol. Para ello se ha emulado un cultivo forzado en macetas con olivos del cultivar arbequina, ubicadas en la Universitat Politècnica de València, en condiciones de cultivo intensivo a las que se les aplicó tratamientos periódicos de cuatro bioestimulantes y un testigo para establecer comparaciones. Por otro lado, se ha aprovechado el ensayo destructivo que se realizó, para describir la morfología del sistema vegetativo y del sistema de raíces del cultivar Arbequina, bajo los diferentes bioestimulantes ensayados. Este trabajo ha comprobado que el 95% de la producción se concentra en la parte externa del ramo sin verse afectada esta producción por el sombreado pero sí por la orientación. Se ha podido establecer la influencia de los bioestimulantes ensaya, [EN] Spain is the world's first producer of olives for oil. In the nineteenth, the olive crop system changed due to the lack of profitability of farms and the increase in production costs. For these reasons, this country implemented the forced crop system of olive trees firstly. Nowadays, Spain is the country with more forced crop area. Forced crop systems are characterized by an increase in trees density, changes in the formation and pruning of the tree, an increase in fertirrigation needs and finally an increase in production. In recent years, while the olive crop system are changing, farmers are increasing the use of biostimulants in that crop systems. Biostimulants have many advantages such as an increasing efficiency in the use of nutrients or increasing the availability of immobilization nutrients in the soil or in the rhizosphere. In this essay we studied and compared the response of both vegetative and radical systems to four biostimulants contents. Moreover, we studied their influence over blooming and setting considering the position and the direction on the tree. For this essay we stablished a forced Arbequina olive crop system in pots at the Universistat Politècnica de València by intensive crop system condition. For this, individual treatments were performed with four biostimulants and a test to establish comparisons. On the other hand, taking advantage of the destructive essay to be carried out, we described the morphology of the vegetative system and the root system of the Arbequina cultivar, under the influence of the different biostimulants applied. This work has verified that 95% of the production is concentrated in the external part of the branch, without this production being affected by shading but by orientation. It has been possible to establish the influence of the biostimulants tested in each of the phases of the productive cycle as well as the biomass of the root system., [CA] En els anys 90, es va produir un canvi en el sistema de cultiu de l’olivera degut a la necessitat de reduir els costos de producció i augmentar la rentabilitat de les explotacions. Espanya, com a primer productor mundial d’oliva destinada a la producció d’oli, va ser pioner en la implantació del cultiu forçat de l’olivera, i actualement es el país amb més extensió. Els sistemas forçats de cultiu es caracteritzen per un augment en la densitat de plantació, canvis en la formació i poda dels arbres, un augment de les necessitats de fertirrigació i un augment final de la producció. Al mateix temps que es canvien els sistemes de cultiu s’ha observat durant els darrers anys, un augment en l’ús de bioestimulants en aquests nous sistemes de cultiu ja que proporcionen aventatges al cultiu, com per exemple un augment de l’eficiència en l’ús dels nutrients o un augment de la disponibilitat de nutrients inmovilitzats al sòl o a la rizosfera. En el present Treball Fi de Màster s’ha comparat i estudiat la resposta tant del sistema d’arrels com del sistema vegetatiu davant l’aport de tres bioestimulants d’arrel, també s’ha analitzat la seva influència en la floració i el quallat tenint en compte l’orientació i la posició en l’arbre. Per poder realitzar l’estudi s’emulà un cultiu forçat en testos amb oliveres del cultivar Arbequina, ubicades a la Universitat Politècnica de València en condicions de cultiu intensiu a les quals sel’s hi aplicà tractaments periòdics de quatre biostimulants i un testig per a establir comparacions. D’altre banda, aprofitant l’assaig destructiu que es realitzà, s’ha descrit la morfología del sistema vegetatiu i del sistema d’arrels del cultivar Arbequina, sota els diferents bioestimulants assajats. En aquest treball s’ha comprovat que el 95% de la producción es concentra a la part externa de l’arbre sense que la producción es vegi afectada pel sombrejat però sí per l’orientació. S’ha pogut establir la influència dels bioestimulants assajats en cada

Theory states that tree growth in lowland tropical forests on old, weathered soils is limited by low phosphorous (P) availability. However, evidence for P limitation from nutrient manipulation experiments remains unclear, which raises the question whether trees are taking up added P. In French Guianese lowland rainforest, we measured changes in nitrogen (N) and P availability before and up to two months after N and P addition. We measured in soils with intact root systems and soils excluding roots and mycorrhizal fungi with root exclusion cylinders. When the root system was excluded, P addition increased P availability to a much greater extent and for a longer time than where the roots remained undisturbed. N dynamics were unaffected by root presence/absence. These results indicate rapid root uptake of P, but not of N, suggesting very effective P acquisition in these lowland rainforests.

Theory states that tree growth in lowland tropical forests on old, weathered soils is limited by low phosphorous (P) availability. However, evidence for P limitation from nutrient manipulation experiments remains unclear, which raises the question whether trees are taking up added P. In French Guianese lowland rainforest, we measured changes in nitrogen (N) and P availability before and up to two months after N and P addition. We measured in soils with intact root systems and soils excluding roots and mycorrhizal fungi with root exclusion cylinders. When the root system was excluded, P addition increased P availability to a much greater extent and for a longer time than where the roots remained undisturbed. N dynamics were unaffected by root presence/absence. These results indicate rapid root uptake of P, but not of N, suggesting very effective P acquisition in these lowland rainforests.

In plant cells, cadmium (Cd) and arsenic (As) exert toxicity mainly by inducing oxidative stress through an imbalance between the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), and their detoxification. Nitric oxide (NO) is a RNS acting as signalling molecule coordinating plant development and stress responses, but also as oxidative stress inducer, depending on its cellular concentration. Peroxisomes are versatile organelles involved in plant metabolism and signalling, with a role in cellular redox balance thanks to their antioxidant enzymes, and their RNS (mainly NO) and ROS. This study analysed Cd or As effects on peroxisomes, and NO production and distribution in the root system, including primary root (PR) and lateral roots (LRs). Arabidopsis thaliana wild-type and transgenic plants enabling peroxisomes to be visualized in vivo, through the expression of the 35S-cyan fluorescent protein fused to the peroxisomal targeting signal1 (PTS1) were used. Peroxisomal enzymatic activities including the antioxidant catalase, the HO-generating glycolate oxidase, and the hydroxypyruvate reductase, and root system morphology were also evaluated under Cd/As exposure. Results showed that Cd and As differently modulate these activities, however, catalase activity was inhibited by both. Moreover, Arabidopsis root system was altered, with the pollutants differently affecting PR growth, but similarly enhancing LR formation. Only in the PR apex, and not in LR one, Cd more than As caused significant changes in peroxisome distribution, size, and in peroxisomal NO content. By contrast, neither pollutant caused significant changes in peroxisomes size and peroxisomal NO content in the LR apex.

Roots are known to use biopores as preferential growth pathways to overcome hard soil layers and access subsoil water resources. This study evaluates root- biopore interactions at the root-system scale under different soil physical and environmental conditions using a mechanistic simulation model and extensive experimental field data. In a field experiment, spring wheat (Triticum aestivum L.) was grown on silt loam with a large biopore density. X-ray computed tomography scans of soil columns from the field site were used to provide a realistic biopore network as input for the three-dimensional numerical R-SWMS model, which was then applied to simulate root architecture as well as water flow in the root-biopore-soil continuum. The model was calibrated against observed root length densities in both the bulk soil and biopores by optimizing root growth model input parameters. By implementing known interactions between root growth and soil penetration resistance into our model, we could simulate root systems whose response to biopores in the soil corresponded well to experimental observations described in the literature, such as increased total root length and increased rooting depth. For all considered soil physical (soil texture and bulk density) and environmental conditions (years of varying dryness), we found biopores to substantially mitigate transpiration deficits in times of drought by allowing roots to take up water from wetter and deeper soil layers. This was even the case when assuming reduced root water uptake in biopores due to limited root-soil contact. The beneficial impact of biopores on root water uptake was larger for more compact and less conductive soils.

The root system is the plant’s organ that has the important function of taking up water and plant nutrients from the soil. Root system functioning depends on its multiscale structure: the size and structure of cells in the conductive tissues, the development and spatial organization of tissues, and the network of root segments that make up the root system. Breeders select for these structural properties of roots and root systems to develop crop varieties with high water and nutrient efficiencies that give a high or stable yield under non-controllable adverse environmental conditions(droughts, nutrient poor soils, soil salinity, …). But, a direct relation between the functioning of a root system and its structure is not at hand. Functional-structural root system models that simulate the relations between root architectural and hydraulic properties, and the spatio-temporal patterns of water and solute fluxes in the root zone can therefore play an important role in this selection process. However, it must be first demonstrated that these models accurately reproduce the processes they intend to describe but this is a challenging task for two reasons. First, the root system is the so-called ‘hidden halve’ of the plant so that its structure and the flow and transport processes in the soil towards individual roots are hard to observe. Secondly, the properties that control water flow in root segments and that are required as input parameters in structural-functional root models vary with age and root order and quantitative information about these relations is scarce. In this paper, we demonstrate how this deadlock could be broken by combining co-registered root structure and tracer distributions obtained from magnetic resonance imaging, a functional-structural root system model, and inverse modeling. The main features in the tracer patterns were well reproduced by the model using root hydraulic parameters that were obtained using inverse modeling and that were found to corr

Plant transpiration and root water uptake are dependent on multiple traits that interact with site soil characteristics and environmental factors such as radiation, atmospheric temperature, relative humidity, and soil-moisture content. Models of root architecture and functions are increasingly employed to simulate root-soil interactions. Root water uptake is thereby affected by the root hydraulic architecture, the soil moisture conditions, soil hydraulic properties and the transpiration demand as controlled by atmospheric conditions. Stomatal conductance plays a vital role in regulating transpiration in plants. Isohydric plants follow the strategy to close their stomata in order to maintain the leaf water potential at a constant level, while anisohydric plants leave their stomata open when leaf water potentials fall due to drought stress. Modeling the stomatal regulation effectively will result in a more reliable model that will regulate the excessive loss of water. We performed the simulations of plant water uptake and transpiration on a DUNE-based simulator DuMux. It simulates the flow and transport processes in porous media that can represent the porous medium (including soil) with embedded hierarchical biological networks (in this case, root system). We implemented hydraulic and chemical stomatal control of root water uptake in DuMux following the current approach where stomatal control is regulated by simulated water potential and/or chemical signal concentration. We then performed a mesh convergence study in order to verify the accuracy of our results. Finally, we conducted the simulations for different scenarios to study the effect of hydraulic and chemical regulation on root system performance under drought stress. Future work will include incorporating further modeling capabilities into DuMux which will facilitate the consideration of further soil and rhizosphere processes in the simulations, such as nutrients, root exudes or soil microorganisms.

The paper addresses the operation of a cylindrical brush with elastic rods of bristles at the disclosure of the root system of maternal plants. It has been established that the basic components of the resistance force in the operation of a given brush is the sum of resistances caused by the soil viscosity force, the static resistance of loose particles of soil and the resistance force at removing soil particles. Based on the minimization of costs of energy, the optimal kinematical parameters have been defined for the brush with a vertical rotation axis. The value for the total resistance force is largely affected by the angular speed of the brush. In addition to the resistance force, the rods of the brush bristles are exposed to the normal reaction from the soil base. By deriving the resultant of these two forces using a method of the Legendre elliptic integrals, we have established the optimal dimensional parameters for the rods of bristles made of polypropylene. A given method has made it possible to take into consideration their significant, compared with the rods’ length, deformations as a result of their bending. The rods’ length has been determined to be the maximally possible one to ensure the conditions for the removal of soil from a swath that covers the root system of maternal plants of clonal rootstock. In addition, the influence of the friction force during brush operation has been investigated. This implies friction among soil particles and against the surface of the bristle rods. It was determined that the forces of friction, as well as the normal reaction of soil, have little effect on the operation of a cylindrical brush while opening the root system of maternal plants. This is due to the lack of a solid foundation when a bristle rod is at work, which in turn makes it possible to arrange the bristle rods one by one at the surface of the brush. The absence of necessity in the considerable relative stiffness makes it possible for the bristle rods to re, Рассмотрены вопросы работы цилиндрической щетки с гибкими прутьями ворса при раскрытии корневой системы маточных растений. Установлено, что основными составляющими силы сопротивления при работе данной щетки является сумма сопротивлений, вызванных силой вязкости грунта, силой статического сопротивления сыпучих частиц почвы и силой сопротивления отбрасывания частиц почвы. Исходя из минимизации затрат энергии определены оптимальные кинематические параметры щетки с вертикальной осью вращения. Большое влияние на значение общей силы сопротивления имеет угловая скорость щетки. Кроме силы сопротивления на прутки ворса щетки действует нормальная реакция грунтового основания. Найдя результирующую двух сил с помощью метода эллиптических интегралов Лежандра установлены оптимальные размерные параметры прутков ворса, изготовленных из полипропилена. Данный метод позволил учесть значительные, по сравнению с длиной прутков, их деформации в результате их сгиба. Длина прутков определена как максимально возможная для обеспечения условия удаления грунта с валка, покрывающего корневую систему маточных растений клоновых подвоев. Также исследовано влияние силы трения во время работы щетки. Это трение частиц почвы между собой и по поверхности прутков ворса. Определено, что силы трения, как и нормальная реакция почвы, мало влияют на работу цилиндрической щетки при раскрытии корневой системы маточных растений. Это объясняется отсутствием твердой основы при работе прутка ворса, что в свою очередь позволяет размещать прутки ворса по одному на поверхности щетки. Отсутствие потребности в значительной относительной жесткости позволяет пруткам ворса удалять почву из валка минимизируя при этом повреждения растений. С помощью эллиптических интегралов Лежандра второго рода исследовано прогиб прутков ворса цилиндрической щетки при раскрытии корневой системы маточных растений. Величина прогиба прутка в процессе работы влияет на полноту удаления ним частиц почвы. При увеличении прогиба меняется угол межд, Розглянуто питання роботи циліндричної щітки з гнучкими прутками ворсу при розкритті кореневої системи маточних рослин. Встановлено, що основними складовими сили опору при роботі даної щітки є сума опорів, що спричинені силою в’язкості ґрунту, силою статичного опору сипучих частинок ґрунту та силою опору відкидання частинок ґрунту. Виходячи з мінімізації затрат енергії визначено оптимальні кінематичні параметри щітки з вертикальною віссю обертання. Великий влив на значення загальної сили опору має кутова швидкість щітки. Крім сили опору на прутки ворсу щітки діє нормальна реакція ґрунтової основи. Знайшовши результуючу цих двох сил за допомогою методу еліптичних інтегралів Лежандра встановлено оптимальні розмірні параметри прутків ворсу, що виготовлені з поліпропілену. Даний метод дозволив врахувати значні, у порівнянні з довжиною прутків, їх деформації в результаті їх згину. Довжина прутків визначена як максимально можлива для забезпечення умови видалення ґрунту з валка, що вкриває кореневу систему маточних рослин клонових підщеп. Також досліджено вплив сили тертя під час роботи щітки. Це тертя частинок ґрунту між собою та по поверхні прутків ворсу. Визначено, що сили тертя, як і нормальна реакція ґрунту, мало впливають на роботу циліндричної щітки при розкритті кореневої системи маточних рослин. Це пояснюється відсутністю твердої основи при роботі прутка ворсу, що в свою чергу дозволяє розміщувати прутки ворсу по одному на поверхні щітки. Відсутність потреби у значній відносній жорсткості дозволяє пруткам ворсу видаляти ґрунт з валка мінімізуючи при цьому пошкодження рослин. За допомогою еліптичних інтегралів Лежандра другого роду досліджено прогин прутків ворсу циліндричної щітки при розкритті кореневої системи маточних рослин. Величина прогину прутка в процесі роботи впливає на повноту видалення ним частинок ґрунту. При збільшення прогину змінюється кут між робочою гранню прутка ворсу і поверхнею ґрунту. Це призводить до зменшення видалення частинок і збільшення

Worldwide ecosystems primary production and survival are largely limited by soil water availability, and affected by plant traits that control water uptake, transport, and release in the atmosphere. In order to understand how these complex systems will react to future climates, and optimally adjust their management, the development of experimental and modelling approaches is crucial. In particular, integrating process-based representations plant hydraulics and stomatal closure in land surface models (LSMs) is a major challenge as the limited computational resources necessitate the use of simplified descriptions of these processes. We present methods used to identify scale consistent emergent principles governing water flow in plants. We show that simplistic mechanistic expressions arise from the cell to the root system scale, and along stems whose geometry, saturated conductivity, sensitivity to cavitation, and leaf area vary continuously with height. Our results support that cavitation is a whole-stem emergent property; in which compounding effects of gravity and vertical traits variations reported experimentally all substantially contribute to the occurrence of hydraulic failure in tall trees, and need to be accounted for in LSMs. Furthermore, a macroscopic solution of water flow in plant hydraulic architectures was implemented in the Terrestrial Systems Modeling Platform. As compared to the standard approach, this new model of water capture characteristically exhibits a different sensitivity of the onset of water stress to root distribution and soil properties.

Climatic projections indicate that, Belgium might face a significant change in rainfall regime with up to 25% less precipitations in Summer by the end of the 21st century. This would lead to water stresses for plants. Grasslands, that make for a large part of Belgian agricultural system would be amongst the most affected by these dryer conditions and would be likely to see their yields decrease. To tackle the issue, UCLouvain launched the ForDrought project in 2012, whose overal goal is to improve the performance of forage crops to cope with climate change. The specific objectives of this study were to observe the responses of root systems of grassland plants when facing a water deficit and to assess the effect of plant species association. The species studied were Dactylis glomerata and Medicago sativa. Large pits were dug in front of experimental agricutural parcels to carry out differents measurements on the root system. The root numbers in each pit were counted, soil samples containing roots were taken and the roots were analyzed genetically to determine the specie to which they belonged. In addition, the parcels were harvested and yield calculated four times over the course of one year. The results showed that a water deficit has an impact on the number of roots of both species. The genetic analyses showed, quite surprisingly, that Dactylis was not detected when it was alongside alfalfa. Finally, they showed that the yield is negatively impacted by water deficit while the association of species does not produce. (1) Taggart J.M., Cahill J.F., McNickle G.G., Hall J.C., (2011), Molecular identification of roots from a grassland community using size differences in fluorescently labelled PCR amplicons of three cpDNA regions: Molecular diagnostics and DNA taxonomy, Molecular Ecology Resources, 11,1, 185-195 (2) Robbins N.E., Dinneny J.R., (2015), The divining root: moisture-driven responses of roots at the micro- and macro-scale, Journal of Experimental Botany, 66

Climatic projections indicate that Europe should face a significant change in seasonal rainfall distribution, with up to 25% less precipitations in Summer by the end of the 21st century.. The yield of grasslands, that make for a large part of Belgian agricultural system, would be amongst the most affected by these new scenarios of water deficit. The ovseral goal of the ForDrought project, launched at UCLouvain in 2012, is to improve the performance of forage crops to cope with climate change. The specific objectives of this study were to observe the responses of root systems of grassland plants exposed to a water deficit and to assess the value of plant species association. The species studied were Dactylis glomerata and Medicago sativa. Large pits were dug on the border of experimental plots of pure and mixed composition, exposed or not to a one-month long summer drought, to carry out different root system observations. The number of roots in each pit were counted following the trench profile method. In addition, roots were extracted from vertical and horizontal soil cores and root DNA was analysed to determine the specific root distribution of each species. The parcels were harvested and yield measured four times over the course of one year. Finally, the soil profile and the depth of the ploughpan for each plot were also determined. The results showed that a water deficit had an impact on the root density of both species. However, this impact differed between species: Medicago had more roots when exposed to the deficit while Dactylis tended to produce fewer roots. The genetic analysis turned out to be biased against Dactylis which could not be detected when it was mixed with Medicago, despite many protocol adjustments were implemented to circumvent the problem. The yield was negatively impacted by water deficit, for all plots. The association of species did not produce any clear effect on the yield. However, the soil observation showed that the ploughpan was abnor

Agricultural yields critically depend on performance of the root system. Tree root system architecture and its development in time have indeed a key-impact under drought and nutrient stress conditions. Therefore, there is a need to monitor or phenotype root system, which is hidden in the soil. Electrical resistivity methods are promising for this task (Whalley et al., 2017) except that there is ambiguity in differentiating soil and root structures due to overlapping electrical conductivities of soil and root. Numerous studies also report the need for more accurate ERT methods of quantification of the root system at the plant scale, especially under field conditions (Ni et al.,2018). We previously demonstrated experimentally on a woody species (vineyard plant and orange trees) that current density distribution in the soil-root continuum could differ significantly depending on whether current is injected into the stem of the tree or in the soil surface close to stem (Mary et al., 2018). We explained this phenomenon by assuming that an injection into the stem is most likely to exit the root system only at fine root locations. Here, we present a preliminary modelling study using an explicit representation of root structure in the MALM forward modelling as a follow-up work to support the assumptions made and to understand better how this approach can be made more robust for field-scale root phenotyping. In this study, we quantified the sensitivity of the Mise-à-la-masse coupled with the ERT method to image the root system in respect to different soil water content (after Root Water Uptake). We also estimated how the contrast of resistivity between roots (for a range of resistance in inner layer of root, outer bark structure as well as fine roots), and different types of soil influence the geophysical measurements.

E8 is a famous root system in mathematics. Lisi claims in his paper “An Exceptionally Simple Theory of Everything” that there is a connection between the standard model of the elementary particles and this root system. He claims that standard model has the same structure as the root system E8. If this is true, there must be a mapping from the standard model to E8. This map must identify each elementary particle with an unique root of E8. Also the four charges (weak isospin, weak hypercharge, g3 and g8) of the standard model must have corresponding vectors in R8. These four charge vectors must have the property that taking the inner product of the charge vector and the root identified withan elementary particle, it would result in the charge of that particle. This is needed to guarantee that we have conservation of charge. In this paper we have shown that it is not possible to find a map with four charge vectors. This was done by studying root systems and how different root systems are present in E8 as sub root systems. We also proved that the intersection of E8 with the orthogonal complement of a charge, must be a root system. This limits the possibilities for the charge vectors. For these possible charges it has been checked whether there are enough roots for a given charge to identify the elementary particles. Since this was not the case, we concluded that no mapping with four charge vectors exists., Applied Mathematics | Applied Physics

Quinoa is a pseudocereal crop that is well adapted to a wide range of climatic conditions and has significant potential for increased production as a new crop in the Mediterranean region and in other parts of the world, including northern Europe, North America, Asia, and Africa. Because of its exceptional nutritional properties, quinoa is highly appreciated among humans as well as in animal nutrition for feeding both ruminants and nonruminating animals. Data obtained from several studies conducted in Greece, Italy, and Turkey demonstrate the high nutritional and functional potential of quinoa. Nitrogen fertilization has a positive effect on the growth and grain yield of quinoa crops. The biomass has high crude protein and low fiber and is competitive with alfalfa. The assessment of quinoa saponin content is of great importance for the industry. The highest saponin content and yield have been found under organic cropping systems. Oat, bean, and duckweed plants have a great phytotoxic response, especially to the inflorescence tissues of quinoa, confirming the potential allelopathic activity of this promising crop. The major part of the root system is concentrated in the upper 0–30 cm of the soil, and the root length density and root mass density increase with increasing applied nitrogen. In conclusion, quinoa may be suggested as a new alternative crop for semiarid and arid Mediterranean conditions affected by multiple abiotic stress factors because of its stress-tolerant characteristics, adaptability to several agro-ecological conditions, and nutritional and economic value.

—: Based on the analysis of dose–response relationships under exposure to a wide range of copper sulfate concentrations, the metal tolerance of seed progeny was assessed using the root elongation test in two morphological forms of Taraxacum officinale Wigg. s.l. growing in background and technogenically transformed areas (industrial waste dumps). Since previous studies in the same areas showed that these forms differed in their abundance and ratio in the coenopopulations and in the level of copper accumulation, it was assumed that they would also differ in the metal tolerance of seed progeny. It was found that the average values of effective copper sulfate concentrations inhibiting root growth in seedlings by 10, 50, and 90%, did not differ between the study areas and between the morphological forms of dandelion. © 2019, Pleiades Publishing, Ltd., The work was performed under state assignment for the Institute of Plant and Animal Ecology, Ural Branch, Russian Academy of Sciences and supported by the Integrated Research Program of the Ural Branch of the Russian Academy of Sciences (project no. 18-4-4-9).

Quinoa is a pseudocereal crop that is well adapted to a wide range of climatic conditions and has significant potential for increased production as a new crop in the Mediterranean region and in other parts of the world, including northern Europe, North America, Asia, and Africa. Because of its exceptional nutritional properties, quinoa is highly appreciated among humans as well as in animal nutrition for feeding both ruminants and nonruminating animals. Data obtained from several studies conducted in Greece, Italy, and Turkey demonstrate the high nutritional and functional potential of quinoa. Nitrogen fertilization has a positive effect on the growth and grain yield of quinoa crops. The biomass has high crude protein and low fiber and is competitive with alfalfa. The assessment of quinoa saponin content is of great importance for the industry. The highest saponin content and yield have been found under organic cropping systems. Oat, bean, and duckweed plants have a great phytotoxic response, especially to the inflorescence tissues of quinoa, confirming the potential allelopathic activity of this promising crop. The major part of the root system is concentrated in the upper 0–30 cm of the soil, and the root length density and root mass density increase with increasing applied nitrogen. In conclusion, quinoa may be suggested as a new alternative crop for semiarid and arid Mediterranean conditions affected by multiple abiotic stress factors because of its stress-tolerant characteristics, adaptability to several agro-ecological conditions, and nutritional and economic value.

The dramatic increase in the world’s population expected in this century will force a proportional increase in agricultural production in order to ensure the food supply. However, society is now demanding new, more sustainable, and environmentally friendly production methods. In order to achieve this sustainable increase, new biotechnological tools such as gene editing or synthetic biology will have to be used, leveraging the knowledge generated by researchers over decades. The soil microbiome is emerging as a powerful biotechnological tool. The beneficial microorganisms harboured in soils promote plant growth by supplying nutrients and producing hormones and secondary metabolites. Thus, these microorganisms will likely be able to help increase agricultural production in a sustainable way.

E8 is a famous root system in mathematics. Lisi claims in his paper “An Exceptionally Simple Theory of Everything” that there is a connection between the standard model of the elementary particles and this root system. He claims that standard model has the same structure as the root system E8. If this is true, there must be a mapping from the standard model to E8. This map must identify each elementary particle with an unique root of E8. Also the four charges (weak isospin, weak hypercharge, g3 and g8) of the standard model must have corresponding vectors in R8. These four charge vectors must have the property that taking the inner product of the charge vector and the root identified withan elementary particle, it would result in the charge of that particle. This is needed to guarantee that we have conservation of charge. In this paper we have shown that it is not possible to find a map with four charge vectors. This was done by studying root systems and how different root systems are present in E8 as sub root systems. We also proved that the intersection of E8 with the orthogonal complement of a charge, must be a root system. This limits the possibilities for the charge vectors. For these possible charges it has been checked whether there are enough roots for a given charge to identify the elementary particles. Since this was not the case, we concluded that no mapping with four charge vectors exists., Applied Mathematics | Applied Physics

The present study investigated how auxin concentration and the method of application affected the formation of adventitious roots in microshoots of chestnut (Castanea sativa) and oak (Quercus robur). The activity of two urea derivatives (2, 3-MDPU and 3, 4-MDPU) was also evaluated. Microshoots were derived from basal sprouts of two mature chestnut trees (P1 and P2) and one adult oak genotype (Sainza). In chestnut, rooting percentage was positively affected by auxin in a dose -dependent manner, particularly in shoots treated with the hormone for 24 h. The effect of auxin on rooting also differed depending on the application method. In shoots treated for 24 h, the highest concentration of auxin produced the healthiest rooted plantlets, in terms of the root system and shoot quality. By contrast, in shoots treated by the basal quick-dip method, the shoot quality was best at the lowest auxin concentration. The effect of urea derivatives on the root system depended on the species as well as on the auxin concentration and application period. Use of the MDPUs improved the root system architecture of auxintreated shoots by promoting lateral root development and triggering the synchronous initiation of root primordia at the base of the shoot. Shoot quality was also improved by MDPUs, which promoted resumption of growth and reduced shoot-tip necrosis.

From the economic perspective, the western corn rootworm (WCR), Diabrotica virgifera sp. virgifera (Col., Chrysomelidae), poses the gravest threat to the field maize production in Serbia. The purpose of this study is to examine the impact of WCR larvae on the morphology of maize characters during a low-level artificial egg infestation. A field experiment involving the Serbian cultivar 'NS-640' was carried ou Serbia, in 2016. In the experimental field, a total of 96 maize plants were selected, marked and arranged in 48 pairs. Each pair consisted of an infested plant (WCR eggs injected in the root zone) and an uninfested plant (distillate water injected in the root zone). The number of leaves, height and stem diameter of the plants observed were recorded. Root damage and root weight were measured and evaluated at the end of the trail. For the purpose of statistical analysis, the non-parametric Kruskal-Wallis one-way analysis of variance and a correlation matrix were used. The statistical analysis performed indicate a highly significant difference in the number of leaves and plant height between the infested and uninfested maize plants examined in July (the third field observation). During the last field inspection, significant differences were recorded only between the stem diameters of the infested and uninfested maize plants. A negative correlation was found to exist between the root damage and root weight of the plant pairs. There were positive correlations between the stem diameter, plant height and number of leaves of the infested plants, whereas positive correlations were found between the root damage and plant height of the uninfested plants.

Phosphate (Pi) is an essential nutrient for all organisms. Roots are underground organs, but the majority of the root biology studies have been done on root systems growing in the presence of light. Root illumination alters the Pi starvation response (PSR) at different intensities. Thus, we have analyzed morphological, transcriptional and physiological responses to Pi starvation in dark-grown roots. We have identified new genes and pathways regulated by Pi starvation that were not described previously. We also show that Pi-starved plants increase the cis-zeatin (cZ) : trans-zeatin (tZ) ratio. Transcriptomic analyses show that tZ preferentially represses cell cycle and PSR genes, whereas cZ induces genes involved in cell and root hair elongation and differentiation. In fact, cZ-treated seedlings show longer root system as well as longer root hairs compared with tZ-treated seedlings, increasing the total absorbing surface. Mutants with low cZ concentrations do not allocate free Pi in roots during Pi starvation. We propose that Pi-starved plants increase the cZ : tZ ratio to maintain basal cytokinin responses and allocate Pi in the root system to sustain its growth. Therefore, cZ acts as a PSR hormone that stimulates root and root hair elongation to enlarge the root absorbing surface and to increase Pi concentrations in roots.

В статті наведено результати досліджень із вивчення еколого-біологічних особливостей собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.) в умовах ботанічного розсадника Житомирського національного агроекологічного університету. На основі багаторічних досліджень вивчено вплив комплексного застосування регуляторів росту і мікродобрив на ріст та розвиток собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.), оцінено їх вплив на продуктивність і якість лікарської сировини в умовах Полісся України. На основі вивчення біологічних особливостей показано можливість вирощування нетрадиційної лікарської культури – собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.) – в умовах Полісся України для отримання стабільного врожаю і високого вмісту ефірної олії в надземній масі., The article presents the results of studies on the study of ecological and biological features of Leonurus quinquelobatus Gilib. under conditions of a botanical nursery of the Zhytomyr National Agroecological University. On the basis of many years of research, the influence of the complex application of growth regulators and microfertilizers on the growth and development of Leonurus quinquelobatus Gilib. has been studied, their influence on the productivity and quality of medicinal raw materials under the conditions of Polissіa of Ukraine has been evaluated. Cultivation of medicinal plants is one way of preserving the natural population of species, providing the required amount of raw materials for the needs of the pharmaceutical industry, replenishing the species diversity of medicinal plants through the use of rare and endangered species, and the introduction of promising species of adventitious species. The growth-stimulating activity of the Zircon growth regulator, which was included in the «State Catalog of Pesticides and Agrochemicals Permitted for Use on the Territory of Ukraine», was studied for the treatment of vegetative plants. On the basis of the study of biological characteristics, the possibility of growing an unconventional medicinal crop of Leonurus quinquelobatus Gilib. in the conditions of Polissіa of Ukraine is shown in order to obtain a stable crop and high content of essential oils in the aboveground mass. Increasing the yield of biomass of Leonurus quinquelobatus Gilib. and improving the quality of the raw material provides a two-fold application of the Zircon growth regulator at a rate of consumption of 35 milliliter per hectare (first year of vegetation) + 50 milliliter per hectare (from the second year of vegetation) or the combined use of zircon with a rate of consumption 35 milliliter per hectare (the first year of vegetation) and microfertilizer Ferovit and Citovit with a rate of consumption of 400 ml/ha in the second year of vegetation., В статье приведены результаты исследований по изучению эколого-биологических особенностей пустырника сердечного (Leonurus quinquelobatus Gilib.) в условиях ботанического питомника Житомирского национального агроэкологического университета. На основе многолетних исследований изучено влияние комплексного применения регуляторов роста и микроудобрений на рост и развитие пустырника сердечного (Leonurus quinquelobatus Gilib.), оценено их влияние на урожайность и качество лекарственного сырья в условиях Полесья Украины. На основе изучения биологических особенностей показана возможность выращивания нетрадиционной лекарственной культуры – пустырник сердечный (Leonurus quinquelobatus Gilib.) условиях Полесья Украины для получения стабильного урожая и высокого содержания эфирного масла в надземной массе.

В статті наведено результати досліджень із вивчення еколого-біологічних особливостей собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.) в умовах ботанічного розсадника Житомирського національного агроекологічного університету. На основі багаторічних досліджень вивчено вплив комплексного застосування регуляторів росту і мікродобрив на ріст та розвиток собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.), оцінено їх вплив на продуктивність і якість лікарської сировини в умовах Полісся України. На основі вивчення біологічних особливостей показано можливість вирощування нетрадиційної лікарської культури – собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.) – в умовах Полісся України для отримання стабільного врожаю і високого вмісту ефірної олії в надземній масі., The article presents the results of studies on the study of ecological and biological features of Leonurus quinquelobatus Gilib. under conditions of a botanical nursery of the Zhytomyr National Agroecological University. On the basis of many years of research, the influence of the complex application of growth regulators and microfertilizers on the growth and development of Leonurus quinquelobatus Gilib. has been studied, their influence on the productivity and quality of medicinal raw materials under the conditions of Polissіa of Ukraine has been evaluated. Cultivation of medicinal plants is one way of preserving the natural population of species, providing the required amount of raw materials for the needs of the pharmaceutical industry, replenishing the species diversity of medicinal plants through the use of rare and endangered species, and the introduction of promising species of adventitious species. The growth-stimulating activity of the Zircon growth regulator, which was included in the «State Catalog of Pesticides and Agrochemicals Permitted for Use on the Territory of Ukraine», was studied for the treatment of vegetative plants. On the basis of the study of biological characteristics, the possibility of growing an unconventional medicinal crop of Leonurus quinquelobatus Gilib. in the conditions of Polissіa of Ukraine is shown in order to obtain a stable crop and high content of essential oils in the aboveground mass. Increasing the yield of biomass of Leonurus quinquelobatus Gilib. and improving the quality of the raw material provides a two-fold application of the Zircon growth regulator at a rate of consumption of 35 milliliter per hectare (first year of vegetation) + 50 milliliter per hectare (from the second year of vegetation) or the combined use of zircon with a rate of consumption 35 milliliter per hectare (the first year of vegetation) and microfertilizer Ferovit and Citovit with a rate of consumption of 400 ml/ha in the second year of vegetation., В статье приведены результаты исследований по изучению эколого-биологических особенностей пустырника сердечного (Leonurus quinquelobatus Gilib.) в условиях ботанического питомника Житомирского национального агроэкологического университета. На основе многолетних исследований изучено влияние комплексного применения регуляторов роста и микроудобрений на рост и развитие пустырника сердечного (Leonurus quinquelobatus Gilib.), оценено их влияние на урожайность и качество лекарственного сырья в условиях Полесья Украины. На основе изучения биологических особенностей показана возможность выращивания нетрадиционной лекарственной культуры – пустырник сердечный (Leonurus quinquelobatus Gilib.) условиях Полесья Украины для получения стабильного урожая и высокого содержания эфирного масла в надземной массе.

В статті наведено результати досліджень із вивчення еколого-біологічних особливостей собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.) в умовах ботанічного розсадника Житомирського національного агроекологічного університету. На основі багаторічних досліджень вивчено вплив комплексного застосування регуляторів росту і мікродобрив на ріст та розвиток собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.), оцінено їх вплив на продуктивність і якість лікарської сировини в умовах Полісся України. На основі вивчення біологічних особливостей показано можливість вирощування нетрадиційної лікарської культури – собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.) – в умовах Полісся України для отримання стабільного врожаю і високого вмісту ефірної олії в надземній масі., The article presents the results of studies on the study of ecological and biological features of Leonurus quinquelobatus Gilib. under conditions of a botanical nursery of the Zhytomyr National Agroecological University. On the basis of many years of research, the influence of the complex application of growth regulators and microfertilizers on the growth and development of Leonurus quinquelobatus Gilib. has been studied, their influence on the productivity and quality of medicinal raw materials under the conditions of Polissіa of Ukraine has been evaluated. Cultivation of medicinal plants is one way of preserving the natural population of species, providing the required amount of raw materials for the needs of the pharmaceutical industry, replenishing the species diversity of medicinal plants through the use of rare and endangered species, and the introduction of promising species of adventitious species. The growth-stimulating activity of the Zircon growth regulator, which was included in the «State Catalog of Pesticides and Agrochemicals Permitted for Use on the Territory of Ukraine», was studied for the treatment of vegetative plants. On the basis of the study of biological characteristics, the possibility of growing an unconventional medicinal crop of Leonurus quinquelobatus Gilib. in the conditions of Polissіa of Ukraine is shown in order to obtain a stable crop and high content of essential oils in the aboveground mass. Increasing the yield of biomass of Leonurus quinquelobatus Gilib. and improving the quality of the raw material provides a two-fold application of the Zircon growth regulator at a rate of consumption of 35 milliliter per hectare (first year of vegetation) + 50 milliliter per hectare (from the second year of vegetation) or the combined use of zircon with a rate of consumption 35 milliliter per hectare (the first year of vegetation) and microfertilizer Ferovit and Citovit with a rate of consumption of 400 ml/ha in the second year of vegetation., В статье приведены результаты исследований по изучению эколого-биологических особенностей пустырника сердечного (Leonurus quinquelobatus Gilib.) в условиях ботанического питомника Житомирского национального агроэкологического университета. На основе многолетних исследований изучено влияние комплексного применения регуляторов роста и микроудобрений на рост и развитие пустырника сердечного (Leonurus quinquelobatus Gilib.), оценено их влияние на урожайность и качество лекарственного сырья в условиях Полесья Украины. На основе изучения биологических особенностей показана возможность выращивания нетрадиционной лекарственной культуры – пустырник сердечный (Leonurus quinquelobatus Gilib.) условиях Полесья Украины для получения стабильного урожая и высокого содержания эфирного масла в надземной массе.

В статті наведено результати досліджень із вивчення еколого-біологічних особливостей собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.) в умовах ботанічного розсадника Житомирського національного агроекологічного університету. На основі багаторічних досліджень вивчено вплив комплексного застосування регуляторів росту і мікродобрив на ріст та розвиток собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.), оцінено їх вплив на продуктивність і якість лікарської сировини в умовах Полісся України. На основі вивчення біологічних особливостей показано можливість вирощування нетрадиційної лікарської культури – собачої кропиви п’ятилопатевої (Leonurus quinquelobatus Gilib.) – в умовах Полісся України для отримання стабільного врожаю і високого вмісту ефірної олії в надземній масі., The article presents the results of studies on the study of ecological and biological features of Leonurus quinquelobatus Gilib. under conditions of a botanical nursery of the Zhytomyr National Agroecological University. On the basis of many years of research, the influence of the complex application of growth regulators and microfertilizers on the growth and development of Leonurus quinquelobatus Gilib. has been studied, their influence on the productivity and quality of medicinal raw materials under the conditions of Polissіa of Ukraine has been evaluated. Cultivation of medicinal plants is one way of preserving the natural population of species, providing the required amount of raw materials for the needs of the pharmaceutical industry, replenishing the species diversity of medicinal plants through the use of rare and endangered species, and the introduction of promising species of adventitious species. The growth-stimulating activity of the Zircon growth regulator, which was included in the «State Catalog of Pesticides and Agrochemicals Permitted for Use on the Territory of Ukraine», was studied for the treatment of vegetative plants. On the basis of the study of biological characteristics, the possibility of growing an unconventional medicinal crop of Leonurus quinquelobatus Gilib. in the conditions of Polissіa of Ukraine is shown in order to obtain a stable crop and high content of essential oils in the aboveground mass. Increasing the yield of biomass of Leonurus quinquelobatus Gilib. and improving the quality of the raw material provides a two-fold application of the Zircon growth regulator at a rate of consumption of 35 milliliter per hectare (first year of vegetation) + 50 milliliter per hectare (from the second year of vegetation) or the combined use of zircon with a rate of consumption 35 milliliter per hectare (the first year of vegetation) and microfertilizer Ferovit and Citovit with a rate of consumption of 400 ml/ha in the second year of vegetation., В статье приведены результаты исследований по изучению эколого-биологических особенностей пустырника сердечного (Leonurus quinquelobatus Gilib.) в условиях ботанического питомника Житомирского национального агроэкологического университета. На основе многолетних исследований изучено влияние комплексного применения регуляторов роста и микроудобрений на рост и развитие пустырника сердечного (Leonurus quinquelobatus Gilib.), оценено их влияние на урожайность и качество лекарственного сырья в условиях Полесья Украины. На основе изучения биологических особенностей показана возможность выращивания нетрадиционной лекарственной культуры – пустырник сердечный (Leonurus quinquelobatus Gilib.) условиях Полесья Украины для получения стабильного урожая и высокого содержания эфирного масла в надземной массе.

El género Capsicum sp. es uno de los cultivos hortícolas mas importantes y extendidos a nivel mundial. El auge de manejos agrarios distintos al convencional, como es el caso del ecológico, hace necesaria la investigación de la interacción de los cultivos hortícolas con los distintos sistemas de cultivo utilizados. Por ello, en el presente trabajo se ha procedido a realizar un análisis fenotípico del sistema radicular de 19 genotipos pertenecientes a varias especies cultivadas de este género bajo dos regímenes de cultivo: convencional y ecológico. Para su fenotipado, se utilizaron dos plataformas diferentes disponibles en el mercado. Los resultados obtenidos, mostraron la gran diversidad intraespecífica e interespecífica del sistema radicular existente en este género, así como su interacción con el sistema de cultivo utilizado. Estas diferencias fueron constatables en los distintos caracteres morfológicos medidos, lo cual muestra la idoneidad de cada genotipo para cada sistema de cultivo., The genus Capsicum sp. is one of the most important and spread vegetables all over the world. The rise of different agricultural production systems to conventional, as the organic system is, make necessary the research about the interaction of these crops with the agricultural production systems used. For that, in the present study we have proceeded to analyze phenotypically the root systems of 19 genotypes from different cultivated species of this genus under two different agricultural production systems: Conventional and organic. We have used two commercial phenotyping platforms to achieve that: Pepper Shovelomics Scoreboard & WinRhizo. Our results, shown the huge intraspecific and interspecific diversity existent on the root system of this genus, as well as its interaction with the agricultural production system used. These differences were significant for the different morphological traits measured, which shows the suitability of each genotype for each agricultural production system.

Existing literature about maize root system hydraulic and architectural properties is abundant and can serve as input for contrasted root system hydraulic architecture generation tools. Therefore observations of root hydraulic and architectural phenes in field and/or laboratory experiments must be first converted into parameters for feeding root growth model and water flow algorithms. MARSHAL aims at gathering the existing information about the maize plant and at making it available for the community. Existing maize root system architecture parameterizations as well as measured hydraulic functions were gathered in a common database and linked with the state-of-art model of the water transfer in the soil-plant-atmosphere continuum. MARSHAL is as an online and flexible tool that generates contrasted root system hydraulic architectures using this database, calculates the water flow within the root system under user-provided boundary conditions (transpiration and soil water potential distribution) and calculates plant-scale macroscopic parameters. The generated root systems hydraulic architectures can be saved in common formats such as RSML to be easily imported in other models. Finally, MARSHAL is coupled with sensitivity and optimization algorithms in order to investigate the sensitive input parameters for a used-defined objective function or to provide an optimal set of parameters that minimizes an error function, alongside with parameter uncertainty. As illustration of the model potentiality, we used MARSHAL to generate maize contrasted hydraulic architectures and we compared them with plant-scale observations of both architecture (root length density profile field measurements) and hydraulics (root system conductance measurements). The macroscopic parameters could be easily fitted with the model and the observed local variability of root phenes determined. The hydraulic architectures were then used as contrasted genotypes in a water flow model of the soil-plant-atm

Despite its importance for understanding transpiration regulation and soil water fluxes, characterizing the distribution of root water uptake and its evolution over time is still challenging. Measurements of root hydraulic properties are feasible with standard techniques (root pressure probe, pressure chamber, high pressure flow meter. . . ) but these methods are destructive and time consuming. Moreover, the evolution of root properties with time is hardly achievable. In this study, we combined experiment and modelling to characterize in situ plant root hydraulic properties. We monitored for seven days the leaching of a tracer through a column with a growing root system of a white lupine plant. After six days, the irrigation of the tracer was stopped to enhance the tracer accumulation around roots. We used Magnetic Resonance Imaging (MRI) to get daily three-dimensional root architecture and solute distribution. Then, the plant-soil system was modelled with R-SWMS (Javaux et al, 2008), a 3D model that provides water and tracer dynamics in the soil-plant system. An optimisation was performed to retrieve the root hydraulic parameters during the solute accumulation stage. R-SWMS was proven to be a convenient tool for modelling 3D tracer dynamic in a planted soil column. Furthermore, data obtained by MRI (i.e. the 3D solute accumulation around roots) was shown to be informative enough to optimize root hydraulic properties and their evolution over time. In conclusion, the combination of experiment and modelling seems to be needed and useful for characterizing root hydraulic properties in 3D systems.

Existing literature about maize root system hydraulic and architectural properties is abundant and can serve as input for contrasted root system hydraulic architecture generation tools. Therefore observations of root hydraulic and architectural phenes in and/or laboratory experiments must be first converted into parameters for feeding root growth model and water flow algorithms. MARSHAL aims at gathering the existing information about the maize plant and at making it available for the community. Existing maize root system architecture parameterizations as well as measured hydraulic functions were gathered in a common database and linked with the state-of-art model of the water transfer in the soil-plantatmosphere continuum. MARSHAL is as an online and flexible tool that generates contrasted root system hydraulic architectures using this database, calculates the water flow within the root system under user-provided boundary conditions (transpiration and soil water potential distribution) and calculates plant-scale macroscopic parameters. The generated root systems hydraulic architectures can be saved in common formats such as RSML to be easily imported in other models. Finally, MARSHAL is coupled with sensitivity and optimization algorithms in order to investigate the sensitive input parameters for a used-defined! objective function or to provide an optimal set of parameters that minimizes an error function, alongside with parameter uncertainty. As illustration of the model potentiality, we used MARSHAL to generate maize contrasted hydraulic architectures and we compared them with plant-scale observations of both architecture (root length density profile field measurements) and hydraulics (root system conductance measurements). The macroscopic parameters could be easily fitted with the model and the observed local variability of root phenes determined. The hydraulic architectures were then used as contrasted genotypes in a water flow model of the soil-plant-atmospher

The application of geophysical methods to root investigation is increasing in recent years because of the limitations associated with the use of traditional methods (root excavation, monoliths, minirhizotron etc.). Point sampling is only partially satisfactory as a result of the spatial variability and dynamics of the roots zone. Geophysical methods address these limitations by offering high resolution and non-invasive approaches to root investigation due to their ability to infer properties and structures of the subsurface as well as the flow and transport processes occurring in the shallow subsurface, at various spatial scales. Recent studies (Weigand and Kemna 2017; Mary et al. 2017) have reported a low frequency polarization of root systems and have shown that SIP/EIT holds a promising future for root system characterization. Despite these significant improvements, there is still a knowledge gap regarding the electrical response of fine roots at the segment scale which is essential to enable us to account for the effect of roots in the estimation of soil moisture content of rooted soils or to exploit electromagnetic methods to characterize certain root system characteristics. We hereby propose a method for the characterization of electrical properties of single root segments of various plants resulting from an externally applied electrical field. A sample holder was designed and tested on ideal resistors and root segments, and was found to be suitable for assessing the electrical properties of root segments of 1-5 cm length and 2 mm diameter at a frequency range of 1Hz – 45 KHz. The system was then used to obtain complex electrical responses of the root segments of the target plants in the laboratory. This enabled us to study different root properties and their effects on the root electrical signals. Our results suggest that fine roots could be differentiated from soils because they show lower resistivity and polarizes more than soils.

The magnitude and distribution of root water uptake is controlled by the distribution of soil, rhizosphere and root hydraulic properties and how these are connected to each other. Therefore, estimating the ability of a root system to extract water depends not only on the root system architecture and hydraulics but also on the environmental conditions. While experimental tools exist to characterize soil, rhizosphere and root segment hydraulic properties, how the combination of soil/plant local properties relate to the whole plant hydraulic behavior is still an open question. Today, modeling tools exist that simulate the soil-root system hydraulics at local and plant scales. Based on physical laws these multiscale models integrate the impact of the plant regulation on internal resistances and the control of the soil and of the rhizosphere on water stream. They have also been used to estimate root hydraulic properties by inverse modeling. Yet, simplified, upscaled models are needed, which estimate plant behavior at lower computational costs. Here, we present an analytic pipeline based on mathematical models, which allow one to estimate root scale macroscopic properties based on specific root and rhizosphere traits, without the need of solving of the full water equations in a 3D root system. This allow us to quantitatively estimate the sensitivity of root system conductance to local traits. It can also be used to investigate how combinations of plant traits will lead to conservative or risky water uptake strategies. Finally, we can identify optimal strategies as a function of environmental constraints. These tools allow us to define the concept of “eco-ideotypes”, i.e. ideal combination of local root traits that optimize their water capture over their crop cycle in a particular environment. These new tools were compared to a FSPM model to validate their performance.

We prove a simplicity criterion for certain twin tree lattices. It applies to all rank two Kac–Moody groups over finite fields with non-trivial commutation relations, thereby yielding examples of simple non-uniform lattices in the product of two trees.