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Non-structural carbohydrates in woody plants compared among laboratories

Non-structural carbohydrates in woody plants compared among laboratories

Many carbohydrates can comprise NSC such as monosaccha- rides (glucose and fructose), disaccharides (sucrose), polysac- charides (starch and fructans), oligosaccharides (raffinose) and sugar alcohols (inositol, sorbitol and mannitol) ( Rastall 1990 , Stick and Williams 2010 ). Sucrose, fructose and glucose are gen- erally, but not always, the predominant soluble sugars, and starch is the pivotal non-soluble longer-term storage compound ( Mooney 1972 , Chapin et al. 1990 ); many studies focus on these four carbohydrates while measuring plant NSC. The diver- sity of carbohydrates and matrices (tissue structural and bio- chemical characteristics), and the search for reliable and inexpensive methods that can be used for the large number of samples in environmental plant physiology studies, has led to the development of many analytical methods to determine the iden- tity and amount of carbohydrates in plant tissue (Table 1 , Table S1 available as Supplementary Data at Tree Physiology Online; Non-structural carbohydrates (NSC) in plant tissue are frequently quantified to make inferences about plant responses to envi- ronmental conditions. Laboratories publishing estimates of NSC of woody plants use many different methods to evaluate NSC. We asked whether NSC estimates in the recent literature could be quantitatively compared among studies. We also asked whether any differences among laboratories were related to the extraction and quantification methods used to determine starch and sugar concentrations. These questions were addressed by sending sub-samples collected from five woody plant tissues, which varied in NSC content and chemical composition, to 29 laboratories. Each laboratory analyzed the samples with their laboratory-specific protocols, based on recent publications, to determine concentrations of soluble sugars, starch and their sum, total NSC. Labora- tory estimates differed substantially for all samples. For example, estimates for Eucalyptus globulus leaves (EGL) varied from 23 to 116 (mean = 56) mg g −1 for soluble sugars, 6–533 (mean = 94) mg g −1 for starch and 53–649 (mean = 153) mg g −1 for total
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Comparison of explant responses treated with leachate and leonardite sources of humic substances during in vitro rooting of woody plants.

Comparison of explant responses treated with leachate and leonardite sources of humic substances during in vitro rooting of woody plants.

3.2. HS effect on root growth and development Root development is an important requirement for plants adaptation and survival in difficult conditions. It is the first plant organ targeted by the soil HS widely reported as complex organic materials that influence root growth and architecture (Muscolo et al. 2013). HS have long been known to improve root growth and development in several plant species through the stimulation of root elongation, root hair and lateral root production (Zandonadi et al. 2007; Canellas et al. 2002; 2009). The biological activity evaluation is generally present in two forms, the quantification of the beneficial effect of the humic substances onto the plant, and the principle of this beneficial effect.
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Jr-ZFP2, encoding a Cys2/His2-type transcription factor, is involved in the early stages of the mechano-perception pathway and specifically expressed in mechanically stimulated tissues in woody plants

Jr-ZFP2, encoding a Cys2/His2-type transcription factor, is involved in the early stages of the mechano-perception pathway and specifically expressed in mechanically stimulated tissues in woody plants

Inhibition of ethylene perception blocks the upregulation of the petunia C 2 H 2 zinc finger ZPT2-2 expression in petals after pollination, suggesting that ethylene acts as an inducing signal in this regulation system (Van der Krol et al. 1999). However, the incubation of whole plants or flowers with exogenous ethylene did not induce the expression of ZPT2-2; ethylene is thus not sufficient for ZPT2-2 induction. All these experiments confirmed that these C2H2-type zinc-finger transcription factors are important in the signal- ling pathway for mechanical stimulus. The genes they control, however, are not known. Bioinformatical analyses of the sequence suggest that Jr-ZFP2 could act as an active repressor. Lee et al. (2005) identified 171 Arabidopsis genes through microarray analysis, which had reduced expression in rosette leaves 30 min after bending. It will be interesting to determine if part of these genes could be downregulated by orthologs of Jr-ZFP2.
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Woody plant cover estimation in drylands from Earth Observation based seasonal metrics

Woody plant cover estimation in drylands from Earth Observation based seasonal metrics

summarized in Table 1 and illustrated in Fig. 4 . The values between the end of the growing season (EOS) and the start of the next growing sea- son (SOS) were integrated to a dry season integral (DSINT) by subtracting the small integral (SINT) from the annual integral. Thus the DSINT also includes the rainy season values below the base level (BASE) ( Fig. 4 ), considering that annual herbaceous spontaneous spe- cies are starting from zero green, while woody plants have already put leaves explaining the level of the BASE being above zero before the first rainfalls at the SOS. The onset of the rainy and dry season is estimat- ed from crossing a de fined percentage threshold of the annual ampli- tude (AMP) value. Whereas the standard value of 20% has proven to deliver robust results for the SOS ( Horion et al., 2014 ), the EOS is in flu- enced by several factors and needs to be selected with caution. In addi- tion to woody vegetation, the presence of crops can impact the early dry season signal, since some crops (e.g. millet) remain greener 2 –4 weeks longer than the annual grasses. To better separate the core rainy season from in fluences, the threshold for the EOS was set to 80% of the ampli- tude ( Fig. 4 ). As we expect to capture the contribution of woody plants with the DSINT variable, an integration period starting approximately mid-October is also preferable since some woody plant populations are dominated by short deciduous species (e.g. Acacia seyal) shedding their leaves in the early dry season ( Fig. 3 ). To account for unreliable values extracted in areas of very low vegetation (as no distinct seasonal curve is present for such areas), the woody cover of all pixels with a mean maximum annual FAPAR b0.05 and a stddev b0.02 was set to 0.5% (the total absence of shrubs is unlikely at 1 km scale). Wetlands and irrigated areas were masked by excluding areas of high FAPAR values N0.2 between late November and February, as only wetlands and irrigated croplands stay dark green during this time.
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Physics of rapid movements in plants

Physics of rapid movements in plants

in animal muscles to deform and generate movement. However, the stiff wall allows plant cells to sustain a very high internal water pressure ("turgor pressure"), typically 4-8 bars and possibly up to 40 bars in special cells. Water in plants may also undergo negative pressures, thanks to the cohesive forces between water molecules, resulting in an inward pulling on walls; the mature cell wall of woody plants avoids damaging of structure even at the highest negative pressures (~ -100 bars).

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The woody planet: from past triumph to manmade decline

The woody planet: from past triumph to manmade decline

2. The Origin of Woody Plants The earliest land plants had no vascular tissue and used ectohydric water transport by capillarity along their external surface [ 6 ]. Woodiness, which allowed endohydric, internal water transport, appeared approximately 100 million years after the conquering of land by plants [ 6 – 8 ]. The oldest wood tissue is derived from the Early Devonian, ca. 400 Mya [ 9 ]. These early woody plants were very small and used their woody structures as plumbing systems for taking up water rather than providing mechanical support [ 9 ]. Large woody plants evolved secondarily by taking advantage of the newly evolved support. Once woodiness evolved, however, the evolution of large woody trunks (so-called hyperstele) was extremely rapid [ 6 ]. In fact, it happened almost immediately, since tree habit and large trunks were already present between 385 and 390 Mya, mainly in progymnosperms [ 10 ] but also in cladoxylopsids [ 11 ]. Moreover, fossil records suggest that these organisms formed very early complex and dense forest ecosystems. These large woody organisms changed the evolutionary dynamics of terrestrial habitats, and their decaying branches, leaves and trunks significantly altered geochemical cycles all over the Earth [ 10 , 11 ]. Some other plant groups (e.g., arborescent lycophytes, horsetails and ferns) also evolved strategies to form tree-like organisms [ 6 ]. However, although they had some secondary xylem, their stems were determinate and short-lived, and thus, they should be denominated as “giant herbs” rather than true woody species or trees [ 6 ].
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Hardwood tree genomics: unlocking woody plant biology

Hardwood tree genomics: unlocking woody plant biology

Department of Ecosystem Science and Management, Pennsylvania State University, University Park, PA, United States, 15 Department of Entomology, Plant Pathology and Weed Science, New Mexico State University, Las Cruces, NM, United States, 16 The American Chestnut Foundation, Asheville, NC, United States Woody perennial angiosperms (i.e., hardwood trees) are polyphyletic in origin and occur in most angiosperm orders. Despite their independent origins, hardwoods have shared physiological, anatomical, and life history traits distinct from their herbaceous relatives. New high-throughput DNA sequencing platforms have provided access to numerous woody plant genomes beyond the early reference genomes of Populus and Eucalyptus, references that now include willow and oak, with pecan and chestnut soon to follow. Genomic studies within these diverse and undomesticated species have successfully linked genes to ecological, physiological, and developmental traits directly. Moreover, comparative genomic approaches are providing insights into speciation events while large-scale DNA resequencing of native collections is identifying population-level genetic diversity responsible for variation in key woody plant biology across and within species. Current research is focused on developing genomic prediction models for breeding, defining speciation and local adaptation, detecting and characterizing somatic mutations, revealing the mechanisms of gender determination and flowering, and application of systems biology approaches to model complex regulatory networks underlying quantitative traits. Emerging technologies such as single-molecule, long-read sequencing is being employed as additional woody plant species, and genotypes within species, are sequenced, thus enabling a comparative (“evo-devo”) approach to understanding the unique biology of large woody plants. Resource availability, current genomic and genetic applications, new discoveries and predicted future developments are illustrated and discussed for poplar, eucalyptus, willow, oak, chestnut, and pecan.
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Fire regimes and variability in aboveground woody biomass in miombo woodland

Fire regimes and variability in aboveground woody biomass in miombo woodland

5. Conclusions Fire has a large impact on aboveground woody biomass and vegetation structure in miombo woodland. Fire retards the development of trees to maturity by removing aerial biomass and reducing tree size. The severity of fire disturbance to woody plants varies significantly with the fire regime, i.e., with fire return inter- val and fire intensity. A shorter fire return interval and higher fire intensity results in a greater reduction of aboveground woody biomass by reducing the mean tree size within the population. Fires in miombo woodland are mostly human induced, and the fire return interval is effectively a management tool. How- ever, fire intensity depends on the amount of grass fuel available for combustion and on the season. The current practice of frequent burning needs to be replaced with more rigorous fire control if today’s miombo woodland ecosystem is to be sustained. Available data suggest that elevated CO 2 concentrations, warm-
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Comportement de plants de vigne issus de microgreffage d'apex

Comportement de plants de vigne issus de microgreffage d'apex

Trois cubes dépourvus d'ex plants, par génotype et par milieu, ont été maintenus dans les mêmes conditions expérimentales, dans le but d 'év aluer les variatio ns [r]

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Multiobjective scheduling for semiconductor manufacturing plants

Multiobjective scheduling for semiconductor manufacturing plants

Six criteria related to the equipments (FAU: facility average utilization) and the products (ACT: average cycle time, SD: standard deviation of ACT, AWT: average waiting time, NB: number[r]

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The Woody-Preferential Gene EgMYB88 Regulates the Biosynthesis of Phenylpropanoid-Derived Compounds in Wood

The Woody-Preferential Gene EgMYB88 Regulates the Biosynthesis of Phenylpropanoid-Derived Compounds in Wood

Paul Sabatier, Toulouse, France, 2 Department of Plant Physiology, Umeå University, Umeå, Sweden, 3 “Agronomie et Environnement” Nancy-Colmar, Institut National de la Recherche Agronomique, Université de Lorraine UMR1121, Vandœuvre-lès-Nancy, France Comparative phylogenetic analyses of the R2R3-MYB transcription factor family revealed that five subgroups were preferentially found in woody species and were totally absent from Brassicaceae and monocots ( Soler et al., 2015 ). Here, we analyzed one of these subgroups (WPS-I) for which no gene had been yet characterized. Most Eucalyptus members of WPS-I are preferentially expressed in the vascular cambium, the secondary meristem responsible for tree radial growth. We focused on EgMYB88, which is the most specifically and highly expressed in vascular tissues, and showed that it behaves as a transcriptional activator in yeast. Then, we functionally characterized EgMYB88 in both transgenic Arabidopsis and poplar plants overexpressing either the native or the dominant repression form (fused to the Ethylene-responsive element binding factor-associated Amphiphilic Repression motif, EAR). The transgenic Arabidopsis lines had no phenotype whereas the poplar lines overexpressing EgMYB88 exhibited a substantial increase in the levels of the flavonoid catechin and of some salicinoid phenolic glycosides (salicortin, salireposide, and tremulacin), in agreement with the increase of the transcript levels of landmark biosynthetic genes. A change in the lignin structure (increase in the syringyl vs. guaiacyl, S/G ratio) was also observed. Poplar lines overexpressing the EgMYB88 dominant repression form did not show a strict opposite phenotype. The level of catechin was reduced, but the levels of the salicinoid phenolic glycosides and the S/G ratio remained unchanged. In addition, they showed a reduction in soluble oligolignols containing sinapyl p-hydroxybenzoate accompanied by a mild reduction of the insoluble lignin content. Altogether, these results suggest that EgMYB88, and more largely members of the WPS-I group, could control in cambium and in the first layers of differentiating xylem the biosynthesis of some phenylpropanoid-derived secondary metabolites including lignin.
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Autophagy and Nutrients Management in Plants

Autophagy and Nutrients Management in Plants

2. Molecular Machinery of Macro-Autophagy in Plants Professor Yoshinori Ohsumi was awarded the Nobel Prize for Physiology or Medicine in 2016 for his discovery of the molecular basis of macro-autophagy (hereafter referred to as autophagy). Together with colleagues, he identified several ATG genes that participate in autophagic processes by yeast forward genetic experiments [17]. To date, more than 40 ATG genes have been identified in yeast, and the orthologs for most of them have been found in different plant species such as Arabidopsis, rice, wheat, maize, tobacco, barley, foxtail millet, and apple [12,13,18–23]. The functional analysis of these proteins reveals a canonical route for autophagy. Basically, the process of autophagy consists of the induction of the nucleation of pre-autophagosomal structures, membrane elongation, phagophore expansion, and then closure, trafficking, and delivery of the autophagosome to the vacuole, and finally breakdown of the autophagic membrane and its contents by hydrolases into the vacuole (Figure 1) [2]. The ATG1 and ATG13 proteins, together with two accessory proteins, ATG11 and ATG101, assemble into an active ATG1-ATG13 complex [24] that promotes the nucleation and expansion of a cup-shaped double-membrane (phagophore), which is thought to originate from the endoplasmic reticulum (ER) [25–27]. The transmembrane protein ATG9 recruits lipids for phagophore elongation, ATG2, and ATG18 proteins facilitate ATG9 cycling [16,26]. Another step involves phagophore decoration with phosphatidylinositol-3-phosphate (PI3P) generated by a class III complex containing the phosphatidylinositol-3-kinase (PI3K) encoded by vacuolar protein sorting 34 (VPS34), along with three core accessory subunits, ATG6, VPS38 or ATG14, and VPS15 [28,29]. Expansion and closure of the phagophore membranes require two ubiquitination-like systems. Ubiquitin-fold protein ATG8 is initially processed by a cysteine protease ATG4 to expose a
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Enhancing agroecosystem productivity with woody perennials in semi-arid West Africa. A meta-analysis

Enhancing agroecosystem productivity with woody perennials in semi-arid West Africa. A meta-analysis

3.1.2 Soil carbon Higher total soil C content (+ 20 to 75%) under canopies of woody perennials (Fig. 7 a) is normally ascribed to litter depo- sition and sediment trapping. “Fertility” islands under peren- nial shrub canopies are also linked to fine root decay (Manlay et al. 2004 ) and effective entrapment of wind-blown sedi- ments (Wezel et al. 2000 ; Leenders et al. 2007 ), with sediment capture efficiency as a function of shrub density and canopy size (Mudrak et al. 2014 ). This effect may also be related to the presence (and decomposition) of herbaceous plants whose growth is favoured underneath the shrub crown (Yélémou et al. 2012 ). The presence of perennial species in agricultural fields may also create a microclimate due to shading and de- position of above- and belowground organic material, resulting in pedospheres with increased capacity for C seques- tration. Measurements of soil δ 13 C isotopic content in Burkina Faso showed that soil C in the vicinity of tree trunks was mainly from tree origin (C 3 ) and that C 4 -derived soil C (from
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Comparison of large woody debris prototypes in a large scale non-flume physical model

Comparison of large woody debris prototypes in a large scale non-flume physical model

2 Ocean, Coastal and River Engineering, National Research Council of Canada, Ottawa, Ontario Canada Abstract. Due to excessive rainfall in June of 2013, several rivers located in and near the City of Calgary, Canada experienced significant flooding events. These events caused severe damage to infrastructure throughout the city, precipitating a renewed interest in flood control and mitigation strategies for the area. A major potential strategy involves partial diversion of Elbow River flood water to the proposed Springbank Off-Stream Storage Reservoir. A large scale physical model study was conducted to optimize and validate the design of a portion of the new project. The goals of the physical model were to investigate diversion system behaviors such as flow rates, water levels, sediment transport and, debris accumulation, and optimize the design of new flow control structures to be constructed on the Elbow River. In order to accurately represent the behavior of debris within the system due to flooding, large woody debris created from natural sources was utilized in the physical model and its performance was compared to that of debris of the same size fabricated from pressed cylindrical wood dowels. In addition to comparing the performance of these two debris types, the impact of root wads on debris damming was also investigated. Significant differences in damming behavior was shown to exist between the natural debris and the fabricated debris, while the impact of root wad on damming affected the dam structure and formation. The results of this experiment indicate that natural debris is preferred for studies involving debris accumulation.
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Decadal biomass increment in early secondary succession woody ecosystems is increased by CO2 enrichment

Decadal biomass increment in early secondary succession woody ecosystems is increased by CO2 enrichment

At Rhinelander, the observed biomass retention rate was lower than calculated (0.64 versus 0.73) indicating that a process other than allocation was likely increasing vegetation turnover[r]

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The role of native woody species in the restoration of Campos Rupestres in quarries

The role of native woody species in the restoration of Campos Rupestres in quarries

species, even if they did not significantly influence soil properties and understorey plant 414.. composition, affected significantly their immediate vicinity modifying soil[r]

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Diversity of woody plant seedling banks under closed canopy in fragmented coppice forests

Diversity of woody plant seedling banks under closed canopy in fragmented coppice forests

This study aims: (i) to identify which woody species were able to establish themselves under closed canopy of coppice forests; and (ii) to evaluate the influences of canopy compo- sition[r]

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Responses to Telomere Erosion in Plants

Responses to Telomere Erosion in Plants

by the telomerase, a specialised reverse transcriptase that extends chromosome 39 DNA ends by adding repeats of telomeric DNA using its RNA subunit as template. In the absence of telomerase, telomere erosion acts as a biological ‘‘clock’’, limiting the proliferative potential of cells and playing a major role in cellular ageing and protection against cancer [21]. Absence of the telomerase reverse transcriptase (TERT) in Arabidopsis leads to the progressive erosion of telomeric DNA sequences, which, in turn, results in telomere uncapping and increasingly severe genetic instability accompanied by visible developmental defects and reduced fertility in the fourth or fifth mutant generations. These become progressively more severe in succeeding generations, resulting in problems in growth and development and in complete sterility by the tenth or eleventh generation [22]. The effects of telomere erosion in mammals are also dramatic. Mice deficient for TERT exhibit reduced fertility and progressive defects in highly proliferative organs in the 3 rd generation and embryonic developmental defects and sterility in the 6 th generation [23–26]. The most striking difference is that plants harbouring short telomeres have an extended life span and remain metabolically active while telomere dysfunction in mice induces metabolic and mitochondrial compromise [27].
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Annotated bibliography on cold storage plants

Annotated bibliography on cold storage plants

L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB.. Bibliograph[r]

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When plants and plastic interact

When plants and plastic interact

Our knowledge of nanoparticle movements in plants mostly originates from experiments on metal and metal oxide nanoparticle–plant interactions. Determining the fate of plastic nanoparticles in plants is much more challenging because plant tissue is essentially a complex mix of biopolymers and the detection of plastic in this environment is challenging. Now, Sun et al. use labelled particles with different surface charges to show that processes similar to those of relatively inert metal or metal oxide nanoparticles occur in the roots for polystyrene plastic nanoparticles.
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