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Soluble Carbohydrates (soluble + carbohydrate)
Selected AbstractsSoluble carbohydrates in the nutrition of house longhorn beetle larvae, Hylotrupes bajulus (L.) (Col., Cerambycidae): from living sapwood to faecesJOURNAL OF APPLIED ENTOMOLOGY, Issue 9 2002W. Höll Living sapwood contains high amounts of sucrose, glucose, fructose and starch. These carbohydrates seem to be hydrolysed and metabolized during the production of the sapwood blocks. The faeces contain carbohydrates which are not present either in living sapwood or in the sapwood blocks: xylose and an oligosaccharide of uncertain composition. This oligosaccharide is the dominant water-soluble carbohydrate in the faeces. In contrast to living sapwood and sapwood blocks, the faeces contain considerable amounts of soluble ,-glucans. The results show that the composition and the amounts of carbohydrates differ significantly from that in the sapwood blocks (fodder for the larvae). The ,-glucans (starch) present in the wood are not significantly utilized by the larvae. Regarding soluble carbohydrates, diet wood has only little in common with the living wood of the standing tree. [source] Large-scale geographical trends in fruit traits of vertebrate-dispersed temperate plantsJOURNAL OF BIOGEOGRAPHY, Issue 4 2003Arndt Hampe Abstract Aim, To assess large-scale geographical trends in the character of fleshy, vertebrate-dispersed fruits. Location, Europe between central Sweden and southern Spain. Methods, Analyses of fruit of sixty-three plant species from twenty-nine families were compiled from four regional data sets. Four structural and five chemical fruit traits were analysed intraspecifically to control rigorously for phylogenetic lineage effects. Trends were examined in relation to various biological features of the considered species. Results, Contents of soluble carbohydrate and lipids decreased markedly northwards. Fruit diameter and fresh mass peaked at the wettest site, while the pulp water content remained more constant throughout the gradient than any other fruit trait. Ash content, seed number and seed mass did not change, while the nitrogen content showed conflicting trends. No relation was detected between observed variation in fruit traits and fruit type, fruit colour, ripening season, plant growth form, leaf longevity, or geographical distribution of the considered plant species. Main conclusions, Considerable intraspecific variability exists in vertebrate-dispersed fruits on large geographical scales. Climate presumably affects particularly those traits related to carbon and water gain and storage. Most research on fruit,frugivore interactions has been carried out on small spatial scales and failed to find matchings between frugivore communities and the character of fleshy fruits. I suggest that explicitly addressed large-scale surveys on the geographical variability of fruits and their disperser assemblages are needed to elucidate their spatial patterns and to determine the extent to which fleshy fruit traits are shaped by animals and/or abiotic factors. [source] Genetic analysis and QTL mapping of stalk digestibility and kernel composition in a high-oil maize mutant (Zea mays L.)PLANT BREEDING, Issue 3 2010H.-W. Wang With 1 figure and 5 tables Abstract A high-oil maize inbred line Ce03005 derived from ethylmethane-sulphonate mutagenesis was used to study the genetic basis of stalk digestibility and kernel chemical compositions, and evaluate the genetic relationship between traits. Quantitative trait loci (QTL) mapping employed 211 lines of F3 and F4 generations derived from Ce03005 × B73. Nuclear magnetic resonance and near-infrared reflectance spectrometry were used to analyse the following phenotypic traits: stalk digestibility and related traits including in vitro dry matter digestibility (IVDMD), in vitro cell wall digestibility (IVNDFD), neutral detergent fibre (NDF), acid detergent fibre (ADF), water soluble carbohydrate (WSC), and kernel composition including kernel oil content (KOC), kernel protein content (KPC) and kernel starch content (KSC). Correlation analysis indicated that IVDMD, IVNDFD and WSC were significantly (P = 0.01) positively correlated with KOC, while ADF and NDF were negatively correlated with KOC. Six QTL for IVDMD, five for IVNDFD, six for NDF, eight for ADF, three for WSC, eight for KOC, seven for KPC and 10 for KSC were detected in F3 and F4 generations. Five major QTL (R2 > 10) of qIVDMD6, qIVNDFD6, qNDF6, qADF6, qWSC6 andOlicm6 shared the same confidence interval on chromosome 6. The results suggested that KOC may be closely related or share the same QTL for stalk quality traits, and its change may have influences to the stalk components. [source] Does the 13C of foliage-respired CO2 and biochemical pools reflect the 13C of recently assimilated carbon?PLANT CELL & ENVIRONMENT, Issue 10 2009BEHZAD MORTAZAVI ABSTRACT Isotopic labelling experiments were conducted to assess relationships among 13C of recently assimilated carbon (,CA), foliage respiration (,CF), soluble carbohydrate (,CSC), leaf waxes (,CLW) and bulk organic matter (,COM). Slash pine, sweetgum and maize were grown under 13C depleted CO2 to label biomass and then placed under ambient conditions to monitor the loss of label. In pine and sweetgum, ,CF of labelled plants (,,44 and ,35,, respectively) rapidly approached control values but remained depleted by ,4,6, after 3,4 months. For these tree species, no or minimal label was lost from ,CSC, ,CLW and ,COM during the observation periods. ,CF and ,CSC of labelled maize plants rapidly changed and were indistinguishable from controls after 1 month, while ,CLW and ,COM more slowly approached control values and remained depleted by 2,6,. Changes in ,CF in slash pine and sweetgum fit a two-pool exponential model, with the fast turnover metabolic pool (,3,4 d half-life) constituting only 1,2% of the total. In maize, change in ,CF fits a single pool model with a half-life of 6.4 d. The 13C of foliage respiration and biochemical pools reflect temporally integrated values of ,CA, with change in isotopic composition dampened by the size of metabolic carbon reserves and turnover rates. [source] Resistance of apple trees to Cydia pomonella egg-laying due to leaf surface metabolitesENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 1 2008Nadia Lombarkia Abstract During host plant selection and particularly after alighting on a plant, chemical cues from the plant surface influence an insect's acceptance of the plant and, subsequently, its egg-laying behaviour. Primary metabolites in the phylloplane may be more important than hitherto known. We have shown that soluble carbohydrates, such as glucose, fructose, and sucrose, and sugar alcohols, such as sorbitol, quebrachitol, and myo -inositol, can be detected by insects after contacting the plant and that they positively influence egg-laying of the codling moth, Cydia pomonella (L.) (Lepidoptera: Tortricidae), on apple trees. We addressed the question whether a lack of these substances could also explain apple tree resistance to C. pomonella in terms of reduced egg-laying. Leaf surface washings were collected in an apple orchard by spraying water on the resistant cultivar X65-11 and on the susceptible cultivar P5R50A4. The washings were tested on a nylon cloth on isolated females under no-choice conditions. The washings were analysed and synthetic blends, each consisting of the six metabolites in the proportions established in the leaf surface washings of both cultivars, were then tested for their effect on egg-laying of C. pomonella. Dose,response egg-laying tests were carried out on substrates impregnated with the X65-11 leaf surface blend at 1, 100, 1 000, and 10 000 times the natural dose. Egg-laying behaviour in the bioassays with leaf surface washings of both cultivars closely resembled egg-laying in the orchard. Washings of P5R50A4 stimulated egg-laying to a greater extent than those of X65-11 and the water control. Synthetic blends reduced substrate acceptance and egg-laying, compared to the washings of X65-11. Ratios between components within the blend are responsible for this resistance. In conclusion, quantities and ratios of the six primary metabolites found on the leaf surface may influence host preference of C. pomonella as well as their egg-laying behaviour, thus they may play a role in the trees' resistance to the codling moth. [source] The growth respiration component in eddy CO2 flux from a Quercus ilex mediterranean forestGLOBAL CHANGE BIOLOGY, Issue 9 2004S. Rambal Abstract Ecosystem respiration, arising from soil decomposition as well as from plant maintenance and growth, has been shown to be the most important component of carbon exchange in most terrestrial ecosystems. The goal of this study was to estimate the growth component of whole-ecosystem respiration in a Mediterranean evergreen oak (Quercus ilex) forest over the course of 3 years. Ecosystem respiration (Reco) was determined from night-time carbon dioxide flux (Fc) using eddy correlation when friction velocity (u*) was greater than 0.35 m s,1 We postulated that growth respiration could be evaluated as a residual after removing modeled base Reco from whole-ecosystem Reco during periods when growth was most likely occurring. We observed that the model deviated from the night-time Fc -based Reco during the period from early February to early July with the largest discrepancies occurring at the end of May, coinciding with budburst when active aboveground growth and radial growth increment are greatest. The highest growth respiration rates were observed in 2001 with daily fluxes reaching up to 4 g C m,2. The cumulative growth respiration for the entire growth period gave total carbon losses of 170, 208, and 142 g C m,2 for 1999, 2001, and 2002, respectively. Biochemical analysis of soluble carbohydrates, starch, cellulose, hemicellulose, proteins, lignin, and lipids for leaves and stems allowed calculation of the total construction costs of the different growth components, which yielded values of 154, 200, and 150 g C for 3 years, respectively, corresponding well to estimated growth respiration. Estimates of both leaf and stem growth showed very large interannual variation, although average growth respiration coefficients and average yield of growth processes were fairly constant over the 3 years and close to literature values. The time course of the growth respiration may be explained by the growth pattern of leaves and stems and by cambial activity. This approach has potential applications for interpreting the effects of climate variation, disturbances, and management practices on growth and ecosystem respiration. [source] Soluble carbohydrates in the nutrition of house longhorn beetle larvae, Hylotrupes bajulus (L.) (Col., Cerambycidae): from living sapwood to faecesJOURNAL OF APPLIED ENTOMOLOGY, Issue 9 2002W. Höll Living sapwood contains high amounts of sucrose, glucose, fructose and starch. These carbohydrates seem to be hydrolysed and metabolized during the production of the sapwood blocks. The faeces contain carbohydrates which are not present either in living sapwood or in the sapwood blocks: xylose and an oligosaccharide of uncertain composition. This oligosaccharide is the dominant water-soluble carbohydrate in the faeces. In contrast to living sapwood and sapwood blocks, the faeces contain considerable amounts of soluble ,-glucans. The results show that the composition and the amounts of carbohydrates differ significantly from that in the sapwood blocks (fodder for the larvae). The ,-glucans (starch) present in the wood are not significantly utilized by the larvae. Regarding soluble carbohydrates, diet wood has only little in common with the living wood of the standing tree. [source] Physiological and biochemical traits involved in the genotypic variability to salt tolerance of Tunisian Cakile maritimaAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Megdiche Wided Abstract Cakile maritima (family: Brassicaceae) was collected from three provenances belonging to different bioclimatic stages (humid, semi arid and arid) in Tunisia to study their eco-physiological and biochemical responses to salinity. Seedlings were cultivated on inert sand for 20 days under NaCl treatments (0, 100, 200, 400 mm NaCl). Plant response to salinity was provenance- and salt-dependent. At 100 mm NaCl, growth parameters (leaf biomass, area, number per plant and relative growth rate) were improved in plants from Jerba (originating from arid bioclimatic stage) compared with the control, while growth was reduced in those from Tabarka (from humid area). High salt levels (400 mm NaCl) decreased the plant growth in the three provenances, but plants in Tabarka were the most salt sensitive. The relative salt tolerance of plants from Jerba and Bekalta provenances was associated with low levels of malondialdehyde as well as of electrolyte leakage and endoproteolytic activity. Salt reduced leaf hydration, the decrease in water content being dose-dependent and more pronounced in Tabarka. Increase in salinity led to significant increase in leaf succulence and decrease in leaf water potential, especially in Jerba plants. The plants from the latter displayed the highest leaf levels of Na+ and Cl,, proline, soluble carbohydrates, soluble proteins, and polyphenols. Overall, the higher salt tolerance of plants from Jerba provenance, and to a lower extent of those from Bekalta, may be partly related to their better capacity for osmotic adjustment and to limit oxidative damage when salt-challenged. Résumé Cakile maritima a été collecté (famille des Brassicaceae) dans trois provenances appartenant à des étages bioclimatiques différentes (humide, semi-aride et aride) de la Tunisie, dans le but d'étudier leurs réponses éco-physiologique et biochimique à la salinité. Des plantules ont été cultivées dans du sable inerte pendant vingt jours avec des doses croissantes de NaCl (0, 100, 200 et 400 mm NaCl). La réponse de Cakile maritima dépend de la provenance et de la salinité du milieu. A 100 mm de NaCl, les paramètres de croissance (biomasse, surface et nombre des feuilles par plante ainsi que le taux de la croissance relative) ont été améliorés chez Djerba (zone bioclimatique aride) par comparaison aux plantes témoins, tandis que la croissance a été réduite chez Tabarka (zone humide). A la plus forte dose de sel (400 mm), une réduction de la croissance des trois provenances a été enregistrée avec une nette sensibilité chez les plantes de la provenance Tabarka. La tolérance relative des deux provenances Djerba et Bekalta est associée à une faible teneur en malondialdéhyde ainsi qu'une fuite d'électrolyte et activité endo-protéolytique modérées. Le traitement salin a réduit l'hydratation des feuilles et cette diminution du contenu en eau est dose-dépendante et elle est plus prononcée chez Tabarka. En outre, l'augmentation de la salinité du milieu a entrainé une élévation de la succulence des feuilles concomitante à une diminution du potentiel hydrique notamment chez Djerba. Les plantes de cette dernière ont été les plus riches en Na+ et Cl - , en proline, carbohydrates, en protéines solubles et en polyphénols. En général, la tolérance au sel de la provenance Djerba, et à moindre degré Bekalta, est en partie reliée à la meilleure capacité d'ajustement osmotique et la limitation des dommages oxydatifs sous stress salin. [source] Infection of Arabidopsis thaliana leaves with Albugo candida (white blister rust) causes a reprogramming of host metabolismMOLECULAR PLANT PATHOLOGY, Issue 2 2000Hsueh-Mei Chou Albugo candida (Pers.) (O.) Kunze is a biotrophic pathogen which infects the crucifer Arabidopsis thaliana (L.) Heynh forming discrete areas of infection. Eight days after inoculation of leaves, white blisters became visible on the under surface of the leaf although no symptoms were apparent on the upper surface. By day 14, the region of leaf invaded by fungal mycelium had become chlorotic. Recently it has been hypothesized that an accumulation of soluble carbohydrates, following an increase in invertase activity, may trigger sugar signal transduction pathways leading to the repression of photosynthetic gene expression and to the induction of defence proteins. This hypothesis was investigated by quantifying localized changes in carbohydrate and photosynthetic metabolism and the expression of genes encoding photosynthetic and defence proteins. Quantitative imaging of chlorophyll fluorescence revealed that the rate of photosynthesis declined progressively in the invaded regions of the leaf. However, in uninfected regions of the infected leaf the rate of photosynthesis was similar to that measured in the control leaf until late on during the infection cycle when it declined. Images of nonphotochemical fluorescence quenching (NPQ) suggested that the capacity of the Calvin cycle had been reduced in infected regions and that there was a complex metabolic heterogeneity within the infected leaf. A. candida also caused localized changes in the carbohydrate metabolism of the leaf; soluble carbohydrates accumulated in the infected region whereas the amount of starch declined. The reverse was seen in uninfected regions of the infected leaf; carbohydrates did not accumulate until late on during infection and the amount of starch increased as the infection progressed. There was an increase in the activity of invertases which was confined to regions of the leaf invaded by the fungal mycelium. The increase in apoplastic invertase activity was of host origin, as mRNA levels of the AT,FRUCT1 gene (measured by semiquantitative RT-PCR) increased 40-fold in the infected region. The increase in soluble invertase activity resulted from the appearance of a new isoform in the invaded region of the leaf. Current evidence suggests that this was of fungal origin. Northern blot analysis of cab and rbcS showed that photosynthetic gene expression was repressed in the infected leaf from 6 days after inoculation (DAI) when compared to control leaves. In contrast, there was no detectable induction of defence proteins in the infected leaf. These data are discussed in the context of the sugar-sensing hypothesis presented above. [source] Simultaneous measurement of water flow velocity and solute transport in xylem and phloem of adult plants of Ricinus communis over a daily time course by nuclear magnetic resonance spectrometryPLANT CELL & ENVIRONMENT, Issue 5 2001A. D. Peuke ABSTRACT A new method for simultaneously quantifying rates of flow in xylem and phloem using the FLASH imaging capabilities of nuclear magnetic resonance (NMR) spectrometry was applied in this study. The method has a time resolution of up to 4 min (for the xylem) and was used to measure the velocity of flows in phloem and xylem for periods of several hours to days. For the first time, diurnal time course measurements of flow velocities and apparent volume flows in phloem and xylem in the hypocotyl of 40-d-old Ricinus communis L were obtained. Additional data on gas exchange and the chemical composition of leaves, xylem and phloem sap were used to assess the role of leaves as sinks for xylem sap and sources for phloem. The velocity in the phloem (0·250 ± 0·004 mm s,1) was constant over a full day and not notably affected by the light/dark cycle. Sucrose was loaded into the phloem and transported at night, owing to degradation of starch accumulated during the day. Concentrations of solutes in the phloem were generally less during the night than during the day but varied little within either the day or night. In contrast to the phloem, flow velocities in the xylem were about 1·6-fold higher in the light (0·401 ± 0·004 mm s,1) than in the dark (0·255 ± 0·003 mm s,1) and volume flow varied commensurately. Larger delays were observed in changes to xylem flow velocity with variation in light than in gas exchange. The relative rates of solute transport during day and night were estimated on the basis of relative flow and solute concentrations in xylem and phloem. In general, changes in relative flow rates were compensated for by changes in solute concentration during the daily light/dark cycle. However, the major solutes (K+, NO3,) varied appreciably in relative concentrations. Hence the regulation of loading into transport systems seems to be more important to the overall process of solute transport than do changes in mass flow. Due to transport behaviour, the chemical composition of leaves varied during the day only with regard to starch and soluble carbohydrates. [source] | |||||||||||||||||||