References of "Journal of Experimental Botany"
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See detailWater stress drastically reduces root growth and inulin yield in Cichorium intybus (var. sativum) independently of photosynthesis
Vandoorne, Bertrand; Mathieu, Anne-Sophie; Van den Ende, Wim et al

in Journal of Experimental Botany (2012), 63(12), 4359-4373

Root chicory (Cichorium intybus var. sativum) is a cash crop cultivated for inulin production in Western Europe. This plant could be exposed to severe water stress during the three last months of their ... [more ▼]

Root chicory (Cichorium intybus var. sativum) is a cash crop cultivated for inulin production in Western Europe. This plant could be exposed to severe water stress during the three last months of their six months growing period. The aim of this study was to quantify the effect of a progressive decline in water availability on plant growth, photosynthesis and sugar metabolism and to determine its impact on inulin production. Water stress drastically decreased root fresh and dry weight, leaf number, total leaf area and stomatal conductance. Stressed plants, however, increased their water use efficiency, decreased the shoot to root ratio and lowered their osmotic potential through soluble sugar accumulation. Despite a decrease in photosynthetic pigments, the light phase of the photosynthesis remained unaffected under water stress. Water stress increased sucrose phosphate synthase (SPS) activity in the leaves, but not in the roots. Water stress inhibited sucrose:sucrose 1-fructosyltransferase (1-SST) and fructan:fructan 1 fructosyltransferase (1—FFT) after 19 weeks of culture and slightly increased fructan 1-exohydrolase activities (1-FEH). The root inulin concentration and the mean degree of polymerisation (DP) of the inulin chain remained however unaffected by water stress. It is concluded that root chicory displayed resistance to water stress, but that such a resistance is obtained at the expense of growth which, in turn, leads to significant decrease in inulin production. [less ▲]

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See detailATSPO-related protein localizes to the early secretory pathway in Arabidopsis, but is targeted to mitochondria when expressed in yeast
Vanhee, Celine; Guillon, Stéphanie; Masquelier, Danièle et al

in Journal of Experimental Botany (2011), 62(2), 497-508

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See detailMetal accumulation in tobacco expressing Arabidopsis halleri metal hyperaccumulation gene depends on external supply.
Barabasz, Anna; Krämer, Ute; Hanikenne, Marc ULg et al

in Journal of Experimental Botany (2010), 61(11), 3057-67

Engineering enhanced transport of zinc to the aerial parts of plants is a major goal in bio-fortification. In Arabidopsis halleri, high constitutive expression of the AhHMA4 gene encoding a metal pump of ... [more ▼]

Engineering enhanced transport of zinc to the aerial parts of plants is a major goal in bio-fortification. In Arabidopsis halleri, high constitutive expression of the AhHMA4 gene encoding a metal pump of the P(1B)-ATPase family is necessary for both Zn hyperaccumulation and the full extent of Zn and Cd hypertolerance that are characteristic of this species. In this study, an AhHMA4 cDNA was introduced into N. tabacum var. Xanthi for expression under the control of its endogenous A. halleri promoter known to confer high and cell-type specific expression levels in both A. halleri and the non-hyperaccumulator A. thaliana. The transgene was expressed at similar levels in both roots and shoots upon long-term exposure to low Zn, control, and increased Zn concentrations. A down-regulation of AhHMA4 transcript levels was detected with 10 muM Zn resupply to tobacco plants cultivated in low Zn concentrations. In general, a transcriptional regulation of AhHMA4 in tobacco contrasted with the constitutively high expression previously observed in A. halleri. Differences in root/shoot partitioning of Zn and Cd between transgenic lines and the wild type were strongly dependent on metal concentrations in the hydroponic medium. Under low Zn conditions, an increased Zn accumulation in the upper leaves in the AhHMA4-expressing lines was detected. Moreover, transgenic plants exposed to cadmium accumulated less metal than the wild type. Both modifications of zinc and cadmium accumulation are noteworthy outcomes from the biofortification perspective and healthy food production. Expression of AhHMA4 may be useful in crops grown on soils poor in Zn. [less ▲]

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See detailModel-assisted integration of physiological and environmental constraints affecting the dynamic and spatial patterns of root water uptake from soils
Draye, X.; Kim, Y.; Lobet, Guillaume ULg et al

in Journal of Experimental Botany (2010), 61(8), 2145--2155

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See detailAttacks by a piercing-sucking insect (Myzus persicae Sultzer) or a chewing insect (Leptinotarsa decemlineata Say) on potato plants (Solanum tuberosum L.) induce differential changes in volatile compound release and oxylipin synthesis
Gosset, Virginie; Harmel, Nicolas; Goebel, Cornelia et al

in Journal of Experimental Botany (2009), 60(4), 1231-1240

Plant defensive strategies bring into play blends of compounds dependent on the type of attacker and coming from different synthesis pathways. Interest in the field is mainly focused on volatile organic ... [more ▼]

Plant defensive strategies bring into play blends of compounds dependent on the type of attacker and coming from different synthesis pathways. Interest in the field is mainly focused on volatile organic compounds (VOCs) and jasmonic acid (JA). By contrast, little is known about the oxidized polyunsaturated fatty acids (PUFAs), such as PUFA-hydroperoxides, PUFA-hydroxides, or PUFA-ketones. PUFA-hydroperoxides and their derivatives might be involved in stress response and show antimicrobial activities. Hydroperoxides are also precursors of JA and some volatile compounds. In this paper, the differential biochemical response of a plant against insects with distinct feeding behaviours is characterized not only in terms of VOC signature and JA profile but also in terms of their precursors synthesized through the lipoxygenase (LOX)-pathway at the early stage of the plant response. For this purpose, two leading pests of potato with distinct feeding behaviours were used: the Colorado Potato Beetle (Leptinotarsa decemlineata Say), a chewing herbivore, and the Green Peach Aphid (Myzus persicae Sulzer), a piercing-sucking insect. The volatile signatures identified clearly differ in function with the feeding behaviour of the attacker and the aphid, which causes the smaller damages, triggers the emission of a higher number of volatiles. In addition, 9-LOX products, which are usually associated with defence against pathogens, were exclusively activated by aphid attack. Furthermore, a correlation between volatiles and JA accumulation and the evolution of their precursors was determined. Finally, the role of the insect itself on the plant response after insect infestation was highlighted. [less ▲]

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See detailPotato (Solanum Tuberosum L.) Tuber Ageing Induces Changes In The Proteome And Antioxidants Associated With The Sprouting Pattern
Delaplace, Pierre ULg; Fauconnier, Marie-Laure ULg; Sergeant, K. et al

in Journal of Experimental Botany (2009), 60(4), 1273-1288

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See detailChronic ozone exposure affects leaf senescence of adult beech trees: a chlorophyll fluorescence approach
Gielen, B.; Low, M.; Deckmyn, G. et al

in Journal of Experimental Botany (2007), 58(4), 785-795

Accelerated leaf senescence is one of the harmful effects of elevated tropospheric ozone concentrations ([O-3]) on plants. The number of studies dealing with mature forest trees is scarce however ... [more ▼]

Accelerated leaf senescence is one of the harmful effects of elevated tropospheric ozone concentrations ([O-3]) on plants. The number of studies dealing with mature forest trees is scarce however. Therefore, five 66-year-old beech trees (Fagus sylvatica L.) have been exposed to twice-ambient (2xambient) [O-3] levels by means of a free-air canopy O-3 exposure system. During the sixth year of exposure, the hypothesis of accelerated leaf senescence in 2xambient [O-3] compared with ambient [O-3] trees was tested for both sun and shade leaves. Chlorophyll (chl) fluorescence was used to assess the photosynthetic quantum yield, and chl fluorescence images were processed to compare functional leaf homogeneity and the proportion of O-3-injured leaf area (stipples) under ambient and 2xambient [O-3] regimes. Based on the analysis of chl fluorescence images, sun leaves of both ambient and 2xambient [O-3] trees had apparently developed typical necrotic O-3 stipples during high O-3 episodes in summer, while accelerated senescence was only observed with sun leaves of 2xambient [O-3] trees. This latter effect was indicated along with a faster decrease of photosynthetic quantum yield, but without evidence of changes in non-photochemical quenching. Overall, treatment effects were small and varied among trees. Therefore, compared with ambient [O-3], the consequence of the observed O-3-induced accelerated leaf senescence for the carbon budget is likely limited. [less ▲]

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See detailNematode Infection And Reproduction In Transgenic And Mutant Arabidopsis And Tobacco With An Altered Phenylpropanoid Metabolism
Wuyts, Nathalie; Lognay, Georges ULg; Swennen, R. et al

in Journal of Experimental Botany (2006), 57(11), 2825-2835

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See detailCytokinin levels in leaves, leaf exudate and shoot apical meristem of Arabidopsis thaliana during floral transition
Corbesier, Laurent; Prinsen, Els; Jacqmard, Annie ULg et al

in Journal of Experimental Botany (2003), 54(392), 2511-2517

Understanding the complete picture of floral transition is still impaired by the fact that physiological studies mainly concern plant species whose genetics is poorly known, and vice versa. Arabidopsis ... [more ▼]

Understanding the complete picture of floral transition is still impaired by the fact that physiological studies mainly concern plant species whose genetics is poorly known, and vice versa. Arabidopsis thaliana has been successfully used to unravel signalling pathways by genetic and molecular approaches, but analyses are still required to determine the physiological signals involved in the control of floral transition. In this work, the putative role of cytokinins was investigated using vegetative plants of Arabidopsis (Columbia) induced to flower synchronously by a single 22 h long day. Cytokinins were analysed in leaf extracts, leaf phloem exudate and in the shoot apical meristem at different times during floral transition. It was found that, in both the leaf tissues and leaf exudate, isopentenyladenine forms of cytokinins increased from 16 h after the start of the long day. At 30 h, the shoot apical meristem of induced plants contained more isopentenyladenine and zeatin than vegetative controls. These cytokinin increases correlate well with the early events of floral transition. [less ▲]

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See detailDarkness promotes flowering in the absolute long-day requiring plant, Lolium temulentum L. Ceres
Périlleux, Claire ULg; Bernier, Georges ULg; Kinet, Jean-Marie

in Journal of Experimental Botany (1997), 48(307), 349--351

Vegetative plants of the long-day grass Lolium temulentum L. Ceres were exposed to threshold long days or light breaks. Protracted darkness given just afterwards clearly promoted flowering and was weakly ... [more ▼]

Vegetative plants of the long-day grass Lolium temulentum L. Ceres were exposed to threshold long days or light breaks. Protracted darkness given just afterwards clearly promoted flowering and was weakly inductive on its own. The promotive effect of darkness was restricted to floral induction since further apical development was weak. [less ▲]

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See detailBiological clock and photoperiodism in Lolium temulentum Ceres
Périlleux, Claire ULg; Hustin, Cécile; Bernier, Georges ULg

in Journal of Experimental Botany (1997), 48

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See detailPHOTOREDUCTION OF PROTOCHLOROPHYLLIDE TO CHLOROPHYLLIDE IN 2-D-OLD DARK-GROWN BEAN (PHASEOLUS-VULGARIS CV COMMODORE) LEAVES - COMPARISON WITH 10-D-OLD DARK-GROWN (ETIOLATED) LEAVES
SCHOEFS, B.; Franck, Fabrice ULg

in Journal of Experimental Botany (1993), 44(263), 1053-1057

Two-d-old leaves which do not contain prolamellar bodies synthesize active protochlorophyllide in darkness. When protochlorophyllide is photoreduced by one intense white flash, a main chlorophyllide ... [more ▼]

Two-d-old leaves which do not contain prolamellar bodies synthesize active protochlorophyllide in darkness. When protochlorophyllide is photoreduced by one intense white flash, a main chlorophyllide species emitting at 690 nm is formed. After the photoreduction, the emission maximum is shifted to 675 nm within 5 s. This result suggests that in young leaves, chlorophyllide formed after one flash is quickly released from the active site of NADPH: protochlorophyllide oxidoreductase. This interpretation is strenghtened by time-resolved fluorescence measurements at room temperature, showing that 675 nm emitting chlorophyllide does not transfer excitation energy to the 696 nm emitting chlorophyllide which is formed in very low amount. In 10-d-old bean leaves, the 690 nm chlorophyllide emitting species formed after one short flash undergoes the well-known rapid and Shibata spectral shifts. The 675 nm emitting chlorophyllide appears only as a shoulder. At both ages, the fluorescence intensity of the active protochlorophyllide strongly decreases during and after photoreduction, suggesting rapid modifications in the close environment of the pigment. [less ▲]

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See detailReproductive Development in Lolium temulentum L.: Spike Morphogenesis and Grain Set Limitations
Périlleux, Claire ULg; Bernier, Georges ULg; Kinet, Jean Marie

in Journal of Experimental Botany (1991), 42(4), 501

Reproductive development in cereals is not easy to investigate because their quantitative response to environmental factors makes it difficult to synchronize the plants. In this paper, one of our aims was ... [more ▼]

Reproductive development in cereals is not easy to investigate because their quantitative response to environmental factors makes it difficult to synchronize the plants. In this paper, one of our aims was to assess whether Lolium temulentum strain Ceres, a qualitative long-day grass, could serve as a model of reproductive development for cereals. The morphological patterns from floral transition to seed set were studied. [less ▲]

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