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- Junker, Robert R., et al.
(författare)
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Covariation and phenotypic integration in chemical communication displays : Biosynthetic constraints and eco-evolutionary implications
- 2018
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Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 220:3, s. 739-749
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Tidskriftsartikel (refereegranskat)abstract
- Chemical communication is ubiquitous. The identification of conserved structural elements in visual and acoustic communication is well established, but comparable information on chemical communication displays (CCDs) is lacking. We assessed the phenotypic integration of CCDs in a meta-analysis to characterize patterns of covariation in CCDs and identified functional or biosynthetically constrained modules. Poorly integrated plant CCDs (i.e. low covariation between scent compounds) support the notion that plants often utilize one or few key compounds to repel antagonists or to attract pollinators and enemies of herbivores. Animal CCDs (mostly insect pheromones) were usually more integrated than those of plants (i.e. stronger covariation), suggesting that animals communicate via fixed proportions among compounds. Both plant and animal CCDs were composed of modules, which are groups of strongly covarying compounds. Biosynthetic similarity of compounds revealed biosynthetic constraints in the covariation patterns of plant CCDs. We provide a novel perspective on chemical communication and a basis for future investigations on structural properties of CCDs. This will facilitate identifying modules and biosynthetic constraints that may affect the outcome of selection and thus provide a predictive framework for evolutionary trajectories of CCDs in plants and animals.
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- Khaling, Eliezer, et al.
(författare)
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Ozone affects growth and development of Pieris brassicae on the wild host plant Brassica nigra
- 2015
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Ingår i: Environmental Pollution. - : Elsevier BV. - 0269-7491 .- 1873-6424. ; 199, s. 119-129
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Tidskriftsartikel (refereegranskat)abstract
- When plants are exposed to ozone they exhibit changes in both primary and secondary metabolism, which may affect their interactions with herbivorous insects. Here we investigated the performance and preferences of the specialist herbivore Pieris brassicae on the wild plant Brassica nigra under elevated ozone conditions. The direct and indirect effects of ozone on the plant-herbivore system were studied. In both cases ozone exposure had a negative effect on P. brassicae development. However, in dual-choice tests larvae preferentially consumed plant material previously fumigated with the highest concentration tested, showing a lack of correlation between larval preference and performance on ozone exposed plants. Metabolomic analysis of leaf material subjected to combinations of ozone and herbivore-feeding, and focussing on known defence metabolites, indicated that P. brassicae behaviour and performance were associated with ozone-induced alterations to glucosinolate and phenolic pools.
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- Papazian, Stefano, 1986-, et al.
(författare)
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Leaf metabolic signatures induced by real and simulated herbivory in black mustard (Brassica nigra)
- 2019
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Ingår i: Metabolomics. - : Springer. - 1573-3882 .- 1573-3890. ; 15:10
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Tidskriftsartikel (refereegranskat)abstract
- Introduction The oxylipin methyl jasmonate (MeJA) is a plant hormone active in response signalling and defence against herbivores. Although MeJA is applied experimentally to mimic herbivory and induce plant defences, its downstream effects on the plant metabolome are largely uncharacterized, especially in the context of primary growth and tissue-specificity of the response. Objectives We investigated the effects of MeJA-simulated and real caterpillar herbivory on the foliar metabolome of the wild plant Brassica nigra and monitored the herbivore-induced responses in relation to leaf ontogeny. Methods As single or multiple herbivory treatments, MeJA- and mock-sprayed plants were consecutively exposed to caterpillars or left untreated. Gas chromatography (GC) and liquid chromatography (LC) time-of-flight mass-spectrometry (TOF-MS) were combined to analyse foliar compounds, including central primary and specialized defensive plant metabolites. Results Plant responses were stronger in young leaves, which simultaneously induced higher chlorophyll levels. Both MeJA and caterpillar herbivory induced similar, but not identical, accumulation of tricarboxylic acids (TCAs), glucosinolates (GSLs) and phenylpropanoids (PPs), but only caterpillar feeding led to depletion of amino acids. MeJA followed by caterpillars caused higher induction of defence compounds, including a three-fold increase in the major defence compound allyl-GSL (sinigrin). When feeding on MeJA-treated plants, caterpillars gained less weight indicative of the reduced host-plant quality and enhanced resistance. Conclusions The metabolomics approach showed that plant responses induced by herbivory extend beyond the regulation of defence metabolism and are tightly modulated throughout leaf development. This leads to a new understanding of the plant metabolic potential that can be exploited for future plant protection strategies.
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- Van Puyvelde, L., et al.
(författare)
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Photoluminescence investigation of Cu2ZnSnS4 thin film solar cells
- 2015
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Ingår i: Thin Solid Films. - : Elsevier BV. - 0040-6090 .- 1879-2731. ; 582, s. 146-150
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Tidskriftsartikel (refereegranskat)abstract
- Cu2ZnSnS4 (CZTS) is a promising absorber for thin film solar cells which is non-toxic and consists of only abundant elements. In order to achieve higher solar cell efficiencies for this material, a better understanding about its defect structure is necessary. In this paper photoluminescence (PL) from sputtered CZTS thin film solar cells which differ in buffer layer thickness was studied. In the PL spectra three broad peaks could be distinguished between 0.9 and 1.3 eV. The PL measurements as a function of temperature and excitation power density revealed the presence of potential fluctuations. The separations between the band edge of the photoluminescence excitation signal and the PL emission peaks are large, which indicates that PL involves trapping of carriers by deep-level defects.
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