References of "Fauconnier, Marie-Laure"
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See detailEvaluation of different hydrocolloids to improve dough rheological properties and bread quality of potato-wheat flour
Liu, Xingli ULg; Mu, Taihua; Yamul, Karim Diego et al

in Journal of Industrial and Engineering Chemistry (in press)

The aim of study was to investigate the effect of hydroxylpropylmethylcellulose (HPMC), arabic gum (AG), konjac glucomannan (KG) and apple pectin (AP) at 2% (w/w, potato-wheat flour basis) on the potato ... [more ▼]

The aim of study was to investigate the effect of hydroxylpropylmethylcellulose (HPMC), arabic gum (AG), konjac glucomannan (KG) and apple pectin (AP) at 2% (w/w, potato-wheat flour basis) on the potato-wheat dough (the mass ratio was 1:1) rheological, fermentation properties and its bread quality. The tan δ of potato-wheat dough was significantly increased by adding HPMC compared to those of without adding hydrocolloids (from 0.337 to 0.425), which was close to wheat dough (0.531). Moreover, the dough height during fermentation process was significantly improved by adding hydrocolloids, with the order of HPMC (23.1mm) > AP (19.3mm) > AG (18.6mm) > KG (13.6mm). In addition, the potato-wheat protein bands of potato-wheat dough turned pale by adding hydrocolloids, suggesting higher molecular weight aggregation formed between proteins-hydrocolloids or proteins-proteins after fermentation process. Furthermore, HPMC significantly increased specific volume (from 1.45 to 2.22 ml/g), and hydrocolloids restrained the starch retrogradation of potato-wheat breads. [less ▲]

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See detailFirst Characterization of the Volatile Organic Compounds Emitted by Banana Plants (Musa sp.)
Berhal, Chadi ULg; De Clerck, Caroline ULg; LEVICEK, Carolina et al

Conference (2017, June 16)

Banana fruit (Musa sp.) ranks fourth in developing world's production, and has economical and nutritional key values. The popular and most dominant variety of the dessert banana group is the Cavendish ... [more ▼]

Banana fruit (Musa sp.) ranks fourth in developing world's production, and has economical and nutritional key values. The popular and most dominant variety of the dessert banana group is the Cavendish variety, and Plantain represents that status for the cooking banana group. Despite the importance of the Volatile Organic Compounds (VOCs), which are secondary metabolites with a high vapour pressure, in their utility in the plant protection and communication processes, they were never documented for the plant itself. Thus, the aim of this PHD thesis is to study the VOCs emitted by the plant, rather than their fruits or flowers. A protocol was optimized for the extraction of the banana plant's VOCs. The results of the first analysis showed 11 VOCs for the Cavendish, mainly (E,E)-α-farnesene (87.90 ± 11.28 ng/µl), methyl salicylate (33.82 ± 14.29) and 6-methyl-5-hepten-2-one (29.60 ± 11.66), and 14 VOCs for the Pacific Plantain cultivars, mainly (Z,E)-α-farnesene (799.64 ± 503.15),(E,E)-α-farnesene (571.24 ± 381.70) and (E) β ocimene (241.76 ± 158.49). Most of these compounds belong to the terpenes group (8 for Cavendish, 10 for Pacific Plantain). The other compounds detected were ketones, esters and aldehydes. Eight compounds were common between the two varieties (myrcene, Z and E β-ocimene, 6-methyl-5-hepten-2 one, 6-methyl-3,5-hepadien-2-one, a-farnesene, methyl salicylate and β-ionone). This exploratory study paves the way for an in-depth characterisation of VOCs emitted by Musa plants. [less ▲]

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See detailPhenotyping of Brassica napus L. plantlets affected during in vitro growth by the presence of epoxiconazole.
Durenne, Bastien ULg; Blondel, Alodie; Ducat, Nathalie et al

in 7th International Symposium on Brassicas Abstract Book (2017, May 24)

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See detailStudy of volatile organic compounds active against barley pathogens
De Clerck, Caroline ULg; Kaddes, Amine ULg; Fiers, Marie et al

Conference (2017, May 23)

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See detailStudy of VOCs in the interaction between Banana and Foc TR4
Berhal, Chadi ULg; De Clerck, Caroline ULg; LEVICEK, Carolina et al

Poster (2017, May 23)

Banana fruit (Musa sp.) ranks fourth in term of worldwide production, and has economical and nutritional key values. The popular and most dominant variety of the dessert banana group is the Cavendish ... [more ▼]

Banana fruit (Musa sp.) ranks fourth in term of worldwide production, and has economical and nutritional key values. The popular and most dominant variety of the dessert banana group is the Cavendish variety. Nowadays, the Cavendish is endangered by the newly emergent race of the Panama disease, caused by the fungal pathogen Fusarium oxysporum f.sp. cubense TR4 (Foc TR4). Despite the importance of the Volatile Organic Compounds (VOCs), which are secondary metabolites with a high vapour pressure, in their utility in the plant protection processes, they were never documented as a way to manage this disease on Cavendish. Thus, the aim of this PhD thesis is to study the VOCs in the specific interaction Cavendish/Foc TR4, as a way to manage this threat. Based on the work previously done with other plants at Gembloux Agro-Bio Tech/University of Liège/Belgium, a protocol was optimized for the extraction of the banana plant’s VOCs. And in parallel, models of in-vitro and in-vivo inoculations are under development, in order to distinguish the root zone from the upper part of the plant in the study. The results of the first analysis showed that the majority of the Cavendish VOCs belongs to the terpenes group, as well as ketones and an organic ester. The identified key VOCs of the interaction will be subject to toxicity tests, in order to determine their effect on the development of the plant and the pathogen. The banana plant is a staple food for more than 400 Million people in the world, while this disease persists as a major threat for its production, and this original study could contribute to the fight against this threatening disease. [less ▲]

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See detailFirst Characterisation of Volatile Organic Compounds Emitted by Banana Plants
Berhal, Chadi ULg; De Clerck, Caroline ULg; Fauconnier, Marie-Laure ULg et al

in Scientific Reports (2017)

Banana (Musa sp.) ranks fourth in term of worldwide fruit production, and has economical and nutritional key values. The Cavendish cultivars correspond to more than 90% of the production of dessert banana ... [more ▼]

Banana (Musa sp.) ranks fourth in term of worldwide fruit production, and has economical and nutritional key values. The Cavendish cultivars correspond to more than 90% of the production of dessert banana while cooking cultivars are widely consumed locally around the banana belt production area. Many plants, if not all, produce Volatile Organic Compounds (VOCs) as a means of communication with their environment. Although flower and fruit VOCs have been studied for banana, the VOCs produced by the plant have never been identified despite their importance in plant health and development. A volatile collection methodology was optimized to improve the sensitivity and reproducibility of VOCs analysis from banana plants. We have identified 11 VOCs for the Cavendish, mainly (E,E)-α-farnesene (87.90 ± 11.28 ng/μl), methyl salicylate (33.82 ± 14.29) and 6-methyl-5-hepten-2-one (29.60 ± 11.66), and 14 VOCs for the Pacific Plantain cultivar, mainly (Z,E)-α-farnesene (799.64 ± 503.15), (E,E)-α-farnesene (571.24 ± 381.70) and (E) β ocimene (241.76 ± 158.49). This exploratory study paves the way for an in-depth characterisation of VOCs emitted by Musa plants. [less ▲]

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See detailGrazing-induced BVOC fluxes from a managed grassland
Mozaffar, Ahsan ULg; Schoon, N.; Bachy, Aurélie ULg et al

Poster (2017, April 28)

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See detailProfil d'acides gras et stabilité oxydative d'huiles de brisures d'amandons et d'écarts de tri des amandes
Houmy, Nadia ULg; Melhaoui, R; Sindic, Marianne ULg et al

Conference (2017, April 27)

Dans la région orientale du Maroc, en outre du projet *PROFAO, la filière Amandier bénéficie d'une attention particulière. Cependant, les opérations de concassage et de triage des amandes se font encore ... [more ▼]

Dans la région orientale du Maroc, en outre du projet *PROFAO, la filière Amandier bénéficie d'une attention particulière. Cependant, les opérations de concassage et de triage des amandes se font encore de façon artisanale. Dans un but de valorisation après le décorticage/concassage, les brisures et les écarts de tri des amandes, ayant une faible valeur marchande, servent à l'extraction d'huile pour usage alimentaire et cosmétique. Ce travail porte sur l'analyse chimique d'huiles de brisures d'amandes (HbA) et la détermination de leur stabilité oxydative. Ainsi sur trois compagnes agricoles consécutives 2014, 2015, 2016, des analyses par CPG FID des profils d'acides gras (AG) des HbA des variétés Marcona Ferragnes-Ferraduel, ont été effectuées. L'acide Oléique (C18:1) et l'acide Linoléique (C18:2) sont les deux AG majoritaires qui caractérisent les profils d'AG des HbA. Selon l'année de récolte, ces HbA ont montré des variations inter variétale, les différences observées sont significatives et sont de l'ordre de 15 % pour C18:1 et de 13 % pour C18:2. Ainsi la teneur des HbA analysées en C18:1 varie entre un taux-max de 72 % enregistré en 2013/2014 pour Ferrangnes-Ferraduel et un taux-minima de 57 % observé en 2015/2016 pour Marcona. La même remarque pour le C18:2 avec une teneur minimum de 17 % enregistré en 2013/2014 pour Ferragnes-Ferraduel et une teneur maximum de 30 % observé en 2015/2016 pour Marcona. Pour le rapport O/L la plus grande différence a été observée en 2013/2014, avec un ratio O/L de 4,1 pour l'HbA Ferragnes-Ferraduel et de 1,95 pour Marcona. Les résultats observés pour la stabilité oxydative des Hba estimée par des tests Rancimat montrent des valeurs qui varient entre un minimum de 20h pour l'HbA Marcona en 2013/2014 et un maximum de 29h pour l'HbA Ferragnes Ferraduel en 2015/2016. On note une corrélation positive entre la stabilité oxydative et la teneur des HbA en C18:1 ainsi qu'avec le ratio O/L. La suite logique de ce travail est la recherche d'une correlation entre la stabilité oxydative et les composants mineurs de l'huile notamment ceux à activité antioxydante tel les tocophérols. [less ▲]

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See detailProfil d'acides gras et acides aminés essentiels de la vainde ovine de la race Beni-Guil conduite en élevage semi-extensif dans l'est du Maroc
Belhaj, Kamal; Mansouri, Farid; Sindic, Marianne ULg et al

Poster (2017, April 27)

Les viandes sont commercialisées sous forme de muscles prêts à découper ou de portions « pièces »prêtes à cuire. La couleur de la viande est le premier paramètre de qualité perçue par le consommateur ... [more ▼]

Les viandes sont commercialisées sous forme de muscles prêts à découper ou de portions « pièces »prêtes à cuire. La couleur de la viande est le premier paramètre de qualité perçue par le consommateur, ensuite les paramètres de qualité organoleptiques, hygiénique et nutritionnelle deviennent déterminants et le guide dans son choix. La viande ovine de la race Béni-Guil, qui bénéficie de l’Indication géographique protégée est réputée pour sa qualité gustative et nutritionnelle mais uniquement sur la base de tests hédonique. De ce fait, vient cette étude sur l’analyse de la couleur et des profils lipidiques et protéiques du muscle long dorsal (LDM), un muscle de référence et morceau de viande apprécié par le consommateur. L’analyse de la couleur a montré que LDM de la race béni-guil a une couleur rouge vif très recherché par le consommateur avec un indice de rouge de 14,74. Les résultats d’analyse par GC-FID a permis l’identification de 27 d’acide gras (AG). Comme il a été signalé dans d’autres études (1,2). On observe, qu’un apport de suppléments alimentaires à base d’orge et de son en période critique (sécheresse, ou période de soudure), engendrerait des variations assez importantes par rapport à une conduite au pâturage. En effet, au niveau du profil lipidique le taux d’AG saturés augmente de 40% à 49% au dépend du taux d’AG insaturés qui chute de 60 à 51%. Pour les AG majoritaires, les plus importantes variations ont été enregistrées pour la teneur en acide oléique (C18:1n9) qui chute de 38% à 35%, en faveur de l’acide palmitique (C16:0) qui augmente de 20 à 24%. L’analyse de la composition en acides aminés par HPLC a permis l’identification de 17 acides aminés dont 8 essentiels (His, Mét, Ile, Leu, Lys, Thr, Val, Phe). [less ▲]

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See detailSalinity impact on seed yield, polyphenols composition and antioxidant activity of Fennel (Foeniculum vulgarae Mill) extracts
Bettaieb Rebey, Ines; Bourgou, S.; Msaada, K. et al

Poster (2017, April 24)

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See detailEtude de la composition chimique et de l’activité antioxydante des différents extraits de la Lavande dentée (Lavandula dentata)
Bettaieb Rebey, I.; Bourgou, S.; Saidani Tounsi, M. et al

in Journal of New Sciences Agri & Biotech (2017), 39(2), 2096-2105

In this study, Lavandula dentata organs (roots, stems and leaves) were investigated for their essential oils, total phenolics, flavonoids contents and antioxidant activities. Essential oil yields were 0 ... [more ▼]

In this study, Lavandula dentata organs (roots, stems and leaves) were investigated for their essential oils, total phenolics, flavonoids contents and antioxidant activities. Essential oil yields were 0.22% in roots, 0.68 % in stems and 0.89 % in flowers. Major components of the oils were β-ocimene, limonene and 1,8 cineol in roots, stems and leaves and flowers, respectively. In all organs, total phenolics content ranged from 42.57 to 16.17 mg gallic acid equivalents per gram of dry weight (mg GAE/g DW).The antioxidant activities of Lavandula dentata extracts obtained from the three organs were assessed using two tests (DPPH and reducing power). The root extract was strongly effective as DPPH radical scavenger and reducing agent. Thus, the identification of individual target polyphenolic compounds of roots was performed by RP-HPLC. The major phenolic compound detected in roots was rosmarinic acid. This activity was high enough for the plant to be a new and natural source of strongly antioxidant substances for use as natural additives in food and pharmaceutical industry. [less ▲]

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See detailUse of complementary biophysical approaches to study the interactions of fatty acid hydroperoxides with biomimetic plant plasma membranes
Deboever, Estelle ULg; Nasir, Mehmet Nail ULg; Deleu, Magali ULg et al

Poster (2017, January 20)

In the actual context, biopesticides have emerged as a main alternative to conventional agriculture1. Hence, elicitors are metabolites naturally produced by microorganisms, pathogenic or not, and plants ... [more ▼]

In the actual context, biopesticides have emerged as a main alternative to conventional agriculture1. Hence, elicitors are metabolites naturally produced by microorganisms, pathogenic or not, and plants which are able to induce the natural resistance of plants. Also, they have proved to be excellent candidates for biological control. In this context, the lipoxygenase pathway leads to the formation of fatty acid degradation products, called oxylipins, which appear to be crucial agents in plant defence mechanisms2,3. Moreover, with their broad spectrum of action and their possible inducibility, oxylipins appear to be promising candidates for their use as elicitors4. This work focuses on two hydroperoxy-derived oxylipins, the 13(S)-hydroperoxy-octadecadienoic acid (13-HPOD) and the 13(S)-hydroperoxy-octadecatrienoic acid (13-HPOT). The study of the interaction of such compounds with representative plant plasma membrane lipids is essential to understand plant resistance mechanisms. Several in silico and experimental techniques of biophysics showed that acyl-hydroperoxides have significant adsorption capacity and a strong affinity for model membranes. They may also penetrate biological membrane but no permeabilisation effect was observed in this work. Slight conformational differences seem to have a significant impact on their ability to interact with plant plasma membranes. Based on these results, further investigation of the interactions of fatty acids hydroperoxides, even more on the 9-forms, with plant plasma membranes and eventually in the presence of phytopathogenic species, would allow a better understanding of the innate immunity and, on the longer term, could lead to the development of new elicitors with biological mechanisms potentially independent of membrane protein receptors. [less ▲]

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See detailChemical composition, acute toxicity, antimicrobial and anti-inflammatory activities of Thymus fontanesii essential oil from Algeria
Sidali, Lamia; Brada, Mousa; Fauconnier, Marie-Laure ULg et al

in PhytoChem & BioSub Journal (2017), 11(1), 11

The aim of the present study was to determine the chemical composition and to evaluate the acute toxicity, antimicrobial and anti-inflammatory activities of Thymus fontanesii essential oils (TFEO). The ... [more ▼]

The aim of the present study was to determine the chemical composition and to evaluate the acute toxicity, antimicrobial and anti-inflammatory activities of Thymus fontanesii essential oils (TFEO). The oils were obtained by hydrodistillation from the aerial parts of T. fontanesii at yield of 2.4±0.2%. Using GC and GC/MS techniques, 24 compounds were identified representing more than 98% of the oil composition. The main constituents were carvacrol (54.7±1.2%), p-cymene (17.5±0.3%) and ɣ-terpinene (8.8±0.6%). Using the disc diffusion and broth microdilution methods against six microbial strains, the antimicrobial evaluation showed that TFEO exhibited good antibacterial activity against all the strains tested except Pseudomonas aeruginosa. The acute toxicity test of TFEO was conducted in mice by gavage in single doses of 100-3000 mg/kg. However, the mortality rate as well as the acute toxicity of the oral administered oil increased progressively with increasing dose (LD50=875mg/kg). Anti-inflammatory activity of TFEO was evaluated using carrageenaninduced paw edema in mice. The paw edema was reduced by the TFEO at doses of 50 mg/kg (22.8%) and 100 mg/kg (62.2%). The TFEO was found to possess potent anti-inflammatory activity.Results of the present study indicate that TFEO has a noteworthy potential for the use in pharmaceutical formulations. [less ▲]

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See detailChemical composition of essential oils and hydrosols of three Eucalyptus species from Senegal: Eucalyptus alba Renv, Eucalyptus camaldulensis Dehnh and Eucalyptus tereticornis Hook
Barka Ndiaye, El Hadji; Talla Gueye, Momar; Ndiaye, Ibrahima et al

in American Journal of Essential Oils and Natural Products (2017), 5(1), 1-7

The leaves of three eucalyptus species Eucalyptus Alba, Eucalyptus camaldulensis and ucalyptus tereticornis were collected in Kaolack (Senegal) and were extracted by steam distillation after 3, 7, 14 and ... [more ▼]

The leaves of three eucalyptus species Eucalyptus Alba, Eucalyptus camaldulensis and ucalyptus tereticornis were collected in Kaolack (Senegal) and were extracted by steam distillation after 3, 7, 14 and 21 days of drying. The volatile components of aqueous distillates (hydrosols) were obtained by liquid–liquid extraction using n-hexane. The different extracts were analyzed by gas chromatography coupled to a flame ionization detector (GC-FID) and by gas chromatography coupled to a mass spectrometer (GC-MS). Essential oils yields obtained range from 0.3 to 1.6%. E. camaldulensis had the higher yield. Forty four compounds were characterized in E. camaldulensis essential oils. These lasts were dominated by 1.8-cineole (47.54 to 52.47%), limonene (16.5 to 19.1%), α-pinene (7.3 to 11.2%) and p-cymene (6.0 to 8.8%). Fifty compounds were identified in E. Alba oils with 1.8-cineole (36.0-38.3%) α-pinene (19.0-26.4%), limonene (5.7- 8.3%), trans-pinocarveol (3.5 -5.0%) β-pinene (1.9 to 4.6%) as major compounds. In E. tereticornis oils, fifty two compounds were identified. Their composition were dominated by p-cymene (42.49 to 48.51%) followed by 1.8-cineole (21.3- 24.5%), limonene (4.8- 5.9%) and α-pinene (1.9 to 6.7%). The analyzed hydrosols were composed by oxygenated molecules whose major part was found in oils. As essential oils, all corresponding hydrosols hade high rate of 1.8-cineole. E. alba hydrosol contains mainly 1.8-cineole (39.1%), trans-pinocarveol (19.3%), pinocarvone (6.8%). E. camaldulensis hydrosol was dominated by 1.8-cineole (52.6%), α-terpineol (6.6%), cis-p-mentha-1-(7)-8-dien-2ol (5.1%). The major compounds of E. tereticornis hydrolat were: 1.8-cineole (30.7%), α-terpineol (8.8%), trans-pinocarveol (7.6%), carvacrol (7.0%). The results showed that although 1.8-cineole was the main component of the hydrosols of all eucalyptus species, but its relative content was higher in E. camaldulensis. [less ▲]

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See detailFlavor profiles of monovarietal virgin olive oils produced in the Oriental region of Morocco
Mansouri, Farid; Ben Moumen, Abdessamad; Richard, Gaetan ULg et al

in Oilseeds and fats, Crops and Lipids (2017), 24

The purpose of this study is the evaluation of flavor profiles of monovarietal virgin olive oils (VOO) produced in the Oriental region of Morocco via the characterization of volatile compounds, using SPME ... [more ▼]

The purpose of this study is the evaluation of flavor profiles of monovarietal virgin olive oils (VOO) produced in the Oriental region of Morocco via the characterization of volatile compounds, using SPME-GC/MS technique, and the determination of total phenolic content (colorimetric method). The study concerns oils of three European olive cultivars (Arbosana, Arbequina and Koroneiki) which were recently introduced in Morocco under irrigated high-density plantation system. GC/MS aroma profiles of analyzed VOOs showed the presence of 35 volatile compounds. The major compounds in such oils are C6 compounds produced from linoleic and linolenic acids via lipoxygenase pathway such as trans-2-hexenal, cis-2-hexenal, cis-3-hexen-1-ol, trans-3-hexen-1-ol, trans-3-hexen-1-ol acetate, hexanal and 1-hexanol in different proportions depending on the cultivar (p<0.05). In addition, statistical analyses indicate that the analyzed VOOs have different aroma profiles. Arbequina oil has a high proportion of compounds with sensory notes “green” and “sweet” giving it a fruity sensation compared to Arbosana and Koroneiki. In parallel, Arbosana and Koroneiki oils are rich in phenolic compounds and provide relatively bitter and pungent tastes to these oils. [less ▲]

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See detailPhytotoxic activity and chemical composition of Cassia absus seeds and aerial parts
Zribi, Ines; Sbai, H.; Ghezal, N. et al

in Natural Product Research (2017)

The present study was conducted to assess the phytotoxic potential and the phytochemical composition of Cassia absus. Aqueous extracts caused significant reduction of root growth of Lactuca sativa. Seed ... [more ▼]

The present study was conducted to assess the phytotoxic potential and the phytochemical composition of Cassia absus. Aqueous extracts caused significant reduction of root growth of Lactuca sativa. Seed extract was more effective than aerial part extract. Successive extractions of this plant were performed using solvents with increasing polarities. The methanolic seed extract exerted strong phytotoxic effect on seedling growth, followed by petroleum ether extract of the aerial part. The phytochemical investigation showed that among the organic extracts, methanol extracts of seeds and aerial parts contained the highest amounts of total phenolics and proanthocyanidins. Seeds were rich in linoleic acid followed by palmitic acids. Palmitic, stearic and arachidic acids were the major fatty acids in aerial parts. HPLC-DAD analysis of the methanolic extracts revealed the presence of luteolin in C. absus aerial parts. [less ▲]

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See detailMethanol emissions from maize: Ontogenetic dependence to varying light conditions and guttation as an additional factor constraining the flux
Mozaffar, Ahsan ULg; Schoon, N.; Digrado, Anthony ULg et al

in Atmospheric Environment (2017), 152

Because of its high abundance and long lifetime compared to other volatile organic compounds in the atmosphere, methanol (CH3OH) plays an important role in atmospheric chemistry. Even though agricultural ... [more ▼]

Because of its high abundance and long lifetime compared to other volatile organic compounds in the atmosphere, methanol (CH3OH) plays an important role in atmospheric chemistry. Even though agricultural crops are believed to be a large source of methanol, emission inventories from those crop ecosystems are still scarce and little information is available concerning the driving mechanisms for methanol production and emission at different developmental stages of the plants/leaves. This study focuses on methanol emissions from Zea mays L. (maize), which is vastly cultivated throughout the world. Flux measurements have been performed on young plants, almost fully grown leaves and fully grown leaves, enclosed in dynamic flow-through enclosures in a temperature and light-controlled environmental chamber. Strong differences in the response of methanol emissions to variations in PPFD (Photosynthetic Photon Flux Density) were noticed between the young plants, almost fully grown and fully grown leaves. Moreover, young maize plants showed strong emission peaks following light/dark transitions, for which guttation can be put forward as a hypothetical pathway. Young plants’ average daily methanol fluxes exceeded by a factor of 17 those of almost fully grown and fully grown leaves when expressed per leaf area. Absolute flux values were found to be smaller than those reported in the literature, but in fair agreement with recent ecosystem scale flux measurements above a maize field of the same variety as used in this study. [less ▲]

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