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Ferdaous Guasmi Walid Elfalleh Hédia Hannachi Khadija Fères Leila Touil Nidhal Marzougui 《Journal of plant nutrition》2013,36(5):836-847
This study describes the effect of some parameters on anther culture of barley to optimize the plant regeneration condition of this species. The embryo formation and plant regeneration from anthers of three barley cultivars (‘Igri’, ‘Saida’ and ‘Libya’) were investigated. The effects of length of flag leaves, stage of microspore development, and pre-treatments (mannitol or cold pre-treatment) of anthers were investigated. Results showed significant responses. Anthers at the mid uninucleate to mid-late uninucleate stage gave the best anther culture response showing 80, 60, and 30% anther development in ‘Igri’, ‘Saida’ and ‘Libya’ barley cultivars, respectively. The use of mannitol (0.3 M) or 20 days cold pre-treatments showed the best results for embryo and green-plant production. 相似文献
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Salsabil Marzougui Gerhard Sch?fer Lotfi Dridi 《Water, air, and soil pollution》2012,223(9):5817-5840
This study focuses on a detailed analysis of the errors introduced by two quasi-analytical approaches based on either Fick??s first law or a combination of Fick??s and Darcy??s laws to evaluate the vapour flux of chlorinated solvents from a source zone located in the unsaturated zone towards the atmosphere. A coupled one-dimensional numerical flow and transport model was developed and applied to three case studies characterised by different water content profiles in the vadose zone and under different levels of maximum dense nonaqueous-phase liquid vapour concentrations and vapour pressure conditions of the source zone. The steady-state concentration and pressure profiles obtained were then used in the two quasi-analytical approaches to estimate the flux towards the atmosphere. When mass fluxes due to density-driven advection become dominant and the vertical advective mass fluxes are increased due to strong pressure gradients in the soil air, the error was observed to increase when using the pure diffusion approach in the quantification of the surface flux calculated by the numerical model with increasing dimensionless Rayleigh numbers. Without taking into account the advective transport in the approach, the relative error calculated with only Fick??s law overestimates the real vapour flux when density-driven advection is dominant and underestimates it when pressure-gradient-driven advection dominates. The more advanced advective?Cdiffusive quasi-analytical approach fits reasonably well with the numerically obtained mass fluxes except near soil layer discontinuities, where the evaluation of both the concentration gradient and pressure gradient in the porous media as well as the determination of the average effective diffusion coefficients are rendered more difficult. 相似文献
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Nadia Ben Brahim Amel Salhi Nidhal Chtourou Daniel Combes Mohamed Marrakchi 《Genetic Resources and Crop Evolution》2002,49(4):429-438
Isozyme variation and phylogenetic relationships between ten annual andperennial Lathyrus species: L.aphaca, L.articulatus, L.cicera, L.hirsutus, L.latifolius, L.nissolia, L.odoratus, L.ochrus, L.sativus and L.sylvestris were studied. Four enzyme systems,leucine-amino-peptidase (LAP), 6-phosphogluconatedeshydrogenase (6-PGD), glutamateoxalo-acetate transaminase (GOT) and phosphoglucoisomerase(PGI) were analyzed, using gel electrophoresis. Fivepolymorphic loci were detected and eleven alleles were identified at these loci.Zymogram data revealed that almost all-present species studied exhibited isozymepolymorphism. L. latifolius andL. sylvestris maintain high levels ofisozyme diversity, which is probably associated with the perenniality of thesetwo species and their predominantly outcrossing reproduction system. Incontrast, the low level of genetic diversity observed in other species isattributed to their breeding systems. These species are annuals and have higherproportions of selfing. The distribution of genetic variation within and amongspecies showed large genetic differences between the analysed species.PGD-1 andPGD-2 loci contributed the most to thedistinction between species. GOT-2,LAP-1 and PGI-1loci contributed to the distinction within species. The low level of gene flowrevealed could be partly related to the high level of autogamy in the majorityof species. The regroupement of species revealed by Nei's genetic similarityagrees only in parte with Kupicha's classification based on morphologicalcharacters. Thus, these isozymic markers are important in germplasm collectionand conservation. 相似文献
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Salem N Msaada K Hamdaoui G Limam F Marzouk B 《Journal of agricultural and food chemistry》2011,59(9):4455-4463
This work was aimed to study the effect of extraction solvent system with varying polarities on polyphenol, flavonoid and proanthocyanidin contents and DPPH scavenging activity. Obtained results showed that phenolic contents and antioxidant activities varied considerably as function of solvent polarity. The extraction with acetone/water (2:8) showed the highest flower polyphenol content (15.09 mg GAE/g DW). Moreover, antiradical capacities against DPPH, chelating power and lipid peroxidation assay were maximal in acetone/water (2:8) of flower extract. Significant variation in antioxidant properties was observed between different development stages of Carthamus tinctorius flowers; the highest antioxidant activity was observed at stage III (full flowering) while phenolic composition reached its maximum at stage II (flower formation). Gallic acid was the most abundant phenolic compound in C. tinctorius orange flowers, accounting for about 102.57 (μg/g DW). Findings underline the potential health benefits as a result of consuming C. tinctorius flowers and suggest that it could be used as valuable flavor with functional properties for food or nutraceutical products on the basis of the high polyphenol contents and antioxidant activities. 相似文献
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Amel Bouzidi Noureddine Baaka Nidhal Salem Mohamed Farouk Mhenni Zine Mighri 《Fibers and Polymers》2016,17(8):1256-1261
In the present study, an attempt has been made to dye the wool fabric with Limoniastrum monopetalum stems, as a source of natural dye, which has not been exploited so far. Optimization of extraction parameters was done. Optimum results of extraction process were obtained with a dye concentration of 60 g/l, a temperature of 90 °C during 100 min. The study of different factors effecting dyeability of wool fabrics by aqueous L. monopetalum stems extract showed that the pH of dye bath and dyeing temperature and time affected considerably the color yield. The best results were obtained at the following conditions; pH 2, 100 °C, and 60 min. Metal mordants, when used in conjunction with L. monopetalum dye, allowed to obtain various shades. The determination of phenolic contents of aqueous L. monopetalum stems extract showed a high amount of phenolic components. Based on RP-HPLC, the coloring extract of L. monopetalum stems contains tannins and polyphenols. The major identified phenolic compounds were procatechuic, Trans-cinnamic and gallic acids. Hence, aqueous L. monopetalum stems extract could be successfully exploited for dyeing wool fabrics with high color yield (K/S). 相似文献
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