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In the present study, we tested the effect of amino acids on secondary somatic embryogenesis of Moroccan cork oak (Quercus suber L.). Secondary mature and immature somatic embryos were obtained from primary somatic embryos cultured in N30K medium supplemented with nineteen amino acids. Stimulation of embryogenesis was dependent on the type and concentration of amino acid in the medium. Thus, L-glutamine and L-asparagine at 3.42 mM have been proved to be the most favorable for the formation of functional somatic embryos and the induction of secondary somatic embryos.

Adventitious budding from embryonic cotyledons of immature seeds of carob was obtained. The combination of BAP (4.44 μM) and NAA (1.5 μM) furthered the neoformation of adventitious buds. These latter were multiplied on MS medium added with BAP (2.22 μM). Stems and leaves growing were improved by adding 2.02 μM GA3. Elongation was favored by 0.5 μM NAA. 70% of rooting was obtained with 10 μM IBA.

International audience; Carob (Ceratonia siliqua L.) fruit pulp from 12 wild and 8 domesticated trees from 15 Moroccan localities were investigated for their polyphenols contents: total polyphenols content (53.22 - 118.04 mg and 57.46 - 183.31 mg), total flavonoids (1.41 - 4.83 mg and 1.62 - 7.46 mg) and condensed tannins (1.47 - 7.36 mg and 1.85 - 6.66 mg) in one carob fresh pulp for wild and domesticated trees, respectively. Fruit pulp from trees in the same region shows variable contents in polyphenols, flavonoids and condensed tannins.

We study the production of polyphenols by callus cultures from two cultivars of cotton (Gossypium hirsutum L.). Coker 312 produces the best calli and has embryogenic potential contrary to that of R405-2000, which is non- embryogenic. There is a relationship between the level of phenolic compounds and the callus cultures. Callogenesis in Coker 312 is highly correlated to a higher content of catechin, caffeic acid, ferulic acid, rutin, o—coumaric acid and salicylic acid. On the other hand, the cinnamic acid derivates (trans-cinnamic, cis and trans—methoxycinnamic acids) found in high amounts in R405-2000 calli could have a negative influence on the induction of cotton callogenesis.

The effect of eucalyptus, rosemary and mugwort essential oils was evaluated on the mycelial growth and toxigenesis of Penicillium aurantiogriseum and P. viridicatum. A significant decrease in mycelial dry weight was obtained with the addition of 0.05–2.5% of each of the three essential oils in yeast extract sucrose broth. The inhibition of mycelium growth was tested on malt extract agar, Czapeck yeast agar, yeast extract sucrose agar and broth at constant pH, and was highly effective for mugwort, followed by eucalyptus. A complete inhibition of toxin production was observed with 0.44% of each essential oil for P. aurantiogriseum and 0.22% for P. viridicatum.

The in vitro regeneration from cork oak axillary buds was investigated. Different macronutrient formulas supplemented with MS micronutrients, vitamins and 3% sucrose were tested on shoot multiplication and rooting phases. The WPM macronutrients improved caulogenesis and shoot multiplication. Rooting was achieved on WPM 1/2 macronutrients. Dipping the base of the shoots in an IBA concentrated solution improved the rooting phase. 92% of the rooted plants were successfully potted on horticultural substrate with a high relative humidity.

To improve the in vitro germination and development of cork oak embryonic axes, several mineral media were tested; Durzan medium modified 1/2 supplemented with 400 mg/l glutamine and 3% sucrose gave the best results. The action of BA alone or combined with other growth regulators was also studied. A low concentration (0.44 μM) was found to give an acceptable percentage of plantlets. When combined with NAA, callogenesis was observed. The transfer of cultures in conditions of low luminosity led to the formation of several axillary buds. These buds were multiplied on a solid medium supplemented with GA3 at low concentration. The buds were elongated, then rooted on a growth regulator-free medium after brief dipping in an auxinic solution. The rooted plants were potted on horticultural substrate.

A total of 321 bacterial strains were isolated from the rhizosphere of healthy strawberry ( Fragaria X ananassa Duch.) plants harvested from different places in Zlaoula area (Larache, Morocco). They were screened by dual testing for in vitro antagonism towards Botrytis cinerea (Bt7). Nine antagonistic strains were retained. Their effectiveness was evaluated according to temperature (5 to 30°C), pH (4 to 10) and water activity (aw, 0.80 to 1). Low values of water activity and acid pH were unfavourable for the growth inhibition. All the isolates were identified to belong to Bacillus amyloliquefaciens . Key words : Antifungic activity, water activity, Bacillus amyloliquefaciens , Botrytis cinerea , pH, temperature.

The fatty acid composition of photosynthetic tissues from 137 species of gymnosperms belonging to 14 families was determined by gas chromatography. Statistical analysis clearly discriminated four groups. Ginkgoaceae, Cycadaceae, Stangeriaceae, Zamiaceae, Sciadopityaceae, Podocarpaceae, Cephalotaxaceae, Taxaceae, Ephedraceae and Welwitschiaceae are in the first group, while Cupressaceae and Araucariaceae are mainly in the second one. The third and the fourth groups composed of Pinaceae species are characterized by the genera Larix, and Abies and Cedrus, respectively. Principal component and discriminant analyses and divisive hierarchical clustering analysis of the 43 Pinaceae species were also performed. A clear-cut separation of the genera Abies, Larix, and Cedrus from the other Pinaceae was evidenced. In addition, a mass analysis of the two main chloroplastic lipids from 14 gymnosperms was performed. The results point to a great originality in gymnosperms since in several species and contrary to the angiosperms, the amount of digalactosyldiacylglycerol exceeds that of monogalactosyldiacylglycerol.

International audience; Although Glycosyl-Inositol-Phospho-Ceramides (GIPCs) are the main sphingolipids of plant tissues, they remain poorly characterized in term of structures. This lack of information, notably with regard to polar heads, currently hampers the understanding of GIPC functions in biological systems. This situation prompted us to undertake a large scale-analysis of plant GIPCs: 23 plant species chosen in various phylogenetic groups were surveyed for their total GIPC content. GIPCs were extracted and their polar heads were characterized by negative ion MALDI and ESI mass spectrometry. Our data shed light on an unexpected broad diversity of GIPC distributions within Plantae, and the occurrence of yet-unreported GIPC structures in green and red algae. In monocots, GIPCs with three saccharides were apparently found to be major, whereas a series with two saccharides was dominant in Eudicots within a few notable exceptions. In plant cell cultures, GIPC polar heads appeared to bear a higher number of glycan units than in the tissue from which they originate. Perspectives are discussed in term of GIPC metabolism diversity and function of these lipids.

For the first time, pentane extracts of the fruits of Foeniculum vulgare, subspecies piperitum, have been analyzed by GC. Two new compounds, piperitenone and piperitenone oxide, were identified by their mass spectra.

Pentane extracts of the seeds (fruits) of 44 cultivars of parsley have been examined by gas chromatography. The curly-leaved parsley cultivars can be distinguished by their dark brown light mericarps which possess an essential oil rich in monoterpenes, particularly α-pinene (15.7–24.1%) and β-pinene (9.6–15.1%). In root parsley, only α-pinene (10.6%), β-pinene (7.1%), myristicin (2.5%) and apiole (79.8%) were found, while apiole (30.4–67.5%) is the principal constituent of Giant Italian parsley. Myristicin (0.7–62.3%) was present in all parsley specimens analyzed.

Pentane extracts of the seeds (fruits) of 35 cultivars of dill have been examined by GC. From the results obtained, three broad chemotypes could be distinguished by the presence of carvone, and the presence or absence of myristicin and dillapiole. The major components of the cultivars of type 1 was found to be limonene (36.9–46.7%), carvone (17.8–45.6%), myristicin (0.2–20.3%), and dillapiole (8.0–22.3%), whereas in type 2 they were limonene (31.0–40.9%), carvone (25.1–47.4%), and dillapiole (6.3–31.8%). No myristicin was found in the second type. In the third chemotype, neither myristicin nor dillapiole were characterized; instead, limonene (39.5–50.7%) and carvone (43.7–57.7%) were only major constituents. Although chemotype 3(27 cultivars) possessed a chemical composition typical of European dill seed, the oil content was found to vary from 1.75–5.8%.

With 10,700 species distributed in 637 genera, the Rubiaceae family is one of the largest of the angiosperms. Since it was previously evidenced that the fatty acid composition of photosynthetic tissues can be a tool for chemotaxonomic studies, the fatty acid composition of leaves from 107 Rubiaceae species highly representative of the diversity of the family was determined. Principal component analysis allowed a clear-cut separation of Coffeae, Psychotrieae and Rubieae. The occurrence of C16:3 fatty acid, a marker of the prokaryotic plastidial lipid biosynthetic pathway, concerned at least two branches: Theligoneae/Rubieae and Anthospermeae–Anthosperminae which appeared to be in close relationship. Additional experiments were carried out to ensure the correlation between the presence of C16:3 fatty acid and the prokaryotic biosynthetic pathway.