Agronomy

Pour rechercher la variabilité morphologique intra-et inter-populations de Pistacia atlantica Desf., une étude portant sur huit populations spontanées d'Algérie a été effectuée. Cette étude comprend une partie biométrique des feuilles et fruits complétée par une étude descriptive macro-et micro-morphologique. L'analyse de la variance ainsi que la comparaison des moyennes des caractères morphologiques étudiés ont révélé une diversité importante à l'intérieur et entre les différentes provenances correspondant à des bioclimats différents. L'analyse multivariée a permis, par la suite, la séparation de ces provenances en quatre groupes à partir des variables discriminantes de dimensions de la feuille et de la foliole terminale, le nombre de paires de folioles, les ailes foliaires, l'odeur de la feuille, la couleur de la feuille, la taille de la foliole terminale ainsi que la forme de son apex et enfin la couleur et la forme du fruit. L'analyse des résultats obtenus met en évidence l'originalité des populations algériennes par rapport à celles communément décrites pour cette espèce dans la littérature, notamment par l'occurrence de cire sur les feuilles. La variabilité morphologique de cette espèce en Algérie peut être due aux conditions écologiques, et les mécanismes physiologiques impliqués sont discutés dans cet article.

Little is known about the morphological variations or differences in stomatal characteristics of Pistacia species. How these variations may be related to the environment is also unknown. This paper describes the diverse stomatal morphology recorded among the Algerian representatives of Pistacia atlantica Desf. (Atlas pistachio). Leaf Samples of eight Algerian sites of Pistacia atlantica were characterised according to their stomatal type, distribution and position in the epidermis, shape, size and density by the mean of light microscopy and scanning electron microscopy. The leaves are amphistomatic in all the sites. However the abaxial stomatal densities are much higher. The mean number of stomata per square millimetre was 30.5 on the adaxial face and 308.5 on the abaxial face. The stomata were elliptical and slightly sunkun in the epidermis, of the actinocytic or anomocytic types with a mean length of 29.1µm and a mean width of 19.5µm. However, the variations in the aperture of stomata did not reveal a clear pattern in response to the ecological gradient tested, suggesting that it is a genotypic character. Only, the stomatal density showed agreement with the environmental conditions for the areas where the trees were grown. Especially up to 900 m in altitude ecological conditions abaxial leaf stomata density decreases significantly compared to that of lowland habitats. The best discriminating traits recorded in this study were the stomata size and the stomatal density. These characteristics may afford an initial screening method for classifying P. atlantica in terms of drought resistance.

SUMMARY - "Current state and degradation of the Algerian pistachio orchards". Pistacia atlantica is widespread in South Algeria (semi-arid and arid regions). It can grow and stand strong winds and long periods of drought. The main factors that contribute to its degradation are wood exploitation, forest fires and animal action. The seeds called ElKhodiri by the local population are used

To study the morphological variability within and among Pistacia atlantica Desf. populations, a comparative analysis was undertaken in eight wild populations grown under different climatic conditions in Algeria. This study addresses the morpho-biometrical aspect of the leaves and the fruits, as well as the micromorphological aspect of leaves. ANOVA as well as mean comparison of the morphological traits revealed a significant diversity within and among the populations. Furthermore, in the multivariate analysis, the populations were separated into four different groups through the discriminating variables: leaf and leaflet dimensions, number of pairs of leaflets, leaf wings, leaf smell and colour, terminal leaflet size and apex, and finally fruit colour and shape. These results showed the originality of the Algerian populations as compared with those commonly described for this species in the literature, in particular by the occurrence of wax on the leaves. The morphological variabili...

The root environment is characteristic for each species, soil type and environmental condition. Interactions may be established between the roots and its environment, which influences the mineral nutrition and the relationship soil / plant. The importance of environmental characterization of Atlas pistachio root rhizosphere under arid climate is our primary objective in this work. The knowledge of the arid climates and their water and soil resources, that lead to vegetation in severe conditions, suggests the implementation of serious measures in plantations development in drylands. Our results confirmed these assumptions and re vealed the presence and the extent of poor soils in these regions likely with arido-soils type, unsalty, limestone with very low organic matter content and low phosphorus rates. The richness of these soils in nitrogen, especially their rhizospheric fraction, may be explained by the root activity and the microbial biomass in the soil / root interface.

1 Département d’Agronomie, Faculté S.N.V. Université « Ziane Achour », Djelfa 17000, Algérie. E-mails: [email protected]; [email protected] 2 Laboratoire de Biosystématique végétale, Faculté des Sciences Agronomiques et Biologiques. Université de Mouloud Mammeri, Tizi-Ouzou 15000, Algérie. E-mail: [email protected] 3 Equipe Diversité et Fonctionnement : des Molécules aux Ecosystèmes. Institut Méditerranéen de Biodiversité et d’Écologie (IMBE) – UMR CNRS 7263/IRD 237. Aix-Marseille Université, Centre Saint-Charles – Marseille, France. Emails: [email protected]; [email protected] 4 Aix-Marseille Université, Centrale Marseille, CNRS, Fédération Sciences Chimiques Marseille (FR 1739)-PRATIM, 13000, Marseille, France. E-mails: [email protected]; [email protected]. * Auteur pour la correspondance

Pistacia lentiscus (mastic tree) is very common in the Mediterranean region. In Algeria, Mastic tree is distributed in a wide range of habitats along the climatic gradient. We studied the factors that may shape its morphological, physiological, and genetic differentiation. For this purpose, we analyzed the morphological variability intra-population between male and female individuals of Pistacia lentiscus, by using leaf characters. In total, se ven quantitative morphological variables were measured for the leaves. The statistical analysis (PCA), showed significant differences for the measured variables between male and female plants of Pistacia lentiscus.

Grâce a son systeme racinaire tres puissant, le Pistachier de l'Atlas joue un role important contre l'erosion des sols et dans la lutte contre la desertification qui menace constamment les regions arides et sahariennes. On se propose ici d'etudier la variation des parametres de mycorhization (frequence de mycorhization, intensite de colonisation, teneur arbusculaire et vesiculaire) en fonction des saisons et des stations (caracterisees par leur bioclimats), afin de mieux cerner les conditions de l'etablissement de la symbiose chez cette espece. Les proprietes physico-chimiques (pH, conductivite electrique, matiere organique et calcaire total) des sols ont ete determinees pour cinq sites d'echantillonnage. Des spores de champignons recoltees dans la rhizosphere de l'espece etudiee ont fait l'objet d'une identification morphologique afin de mesurer la diversite des especes de champignons mycorhiziens. Les observations microscopiques des racines ont reve...

Description of the subject: The use of synthetic antioxidant molecules is currently being a health issue because of their potential toxicological risks. Now, several researches on plants as new sources of natural antioxidants are being developed. Objective: For this purpose we were interested to study the antioxidant activity of methanolic extracts of a plant from the Algerian flora: Pistacia lentiscus. Methods: Methanolic extracts were prepared from both parts of the plant (leaves and/ or fruits). The quantitative estimation of the total phenols, flavonoids and tannins content present in the extracts was carried out by colorimetric methods. The antioxidant proprieties of the extracts were performed using two methods: DPPH (2, 2-diphenyl-1-picrylhydrazil) free radical scavenging activity and the ferric reducing power (FRAP). Results: Colorimetric assays showed that the methanolic extracts of leaves and /or fruits contain high amounts of total phenols, tannins and less amounts of fla...

Our study goal is to ascertain the effects of Juniperus phoenicea seed passage, through potential frugivores' digestive tubes, on their germination behavior in the central Saharan Atlas of Algeria. The methodology adopted entails comparing germination findings of ingested seeds of Juniperus phoenicea by the frugivores, in this case: Ring Ouzels, Wild Boar, Common Genet, Golden Wolf of Africa, red fox, and Shaw's Jird to those of seeds not ingested. The main findings demonstrate that frugivores' ingestion of Juniperus phoenicea seeds does not favorably affect their germination rates. Nonetheless, the seeds ingested by Ring Ouzels provide close results to those of the control, which oscillate by 60%. Also, a notable decrease has been recorded in the batches of the wild boar and the carnivores. The five (05) batches of Shaw's Jird, on the other hand, show a low to no germination rate. Furthermore, a significant modification of Juniperus phoenicea germination pattern is observed after the ingestion of the seeds; not only delaying the latent germination time by a few days but also slowing down the speed of germination. These alterations are unique to each frugivores and such diversity may have a favorable impact on the effectiveness of Juniperus phoenicea dispersal.