Chaouki Al Faiz

Chemical Polymorphism of Origanum compactum Grown in All Natural Habitats in Morocco

Origanum compactum L. (Lamiaceae) is one of the most important medicinal species in term of ethnobotany in Morocco. It is considered as a very threatened species as it is heavily exploited. Its domestication remains the most efficient way to safeguard it for future generations. For this purpose, wide evaluation of the existing variability in all over the Moroccan territory is required. The essential oils of 527 individual plants belonging to 88 populations collected from the whole distribution area of the species in Morocco were analyzed by GC/MS. The dominant constituents were carvacrol (0 – 96.3%), thymol (0 – 80.7%), p‐cymene (0.2 – 58.6%), γ‐terpinene (0 – 35.2%), carvacryl methyl ether (0 – 36.2%), and α‐terpineol (0 – 25.8%). While in the Middle Atlas region and the Central Morocco mainly carvacrol type samples were found, much higher chemotypic diversity was encountered within samples from the north part of Morocco (occidental and central Rif regions). The high chemical polymorphism of plants offers a wide range for selection of valuable chemotypes, as a part of breeding and domestication programs of this threatened species.

Evaluation of Drought Tolerance Variability in Mediterranean Alfalfa Cultivars in the Field Under Moroccan Conditions

Sixteen alfalfa cultivars originating from the Mediterranean basin were tested in an experimental station in Morocco, located in the semi arid bioclimatic area. This research was conducted in PERMED project during 2006–2008 and aimed to evaluate the adaptation of cultivars to drought stress. The trial was conducted under two irrigation treatments. The first treatment was normally irrigated by providing an amount of water corresponding to the potential evapotranspiration of the crop and in the second treatment with water deficit which was applied by stopping the irrigation during 9 weeks in summer. Results showed that water stress during summer significantly reduced aerial biomass of all cultivars. This reduction varied between 25 and 41% according to cultivars in comparison with a normal irrigated treatment. The difference between cultivars for biomass production was significant only in stress treatment (P< 0.001 with 15 df). Some cultivars showed high forage yield potential, mainly Ameristand, ABT 805, Sardi10, Siriver, Gabes-2355, Rich2, and Erfoud1 even in presence of stress. In the end of August (before restart of irrigation for treatment with suspended summer irrigation), the mean rate of leaf senescence of cultivars was 84% with no significant difference between cultivars. The row cover estimated in the end of summer of the third year varied between 12 and 40% according to the cultivars. Cultivars Gabes-2355, Ameristand and ABT805 showed a smaller number of dead plants under water stress. Therefore, those cultivars could be used by local farmers in this region.

Influence of Environmental Factors on Essential Oil Variability in Origanum compactum Benth. Growing Wild in Morocco

The present study aimed to evaluate the influence of environmental factors on essential oils (EOs) composition of Origanum compactum populations sampled all over the distribution area of the species in Morocco, and to determine the extent of the chemical profiles throughout the geographical distribution of the species. The chemical compositions were submitted to canonical correlation analysis and canonical discriminant analysis that indicated a significant relationship between oil components and some environmental factors. According to their chemical composition and edapho‐climatic characteristics, two major groups of populations were differentiated. The first group was composed of samples growing in regions with humid climate, clayey, sandy, and alkaline soils. These samples showed high thymol, α‐terpineol, linalool, and carvacryl methyl oxide content. The second group consisted of plants belonging to semi‐arid climate, and growing at high altitudes and silty soils. These samples were characterized by high carvacrol, α‐thujene, α‐terpinene, and myrcene content. However, populations exposed to sub‐humid climate, appeared less homogeneous and belong mainly either to the first or second group. A significant correlation between some edaphic factors (pH, K2O content, soil texture) and the EOs yield of O. compactum plants was evidenced. In spite of the correlation obtained for the oil composition with edapho‐climatic factors and the variance explained by the environmental data set, the observed EO diversity might be also genetically determined.

Drought Survival of Some Perennial Grasses in Moroccan Rainfed Conditions: Agronomic Traits

A 4 year experiment was carried out to evaluate perenniality and some adaptive responses to drought of Dactylis glomerata, Festuca arundinacea and Phalaris aquatica, within the multi-site activity of the EU-PERMED project. The trial held in Merchouch experimental INRA station at 68 km west of Rabat/Morocco, in a vertic deep silty clay soil (> 1 m 80 deep) was sown on 20 October 2005 to compare 16 grass accessions. Measurements included: sward establishment, dry matter production, average row cover, sward senescence and phenology. Plant emergence and establishment were good and regular for almost all cultivars. In all seasons, fescue yielded significantly more than cocksfoot. The harsh conditions and summer droughts have affected significantly production and persistence of grasses, mostly cocksfoot cultivars which disappeared completely at the end of the third year except the summer dormant cultivar Kasbah. Four groups of grass cultivars have been distinguished according to their persistence under extreme drought conditions.

Genome size and chromosome number for six taxa of Origanum genus from Morocco

Abstract The majority of the Origanum species are important medicinal plants as well as culinary herbs and have thus a great economic value. Some taxonomic issues are still pending within the genus and the cytogenetic studies about this genus are still very scarce. Therefore, studies concerning chromosome number and genome size can provide complementary data that may be useful to characterize the genus Origanum. These two approaches have been used to characterize five Moroccan taxa of the genus Origanum occurring in the wild in addition to the exotic species O. onites. All investigated taxa are diploid with chromosome number of 2n = 30. This is the first time the chromosome numbers have been counted in O. grosii, O. compactum and O. × font-queri as well as in O. vulgare subsp. virens from Morocco. The genome sizes are considered as small, and the mean values ranged from 1.43 pg/2C in O. vulgare subsp. virens to 1.53 pg/2C in O. compactum. Besides, no significant intraspecific variability in genome size was observed among populations of O. elongatum as well as of O. grosii.

Agronomic Evaluation of Moroccan Ecotypes of Tall Fescue

Drought or reduced water availability is the main factor limiting crop production in Mediterranean area. The aim of this study was to select ecotypes of Festuca arundinacea Schreb. adapted to the Moroccan environment. During 3 years, eleven ecotypes of tall fescue, collected from different regions of Morocco, and eight commercial cultivars were evaluated for the following agronomical traits: dry matter yield, summer growth, heading date, survival rate, leaf area index (LAI) and plant height.