Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
      More Filters
      Clear All
      More Filters
      Source
    • Language
148 result(s) for "Hassan, Mahmoud O"
Sort by:
Application of SRAP Markers to Identify Gender and Species in Genus Ephedra Tourn. ex L
Background: The genus Ephedra (Ephedraceae) is a dioecious gymnosperm, where female individuals produce the pharmacologically active ephedrine alkaloids. Identifying the sex of specimens without reproductive cones is challenging due to their xeromorphic and morphological similarity. The challenges in sex identification complicate conservation and propagation efforts. Methods: Sequence-Related Amplified Polymorphism (SRAP) markers were applied to distinguish genders in five Ephedra species, particularly the vegetative branches, as well as powdered and fragmented specimens. The fresh material for the five studied Ephedra species and two sexes per species (totaling 10 samples; 5 females & 5 males) was collected from Sinai, Egypt. Results: The SRAP marker results revealed an exclusively male-specific band, and this is not applicable in females in the studied species. The applied SRAP markers grouped males and females in different UPGMA clusters and proved their efficiency in distinguishing between males and females in the five studied species. The Polymorphic Information Content (PIC) values are low (0.16–0.38); this suggests moderate genetic diversity between the females of the studied species, reflecting slow evolutionary rates. Conclusions: The SRAP markers are efficient for identifying Ephedra species at the species and gender levels, even in the absence of sex organs and molecular sequences. Recommendation: This study recommends the use of SRAP markers for conserving and propagating female plants for ephedrine production and suggests sequencing a 95 bp male-specific band to determine if it corresponds to a known sex-linked gene.
Anatomical Tool as Additional Approach for Identifying Pharmaceutically Important Ephedra Species (Ephedraceae) at Gender Identity Level in Egypt
The genus Tourn. ex L. (Ephedraceae) is an important source with pharmacological and environmental potential. Conversely, spp. still exhibit taxonomic complexity, especially for the specimens lacking reproductive cones. This complexity is attributed to its xeromorphic features, notably the reduced leaves and analogous assimilating branches, which make the species identification a real challenge. The current study provides a pioneering approach to distinguish fragments of species at the gender level. This study was based on the stem anatomy and stem epidermal features using a light microscope for five species ( Decne., Forssk., Fisch. & C.A.Mey., Forssk. and Boiss.) represented by ten genders collected from S. Sinai, Egypt. Anomocytic and brachyparacytic stomata, tanniniferous idioblasts, annual rings, a terete and furrowed outline, the number and width of tracheids, patches of cortical fibers, unicellular trichomes, druses, solitary crystals, and the activity of interfascicular cambium were among the distinguishing features that were found. Different statistical analyses were applied to explore the diversity at interspecific and intra-generic levels. This study revealed that the stem anatomy was not only an efficient tool for identifying the investigated five species at the species level but also presented a differential key to distinguish between genders and species. In addition, our results indicated that the epidermal features played a critical role in differentiating the studied species at the gender level. This study confirms the efficacy of stem anatomy as an identification approach for the species at the gender level and recommends this approach to identify the fragmented for taxonomical, pharmaceutical, and medical applications.
Assessing the Diversity of Beta vulgaris L. ssp. maritima (Sea Beet) Populations in Egypt
Sea beet (Beta vulgaris L. subsp. maritima (L.) Arcang.) is a wild member of the Amaranthaceae family and a progenitor for all the cultivated beets (Beta vulgaris subsp. vulgaris). It is a source of stress-resistant genes, contributing 21 valuable traits to sugar beet through multiple breeding approaches. Despite its importance, the core morphological diversity of sea beet within the Egyptian Mediterranean coastal region has not yet been thoroughly explored. The field observations indicated notable morphological diversity among sea beet populations. This study investigated the morphological diversity of six sea beet populations along with their associated soil and climatic conditions in their primary habitats. Our morphometric investigations identified two varieties: Beta vulgaris subsp. maritima var. glabra, characterized by glabrous, erect, larger basal leaves, and Beta vulgaris subsp. maritima var. pilosa, distinguished by its hairy, prostrate form with smaller basal leaves. These varieties exhibited differences in their spatial distribution, showing high variations at the inter- and intra-population levels as well as the variety level. Soil parameters significantly influenced population morphological variability, which demonstrated a strong positive correlation with soil organic carbon. Our results highlight the need for precise survey and molecular characterization to secure these potential genetic resources from alteration and loss, especially in coastal habitats that are particularly sensitive to future climate change.
Dense Cover, but Not Allelopathic Potential, of Naturalized Alien Cenchrus echinatus L. Threatens the Native Species in Urban Vegetation
Exotic plants usually exhibit problems for native species where they coexist. This study evaluated the effect of naturalized alien Cenchrus echinatus L. on native plants in urban vegetation. A field trial was conducted to assess the effect of this species on the cover and diversity of the native vegetation. The allelopathic potential of such species was examined. Sites comprising C. echinatus had a lower cover than some native species. Lower floristic diversity was observed at higher densities of this plant. The soil under this plant attained lower N, P, and K contents. This soil had no effect on the germination and growth of native species. It also comprised germinable seeds of some species which were absent from the standing vegetation. Exotic C. echinatus may exert negative effects on the native vegetation of the urban plant communities. A dense cover of this species may inhibit the germination of native species, leading to a reduction in their cover. Reduction in cover and diversity of native species may not be attributed to allelopathy. These results suggest that naturalized C. echinatus may be more competitive than the native ones, particularly at higher densities. Furthermore, it may represent a threat to the native plants in the urban vegetation.
Taxonomic Revision of Genus Ephedra Tourn. ex L. in Egypt with Intra-Gender Diversity in Morphometric Traits and Fatty Acid Composition
The genus Ephedra Tourn. ex L. (Ephedraceae) still exhibits taxonomic complexity that has not yet been resolved. This study aimed to determine the taxonomic identity of the Ephedra species in Egypt and identify the fatty acid profile and its diversity at the gender level as a taxonomic tool for specimens lacking reproductive cones. The current study provides a pioneering approach that distinguishes Ephedra species at the gender level. A total of 120 fresh individuals were collected from 20 locations representing different habitats where Ephedra plants grow in Egypt. In addition, herbarium specimens were deposited in Egyptian herbaria. The studied morphological traits included 30 vegetative characteristics and 72 traits of the reproductive organs of both genders. The fatty acid content was measured using gas–mass chromatography (GC-Mass). The taxonomic revision revealed that the Genus Ephedra was represented in the Egyptian flora by five species, Ephedra alata in section Alatae and E. aphylla, E. ciliata, E. foemina, and E. pachyclada in section Ephedra. South Sinai hosts these five species and represents the center of diversity for this genus in Egypt. The vegetative characteristics were subjected to principal component analysis (PCA), which revealed a distinct separation of the five studied species. Similarly, the cone traits treated by hierarchical clustering revealed intra-gender variations. The taxonomic key was developed based on the morphological traits to distinguish the studied species at the gender level. In total, 51 fatty acids were identified from the studied species and grouped as 18 saturated, 16 monounsaturated, and 17 polyunsaturated fatty acids. In the absence of reproductive cones, the lipid content and fatty acid composition of the vegetative parts displayed significant interspecific and intra-gender variations. Therefore, fatty acids can be used to efficiently identify the studied species when they lack reproductive cones. This study proved the efficacy of a multidisciplinary approach to identify Ephedra species at the gender level and recommends this trend for future studies of this genus.
Heteroblastic Inflorescence of Lamium amplexicaule L. in Egyptian Flora
Lamium amplexicaule L. (Family: Lamiaceae) is a cosmopolitan weed whose eradication is challenging. The phenoplasticity of this species is related to its heteroblastic inflorescence, which has not received adequate research worldwide in its morphological and genetic aspects. This inflorescence hosts two flower types, a cleistogamous (CL: closed flower) and a chasmogamous (CH: opened flower). This species subjected to detailed investigation is a model species to clarify: (1) the existence of the CL and CH flowers in relation to the time and individual plants. (2) the predominant flower morphs in Egypt. (3) the morphological and genetic variability between these morphs. Among the novel data retrieved from this work is the Presence of this species in three distinct morphs coexisting during winter. These morphs showed remarkable phenoplasticity, particularly in flower organs. Significant differences were observed between the three morphs in pollen fertility, nutlets productivity and sculpture, flowering time, and seed viability. These differences were extended to the genetic profile of these three morphs assessed by the inter simple sequence repeats (ISSRs) and start codon targeted (SCoT). This work highlights the urgent need to study the heteroblastic inflorescence of crop weeds to facilitate its eradication.
Dense Cover, but Not Allelopathic Potential, of Naturalized Alien ICenchrus echinatus/I L. Threatens the Native Species in Urban Vegetation
Exotic plants usually exhibit problems for native species where they coexist. This study evaluated the effect of naturalized alien Cenchrus echinatus L. on native plants in urban vegetation. A field trial was conducted to assess the effect of this species on the cover and diversity of the native vegetation. The allelopathic potential of such species was examined. Sites comprising C. echinatus had a lower cover than some native species. Lower floristic diversity was observed at higher densities of this plant. The soil under this plant attained lower N, P, and K contents. This soil had no effect on the germination and growth of native species. It also comprised germinable seeds of some species which were absent from the standing vegetation. Exotic C. echinatus may exert negative effects on the native vegetation of the urban plant communities. A dense cover of this species may inhibit the germination of native species, leading to a reduction in their cover. Reduction in cover and diversity of native species may not be attributed to allelopathy. These results suggest that naturalized C. echinatus may be more competitive than the native ones, particularly at higher densities. Furthermore, it may represent a threat to the native plants in the urban vegetation.
Heteroblastic Inflorescence of ILamium amplexicaule/I L. in Egyptian Flora
Lamium amplexicaule L. (Family: Lamiaceae) is a cosmopolitan weed whose eradication is challenging. The phenoplasticity of this species is related to its heteroblastic inflorescence, which has not received adequate research worldwide in its morphological and genetic aspects. This inflorescence hosts two flower types, a cleistogamous (CL: closed flower) and a chasmogamous (CH: opened flower). This species subjected to detailed investigation is a model species to clarify: (1) the existence of the CL and CH flowers in relation to the time and individual plants. (2) the predominant flower morphs in Egypt. (3) the morphological and genetic variability between these morphs. Among the novel data retrieved from this work is the Presence of this species in three distinct morphs coexisting during winter. These morphs showed remarkable phenoplasticity, particularly in flower organs. Significant differences were observed between the three morphs in pollen fertility, nutlets productivity and sculpture, flowering time, and seed viability. These differences were extended to the genetic profile of these three morphs assessed by the inter simple sequence repeats (ISSRs) and start codon targeted (SCoT). This work highlights the urgent need to study the heteroblastic inflorescence of crop weeds to facilitate its eradication.
Herramienta anatómica como enfoque adicional para identificar especies de Efedra farmacéuticamente importantes (Ephedraceae) a nivel de identidad de género en Egipto,Anatomical Tool as Additional Approach for Identifying Pharmaceutically Important Ephedra Species (Ephedraceae) at Gender Identity Level in Egypt
The genus Ephedra Tourn. ex L. (Ephedraceae) is an important source with pharmacological and environmental potential. Conversely, Ephedra spp. still exhibit taxonomic complexity, especially for the specimens lacking reproductive cones. This complexity is attributed to its xeromorphic features, notably the reduced leaves and analogous assimilating branches, which make the species identification a real challenge. The current study provides a pioneering approach to distinguish fragments of Ephedra species at the gender level. This study was based on the stem anatomy and stem epidermal features using a light microscope for five species (E. alata Decne., E. aphylla Forssk., E. ciliata Fisch. & C.A.Mey., E. foeminea Forssk. and E. Ephedra pachyclada Boiss.) represented by ten genders collected from S. Sinai, Egypt. Anomocytic and brachyparacytic stomata, tanniniferous idioblasts, annual rings, a terete and furrowed outline, the number and width of tracheids, patches of cortical fibers, unicellular trichomes, druses, solitary crystals, and the activity of interfascicular cambium were among the distinguishing features that were found. Different statistical analyses were applied to explore the diversity at interspecific and intra-generic levels. This study revealed that the stem anatomy was not only an efficient tool for identifying the investigated five Ephedra species at the species level but also presented a differential key to distinguish between genders and species. In addition, our results indicated that the epidermal features played a critical role in differentiating the studied Ephedra species at the gender level. This study confirms the efficacy of stem anatomy as an identification approach for the Ephedra species at the gender level and recommends this approach to identify the fragmented Ephedra for taxonomical, pharmaceutical, and medical applications.
Alien Euphorbia hirta L. Induces Soil Sickness and Reduces Cover and Diversity of Native Species
The coexistence of alien species reduces the cover and diversity of native species. Euphorbia hirta L. has been documented as a naturalized alien weed. This study aimed to assess the potential interference of such species with the native urban vegetation. Thirty plots were conducted in sites affected by E . hirta and compared with an equal number of plots located outside these areas. Plant cover, species diversity, and various soil characteristics were measured at the study sites. A greenhouse experiment was conducted to demonstrate the effect of rhizosphere soil from alien species on specific native plants, namely Cynodon dactylon , Dactyloctenium aegyptium , and Melilotus indicus . Plots with E . hirta demonstrated low cover of annuals compared to perennial species. The presence of Euphorbia negatively affected species evenness, total cover, and biomass of native plants. Soils infested with E. hirta exhibited a significant reduction in both macro- and micronutrients. Principal component analysis (PCA) categorized the field criteria into two groups: plants with and without Euphorbia . Furthermore, the rhizosphere soil of Euphorbia significantly inhibited the growth of the native-tested species. The reduction observed in the measured vegetation criteria could be attributed to nutrient deficiency in soil induced by E . hirta . The allelopathic potential of this exotic species did not affect the native plants. These results suggest that E . hirta may be a stronger competitor than the native species. In addition, these species may pose a long-term threat to urban vegetation.