An overview of actinorhizal plants in Africa

2011 ◽  
Vol 38 (9) ◽  
pp. 653 ◽  
Author(s):  
Maher Gtari ◽  
Jeffrey O. Dawson
Keyword(s):  
Native Species ◽  
Root Nodules ◽  
Alnus Glutinosa ◽  
Wildlife Habitat ◽  
Actinorhizal Plants ◽  
Current Status ◽  
Arid Zones ◽  
African Countries ◽  
Climatic Regions ◽  
Actinorhizal Species

A compilation and synthesis of information derived from plant databases and other sources on the occurrence, diversity and geographic distribution of actinorhizal plants in Africa is presented in this review. Actinorhizal plants are a specific group of non-leguminous, woody dicots having symbiotic, nitrogen-fixing root nodules that are induced on roots of actinorhizal plant species by soil actinomycetes of the genus Frankia. There is a lack of basic information on actinorhizal plants in Africa compared with other major land masses in the world. Results indicate that most, if not all, African countries and climatic regions have native or introduced actinorhizal species. A synthesis of available information indicates that there are six families, nine genera and 38 reported species of actinorhizal plants in Africa. Of these, 21 species are native and 17 are exotic. The families and corresponding number of species in each genus are: Betulaceae (native Alnus glutinosa (1), exotic Alnus (2)); Casuarinaceae (exotic Casuarina (5), exotic Allocasuarina (3), exotic Gymnostoma deplancheana (1)); Coriariaceae (native Coriaria myrtifolia (1)); Myricaceae (native Morella (19), exotic Morella cerifera (1)); Rhamnaceae (exotic Ceanothus caeruleus (1), exotic Colletia paradoxa (1)); and Elaeagnaceae (exotic Eleaegnus angustifolia (1)). Four reports of native, actinorhizal Ceanothus species in Africa found in the database were determined to be false, instead, being non-actinorhizal species. Widespread plantings of exotic Casuarinaceae have been introduced into tropical and arid zones of Africa as multipurpose trees, especially in arid regions where native species do not occur. There is a diverse assemblage of native species of Morella in Africa, mostly shrubs or small trees, which provide medicine, other useful chemicals and wildlife habitat. Many native Morella species are isolated in montane islands, apparently leading to greater speciation than in Eurasia from where the genus migrated into Africa. The current status and knowledge of African actinorhizal plants indicates a need to focus research on their biogeography, biology, ecology, genetics and use.

scholarly journals Distinct Patterns of Symbiosis-Related Gene Expression in Actinorhizal Nodules from Different Plant Families

2003 ◽  
Vol 16 (9) ◽  
pp. 796-807 ◽  
Author(s):  
Katharina Pawlowski ◽  
Susan Swensen ◽  
Changhui Guan ◽  
Az-Eddine Hadri ◽  
Alison M. Berry ◽  
...  
Keyword(s):  
Gene Expression ◽  
Root Nodules ◽  
Phylogenetic Analyses ◽  
Expression Patterns ◽  
Alnus Glutinosa ◽  
Actinorhizal Plants ◽  
Gene Expression Patterns ◽  
Homologous Genes ◽  
Molecular Phylogenetic ◽  
Plant Families

Phylogenetic analyses suggest that, among the members of the Eurosid I clade, nitrogen-fixing root nodule symbioses developed multiple times independently, four times with rhizobia and four times with the genus Frankia. In order to understand the degree of similarity between symbiotic systems of different phylogenetic subgroups, gene expression patterns were analyzed in root nodules of Datisca glomerata and compared with those in nodules of another actinorhizal plant, Alnus glutinosa, and with the expression patterns of homologous genes in legumes. In parallel, the phylogeny of actinorhizal plants was examined more closely. The results suggest that, although relationships between major groups are difficult to resolve using molecular phylogenetic analysis, the comparison of gene expression patterns can be used to inform evolutionary relationships. In this case, stronger similarities were found between legumes and intracellularly infected actinorhizal plants (Alnus) than between actinorhizal plants of two different phylogenetic subgroups (Alnus/Datisca).

Institutional Repositories in Swaziland: An Exploratory Study

Mousaion ◽  
2019 ◽  
Vol 36 (2) ◽  
Author(s):  
Ncamsile Nombulelo Dlamini ◽  
Maritha Snyman
Keyword(s):  
Open Access ◽  
Exploratory Study ◽  
Management Strategies ◽  
Current Status ◽  
Academic Institutions ◽  
African Countries ◽  
Institutional Repositories ◽  
Limited Knowledge ◽  
Advocacy Strategies ◽  
Awareness Level

The purpose of this paper is to assess the current status of institutional repositories (IRs) in Swaziland’s academic institutions. The factors under discussion are the number of IRs in Swaziland, their usage, the level of awareness of these IRs, and the challenges that prevent the implementation of IRs in Swaziland’s academic institutions. A webometric approach, interviews and semi-structured questionnaires completed by IR managers or librarians working for the Swaziland’s academic institutions were used to collect data for this study. Responses were received from 11 respondents. The findings indicated that there is one IR in Swaziland that is accessible to the institution’s community via the intranet. This IR was, at the time when this study took place, not registered in any of the international registries of repositories, such as the Registry of Open Access Repositories (ROAR) and the Directory of Open Access Repositories (OpenDOAR). Currently, this IR faces problems of insufficient content, a low level of IR awareness, limited knowledge of effective and appropriate IR advocacy strategies and limited knowledge of effective IR implementation and management strategies. Based on the findings and information gained from a literature review of IRs, the paper recommends strategies to academic institutions in Swaziland that may enable them to increase their number of IRs, the awareness level of IRs and consequently the use of IRs. The findings and recommendations may also benefit other African countries in similar situations.  

ASSIMILATION OF NITROGEN IN ROOT NODULES OF ALDER (ALNUS GLUTINOSA)

1981 ◽  
Vol 89 (2) ◽  
pp. 321-326 ◽  
Author(s):  
JAN BLOM ◽  
WIM ROELOFSEN ◽  
ANTOON D. L. AKKERMANS
Keyword(s):  
Root Nodules ◽  
Alnus Glutinosa

Institutional repositories in Africa: Regaining direction

2021 ◽  
pp. 026666692110154
Author(s):  
Usman Ahmed Adam ◽  
Kiran Kaur
Keyword(s):  
Open Access ◽  
Research Output ◽  
Current Status ◽  
African Countries ◽  
Institutional Repositories ◽  
Widespread Implementation ◽  
Typical Performance ◽  
The Status ◽  
Global Access ◽  
And Cluster Analysis

Institutional repositories are powerful tools to facilitate global access to intellectual output by members of the institution, particularly in assisting them to preserve and maximize access to their research output globally. This exploratory study of the status of institutional repositories implementation in African countries using the global Directory of Open Access Repositories (OpenDOAR) and Transparent Ranking: All Repositories by Google Scholar, reports on the operational status and the performance of repositories. Factor analysis and cluster analysis are used to analyze the operational level of institutional repositories in African countries. The analysis showed that the typical performance of institutional repositories remains below average. The possibility of global open access to research results through institutional repositories in South Africa, Kenya, Nigeria, Algeria, Sudan, and Egypt appeared to be relatively more feasible than other African countries. This study concludes that many organizations, institutions, and societies spend great efforts in support of open access implementation in Africa, however, the widespread implementation of institutional repositories is still very slow paced, and the performance of the implemented repositories was below expectation. Suggestions for regaining the intended direction of African institutional repositories are given based on the current status.

Water and sanitation in Africa: current status, trends, challenges and opportunities

2017 ◽  
Author(s):  
George Kararach ◽  
Tito Yepes
Keyword(s):  
Economic Growth ◽  
Rural Poverty ◽  
Water Security ◽  
River Basins ◽  
Current Status ◽  
Institution Building ◽  
Infrastructure Development ◽  
African Countries ◽  
Hydrological Variability ◽  
Challenges And Opportunities

Africa faces difficult water/sanitation legacies in the form of high hydrological variability and a multiplicity of transboundary river basins alongside poor sanitation. These challenges impeded the continent’s economic growth. Balanced investments in water resource and sanitation infrastructure and institutions are needed to increase productive uses of water, to mitigate the effect of recurrent floods and droughts, and to achieve basic water security as a platform for Africa’s economic growth. Priority should be given to investments that (a) focus on growth, (b) reduce rural poverty, (c) build climate resilience and adaptation, and (d) foster cooperation in international river basins. Because most African countries have low stocks of hydraulic infrastructure, emphasizing investments in infrastructure is appropriate for them. However, institution building and reform, improvements in water/sanitation management and operations, and strengthening of water information systems must complement growth in infrastructure. Development of institutions should be advanced in parallel with infrastructure investment.

scholarly journals Alone Yet Not Alone: Frankia Lives Under the Same Roof With Other Bacteria in Actinorhizal Nodules

2021 ◽  
Vol 12 ◽  
Author(s):  
Faten Ghodhbane-Gtari ◽  
Timothy D’Angelo ◽  
Abdellatif Gueddou ◽  
Sabrine Ghazouani ◽  
Maher Gtari ◽  
...  
Keyword(s):  
16S Rrna ◽  
Plant Growth ◽  
16S Rrna Gene ◽  
Root Nodules ◽  
Actinorhizal Plants ◽  
Rrna Gene ◽  
Plant Growth Promoting Bacteria ◽  
Metagenomic Sequencing ◽  
Plant Growth Promoting ◽  
Growth Promoting

Actinorhizal plants host mutualistic symbionts of the nitrogen-fixing actinobacterial genus Frankia within nodule structures formed on their roots. Several plant-growth-promoting bacteria have also been isolated from actinorhizal root nodules, but little is known about them. We were interested investigating the in planta microbial community composition of actinorhizal root nodules using culture-independent techniques. To address this knowledge gap, 16S rRNA gene amplicon and shotgun metagenomic sequencing was performed on DNA from the nodules of Casuarina glauca. DNA was extracted from C. glauca nodules collected in three different sampling sites in Tunisia, along a gradient of aridity ranging from humid to arid. Sequencing libraries were prepared using Illumina NextEra technology and the Illumina HiSeq 2500 platform. Genome bins extracted from the metagenome were taxonomically and functionally profiled. Community structure based off preliminary 16S rRNA gene amplicon data was analyzed via the QIIME pipeline. Reconstructed genomes were comprised of members of Frankia, Micromonospora, Bacillus, Paenibacillus, Phyllobacterium, and Afipia. Frankia dominated the nodule community at the humid sampling site, while the absolute and relative prevalence of Frankia decreased at the semi-arid and arid sampling locations. Actinorhizal plants harbor similar non-Frankia plant-growth-promoting-bacteria as legumes and other plants. The data suggests that the prevalence of Frankia in the nodule community is influenced by environmental factors, with being less abundant under more arid environments.

scholarly journals OVERVIEW OF RESEARCH OF MUSHROOMS IN SRI LANKA

2017 ◽  
Vol 40 (4) ◽  
pp. 399-403
Author(s):  
Samantha C. Karunarathna ◽  
Peter E. Mortimer ◽  
Jianchu Xu ◽  
Kevin D. Hyde
Keyword(s):  
Sri Lanka ◽  
Future Development ◽  
Native Species ◽  
Ornamental Plants ◽  
Current Status ◽  
Sri Lankan ◽  
Mycological Research ◽  
The Future ◽  
Available Information

According to recent estimates the mycota of Sri Lanka is highly diverse, yet it has been relatively little studied and remains poorly understood. Sri Lanka may contain up to 25,000 species of fungi, of which only a little more than 2000 are presently known, and this estimate does not take into account the large number of exotics introduced along with food, plantation, and ornamental plants. Mycological research in Sri Lanka has been limited to certain parts of the country, and the available information is widely dispersed, difficult to access, and plagued by synonymy. Commercially cultivable mushrooms were first introduced to Sri Lanka in 1985, and today both endemic and non-native species are cultivated. This paper addresses the current status of Sri Lankan mushroom research, and suggests measures which are needed to support the future development of Sri Lankan mycology.

scholarly journals Salinity-induced changes in the morphology, physiology, and anatomy of seeds and seedlings of smooth narra (Pterocarpus indicus Willd. f. indicus)

2020 ◽  
Vol 21 (11) ◽  
Author(s):  
MARJORIE M. MANIPOL ◽  
CRUSTY E. TINIO ◽  
LERMA SJ. MALDIA ◽  
Marilyn S. Combalicer
Keyword(s):  
Native Species ◽  
Root Nodules ◽  
Cell Number ◽  
The Philippines ◽  
Soil Conditions ◽  
Root Shoot Ratio ◽  
Number Of Leaves ◽  
Collar Diameter ◽  
Induced Changes ◽  
Harsh Conditions

Abstract. Manipol MM, Tinio CE, Maldia LSJ, Combalicer MS. 2020. Salinity-induced changes in the morphology, physiology, and anatomy of seeds and seedlings of smooth narra (Pterocarpus indicus Willd. f. indicus). Biodiversitas 21: 5146-5154. Pterocarpus indicus Willd. forma indicus is a commonly planted species for reforestation in the Philippines regardless of the area’s condition. Since the species could survive in areas even with harsh conditions, it was hypothesized that the species may also thrive in areas having substantial amount of salt, especially during its early growth. This study assessed the morphological, physiological, and anatomical responses of seeds and seedlings of P. indicus Willd. f. indicus (Fabaceae), a native species in the Philippines to varying salt (NaCl) concentrations (0-300 mM). Based on the results, P. indicus f. indicus grew significantly in terms of height, number of leaves, leaf area, root collar diameter (RCD), root nodules, and root-shoot ratio in the control and at 100 mM NaCl. On the other hand, the growth of the species was suppressed at 300 mM NaCl. The physiological characteristics (germination, survival, and photosynthetic rates) were also high in the control compared to the NaCl treatments. As for the seed anatomical characteristics, the radicle cells remained undamaged, with high cell number and longer cells in the control, but showed damaged and reduced cell number and length at 300 mM NaCl. This indicates that P. indicus f. indicus can only tolerate moderate saline soil conditions. Hence, this result needs to be considered in reforestation efforts of the country using this species.

scholarly journals Lassa Fever: Viral Replication, Disease Pathogenesis, and Host Immune Modulations

Pathogens ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 437
Author(s):  
Hinh Ly
Keyword(s):  
Lassa Fever ◽  
West African ◽  
Host Factors ◽  
Current Status ◽  
Special Issue ◽  
African Countries ◽  
Disease Pathogenesis ◽  
Virus Life Cycle ◽  
Key Issues ◽  
Made In

Despite major discoveries made in the last few decades about Lassa fever, there are still many unresolved key issues that hamper the development of effective vaccines and therapies against this deadly disease that is endemic in several West African countries. Some of these issues include the lack of a detailed understanding of the viral and participating host factors in completing the virus life cycle, in mediating disease pathogenesis or protection from disease, and in activating or suppressing host innate and cellular immunity against virus infection, as well as of the animal models required for testing vaccines and therapeutics. This Special Issue is devoted to understanding some of these important issues and to exploring the current status of the research and development in combating Lassa fever.

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