The anatomy as a tool for the identification of the bark of Pterocarpus angolensis and Terminalia sericea

Pterocarpus angolensis and Terminalia sericea are two African species with medicinal potential. Despite the importance of their bark as a powerful astringent to treat various diseases it is poor described. In order to provide referential information for correct identification and standardization of the plant material, bark samples from each two species were collected and analyzed under light and electron microscopy. Some important anatomical features to identification were: the sclerenchyma tissue mostly in form of fibre-sclereids and the large secretory cells arranged in conspicuous rows or tangential bands in the conducting phloem in P. angolensis; the crystalliferous cells arranged in very regular tangential rows (druses) and the occurrence of large crystal cells near or including the tangential fibre bundles in T. sericea bark.The results obtained show that the anatomy of the bark can be used as an important subsidy in identification and standardization of the studied species contributing the scientific knowledge for more effective forms of scrutiny in preventing commercial adulteration of species

Tropical Plant Responses to Climate Change

Editorialinfo:eu-repo/semantics/publishedVersio

Biodiversity Studies in Key Species from the African Mopane and Miombo Woodlands

The Southern African Miombo-Mopane woodlands are globally considered as ecosystems with irreplaceable species endemism, being the most important type of vegetation in the region. Among the approximately 8500 plant species, legume trees play a crucial role in biodiversity dynamics, being also key socioeconomic and environmental players. From the ecological point of view, they contribute significantly to ecosystem’s stability as well as to water, carbon, and energy balance. Additionally, legume species represent an immensurable source of timber and nontimber products. Research in Miombo-Mopane biodiversity has been mainly focused on the analysis of ecosystem drivers by means of ecological parameters and models, lacking interdisciplinary with relevant cross-cutting tools, such as the application of molecular markers to assess genetic diversity within the region. In this chapter, the applications and biodiversity dynamics of typical legume species from Miombo (Brachystegia spp., Julbernardia globiflora, and Pterocarpus angolensis) and Mopane (Colophospermum mopane) are reviewed. Gaps and challenges are also brought forward in the context of the lack of genetic diversity assessments and the need of an effective and coordinated network of interdisciplinary research

The Potential of Tree and Shrub Legumes in Agroforestry Systems

Climate variability and changes are utmost important primary drivers of biological processes. They are intimately associated with a wide array of abiotic stresses, highlighting the vulnerability of ecosystems and endangering biodiversity. Nitrogen‐fixing trees and shrubs (NFTSs) constitute a unique group of plants for their wide range of applications at the environmental, social and economic levels. In this chapter, we review and analyse the potential of this group of legumes in agroforestry towards sustainable agriculture in Africa. In the first part, the intertwined pillar of sustainable agriculture is brought forward under the context of growing population and climate changes. The second part addresses general aspects of legumes, including botany and the symbiosis with rhizobia. The third part includes the application of NFTS as N‐fertilizers in agroforestry, highlighting the importance of an accurate choice of the crop(s)/NFTS combination(s) and cropping type (intercropping, multistrata or fallows). The implementation of agroforestry systems with NFTS should be supported by fundamental research strategies such as stable isotopes and systems biology and preceded by experimental assays, in order to identify the factors promoting N‐losses and to design appropriate management strategies that synchronize legume‐N availability with the crop demand

Diversity of cowpea (Vigna unguiculata (L.) Walp) landraces in Mozambique: new opportunities for crop improvement and future breeding programs

Cowpea (Vigna unguiculata) is a neglected crop native to Africa, with an outstanding potential to contribute to the major challenges in food and nutrition security, as well as in agricultural sustainability. Two major issues regarding cowpea research have been highlighted in recent years—the establishment of core collections and the characterization of landraces—as crucial to the implementation of environmentally resilient and nutrition-sensitive production systems. In this work, we have collected, mapped, and characterized the morphological attributes of 61 cowpea genotypes, from 10 landraces spanning across six agro-ecological zones and three provinces in Mozambique. Our results reveal that local landraces retain a high level of morphological diversity without a specific geographical pattern, suggesting the existence of gene flow. Nevertheless, accessions from one landrace, i.e., Maringué, seem to be the most promising in terms of yield and nutrition-related parameters, and could therefore be integrated into the ongoing conservation and breeding efforts in the region towards the production of elite varieties of cowpeainfo:eu-repo/semantics/publishedVersio

A Transcriptomic Approach to Understanding the Combined Impacts of Supra-Optimal Temperatures and CO2 Revealed Different Responses in the Polyploid Coffea arabica and Its Diploid Progenitor C. canephora

Understanding the effect of extreme temperatures and elevated air (CO2) is crucial for mitigating the impacts of the coffee industry. In this work, leaf transcriptomic changes were evaluated in the diploid C. canephora and its polyploid C. arabica, grown at 25 C and at two supra-optimal temperatures (37 C, 42 C), under ambient (aCO2) or elevated air CO2 (eCO2). Both species expressed fewer genes as temperature rose, although a high number of differentially expressed genes (DEGs) were observed, especially at 42 C. An enrichment analysis revealed that the two species reacted differently to the high temperatures but with an overall up-regulation of the photosynthetic machinery until 37 C. Although eCO2 helped to release stress, 42 C had a severe impact on both species. A total of 667 photosynthetic and biochemical related-DEGs were altered with high temperatures and eCO2, which may be used as key probe genes in future studies. This was mostly felt in C. arabica, where genes related to ribulose-bisphosphate carboxylase (RuBisCO) activity, chlorophyll a-b binding, and the reaction centres of photosystems I and II were down-regulated, especially under 42 C, regardless of CO2. Transcriptomic changes showed that both species were strongly affected by the highest temperature, although they can endure higher temperatures (37 C) than previously assumed.info:eu-repo/semantics/publishedVersio

Elaboration of films from plant residues: a more sustainable alternative to the environment

info:eu-repo/semantics/publishedVersio

Elaboration of films from plant residues: a more sustainable alternative to the environment

info:eu-repo/semantics/publishedVersio

Salt Stress Tolerance in Casuarina glauca: Insights from the Branchlets Transcriptome

Climate change and the accelerated rate of population growth are imposing a progressive degradation of natural ecosystems worldwide. In this context, the use of pioneer trees represents a powerful approach to reverse the situation. Among others, N2-fixing actinorhizal trees constitute important elements of plant communities and have been successfully used in land reclamation at a global scale. In this study, we have analyzed the transcriptome of the photosynthetic organs of Casuarina glauca (branchlets) to unravel the molecular mechanisms underlying salt stress tolerance. For that, C. glauca plants supplied either with chemical nitrogen (KNO3 +) or nodulated by Frankia (NOD+) were exposed to a gradient of salt concentrations (200, 400, and 600 mM NaCl) and RNA-Seq was performed. An average of ca. 25 million clean reads was obtained for each group of plants, corresponding to 86,202 unigenes. The patterns of differentially expressed genes (DEGs) clearly separate two groups: (i) control- and 200 mM NaCl-treated plants, and (ii) 400 and 600 mM NaCltreated plants. Additionally, although the number of total transcripts was relatively high in both plant groups, the percentage of significant DEGs was very low, ranging from 6 (200 mM NaCl/NOD+) to 314 (600 mM NaCl/KNO3 +), mostly involving down-regulation. The vast majority of up-regulated genes was related to regulatory processes, reinforcing the hypothesis that some ecotypes of C. glauca have a strong stress-responsive system with an extensive set of constitutive defense mechanisms, complemented by a tight mechanism of transcriptional and post-transcriptional regulation. The results suggest that the robustness of the stress response system in C. glauca is regulated by a limited number of genes that tightly regulate detoxification and protein/enzyme stability, highlighting the complexity of the molecular interactions leading to salinity tolerance in this speciesinfo:eu-repo/semantics/publishedVersio