The extreme conditions linked with abiotic stresses have greatly affected soil and plant health. The diverse biochemical activities occurring in the soil environment have been attributed to shaping the dynamics of plant–soil microbiomes by contributing to microbial lifestyles and enhancing microbial functional properties to boost plant tolerance to abiotic-induced stresses. Soil microbiomes play crucial roles in enhancing plant nutrition and abiotic stress management through diverse mechanisms. With the current insights into the use of engineered soil microbes as single or combined inoculants, their use has contributed to plant fitness and stability under different environmental stress conditions by activating plant defense mechanisms, enzyme production (lowering free radicals resulting in plant oxidative stress), protein regulation, and the production of growth factors. The detection of certain genes involved in the growth factors can underline microbial functions in mitigating plant stress. Hence, the projections for sustainable eco-friendly agriculture with the possible exploration of beneficial rhizosphere microbes to manage the effect of abiotic stress on plant nutrition remain critical points of discussion recently, with prospects for ensuring food security. Therefore, this review focuses on the impacts of soil microbiomes in abiotic stress mitigation for enhancing plant nutrition.

Petiole anatomy of 12 species of Asteraceae around Ile-Ife in South-Western Nigeria was described. Transverse section of the petiole (median) was cut at 20 µ using Reichert Sledge Microtome. The specimens were stained in 1% aqueous solution of Safranin O for 5 min, washed in three changes of water to remove excess stain and counterstained in 1% solution of Alcian blue for 5 min, and cleared in xylene. The section was mounted in DPX. The distinguishing characteristics of taxonomic value include, shapes of the petioles, variation in the number, arrangement and shapes of vascular bundles, types of trichomes. Key words: Asteraceae, petiole, anatomy, taxonomic, trichomes.

Trichomes are specialised epidermal structures on plant surfaces of plant aerial organs. They are integral to plant defence and adaptation. However, their elemental composition in Solanum species remains understudied. This research investigates the elemental composition of trichomes from five Solanum species, including representatives of the crops tomato and potato — Solanum berthaultii, Solanum galapagense, Solanum lycopersicum (tomato), Solanum pennellii, and Solanum tuberosum (potato) — using herbarium samples from the Royal Botanic Gardens, Kew. Samples were carbon coated and observed under the Field Emission Gun Scanning Electron Microscopy (FEG SEM). Energy Dispersive X-ray Spectroscopy (EDX/EDS) data were collected using an EDX detector. Results revealed significant variation in elemental content among the five Solanum species. The trichomes of S. berthaultii showed high levels of potassium (K), especially at the tips, suggesting a role in osmoregulation and defence. S. galapagense exhibited notable chlorine (Cl) and calcium (Ca) presence, possibly for ionic balance and pest deterrence. S. lycopersicum and S. pennellii had higher silicon (Si) concentrations in the mid-sections and tips of the trichomes, enhancing structural integrity and herbivory resistance. S. tuberosum displayed significant variability in calcium (Ca), particularly at the base, in which could be of importance for maintaining cellular structure and for rapid damage response. This study provides insights into the elemental composition of the trichomes of Solanum species, contributing to our understanding of their ecological and physiological roles. Our findings underscore the importance of elemental composition in studies of plant adaptation and evolution, offering a foundation for future research in plant defence mechanisms and environmental interactions.

Foliar epidermal studies were carried out on accessions of Andropogon gayanus-Andropogon tectorum complex collected in Southwestern Nigeria with a view to providing additional characters of the two species of Andropogon to enhance the understanding of the taxonomic relationship between the two species. The epidermal preparation of the adaxial and abaxial surfaces of the leaf blade was made from the median part of well-matured leaf samples by the scrapping method. The analysis of both qualitative and quantitative characters revealed that study revealed that the costal zones of both adaxial and abaxial surfaces of all accessions studied showed similar features with little or no variation in their expression; epidermal cells are mostly rectangular with wavy walls, and the stomata encountered are paracytic. There was a unique occurrence of cluster of cells at the base of the macro hairs present in A. gayanus which is a diagnostic feature for its accessions collected. Kiwani, an unidentified polyploid accession, has the highest number of bands, the stomata are bigger, which is consistent with gigas effect occasioned by its polyploidy status. Glandular trichomes were present in both diploid and tetraploid of A. tectorum, a diagnostic feature for the species.

Morphological studies were carried out on collections of Andropogon gayanus-Andropogon tectorum complex from Southwestern Nigeria. This is with the view to providing full characterization of the accession of the two species of Andropogon and elucidating their population dynamics. Morphological data from selected accessions of A. gayanus and A. tectorum from different parts of Southwestern Nigeria were collected and characterized using an adaptation of the Descriptors for Wild and Cultivated Rice (Oryza spp ) , Biodiversity International. Preliminary morphological description of the accessions were carried out at the point of collection. Garden populations were raised from the vegetative parts of some accessions and maintained in Botanical Garden of the Obafemi Awolowo University, Ile-Ife. The data obtained were subjected to inferential tests and Duncan’s multiple range test. The results revealed a distinct distribution pattern of the two species of Andropogon in the area of study which suggests a south-ward migration of Andropogon gayanus , that is from the northern vegetational zones of Nigeria to the southern ecological zones. The migration of A. gayanus around Igbeti with occasional occurrence of A. tectorum along the roadsides without any distinct phenotypic hybrid, and Budo-Ode in Oyo State is established as the southern limit of the spread of A. gayanus . This migration of A. gayanus to the South is not an invasion but a slow process. There was no A. gayanus encountered in Osun, Ondo, Ekiti and Ogun States. Andropogon gayanus and Andropogon tectorum do not only emerge from the rootstocks rapidly but can also produce independent propagules by rooting at some nodes. The plants can spread by means of these propagules even if it does not produce sexual or apomictic seeds. This potential for vegetative propagation in addition to the perennial habit confer considerable advantage for colonization by the Andropogon gayanus-Andropogon tectorum complex.