This study evaluated genetic variability and heritability in vegetative and floral characters among two minor legumes (Sphenotylis stenocarpa Ex. A. Rich. Harms and [Cajanus cajan (L.) Millsp.] of five accessions each. Six (6) floral and ten (10) vegetative characters were pooled for analysis on one hundred (100) plants of the two minor legumes. Appropriate statistical analyses were employed for comparative evaluation. Significant differences (P = 0.05) were observed in all the traits except rachis length. Principal Component Analysis (PCA) revealed significant contributions of traits in lengths of calyx lobe, stipule, rachis and petiole; also in numbers of flowers per peduncle and of main branches to the expressed variability. The cluster analysis segregated the accessions into two major cluster groups. The broad sense heritability of traits was high (>95 %). The study is important in selection of valuable traits for conservation, management of genetic resources and hybridization programs of the two species.

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This study emphasizes the production of eco-friendly silver nanoparticles from a medicinal plant extract of Morinda lucida (M. lucida) and investigated its antioxidant and antimicrobial activity. Phytochemical screening of M. lucida (ML) leave extract was carried out and observed to contain some fundamental phyto-reducing agents such as reducing sugar, proteins, and alkaloids. The green synthesized AgNPs (ML-AgNPs) were characterized by UV–vis spectroscopy, Fourier transform infrared spectroscopy (FTIR), transmission emission microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), and Energy dispersive X-ray analysis (EDX). Thermo gravimetric analysis (TGA) was performed on the synthesized ML-capped AgNPs to determine the thermal stability and the formation of the green synthesized AgNPs. The formation of AgNPs was confirmed by the UV–vis absorption spectra, which showed an absorption band at 420 nm. The morphology of ML extract-mediated AgNPs was mostly spherical and rough-edged crystallite nanostructures, with an average particle size of 11 nm. The FTIR analyses revealed distinctive functional groups which were directly involved in the synthesis and stability of AgNPs. The crystallite size was 8.79 nm, with four intense peaks at 2 θ angles of 38°, 44°, 64°, and 77°. At an energy level of 3.4 keV, a significant signal was observed indicating the production of thermally stable and pure crystallite AgNPs. The antioxidant property of green synthesized ML-AgNPs was determined to be 40% higher than that of crude M. lucida leaf extract. The ability of green synthesized ML-AgNPs to scavenge free radicals also increased in the order of OH − < NO < H 2 O 2 . The ML-AgNPs have strong activities with a maximum against P. vulgaris and a minimum with E. faecalis.

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Wheat (Triticum aestivum) is an important grains plant that can sustain food security and holds high nutritional values to the benefit of mankind. Activities of salinity in arid and semi-arid region have drastically reduced the production of wheat grains. Selenium (Se) is a micronutrient required by plants in small concentration to aid their growth. This study was aimed at identifying impact of Se on salinity-stressed wheat plants. Wheat seeds were soaked for eight hours in 0, 50, 100 and 150 mg/L Selenite concentrations and five sterilize-treated seeds were sown in 5 kg quantity of soil. This was subjected to 0, 100 and 200 mM of Sodium chloride (NaCl) concentration, respectively. The study revealed that Se increased production/expression of superoxide dismutase and catalase enzymes under salinity stress, thus growth of wheat plants was improved. Although the effects of Se on the wheat plants were concentration-based, nevertheless low lipid peroxidation and plant growth at 150 mg/L of Se were observed. Toxicity of Se to wheat plant could occur when there is no salinity stress. Therefore, farmers are encouraged to prime wheat seeds with 150 mg/L Se when cultivating saline soils.

Water stress is an enormous problem facing food production, especially in arid and semi-arid regions. Production of free radicals during water stress has led to oxidative stress, which eventually causes death of cells in plants. Therefore, it is important to tackle this issue knowing that rice is one of the most important cereal crops largely cultivated and consumed by humans and animals. The studies aimed at the effect of selenite on physiological and biochemical activities of water-stressed upland rice. Three Upland rice cultivars namely Nerica U4, Nerica U7 and Vandana were collected in Africa Rice Centre, Ibadan. The seeds were sterilized and soaked for 10 hours in different concentrations of Selenite (Se) (0 mg/l, 50 mg/l and 100 mg/l). Primed seed were planted into sterilized-sieved top soils. Plants were subjected to 0 (irrigated) and 8 days (non-irrigated) water stress. Selenite 50 mg/l improved plant height, number of leaves, total carotene, chlorophyll contents, biomass, grain number of upland rice during water stress. Selenite increased activities of APX as water stress progressively increased consequently, low MDA content was observed in cultivar Vandana. Furthermore, selenite significantly improved total carotene, chlorophyll contents, anthocyanin, and dry shoot weight in cultivar Nerica U7 during water stress. Selenite significantly stabilized activities of anthocyanin and CAT in cultivar Nerica U4 during water stress. Hence high grain yield was recorded in Nerica U4 and U7 in selenite primed upland rice during water stress. Selenite reduced lipid peroxidation in upland rice at 100mg/l. Therefore, it can be concluded that response of rice to selenite during water stress is based on tolerance capacity of the cultivars and also, selenite 50mg/l can help to improve growth and yield of upland rice in drought-prone area.

Cell and sub‐cellular anatomical adjustments are adaptations utilized by plants to tolerate abiotic stress. Both melatonin and Morinda lucida‐silver nanoparticles (ML‐AgNPs) are recognized as bio‐stimulants. The study examined the morphological changes and adaptive characteristics of these bio‐stimulants under water‐stress Eugenia uniflora. Twenty‐four hours was spent priming the seeds with melatonin (0.06 mg/L), ML‐AgNPs (0.06 mg/L), and a mixture (1:1) of the two. The seeds were sown and subjected to water stress for 7 days. The leaves, stems, and roots of water‐stressed E. uniflora were sectioned, dried, and examined using a microscope. Drought stress led to the production of non‐glandular trichomes on the abaxial and the transformation of paracytic stomata into diacytic stomata. During water stress, melatonin enlarges intercellular gaps and stomata, increases sponge and palisade parenchyma, and thickens epidermis (stem and root) and fibers. The ML‐AgNPs diminished the size of mesophyll, intercellular gaps, stomata, and stem fiber. The ML‐AgNPs increased the size of bulliform cells and activated the mechanical resistance features of sclerophyllous leaves (thick‐celled epidermis and sclerieds) and ray parenchyma (root and stem). Equally, Melatonin and ML‐AgNPs increased stem and root anatomical characteristics (xylem, bark, pith, cortex, epidermis, and vascular bundles). Stomata of E. uniflora are susceptible to alterations and undergo cell division into two new stomata (stomatogensis) in response to varying conditions (melatonin and ML‐AgNPs). Melatonin adopted a strategy for maintaining a high plant water status, possibly by osmoregulation, whereas E. uniflora primed with ML‐AgNPs survived by minimizing transpirational water loss through morphological changes.

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