Indigenous medicinal plant of Ethiopia has been applied for the first time to investigate the synergistic influence of phytoconstituents in green copper nanoparticles (g-Cu NPs) towards the enhancement of antimicrobial properties of NPs. We report the green synthesis of Cu NPs using Hagenia abyssinica (Brace) JF. Gmel. leaf extract. The synthesized g-Cu NPs were characterized by UV-visible, UV-DRS, FT-IR, XRD, SEM, EDXA, TEM, HRTEM, and SAED techniques. The maximum absorbance, λmax, was found to be 403 nm for g-Cu NPs due to surface plasmon resonance. The energy gap, Eg of NPs, was found to be 2.19 eV. FTIR spectra confirmed the presence of polyphenols, tannins, and glycosides in the leaf extract of Hagenia abyssinica. The spectral band at 740 cm^-1 is a characteristic of interaction between Cu and biomolecules of the extract. The XRD analysis revealed that the g-Cu NPs appears to be more crystalline in nature. SEM and TEM micrographs showed a mix of spherical, hexagonal, triangular, cylindrical, and irregularly shaped Cu particles. The average particle size of NPs was found to be 34.76 nm by ImageJ analysis. EDX analysis confirmed the presence of copper in the g-Cu NPs. In addition, the SAED pattern of g-Cu NPs presented concentric circular patterns for 4 major planes of crystalline copper and its oxides. The experimental and calculated d-spacing values of one of the crystal planes (111) were found to be 0.2432 nm and 0.2444 nm, respectively. The d-spacing values of 0.2444 nm and 0.2040 nm correspond to d₁₁₁Cu₂O and d₁₁₁Cu lattice fringes, respectively. The antibacterial test conducted on E. coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis showed good zone of inhibitions 12.7, 12.7, 14.7, and 14.2 mm, respectively, proving potentiality of g-Cu NPs as a remedy for infectious diseases caused by tested pathogens.

Drought stress causes changes in the morphological, physiological, biochemical and molecular characteristics of plants. The response to drought in different plants may vary from avoidance, tolerance and escape to recovery from stress. This response is genetically programmed and regulated in a very complex yet synchronized manner. The crucial genetic regulations mediated by non-coding RNAs (ncRNAs) have emerged as game-changers in modulating the plant responses to drought and other abiotic stresses. The ncRNAs interact with their targets to form potentially subtle regulatory networks that control multiple genes to determine the overall response of plants. Many long and small drought-responsive ncRNAs have been identified and characterized in different plant varieties. The miRNA-based research is better documented, while lncRNA and transposon-derived RNAs are relatively new, and their cellular role is beginning to be understood. In this review, we have compiled the information on the categorization of non-coding RNAs based on their biogenesis and function. We also discuss the available literature on the role of long and small non-coding RNAs in mitigating drought stress in plants.

Plants have an inherent mechanism for perceiving drought stress and respond through a series of physiological, cellular and molecular changes for maintaining physiological water balance. It has been shown that nitrogen (N) and phosphate (P) can help to improve plant tolerance to water limitation by increasing the activities of the photosynthetic machinery and antioxidant enzymes. Maize is highly sensitive to drought stress, especially at the seedling stage. In this study, we used four maize genotypes (HKI-161, HKI-193-1, HQPM-1 and HQPM-7) and studied the effect of N and P application on response to drought stress and recovery at germination and seedling stage. We show that application of N and P had no effect on rate of germination but increased the seedling growth, chlorophyll content, malondialdehyde levels, proline, anthocyanin content, gas exchange parameters and antioxidant enzymes (APX, CAT and GR) during drought stress. The variation in the effect was visible across genotypes, but the observed changes indicate improved drought stress tolerance in the maize seedlings. During drought recovery, seedlings of HKI-161 and HKI-193-1 genotype that did not receive N and/or P treatment or that were pre-supplemented with only P showed rapid transition to flowering stages. Seedlings pretreated with N showed comparatively late transition to flowering. The HQPM-1 seedlings, which received N treatment moved to flowering stage while HQPM-7 seedlings showed only normal vegetative growth under all treatment conditions. Molecular analysis identified 2016 transcripts that are differentially expressed in the drought tolerant and susceptible genotypes. About 947 transcripts showed >3-fold change in expression and were expressed during stress tolerant genotype. Transcripts coding for proteins in P and N metabolism were identified within the drought regulated transcripts. The analysis showed that transcripts related to P metabolism were expressed during stress and recovery phases in the susceptible genotype while transcripts related to N metabolism were down regulated during drought stress and recovery stages in all the genotypes.

Mycotoxins are secondary metabolites secreted by many fungal species and found in many feeds and foodstuffs of especially in plants during their pre-and post-harvest, transportation, processing and storage and are detected in cereal crops. They are capable of causing disease and death in both humans and livestock and thereby induce great economic crisis. This review aims to examine the occurrence, prevention and control strategies of mycotoxins in Ethiopia; they are beneficial to the public and research institutes. Favorable environmental conditions such as temperature and prompting humidity facilitate fungal growth and mycotoxin development. Members of the fungal genera Aspergillus, Fusarium, and Penicillium cause frequent and problematic contamination of foods and feeds. Mycotoxin level of sample can be analyzed by sampling, preparation, extraction followed by a cleanup and detection performed by many instrumental and non-instrumental techniques; the molecular analysis is the best and promising approach. In Ethiopia, ochratoxins, fumonisins and aflatoxins frequently occur retarding crop production and livestock productivity; these in turn affect human health and income. To keep this effect dimmed, mycotoxin control and prevention mechanisms have a key role; prevention strategy weighs the overall effect. Moreover, biocontrol activities shall be strongly encouraged and focus has to be given to the aspect of mycotoxin. Key words: Mycotoxin, aflatoxin, ochratoxin, fumonisin.