In this study, the role of selenium nanoparticles (SeNPs, 10 mg·L⁻¹) has been investigated in modulating the negative effects of drought and heat stresses on eight bread wheat (Triticum aestivum L.) genotype seedlings. Those genotypes included Giza-168, Giza-171, Misr-1, Misr-3, Shandweel-1, Sids-1, Sids-12, and Sids-14. The study included six treatments as follows: regular irrigation with 100% Field Capacity (FC) at a temperature of 23 ± 3 °C (T1), drought stress with 60% FC (T2), heat stress of 38 °C for 5 h·day⁻¹ (T3), foliar spray of 10 mg·L⁻¹ of SeNPs only (T4), a combination of drought stress with foliar spray of 10 mg·L⁻¹ of SeNPs (T5), and heat stress with foliar spray of 10 mg·L⁻¹ of SeNPs (T6). The experiment continued for 31 days. Foliar application of SeNPs improved the plant growth, morpho-physiological and biochemical responses, and expression of stress-responsive genes in wheat (T. aestivum L.) seedlings. Overall, morpho-physiological traits such as plant height (PH), shoot fresh weight (SFW), shoot dry weight (SDW), root fresh weight (RFW), and root dry weight (RDW) of wheat genotypes grown under different conditions ranged from 25.37–51.51 cm, 3.29–5.15 g, 0.50–1.97 g, 0.72–4.21 g, and 0.11–1.23 g, respectively. From the morpho-physiological perspective, drought stress had a greater detrimental impact on wheat plants than heat stress, whereas heat stress significantly impacted the expression of stress-responsive genes. Stress responses to drought and heat varied between wheat genotypes, suggesting that different genotypes are more resilient to stress. Exogenous spraying of 10 mg·L⁻¹ of SeNPs improved the photosynthetic pigments, photosynthetic rate, gas exchange, and transpiration rate of wheat plants and enhanced drought and heat tolerance by increasing the activity of antioxidant enzymes including catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) and the expression level of stress-responsive genes. Our results showed that spraying wheat seedlings with 10 mg·L⁻¹ of SeNPs enhanced SOD activity for all genotypes as compared to the control, with the Sids-12 genotype having the highest value (196.43 U·mg⁻¹ FW·min⁻¹) and the Giza-168 genotype having the lowest (152.30 U·mg⁻¹ FW·min⁻¹). The expression of PIP1, LEA-1, HSP70, and HSP90 stress-responsive genes was more significant in tolerant genotypes (Giza-171 and Giza-168) than in sensitive ones (Misr-1 and Misr-3) in response to drought and heat stresses. Under stress conditions, the shoot and root fresh weights, photosynthetic pigment content, stomatal conductance (SC), and transpiration rate (TR) were positively correlated with plant height (PH), while root and shoot dry weights, malondialdehyde (MDA), proline, hydrogen peroxide (H₂O₂), and APX were negatively correlated. Multivariate analysis and biplot results revealed that genotypes Giza-168, Giza-171, Sids-12, and Sids-14 performed well in both stress situations and were classified as stress-tolerant genotypes. These best genotypes may be employed in future breeding projects as tools to face climate change. This study concluded that various physio-biochemicals and gene expression attributes under drought and heat stress could be modulated by foliar application of SeNPs in wheat genotypes, potentially alleviating the adverse effects of drought and heat stress.

The green synthesis of zinc oxide nanoparticles (ZnO-NPs) mediated fruit peel extract is gaining importance due to its cost-effectiveness and ecofriendly nature. Herein, ZnO-NPs were synthesized using pomegranate peel extract as a reducing and stabilizing agent. The synthesized ZnO-NPs were characterized using SEM, TEM-SAID, FT-IR, XRD, and particle size analysis. According to the findings, the ZnO-NPs were agglomerated into spherical and hexagonal shapes with an average diameter of 20 to 40 nm and crystallinity formed. The antimicrobial activity of ZnO-NPs against pathogenic microbes was significant in multiple applications, with 62.5 and 31.25 μg/ml of MIC for both Gram-positive and Gram-negative bacteria, respectively, and 125 and 250 μg/ml of MIC for Aspergillus niger and Aspergillus flavus, respectively. In addition, ZnO-NPs showed antioxidant activity with IC₅₀ = 240 and 250 μg/ml by DPPH and ABTS, respectively. All concentrations of ZnO-NPs significantly improved the germination of barley seed and shoot height, with the optimum concentration reaching 2 and 12 ppm of ZnO-NPs for both seed germination (90%) and shoot height (6.5), respectively, while the greatest root extension (6 cm) was observed at 2 ppm of ZnO-NPs. The mitotic index increased at lower nanoparticle concentrations and exposure times but declined considerably as the nanoparticle dose and exposure duration increased, until most concentrations reached 100% suppression after 12 h with various chromosomal abnormalities. The researchers were able to create efficient, eco-friendly, and simple multifunctional ZnO-NPs using a green synthetic strategy and, in the process, obtain a better understanding of the cytotoxicity and genotoxicity of ZnO-NPs in plant cells.

Fusarium solani is a plant pathogenic fungus that causes tomato root rot disease and yield losses in tomato production. The current study’s main goal is testing the antibacterial efficacy of chitosan nanoparticles loaded with Thyme vulgaris essential oil (ThE-CsNPs) against F. solani in vitro and in vivo. GC-MS analysis was used to determine the chemical constituents of thyme EO. ThE-CsNPs were investigated using transmission electron microscopy before being physicochemically characterized using FT-IR. ThE-CsNPs were tested for antifungal activity against F. solani mycelial growth in vitro. A pot trial was conducted to determine the most effective dose of ThE-CsNPs on the morph/physiological characteristics of Solanum lycopersicum, as well as the severity of fusarium root rot. The relative gene expression of WRKY transcript factors and defense-associated genes were quantified in root tissues under all treatment conditions. In vitro results revealed that ThE-CsNPs (1%) had potent antifungal efficacy against F. solani radial mycelium growth. The expression of three WRKY transcription factors and three tomato defense-related genes was upregulated. Total phenolic, flavonoid content, and antioxidant enzyme activity were all increased. The outfindings of this study strongly suggested the use of ThE-CsNPs in controlling fusarium root rot on tomatoes; however, other experiments remain necessary before they are recommended.

Using agronomic parameters, ISSR (inter simple sequence repeat), and SCoT (start codon targeted) markers, ten potential wheat genotypes were examined for genetic diversity under normal and drought conditions. Significant agronomic features have been identified, as well as a low drought susceptibility index. Using seven SCoT and seven ISSR primers, a total of 112 amplified DNA fragments were synthesized, resulting in 61 and 51 bands, respectively. For SCoT and ISSRs, the percentage of polymorphism was 93.4% and 78.4%, respectively. Two markers, ISSR and SCoT, were found to be effective in detecting polymorphism among the examined genotypes, with mean PIC values of 0.61 and 0.62, respectively. In terms of marker index (MI), resolving power (Rp), and polymorphism percentage, SCoT markers exhibited the most significant values. The examination of seed storage proteins revealed 21 subunits with a mass ranging from 22 to 110 kDa. A cluster analysis of the data and morphological features contributed to identifying different molecular and biochemical bands that could be linked to genotype 4’s drought-resistance capabilities.

Cowpea (Vigna unguiculata (L.) Walp.) is the most important grain legume crop grown in tropical and subtropical regions. Seeds of cowpea have a high nutritional value containing high amount of protein (23–29%). Seeds of 19 landraces of cowpea (Vigna unguiculata) were obtained from gene bank of Cairo University (11 landraces) and from Agricultural Research Station Kafr El-Sheikh (Sakha) (8 varieties). The seeds planted till maturity. Random amplified polymorphic DNA (RAPD) was assayed to determine the genetic variation of 19 varieties of cowpea cultivated in different regions of Egypt. A total of five random primers were used in the study. Amplification of genomic DNA of Egyptian cowpea landraces with these RAPD primers yielded 54 fragments that could be scored, of which 45 were polymorphic. Number of amplified fragments with random primers ranged from 4 (OP 856) to 14 (OP 880). Percentage polymorphism ranged from 75% (OP 856) to a maximum of 100% (OP 889, OP 868, Op 808 and OP 880), with an average of 95%. A dendrogram produced by the Unweighted Pair Group Method with Arithmetic Mean (UPGMA) based on Jaccard‟s similarity coefficient revealed that the cowpea varieties divided into two groups which showed variability that may be exploited for crop improvement. The overall range of genetic similarities ranged from 0.48 to 0.93 in 19 landraces of cowpea which indicates there was high variability among the varieties. Based on genetic distance in RAPD analysis the landraces no. 9 and 12 appeared as most divergent and could be used in breeding programme of cowpea. It could be concluded that RAPD markers are important tools for genetic analysis for cowpea(Vigna unguiculata (L.) Walp.).