Because of their broad applications in our life, nanoparticles are expected to be present in the environment raising many concerns about their possible adverse effects on the ecosystem of plants. The aim of this study was to examine the effect of different sizes and concentrations of iron oxide nanoparticles [(Fe3O4) NPs] on morphological, physiological, biochemical, and ultrastructural parameters in tobacco (Nicotiana tabacum var.2 Turkish). Lengths of shoots and roots of 5 nm-treated plants were significantly decreased in all nanoparticle-treated plants compared to control plants or plants treated with any concentration of 10 or 20 nm nanoparticles. The photosynthetic rate and leaf area were drastically reduced in 5 nm (Fe3O4) NP-treated plants of all concentrations compared to control plants and plants treated with 10 or 20 nm (Fe3O4) NPs. Accumulation of sugars in leaves showed no significant differences between the control plants and plants treated with iron oxide of all sizes and concentrations. In contrast, protein accumulation in plants treated with 5 nm iron oxide dramatically increased compared to control plants. Moreover, light and transmission electron micrographs of roots and leaves revealed that roots and chloroplasts of 5 nm (Fe3O4) NPs-treated plants of all concentrations were drastically affected. The size and concentration of nanoparticles are key factors affecting plant growth and development. The results of this study demonstrated that the toxicity of (Fe3O4) NPs was clearly influenced by size and concentration. Further investigations are needed to elucidate more about NP toxicity in plants, especially at the molecular level.

Salinity is one of the major problems facing crops worldwide. Salinity can severely affect plants in a negative manner. This study aimed to evaluate the impact of NaCl on morpho–physiological, biochemical, structural and ultrastructural properties in Solanum melongena seedlings under different NaCl concentrations. Plants treated with high concentrations of NaCl showed a nonsignificant decrease in shoot height compared to the controls. However, NaCl concentration of 50 mM and above significantly decreased leaf area, while 75 mM and above significantly reduced the photosynthetic rate (PN) and leaf total sugar content when compared with plants treated with less-concentrated NaCl and the controls. Thick root sections from plants grown in 100 and 150 mM NaCl exhibit severe deformation in the epidermal and cortical layers. Additionally, TEM micrographs of plants treated with 75, 100, and 150 mM exhibited bulgy chloroplasts with loss of integrity thylakoid membranes associated with large starch grains. The changes in plant ultrastructure observed in this study broaden our knowledge about the impact of salinity at the cellular level.

The pivotal Cleome arabica L. species belongs to the Cleome genus with fascinating secondary metabolites consisting of main classes of phenols, flavonoids, and glucosinolate derivatives. The current study was carried out on three crude extracts of Cleome arabica L. plant of Jordanian origin. In terms of the valuable resources for natural new drug development. The phytochemical contents, antioxidants, and antibacterial activities, in addition to the oil composition of this species were identified. Forty-six compounds representing 96.98% of the total composition were detected from the essential oil obtained by hydrodistillation (0.06%). The oil composition was dominated by nitrogen-sulfur-containing compounds (35.66%), esters (19.64%), and oxygenated sesquiterpenes (11.92%). Butanol extract had significantly the best scavenging activities of DPPH (P < .0001), ABTS (P < .0001), and hydroxyl radicals (P < .0001) while the Aq.MeOH extract exhibits the highest flavonoid content (173.5 ± 0.002 mg Quercetin/g dry extract) and had significantly the most ferrous chelating effect (P = .0011). Also, most of the tested extracts showed antibacterial activities against bacterial strains. Our findings exhibited that the Cleome arabica L. plant from Jordan origin might be a good candidate as potential biologically compounds that could be used as a source of natural antioxidants and antibacterial agents.