The last two decades have seen the discovery of novel retroviruses that have resulted in severe negative consequences for human health. In late 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged with a high transmission rate and severe effects on human health, with 5% infected persons requiring hospitalisation and 3.81 million deaths to date globally. Aerosol particles containing virions are considered the main source of SARS CoV-2 transmission in this pandemic, with increased infection rates in confined spaces. Consequently, public and private institutions had to institute mitigation measures including the use of facial masks and social distancing to limit the spread of the virus. Moreover, the role of air purification and bio-decontamination is understood as being essential to mitigate viral spread. Various techniques can be applied to bio-decontaminate the air such as the use of filtration and radiation; however, these methods are expensive and not feasible for home use. Another method of air purification is where indoor plants can purify the air by the removal of air pollutants and habituated airborne microbes. The use of indoor plants could prove to be a cost-efficient way of indoor air-purification that could be adapted for a variety of environments with no need for special requirements and can also add an aesthetic value that can have an indirect impact on human health. In this review, we discuss the emergence of the COVID-19 pandemic and the currently used air purification methods, and we propose the use of indoor plants as a new possible eco-friendly tool for indoor air purification and for reducing the spread of COVID-19 in confined places.

In the current study, we used high-performance liquid chromatography (HPLC) and gas chromatography–mass spectrometry (GC–MS) to investigate and analyze the methanolic extract of Salvia rosmarinus leaves. HPLC analysis showed that the extract revealed a diverse array of polyphenolic compounds, including apigenin, catechin, chlorogenic acid, cinnamic acid, caffeic acid, coumaric acid, daidzein, ellagic acid, ferulic acid, gallic acid, hesperetin, kaempferol, methyl gallate, naringenin, pyrocatechol, quercetin, rutin, syringic acid, and vanillin. Furthermore, three fungal isolates from symptomatic strawberry plants were obtained and identified as Botrytis cinerea (OR116486), Fusarium oxysporum (OR116505), and Rhizoctonia solani (OR116525). The extract’s antifungal activity was evaluated at concentrations of 0, 50, 150, 200, and 300 µg/mL. At 200 µg/mL, the extract showed growth inhibition percentages of 74.56, 58.19, and 56.67% for R. solani, F. oxysporum, and B. cinerea, respectively, while at 300 µg/mL, all the tested fungi were completely suppressed. The GC–MS analysis revealed that the major compounds of the methanolic extract identified based on their retention times and relative peak areas (%) included β-caryophyllene (12.06%), germacrene d (13.55%), caryophyllene oxide (3.13%), methyl palmitate (5.26%), hexadecanoic acid (4.9%), and methyl stearate (6.02%). These results show rosemary extract’s potential as a source of natural antifungal agents against plant photogenic fungi. As a result, it provides a safer alternative to the current protective approaches for plant disease management.

Nanoscale materials are promising tools for managing plant diseases and are becoming important players in the current agritech revolution. However, adopting modern methodologies requires a broad understanding of their effectiveness in solving target problems and their effects on the environment and food chain. Furthermore, it is paramount that such technologies are mechanistically and economically feasible for growers to adopt in order to be sustainable in the long run. This Feature Article summarizes the latest findings on the role of nanoscale materials in managing agricultural plant pathogens. Herein, we discussed the benefits and limitations of using nanoscale materials in plant disease management and their potential impacts on the environment and global food security.

The increasing impacts of climate change, global warming, and water scarcity are intensifying drought risk and compromising global food security. To mitigate these challenges, green-synthesized nanoparticles (NPs) derived from plant extracts have recently emerged as an innovative tool for enhancing crop resilience to abiotic stresses such as drought. Moringa enables eco-friendly nanoparticle production with diverse uses. Although Moringa enhances plant traits and its NPs have antimicrobial properties, limited research exists on their ability to improve plant tolerance to abiotic stress. Here, we investigated the potential of copper oxide (CuO) nanoparticles synthesized from Moringa plant extracts to alleviate drought stress in tomato plants (Solanum lycopersicum). The Moringa-based CuO NPs were characterized via UV‒Vis spectrophotometry, Zeta potential, FTIR, SEM, and TEM. Foliar applications of the NPs at various concentrations (3, 6, and 9 mg/L) were tested on tomato seedlings under normal and drought-induced conditions (10% PEG), alongside two controls: non-stressed control (water treatment) and drought stress control (PEG treatment). Physiological assessments showed that 6 mg/L Moringa-based CuO NPs were most effective under drought stress, significantly reducing leaf yellowing and increasing shoot length by 11%, root length by 21%, total dry biomass by 34% increase, and total chlorophyll content by 32% increase at (p < 0.05) compared to the drought stress control. Furthermore, at the molecular level, gene expression analysis revealed the upregulation of PAL, CHS, and HQT, which are genes critical to the stress response and secondary metabolism in tomato plants. Notably, the combination of CuO NPs with PEG amplified gene expression, indicating a synergistic effect on improving drought tolerance. These findings highlight the potential of the use of Moringa-synthesized CuO nanoparticles as a sustainable, eco-friendly strategy to mitigate drought stress in economic crops such as tomatoes. This new green approach offers a promising solution for bolstering food security in the face of climate change and water scarcity challenges.

Plant viruses are one of the most economically important plant pathogen groups in the world, and there is no viricide available for their control. Therefore, RNA interference (RNAi)-based crop protection has become a promising strategy for the control of viral plant pathogens in agricultural systems. Herein, we aimed to test the hypothesis that exogenously applied dsRNA molecules derived from different viral genomic regions induce different levels of viral suppression by RNAi in plants. We also evaluated the fate and movement of the dsRNA molecules inside tobacco plants. We synthesized dsRNAs from three potato virus Y (PVY) cistrons, helper component-protease (HC-Pro), nuclear inclusion protein b (NIb), and coat protein (CP), and applied them to tobacco leaves to test our hypothesis. Our results indicated that all three dsRNAs applied can provide some level of protection to plants against PVY infection. However, the intensity and longevity of protection depend on the type of dsRNA applied. HC-Pro-dsRNA induced greater protection, entered, and moved faster in tobacco plants than dsRNAs from NIb and CP cistrons. Furthermore, dsRNAs were detected in systemic leaves after 24 h of dsRNA application and remained for at least 14 days, demonstrating that these molecules translocated systemically inside the plant. The synthesis and application of exogenous dsRNAs targeting the HC-Pro genomic region of PVY appear to be a promising strategy for controlling PVY. Moving forward, we are working on developing a delivery system to sustainably provide plants with those molecules to create viricides for practical agricultural applications. Potato virus Y (PVY) causes severe yield and production losses in various Solanaceae family members, e.g., potatoes, tobacco, and tomatoes. In our studies, we conducted virus-derived small interfering RNA (vsiRNA) mapping analyses and chose those genomic regions with highly abundant vsiRNAs, denominated “vsiRNA hotspots”, to guide the selection of regions for dsRNA synthesis. We found that HC-Pro-dsRNA provided greater plant protection against PVY infection than CP-dsRNA and NIb-dsRNA. This can be explained by our finding that HC-Pro-dsRNA enters and moves faster inside the plant than the other dsRNAs tested, indicating that the genomic region matters when synthesizing dsRNA for plant virus suppression via RNAi. Furthermore, we demonstrated that the movement of these molecules inside the plants can occur both in the form of dsRNAs and vsiRNAs. Our study sheds important light on developing RNAi-based technologies to control plant viruses that could translate into field applications.

Fusarium wilt, caused by Fusarium oxysporum f. sp. lycopersici , threatens global tomato production, with losses reaching 80%. Although chemical fungicides are effective, their prolonged use risks resistant strains, reduces soil biodiversity, and causes environmental damage, highlighting the urgent need for ecofriendly alternatives. This study investigated the viability of Salvia officinalis (sage) methanolic extract as a biocontrol agent against Fusarium wilt (FW), employing a comprehensive approach that incorporates in vitro, in vivo, and molecular docking techniques. Four distinct isolates of F. oxysporum were identified through molecular techniques, and their virulence was assessed by examining the presence of tomatinase genes. The antifungal properties of S. officinalis extract were found to be compelling, with a total phenolic content of 64.15 mg GAE/g and a remarkable antioxidant activity of 97.04%. In laboratory tests, S. officinalis exhibited potent antifungal activity, inhibiting mycelial growth by between 52.00% and 88.67% at a concentration of 20 mg/ml. Additionally, in vivo experiments demonstrated a significant reduction in disease severity in treated tomato plants. Molecular docking analyses revealed strong binding affinities between key phytochemicals in the extract and target receptors such as tomatinase, highlighting the potential of the extract as a sustainable and effective alternative to chemical fungicides for managing FW in tomato crops.