Wheat aphid, Sitobion avenae (Fab.), is a serious pest of wheat crop across the world. The present study was conducted to evaluate the potentials of the water plant extracts of Azadirachta indica (neem) or Eucalyptus camaldulensis and the entomopathogenic fungi (EPF); Beauveria bassiana or Metarhizium anisopliae against the aphid species. After 5 days of applications, the combined mixture of B. bassiana and eucalyptus extract caused the maximum mortality rate (87%). While the combination of B. bassiana with neem extract showed the least rate (54%). Fecundity was negatively affected by the single and combined treatments of EPF and botanicals extracts. The lowest fecundity (7 nymphs per female) was recorded when the aphid was treated by the binary mixture of B. bassiana and eucalyptus extract. Correspondent maximum fecundity (29 nymphs per female) in 5 days was recorded in control treatment, while 23 nymphs were produced by a single female when treated with the binary mixture of B. bassiana and neem extract. The results indicated that EPF and botanical extracts (neem or eucalyptus) caused significant reduction in survival and fecundity of S. avenae. Therefore, they may be used as promising natural alternatives to synthetic insecticides against the wheat aphid species.

Using plant extracts as eco-friendly reducing and stabilizing agents for the synthesis of nanoparticles has gained significant attention in recent years. The current study explores the green synthesis of silver nanoparticles (AgNPs) using the Avena fatua extract and evaluates their antifungal activity against Fusarium oxysporum f.sp. lycopersici (Fol), a fungal plant pathogen. A green and sustainable approach was adopted to synthesize silver nanoparticles before these nanoparticles were employed for anti-fungal activity. The primary indication that AgNPs had formed was performed using UV-vis spectroscopy, where a strong peak at 425 nm indicated the effective formation of these nanoparticles. The indication of important functional groups acting as reducing and stabilizing agents was conducted using the FTIR study. Additionally, morphological studies were executed via SEM and AFM, which assisted with more effectively analyzing AgNPs. Crystalline behavior and size were estimated using powder XRD, and it was found that AgNPs were highly crystalline, and their size ranged from 5 to 25 nm. Synthesized AgNPs exhibited significant antifungal activity against Fol at a concentration of 40 ppm. Furthermore, the inhibitory index confirmed a positive correlation between increasing AgNPs concentration and exposure duration. This study suggests that the combined phytochemical mycotoxic effect of the plant extract and the smaller size of synthesized AgNPs were responsible for the highest penetrating power to inhibit Fol growth. Moreover, this study highlights the potential of using plant extracts as reducing and capping agents for the green synthesis of AgNPs with antifungal properties. The study concludes that A. fatua extract can synthesize antifungal AgNPs as a sustainable approach with robust antifungal efficacy against Fol, underscoring their promising potential for integration into plant protection strategies.

The fall armyworm, Spodoptera frugiperda (Noctuidae; Lepidoptera), is a serious threat to food security as it has the potential to feed on over 353 plant species. To control this insect pest, endophytic colonization of entomopathogenic fungi (EPF) in plants is being considered as a safer and more effective alternative. This study evaluated the efficacy of two EPFs, Beauveria bassiana and Metarhizium anisopliae, for endophytic colonization using foliar spray and seed treatment methods on maize plants, and their impact on the survival, development, and fecundity of S. frugiperda. Both EPF effectively colonized the maize plants with foliar spray and seed treatment methods, resulting in 72–80% and 50–60% colonization rates, respectively, 14 days after inoculation. The EPF negatively impacted the development and fecundity of S. frugiperda. Larvae feeding on EPF-inoculated leaves had slower development (21.21 d for M. anisopliae and 20.64 d for B. bassiana) than the control treatment (20.27 d). The fecundity rate was also significantly reduced to 260.0–290.1 eggs/female with both EPF applications compared with the control treatment (435.6 eggs/female). Age-stage-specific parameters showed lower fecundity, life expectancy, and survival of S. frugiperda when they fed on both EPF-inoculated leaves compared with untreated leaves. Furthermore, both EPFs had a significant effect on population parameters such as intrinsic (r = 0.127 d⁻¹ for B. bassiana, and r = 0.125 d⁻¹ for M. anisopliae) and finite rate (λ = 1.135 d⁻¹ for B. bassiana, and λ = 1.1333 d⁻¹ for M. anisopliae) of S. frugiperda compared with the control (r = 0.133 d⁻¹ and λ = 1.146 d⁻¹). These findings suggest that EPF can be effectively used for the endophytic colonization of maize plants to control S. frugiperda. Therefore, these EPFs should be integrated into pest management programs for this pest.