Utilizing bio-synthesis of nanomaterials as biological agents for controlling soil-borne diseases in pepper plants: root-knot nematodes and root rot fungus

Abstract

The utilization of Trichoderma longibrachiatum filtrate as a safe biocontrol method for producing zinc nanoparticles is a promising approach for managing pests and diseases in agricultural crops. The identification of Trichoderma sp. was achieved through PCR amplification and sequencing of 18s as ON203115, while the synthesis of ZnO-NPs was accomplished by employing Trichoderma filtration. The presence of ZnO-NPs was confirmed by observing a color change to dark green, along with the use of visible and UV spectrophotometers, and the formation and chemical structure of ZnO-NPs were examined. Direct exposure to ZnO-NPs exhibited a significant inhibitory effect on the growth of Fusarium oxysporum at 80.73% compared with control. Also, the percent mortality of Meloidogyne incognita second juveniles stage (J2s) results showed 11.82%, 37.63%, 40.86%, and 89.65% after 6, 12, 24, and 72 h, respectively in vitro. Disease resistance was assessed in the greenhouse against M. incognita and F. oxysporum using the drench application of ZnO-NPs. The application of ZnO-NPs significantly reduced the disease severity of F. oxysporum and improved the quality and quantity of sweet pepper yield. In addition, the application of ZnO-NPs to M. incognita resulted in a significant reduction in the number of nematode galls, egg masses per root, eggs/egg mass, and females by 98%, 99%, 99.9%, and 95.5% respectively.Furthermore, it was observed that the application of ZnO-NPs to pepper plants not only inhibited the growth of F. oxysporum and M. incognita, but also promoted the recovery of pepper plants as indicated by improvements in stem length by 106%, root length 102%, fresh weight 112%, root fresh weight 107%, and leaf area 118% compared to healthy control plants. Additionally, real-time PCR application and DD-PCR technique revealed that the application of ZnO-NPs stimulated the secretion of certain enzymes. These findings suggest that the biosynthesized ZnO-NPs possess anti-nematode and antifungal properties, making them effective for protecting plants against M. incognita and F. oxysporum invasion in soil. This study significantly contributes to our understanding of the nematicidal and fungicidal activities of ZnO-NPs in suppressing soil-borne diseases.

Trichoderma and Mycosynthesis of Metal Nanoparticles: Role of Their Secondary Metabolites

“…For the synthesis of Au-and Cu-based NPs, SMs of nitrogenous nature stand out [42,47,48,51]. Finally, carboxylic acids, amide, ester, ether, and phenolic compounds mediate the synthesis of ZnO NPs [52]. This information suggests that, depending on the type of MNPs, it will be the nature of the SMs that Trichoderma will be using.…”

“…However, further characterization is needed to determine which SMs are specifically responsible for mediating the synthesis, or at least to suggest candidates containing the identified functional groups. UV-vis, FTIR, EDX, XRD, SEM and TEM T. longibranchiatum [52] Abbreviations: Energy dispersive X-ray analysis (EDS); UV-vis spectroscopy (UV-vis); Fourier transform infrared spectroscopy (FTIR); X-ray diffraction (XRD); Transmission electron microscopy (TEM); Dynamic light scattering (DLS); Scanning electron microscopy (SEM); Energy dispersive Xray (EDAX); Particle size analyzer (PSA); Field emission scanning electron microscope (FESEM); High-resolution transmission electron microscope (HRTEM); X-ray photoelectron spectroscopy (XPS); Raman spectroscopy (Raman) and Photoluminescence (PL).…”

Exploring the Global Trends of Bacillus, Trichoderma and Entomopathogenic Fungi for Pathogen and Pest Control in Chili Cultivation

“… Abdelaziz et al (2022) Trichoderma longibrachiatum Meloidogyne incognita and F. oxysporum Zinc nanoparticles synthesized by Trichoderma longibrachiatum alter defense-related gene expression in chili plants and deform Fusarium oxysporum hyphae, causing them to lose smoothness, swell, and crumble. Ghareeb et al (2024) Trichoderma asperelloides and T. asperellum Colletotrichum gloeosporioides Trichoderma asperelloides SKRU-01 and T. asperellum NST-009 significantly inhibited the hyphal development of Colletotrichum gloeosporioides PSU-03 Boukaew et al (2024) Trichoderma harzianum Phytophthora capsici T. harzianum showed the highest antagonistic activity (42.86 % PICR) in vitro and was classified as class I on the Bell scale. Thus, along with three other Trichoderma spp., the species effectively controls the root necrosis caused by P. capsici in Manzano chili cultivation.…”

“…These mechanisms include the mycoparasitic activity of T. harzianum , its production of antibiotics, competition for nutrients and space, and its ability to penetrate and lyse the fusarial mycelium. Moreover, Ghareeb et al (2024) stated that the zinc nanoparticles synthesized by T. longibrachiatum exhibit both anti-nematode and antifungal properties, effectively protecting plants against Meloidogyne incognita and F. oxysporum , particularly in chili plants. These nanoparticles function by altering the expression of defense-related genes in the chili plant.…”