Synergistic Effect of TiO2-Nanoparticles and Plant Growth-Promoting Microorganisms on the Physiological Parameters and Antioxidant Responses of Capsicum annum Cultivars Academic Article in Scopus uri icon

abstract

  • Titanium dioxide nanoparticles (TiO2-NPs) were synthesized using the molten salt method and systematically characterized. TiO2-NPs were evaluated for their capacity to promote the growth of Capsicum annuum cultivars together with the plant growth-promoting microorganisms (PGPMs) Bacillus thuringiensis (Bt) and Trichoderma harzianum (Th). The variables analyzed included physiological parameters and antioxidant responses. The capacity of TiO2-NPs to scavenge free radicals was also investigated, along with their biocompatibility, using Artemia salina as an in vivo model. The results demonstrated that TiO2-NPs exhibited a nanocuboid-type morphology, negative surface charge, and small surface area. It was noted that TiO2-NPs enhanced the CFU and spore production of Bt (1.56¿2.92 × 108 CFU/mL) and Th (2.50¿3.90 × 108 spores/mL), respectively. It was observed that TiO2-NPs could scavenge DPPH, ABTS, and H2O2 radicals (IC50 48.66¿109.94 ¿g/mL), while not compromising the viability of A. salina at 50¿300 ¿g/mL. TiO2-NPs were determined to enhance the root length and fresh and dry weights of chili peppers. Similarly, TiO2-NPs in synergy with Bt and Th increased the activity of ß-1,3-Glucanase (2.45 nkat/g FW) and peroxidase (69.90 UA/g FW) enzyme activity, and increased the TPC (29.50 GA/g FW). The synergy of TiO2-NPs with the PGPMs consortium also upregulated the total chlorophyll content: 210.8 ± 11.4 mg/mg FW. The evidence from this study unveils the beneficial application of TiO2-NPs with Bt and Th as an efficient approach to promote the physiology and antioxidant responses of chili peppers. © 2025 by the authors.

publication date

  • June 1, 2025