Synergistic Antifungal Activity of Graphene Oxide and Fungicides against Fusarium Head Blight In Vitro and In Vivo

Abstract

Plant pathogens constantly develop resistance to antimicrobial agents, and this poses great challenges to plant protection. Therefore, there is a pressing need to search for new antimicrobials. The combined use of antimicrobial agents with different antifungal mechanisms has been recognized as a promising approach to manage plant diseases. Graphene oxide (GO) is a newly emerging and highly promising antimicrobial agent against various plant pathogens in agricultural science. In this study, the inhibitory activity of GO combined with fungicides (Mancozeb, Cyproconazol and Difenoconazole) against Fusarium graminearum was investigated in vivo and in vitro. The results revealed that the combination of GO and fungicides has significant synergistic inhibitory effects on the mycelial growth, mycelial biomass and spore germination of F. graminearum relative to single fungicides. The magnitude of synergy was found to depend on the ratio of GO and fungicide in the composite. In field tests, GO–fungicides could significantly reduce the disease incidence and disease severity, exhibiting a significantly improved control efficacy on F. graminearum. The strong synergistic activity of GO with existing fungicides demonstrates the great application potential of GO in pest management.

Graphene Oxide Exhibits Antifungal Activity against Bipolaris sorokiniana In Vitro and In Vivo

“…For example, fungicide-resistant strains emerge after long-term use [ 27 ]. Graphene application has provided a new tool for controlling plant pathogens [ 19 ]. Recent findings have demonstrated that graphene’s antimicrobial activities are greatly influenced by its physical and chemical properties, such as functional groups [ 52 ], concentration [ 53 ] and morphology [ 53 ].…”

“…We found that the inhibitory effect of graphene was concentration-dependent; at low concentrations (50, 100 mg/L), its inhibitory effect is limited, while at high concentrations (200, 500 mg/L), its inhibitory effect is significant. Previous studies have suggested that graphene can not only inhibit the growth of many pathogens by itself but also has a synergistic effect with fungicides [ 12 , 14 , 19 ]. It has been demonstrated that GO can significantly hinder the growth of mycelium and the germination of a variety of fungal pathogen spores afflicting plants, including Fusarium graminearum , Fusarium poaea , and Fusarium oxysporum [ 54 ].…”

“…It has been used extensively in more and more areas, such as biomedicine [ 3 ], nanoelectronic equipment [ 4 ], energy storage [ 5 ], gene delivery [ 6 ], cell imaging [ 7 ], tissue engineering [ 8 ], and agroforestry [ 9 , 10 , 11 ]. Recently, many studies have revealed graphene’s role in antimicrobial activity [ 12 , 13 , 14 , 15 , 16 , 17 ], laying the groundwork for its subsequent use in controlling disease pathogens [ 18 , 19 ].…”

Nanopesticide Formulation from Pyraclostrobin and Graphene Oxide as a Nanocarrier and Application in Controlling Plant Fungal Pathogens

“…First, GO was prepared with the Hummer’s method [ 27 ]. Physical loading of Pyr onto the surface of GO was conducted to obtain the GO–Pyr nanocomposite [ 28 ]. For screening the optimal combination ratio between GO and Pyr, the inhibitory effects of GO–Pyr combined at different ratios (1:9, 2:8, 3:7, 6:4, 5:5, 4:6, 7:3, 8:2 and 9:1) on the mycelial growth of FG was tested.…”

Advances in Biologically Applicable Graphene-Based 2D Nanomaterials

“…GO combined with mancozeb, cyproconazol, and difenoconazole fungicides exhibited synergistic inhibitory effects on the mycelial growth and biomass as well as spore germination of F. graminearum compared to single fungicides, and also in a field experiment pronouncedly reduced Fusarium head blight disease incidence and disease severity in wheat plants. Upon GO-fungicide treatment, mycelia were shrunk and deformed, and membrane fusion, due to the changes in cell membrane permeability and loss of cell wall integrity, along with disappearance of cytoplasm, was observed [ 201 ]. The IC 50 value related to the inhibition of mycelium growth of Magnaporthe oryzae by carbendazim−GO nanocomposite was 0.28 μg/mL, compared to 0.64 μg/mL estimated at single carbendazim application, suggesting 2.29-fold higher antifungal activity.…”