Table 3.

The influence of nanoparticles on plant pathogenic bacteria

NPs	Source	Targeted pathogen	Order/ Family	Effects	References
Ag	Cannabis sativa extracts	Pseudomonas syringae pv. tomato	Pseudomonadales/Pseudomonadaceae	Silver nanoparticles containing 90% lower silver content compared to the un-dialyzed silver salt (Ag-UD) exhibited at least 20% more inhibition	[237]
	AgNO3 and NaBH4	Ralstonia solanacearum	Burkholderiales/Burkholderiaceae	Silver nanoparticles formed in EPS1 solution exhibited a concentration-dependent inhibition of bacteria. Silver nanoparticles at 0.8 mg/mL have been shown to have antibacterial activity but a very low cytotoxicity on the RAW264.7 murine macrophage cells	[238]
	Moringa oleifera	Xanthomonas axonopodis pv citri	Xanthomonadales/Xanthomonadaceae	Biosynthesised AgNPs at different concentrations (10, 20, 30, and 40 ppm) were exogenously applied on the already infected plants (canker) of Citrus reticulata at different day intervals. The AgNPs at a concentration of 30 ppm was found to be the most effective concentration against citrus canker	[226]
	Bacillus cereus SZT1cereus SZT1	Xanthomonas oryzae pv. oryzae	Xanthomonadales/Xanthomonadaceae	Silver nanoparticles showed substantial antibacterial potency (24.21 ± 1.01 mm) for Xanthomonas oryzae pv. Oryzae	[228]
	polyvinylpyrrolidone with metallic silver	Candidatus liberobacter	Hyphomicrobiales/Rhizobiaceae	The AgNPs were applied by foliar sprinkling and trunk injection of 93 diseased trees with remarkable results. Both methods produce an 80–90% decrease of bacterial titre	[227]
	Aqueous extract of strawberry waste	Ralstonia solanacearum	Burkholderiales/Burkholderiaceae	A strong inhibition zone was found around the paper disc dipped in 100 µg/mL AgNPs, placed in NA media inoculated with R. solanacearum and the inhibition zone was absent around the control disc	[239]
	Dioscorea bulbifera	Bacillus sp.	Bacillales/Bacillaceae	Inhibition zone ranged from 6.00 ± 0.41 to 11.00 ± 0.87 mm was observed at a concentration of 100 ppm	[240]
		Enterobacter cloacae	Enterobacterales/Enterobacteriaceae
	Penicillium simplicissimum, Aspergillus niger, and Fusarium oxysporum	Pectobacterium carotovorum	Enterobacterales/Enterobacteriaceae	Inhibition zone was found up to 15.3 mm at a concentration of 100 ppm	[241]
	Larrea tridentata	Clavibacter michiganensis	Micrococcales/Microbacteriaceae	The disease incidence did not exceed 20%, reduced disease severity by 36%, inhibition of bacterial growth in the tissue (up to 95%)	[242]
	Eucalyptus globulus	Xanthomonas citri pv. Citri	Xanthomonadales/Xanthomonadaceae	AgNPs and CuNPs in combination showed maximum growth inhibition (21.06 mm) followed by AgNPs (18.26 mm) and CuNPs (15.27 mm)	[243]
Au	Olea europaea fruit extract, Acacia nilotica and husk extract	Pseudomonas spp	Pseudomonadales/Pseudomonadaceae	AuNPs expressed moderate antibacterial activity and inhibition zone up to 8 mm was found	[244]
	Phoma sp.	Xanthomonas oryzae pv. Oryzae	Xanthomonadales/Xanthomonadaceae	Inhibition rate for sclerotia formation was (15, 33, 74 and 93% at concentrations (10, 20, 40 and 80) μg/mL of AuNPs respectively	[245]
Zn	Morus alba plant leaf extract	Xanthomonas axonopodis pv. Malvacearum	Xanthomonadales/Xanthomonadaceae	These NPs was found to be very effective in controlling the bacterial spread in comparison to streptomycin that was used as control	[246]
	Sigma-Aldrich, Steinheim	P. syringae	Pseudomonadales/Pseudomonadaceae	An inhibition zone of 0.72 mm was observed at concentration of 0.10 mg/mL ZnO NP discs on plates inoculated with Pectobacterium carotovorum	[247]
	Matricaria chamomilla L., Olea europaea and Lycopersicon esculentum M	Xanthomonas oryzae pv. Oryzae	Xanthomonadales/Xanthomonadaceae	ZnONPs synthesized by Olea europaeahad the highest inhibition zone of 2.2 cm at concentration of 16 mg/mL	[233]
	Green tomato extract	Xanthomonas oryzae pv. oryzae	Xanthomonadales/Xanthomonadaceae	Zinc oxide nanoparticles powder at the concentration of 4.0, 8.0, and 16 μg/mL expressed an inhibitory zone of 2.4, 2.6, and 2.9 cm, compared with that of 1.4, 1.5, and 1.8 cm from bulk zinc oxide, respectively	[248]
	Matricaria chamomilla	Ralstonia solanacearum	Burkholderiales/Burkholderiaceae	At concentration of 18 µg/mL, Zinc oxide nanoparticles showed the highest inhibition area of 22.3 mm	[249]
	Bacillus cereus RNT6	Burkholderia glumae	Burkholderiales/Burkholderiaceae	At 50 µg/mL concentration, pathogen growth was reduced by 71.2%	[250]
		B. gladioli
	Withania coagulans	Ralstonia solanacearum	Burkholderiales/Burkholderiaceae	Highest inhibitory area of 16.2 mm was exhibited at highest concentration (80 μg/mL) of ZnONPs + leaf extract	[251]
Cu	Shell copper and Multivalent copper	Xanthomonas perforans	Xanthomonadales/Xanthomonadaceae	Cu-composites significantly decrease disease severity, using 80% less metallic copper in comparison with Cu-mancozeb in field evaluation (P < 0.05)	[252]
	Datura Innoxia	Xanthomonas oryzae pv. Oryzae	Xanthomonadales/Xanthomonadaceae	CuNPs exhibited effective antibacterial potency against Xanthomonas oryzae pv. oryzae with mean inhibition zone of approximately 18 mm	[234]
	Carica papaya	Ralstonia solanacearum	Burkholderiales/Burkholderiaceae	After an initial incubation (12 h), NPs posed no effect on biofilm. Maximum inhibition (35% and 37%) was observed at dosage of 125 and 250 μg/mL at 24 h and 12% and 38% reduction in biofilms at 72 h respectively	[253]
	Eucalyptus globulus	Xanthomonas citri pv. Citri	Xanthomonadales/Xanthomonadaceae	AgNPs + CuNPs exhibited maximum inhibitory area of 21.06 mm followed by AgNPs 18.26 mm and CuNPs 15.27 mm	[243]