Biocontrol-based Eco-friendly Management of Fusarium Wilt in Carnation: A Review

Biocontrol-based eco-friendly management is not merely the substitution of a chemical input with a microbial product. Rather, it involves aligning multiple biological mechanisms—competition for nutrients and infection sites, antibiosis, mycoparasitism, modification of the rhizosphere microbiome, and plant defense priming—within the specific constraints of carnation production systems. Fusarium wilt of carnation (Dianthus caryophyllus L.), caused by Fusarium oxysporum f. sp. dianthi (Fod), remains one of the most destructive constraints in commercial carnation cultivation, particularly under intensive protected production where soil fatigue, repeated monoculture, and high inoculum pressure amplify losses. Conventional control historically relied on soil disinfestation and fungicides, but environmental concerns, regulatory restrictions, and inconsistent field performance have accelerated interest in eco-friendly biocontrol solutions. This review synthesizes advances in biological and microbiome-informed management of carnation Fusarium wilt, with emphasis on antagonistic fungi (notably Trichoderma spp.), plant growth–promoting rhizobacteria (PGPR) including Pseudomonas and Bacillus, suppressive composts and organic amendments, and the strategic use of non-pathogenic Fusarium strains. We evaluate evidence for key modes of action—competition, antibiosis, mycoparasitism, induced systemic resistance/priming, interference with pathogen virulence, and engineered suppressiveness through substrates and microbial consortia. Carnation-specific studies demonstrate that compost-based media and targeted Trichoderma selections can markedly reduce disease, while population genetic tools and race diagnostics enable more rational deployment of biocontrol and host resistance. The review also highlights formulation and delivery constraints unique to ornamental systems, including propagation-stage interventions, substrate microbiology, and compatibility with fertigation and hygiene protocols. Finally, we propose a framework for integrated, residue-minimising management that combines clean planting material, diagnostic surveillance, suppressive substrates, and robust microbial products tailored to Fod population structure and production ecology.