Baysal-Gurel F and Kabir N
Rhizoctonia root rot disease is one of the destructive diseases of woody ornamentals with a wide host range. In this study the efficacy of biocontrol products and fungicides against Rhizoctonia root rot of Viburnum odoratissimum was assessed in a separate greenhouse and field experiments. Treatments used in both experiments were RootShield PLUS+, MBI110, SoilGard, IT-5103, TerraClean 5.0+TerraGrow program, Mural, Empress Intrinsic and Paegant Intrinsic. Pots/plots were inoculated with Rhizoctonia solani agar slurry. Non-treated, non-inoculated and inoculated pots/plots served as controls. In both greenhouse and field experiments, all the treatments significantly reduced Rhizoctonia root rot severity. The treatments most effective in reducing Rhizoctonia root rot severity were Mural, Empress Intrinsic, Paegant Intrinsic and TerraClean 5.0+TerraGrow program in both greenhouse and field experiments compared to the other treatments and non-treated, inoculated control. Phytotoxicity and defoliation were not observed in any of the viburnum plants. This study will help nursery producers make proper management decisions by using recommended fungicides and biocontrol products of this study in a rotation or alone to manage Rhizoctonia root rot diseases of viburnum.