Comparative Performance of Fungicides, Biofungicides, Host-plant Defense Inducers, and Fertilizer in Management of Phytophthora Root Rot on Boxwood

Phytophthora root rot, caused by nicotianae Breda de Haan, is one of the destructive diseases boxwood ( Buxus sempervirens L.) and can affect all growth stages field- container-grown plants. Management a problem only possible through an integrated approach. In this study, efficacy fungicides, biofungicides, host-plant defense inducers, fertilizer were evaluated to manage rot boxwood. The objective experiment was develop fungicide biofungicide recommendations for management in production. Field greenhouse experiments conducted 2019 (Trial 1) 2020 2). field arranged completely randomized design with four plots per treatment five single ‘Green Velvet’ plants plot. treatment. Plots/containers inoculated P. grown on rice grains. Plant data such as height average width recorded at beginning end experiments. Total plant fresh weight Roots assessed disease severity using scale 0% 100% roots affected. Treatments used both fungicides—ametoctradin + dimethomorph, fluzapyroxad, mefenoxam, oxathiapiprolin, pyraclostrobin, pyraclostrobin boscalid; inducers—aluminum tris-drench, aluminum tris-foliar, potassium salts phosphoric acid; biofungicides— Trichoderma harzianum Rifai strain T-22 virens G-41, Bacillus amyloliquefaciens Priest; fertilizer—water-soluble nitrogen (nitrogen 5%) soluble potash; combination water-soluble nitrogen, potash, T. G-41. All treatments drench applied except tris, which foliar. controls nontreated, noninoculated experiments, that effectively reduced ametoctradin oxathiapiprolin. 5%), G-41 severity. Oxathiapiprolin are chemical fungicides effective