Fungicide Sprays affect Leaf Condition and Tree Appearance of Southern Magnolia
William D. Goff, Ronald L. Shumack, Ken M. Tilt, and Austin K. Hagan
Abstract: Several fungicides and chemical combinations were sprayed on southern magnolia trees to improve leaf condition and tree appearance. Leaf spot and leaf scorch symptoms, induced by the fungus Glomerella cingulata, were reduced significantly by sprays with benomyl, chlorothalonil, propiconazole, myclobutanil, or copper hydroxide. Addition of a non-ionic surfactant in sprays resulted in phytotoxicity, visible as a ring spot or faded brown patch on leaves. Tank mixing of copper hydroxide with other fungicides also increased phytotoxicity and did not improve disease control or leaf condition. Benomyl and propiconazole treatments were among the best in improving overall tree appearance.