Efficacy of biopesticides and mixtures for control of Xanthomonas on ornamental plants
University of Florida
David Norman
IR-4 Ornamental Horticulture Program
Objective: The most common bacterial diseases among ornamental plants are caused by members of the: Erwinia, Pseudomonas, and Xanthomonas genera. Many of the products used to control bacterial diseases contain cupric hydroxide, mancozeb and antibiotics, which leave a heavy residue on plant surfaces and in some cases the use of the antibiotic, streptomycin sulfate, has promoted the development of resistant bacterial populations.
Method: During June, July, and Aug. of 2006, three tests were conducted on germaniums in order to determine which products, product combinations, and rotations might be effective in the control of Xanthomonas. Treatment included of one unsprayed disease control, three concentrations of Rhapsody, one applied with Kocide 2000, another with Penncozeb, and another with K-Phite. Also included, was one concentration of Actinovate and one concentration of Companion® Biological Fungicide.
Results: The research found that treatments containing copper hydroxide, copper sulfate and mancozeb were effective, as well as biologicals in combination with any of these active ingredients. While some product combinations were successful in reducing the amount of lesions per plant by 85% , Companion was an effective stand alone option reducing the amount of lesions by over 80%
Companion® is a registered trademark of Growth Products, Ltd. RHAPSODY® is a registered trademark of Agraquest. Kocide® is a registered trademark of DuPontTM. Penncozeb® is a registered trademark of United Phosphorus, Inc. K-Phite® is a registered trademark of Plant Food Systems. Actinovate® is a registered trademark of Natural Industries.