Taegro: A biofungicide with broad spectrum of activity towards soilborne or foliar fungal and bacterial pathogens. S. S. GNANAMANICKAM (1), S. Inman (1), L. West (1), S. Semones (1)
(1) Novozymes Biologicals, Salem, VA 24153
Phytopathology 98:S60

Abstract: Taegro is an EPA-registered biofungicide whose active ingredient is 5.0 × 10(^10) cfu/g of Bacillus subtilis var. amyloliquefaciens strain FZB24. It can be applied as soil drench or foliar spray at the rate of 2.5 to 3.5 oz per 100 gallons of water/A. Laboratory profiling of its bioefficacy in the laboratory has revealed that it has a wide spectrum of biological activity towards both fungal and bacterial pathogens. This includes the fungal pathogens, Rhizoctonia, Fusarium, Phytophthora (including mefenoxam-resistant field strains of P. erythroseptica) and Venturia inaequalis and strains of bacterial pathogens, Xanthomonas campestris, Pseudomonas syringae pathovars, Ralstonia solanacearum, and Erwinia amylovora. In greenhouse trials, we observed more than 75% reduction of bacterial wilt in tomato when Taegro was incorporated into the potting mix at the labeled rate of 1.23 g/gallon mix. Our laboratory and greenhouse observation are supported by crop data from field trials. In earlier field trials conducted during 1995–1998 treatment of tomatoes led to delay in Fusarium wilt development and also to 10-to-20% yield increases. In potatoes and ornamentals, FZB24 treatments led to consistent increase of tuber yield, marketable plants as well as number of flowers. From recent field trials conducted in different CA locations during 2007, significant disease reductions due to Taegro treatments were recorded for the suppression of (i) bacterial speck of tomato caused by Pseudomonas syringae pv. tomato (greater than that was afforded by kocide 2000), (ii) downy mildew of organic head lettuce caused by Bremia lactucae when compared to chemical standards, kaligreen and other conventional chemistry combinations, and (iii) bottom rot of lettuce caused by Rhizoctonia solani over the chemical standard botran 75-W. These results suggest that soil drench and foliar applications of Taegro show no phytotoxicity and can be reliably used to control fungal and bacterial pathogens.