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Poster: Biology & Disease Mgmt: Chemical Control


Optimizing the systemicity of triazole formulations by enhancing leaf penetration
G. POON (1), C. Irwin (2), J. Dinglasan (2), N. Loukine (1) (1) Vive Crop Protection, Canada; (2) Vive Crop Protection, Canada

The systemicity of a fungicide plays a vital role in its performance. While the ability of a fungicide to penetrate the leaf cuticle and translocate through plant tissue is active specific, inert formulation ingredients can optimize these processes on target crops. Triazoles and strobilurins are broad spectrum fungicides with known systemicity; however, in lab testing only a small fraction of applied active ingredient was able to penetrate a synthetic membrane that mimics a leaf cuticle. Fungicide formulations that are optimized for membrane penetration may have enhanced disease control over existing formulations. Laboratory trials were conducted using a Franz cell fitted with a synthetic membrane to identify experimental formulations that may have better leaf cuticle penetration than the commercial product. Field trials were conducted in 2015 to evaluate the efficacy of experimental tebuconazole formulations on powdery mildew in acorn squash. All tebuconazole treatments were applied weekly at label rate following disease onset for a total of four applications. While yield did not differ statistically between any of the treatments, an experimental formulation significantly reduced disease severity by 40.5% relative to the commercial product and 55.3% relative to the untreated control. From the positive field results achieved by enhancing leaf cuticle penetration, further field and lab testing to optimize performance will be completed.