099: Compatibility Test – How Do Biologicals Fit Into Your Spray Program with Katie Gold & Dave Combs

About this episode

Dr. Katie Gold and Dave Combs discuss the integration of biological fungicides into spray programs for winegrape growers.

Dr. Katie Gold and Dave Combs from Cornell University join Fritz to unpack one of the most confusing topics facing winegrape growers today: how biological fungicides truly fit into a spray program. Katie explains how the Cornell grape pathology program has expanded rapidly, moving from strictly conventional efficacy trials into extensive work with biologicals as more of these products come out of R&D pipelines. She outlines why growers can't rely on "the next new conventional" anymore and how biologicals are becoming essential tools for sustainable disease management and resistance stewardship. Dave brings decades of field experience and shares how his initial skepticism about biologicals shifted after seeing modern products perform on highly disease‑prone varieties in one of the toughest vineyards for powdery mildew, downy mildew, black rot, and bunch rots. Together, they walk through what "compatibility" really means and why water pH, formulation, and whether an organism is alive or dead matter far more than many growers realize. Listeners learn why mixing biologicals and conventionals in the same tank often provides no added control (and may waste money), where negative…

People in this episode

Host: Fritz Westover

Guests: Dr. Katie Gold, Dave Combs

Topics covered

• biological fungicides
• spray program
• sustainable disease management
• winegrape growers
• compatibility in agriculture

Keywords

• biologicals
• fungicides
• sustainable agriculture
• disease management
• winegrape
• Cornell grape pathology
• powdery mildew
• downy mildew

Mentioned in this episode

Organizations: Cornell University

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