“Every meal you eat has passed through a farm that used some form of antimicrobial to keep pathogens off the crop. Most of that chemistry is designed with no thought about resistance – that gap is what I wanted to work on.”

Barcley Rohrlach is a SAAFE Scholar at The University of Queensland’s School of Agriculture and Food Sustainability, whose research focuses on a multifunctional crop coating built from food-grade and agricultural materials. Supervised by Dr Alberto Baldelli, Dr Yosephine Gumulya and Professor Mark Turner, with Dr Ganesh Kokil on the industry side from project partner AgroBest, Barcley is developing a spray-on coating designed to do three things at once: knock down bacterial pathogens, manage sunlight and UV to protect against abiotic stress, and stay on the leaf when it rains.

Barcley completed a Bachelor of Science in Biochemistry, Molecular Biology and Chemistry at Griffith University, with a capstone project synthesising candidate antimalarial compounds, followed by a Graduate Certificate in Molecular Biology at UQ. He brings more than a decade of industry experience to his research from AgroBest, where he worked his way up to R&D Manager and ran some 60 projects from idea to shelf. These projects spanned microbial inoculants, hydrolysed plant peptides and a wide range of biostimulants with a focus on finding the best solution for the farmer.

At SAAFE CRC, Barcley’s project extends the polymer coating he has worked on commercially, pushed in a more mechanistic, renewable and food-grade direction. Current days are spent building the decision frameworks for the formulation, with bench planning, reading, supervisor meetings and writing; later in the project the work shifts to spraying coatings on real crops, running pathogen assays and measuring leaf gas exchange.

Barcley was drawn to antimicrobial resistance (AMR) by the cascading scale of its consequences, from a resistant microbe to a missed harvest to food that isn’t on the table. His practical entry point was formulation: years of developing crop inputs and realising that most agricultural antimicrobial design has no AMR thinking built in. He chose SAAFE because it was the only program he had found that funds work across agriculture, food, environment and human health, with industry in the room the whole way through.

Barcley’s long-term goal is to develop a coating that can replace or reduce reliance on conventional crop antimicrobials backed by the dose-response data, rain-fast formulation and real-world evidence that will mean it’s accessible to farmers, not just published in a scientific journal.