PubMed · 2026-04-28
Scientists developed a fast, cheap genetic test to detect fungicide-resistant strains of gray mold (Botrytis cinerea) and confirmed that the resistant mutations carry no fitness penalty, meaning resistant strains spread just as aggressively as susceptible ones.
Among 82 resistant Botrytis cinerea isolates from strawberry and tomato, 70.2% carried the L412F mutation, 8.3% the L412V mutation, and 4.7% the G408V mutation in the Bcpos5 gene.
CRISPR/Cas9-generated mutants carrying L412F and L412V showed no significant fitness costs — their mycelial growth, spore production, and plant infection ability matched the non-resistant reference strain.
A new T-ARMS-PCR test can rapidly and cheaply identify the three most common resistance mutations from a single DNA sample, validated against Sanger sequencing across 170 field isolates.
