Rhizoctonia Belly Rot of Cucumbers Elaine Roddy Vegetable Crops Specialist OMAF/MRA

Symptoms on the belly or tip

Further colonized by fruit fly larvae

Rhizoctonia Solani (Kuhn anamorph) Strain: AG 4 known to infect cucumbers Temperature Range: F Optimum Temperature: 80 F High Humidity or Following Heavy Rainfall – Monday & Tuesdays have the highest levels Survives as dormant mycelium or sclerotia in infested crop debris

Pathogenicity C. Trueman, University of Guelph – Ridgetown Strains AG2-2 IIB and AG2-2 IV are commonly found in Southwestern Ontario (Sugarbeet study) Isolates belonging to all three groups were pathogenic to inoculated cucumber fruit (lab) Study used greenhouse “mini” cucumbers (persian).

Future Directions Soil Applied Fungicides = Very Inconsistent Pathogenicity in field conditions – Pickling cucumber varieties Hosts – Weeds – Rotational Crops Agronomic Practices – Tillage, irrigation, rotation, soil types…..