Disease Transmission and Fungicide Control of Anthracnose in Dry Bean
Colletotrichum lindemuthianum (Sacc.& Magn.) Briosi & Cav. is an important pathogen in the Canadian dry bean (Phaseolus vulgaris L.) industry. It has been purported that transmission of the pathogen can occur from machinery and clothing, but there was little scientific evidence of this. Field trials determined that transmission of C. lindemuthianum occurred from leather, metal, denim and rubber materials using artificial and natural inoculum sources. Material type was usually not significant, but canopy moisture increased disease severity, particularly with a natural inoculum. Foliar fungicides are a common means of controlling C. lindemuthianum. Separate field trials were conducted to evaluate the efficacy of fungicides on their own, and in conjunction with disease transmission by materials. Simultaneous application of fungicides did not negate disease transmission by materials. Strobilurin fungicides and thiophanate-methyl were most effective at controlling anthracnose symptoms. In conclusion, sanitization procedures should be considered for equipment and workers clothing particularly for producers of pedigreed seed and custom equipment operators.