36th International Carrot Conference Abstract

Carrot Trimming Technology for Control of White Mould

H. Roberts, M.R. McDonald and D. Van Dyk.

Department of Plant Agriculture, University of Guelph, Kettleby, ON, L7B 0E9. Email: hrober01@uoguelph.ca, phone: 905-775-3783

White mould of carrots is caused by the fungal pathogen Sclerotinia sclerotiorum which is commonly found in commercial carrot fields. Initial infection begins in the field, however severe losses can occur in storage. As the carrot canopy closes, sunlight and airflow are reduced. This increases humidity and prolongs leaf wetness, creating ideal conditions for sclerotinia growth. Previous research has shown that canopy trimming can significantly reduce sclerotinia infection by minimizing these conducive environmental conditions. In 2009, a project was initiated to develop an adjustable tractor mounted carrot trimmer for the Bradford/Holland Marsh, Ontario, to test and demonstrate the efficacy of trimming technology to reduce white mould infection.

Five commercial field sites in the Bradford/Holland Marsh were used for carrot trimming trials, two in 2010 and three in 2011. Disease pressure was low in both years and only one site had significant difference in disease between treatments. Storage assessments were performed on carrots harvested from two field sites and no differences were found between trimmed and untrimmed carrots. From 2010 to 2012, trials using canopy trimming alone and in combination with fungicides Lance, Elexa-4 (2010 and 2011) and Allegro (2012) were conducted at the Muck Crop Research Station in the Bradford/Holland Marsh Ontario. Trimming significantly reduced infection at one site. In all trials carrot trimming did not have a significant effect on marketable yield among treatments. The adjustable carrot trimmer built for this project is now available for growers in the Bradford/Holland Marsh to test the efficacy of canopy trimming.

Last updated Thursday, 25-Jul-2013 11:51:50 CDT