A survey of 54 commercial lowbush blueberry fields in Nova Scotia in 1998 showed that the incidence of stems infected with red leaf disease, caused byExobasidium vaccinii, had a median of 2.6, a mean of 3.6, and a maximum of 15.3. Age, origin (from old pasture fields or woodlands), pruning history (burn or mow) of the field and geographic region within the province were considered as covariates for explaining the differences in disease incidence among fields. Age of the field was the only significant covariate with an average increase in disease incidence of 0.1 per year. Red leaf reduced the number of flowers by 42 and the number of berries per stem by 74. The proportional loss in total yield in any field roughly equalled the disease incidence. The baseline data obtained in this survey will be useful for monitoring incidence of this disease in the future.
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