VIEW ARTICLE

Ecology and Epidemiology

Influence of Temperature and Wetness Duration on Infection of Peach and Sweet Cherry Fruits by Monilinia fructicola. A. R. Biggs, Research scientist, Agriculture Canada, Research Station, Vineland Station, Ontario, Canada, L0R 2E0; J. Northover, Research scientist, Agriculture Canada, Research Station, Vineland Station, Ontario, Canada L0R 2E0. Phytopathology 78:1352-1356. Accepted for publication 16 May 1988. Copyright 1988 Department of Agriculture. Government of Canada. DOI: 10.1094/Phyto-78-1352.

Nonwounded peach and sweet cherry fruits were inoculated with a conidial suspension of Monilinia fructicola at temperatures of 15–30 C at 2.5 C intervals, and wetness durations of 3–15 hr (peach) or 6–18 hr (cherry) at 3-hr intervals. Both peach and sweet cherry had an increased incidence of fruit infection with increased wetness duration over the range of temperatures tested. Optimum observed temperature for cherry fruit infection was 20–22.5 C. with greater than 80% infection after 15 hr of wetness. After 18 hr of wetness, infection was greater than 80% at all temperatures except 30 C. Optimum observed temperature for infection of peach fruit was 22.5–25 C. Greater than 70% infection occurred after 12 hr at all temperatures except 27.5 and 30 C. Nontransformed polynomial and logistic equations for peach and cherry, respectively, were chosen as the best regression models to describe the incidence of fruit infections as functions of temperature and wetness duration. Coefficients of determination for two sweet cherry and two peach experiments were 0.89 and 0.90, and 0.71 and 0.84, respectively. The Analytis “Beta” model was used to describe the effect of wetness duration on incubation period for sweet cherry. The incubation period decreased with increasing wetness duration. All models had significant coefficients, and the experimental runs were similar within fruit species.