Temporal development and relationship amongst brown rot blossom blight, fruit blight and fruit rot in integrated and organic sour cherry orchards

摘要

The aim of this 4-year study was to characterize temporal development of brown rot blossom blight and fruit blight (caused by Monilinia spp.) and their sporulating areas in sour cherry orchards; and to determine the relationships amongst incidence and sporulating area of blossom blight, fruit blight and fruit rot. The study was performed in integrated and organic orchard blocks on two cultivars (Ujfehertoi fiirtos and Erdi botermo). On both cultivars, disease progress on flowers and fruits was 2-10 times slower in the integrated than in the organic management system. The peak incidence values were 9 and 31 days after petal fall for blossom blight and fruit blight, respectively. After these dates, no new blight symptoms on flowers and/or fruits appeared and the disease was levelling off. Final blossom blight incidence ranged from 1 to 5% and from 12 to 34%, and fruit rot incidence from 2 to 6% and from 11 to 26% in the integrated and the organic orchards, respectively. The sum of fruit blight incidence ranged from 9 to 22% for the organic system, but was below 5% for the integrated system, while the final sporulating area was 5-16 mm~2 and <3 mm~2, respectively. Among the five highest Pearson's correlation coefficients, relationships between blossom blight and early fruit blight stage (r = 0-845, P = 0-0087 integrated; r = 0-901, P = 0-0015 organic), and between sporulating area and fruit rot (r = 0791, P = 0-0199 integrated; r = 0-874, P = 0-0039 organic) were the most significant relationships from an epidemic standpoint as they indicated a connection between different brown rot symptom types.