FUNGICIDE APPLICATION ACCORDING TO INFECTION PERIODS, A MUST FOR INTEGRATED SCAB CONTROL ?

Since 1976 apple scab has been successfully controlled by fungicides applied according to infection periods in experimental plots and also in a steadily increasing number of commercial orchards.
To guarantee adequate preventive and curative action at the same time captanoid fungicides (e.g.
Capan, Folpet, Dichlofluanid) were applied in combination with compounds having a curative activity.
In the seventies benzimidazol-fungicides were used as the curative component and after 1980 they were gradually replaced by sterol-biosynthesis-inhibiting fungicides (SBI).

To prevent storage diseases (mainly Gloeosporium species and storage scab) two sprays of captan are essential in late summer.
Using captanoid fungicides is also part of the strategy to prevent buildup of resistance of Venturia inaequalis against SBI. Monitoring scab-resistance to SBI is of utmost importance since the control according to infection period depends entirely on their excellent curative action.

Symposium on Integrated Fruit Production

H. Schüepp, E. Bosshard, W. Siegfried

https://doi.org/10.17660/ActaHortic.1990.285.23