Development of effective control strategies for Rosellinia root rot on pome fruit

The general observation from role players in the deciduous fruit industry is that Rosellinia white root rot of apples is not a major problem in apple orchards.  However, it is important to ensure that plant samples with root rot problems be diagnosed for both Phytophthora and Rosellinia infections. Diagnosis of Rosellinia should include incubation of infected plant material in a moist chamber, which is the only reliable way of ensuring the formation of white mycelial sheets, important for the initial identification and isolation of the pathogen.

Spot fumigation of infested soil or to remove soil from plant holes and then either to fumigate or replace it with clean non-orchard soil seems to provide a promising control strategy for the disease.  Supplementing these practices with plant/root growth promoters and biocontrol agents could potentially increase the survival/recovery rate of established and replanted trees.

An information pamphlet dealing with symptoms, diagnosis, biology and management of Rosellinia white root rot has been compiled and issued by ARC Infruitec-Nietvoorbij.