DISEASE

NAME
Rose Canker
Coniothyrium fuckelii


Description
This is a fungal problem involving a weak fungus that enters the plant through wounds causing dieback.

Symptoms
The stems become discoloured (pale brown) usually from a pruned point, working its way down the stem and normally forming an angular intersection with live cambium. The bark splits or cracks and infected areas can develop tiny black fruiting bodies. Heavy infected plants eventually die, though certain varieties are resistant halting the spread of the infection.

     

Source and Dispersal
The spores are found on infected dead plant material and can be dispersed by wind and splashing water.

Favoured Conditions
It prefers a warm humid conditions and plants that have a wounds derived from poor pruning techniques and insect or other damage, especially if water is allowed to settle on the wound.
     
Affected Plants
It specifically attacks rosed with some varieties more susceptible than others.



Non-chemical Control
Correct pruning techniques with sharp secateurs well below the infected areas. Ensure that there are no ragged edges, the angle of the cut allows water to run off and it is the correct distance from a bud.

Chemical Control
There is no satisfactory chemical control and prevention is imperative.