no account should infected plants be used for future propagation and
all infected stools should be destroyed. Because the soil will
contain bacteria which can survive long periods on small pieces of
plant tissue the area should not be used again without sterilisation.
bacterium carries a plasmid which switches genes on for the tumour
production and this acts in a similar way to a virus but it is not a
virus. This disease is used in recombinant DNA technology.
Impact/effects on chrysanthemums
Basal area of chrysanthemum stool where irregular growths are formed
on the stool (usually below soil level). The main qualitative implications
from this disease relate to future propagations from the infected
stock and to perpetuating the disease by constantly cropping from the
There is no chemical cure for this disease.
Some actions that can be taken to
minimise disease impact include:
- Drainage should be improved to reduce the survival of the bacterium
in the soil.
- Inspect new stock to avoid
contamination of the soil. Where the disease is present, a crop of
potatoes or other vegetable (except beet) may help to eliminate the
- Wounding should be avoided,
particularly root wounding during planting