FACTSHEETS FOR FARMERS
www.plantwise.org
Created in
Kenya
,
December
2012
Bacterial Soft Rot on Brassica
Recognize the problem
Soft rot is a disease among brassicas causing them to turn soft and rot with a
bad smell. It is also known as bacterial soft rot or bacterial root rot. Soft rot is
often a problem after harvest but affects the cabbage and Chinese cabbage in
the field. On turnip and rutabaga the disease may be found in the field but is
most severe during storage.
The infected heads are watery and often have a complete head rot. The
affected area becomes soft and mushy and turns dark in colour. Eventually the
bacteria, which cause the rot, decay the entire plant.
Background
The infection occurs on leaf stock which is in contact with the soil, and then
moves to the head. The bacterium is spread by water splashes or contaminated
tools such as hoes or knives. It also spreads in waterlogged soils and
contaminated water. Warm and moist conditions favour the development of the
disease. When other diseases such as black rot and damping off damage the
crop, it is easier for soft rot to get into the crop.
Management
Non-chemical control
•
Hands and tools should be washed and disinfected regularly during and
after harvesting.
•
Harvesting should not be done in warm and moist conditions.
•
Frequent irrigation during head formation should be avoided to allow
heads to dry.
•
Prevent other diseases like black rot and damping off.
•
Planting on ridges, raised beds or well drained soils prevents water
logging around the plants.
•
Harvest healthy heads early when heads are tight and put in crates that
are washed thoroughly and disinfected.
•
Crop rotation should be practiced and the use of clean water should be
practiced.
No chemical control measures are recommended.
Scientific name(s)
>
Pectobacterium carotovorum
subsp.
carotovorum
The recommendations in this factsheet are relevant to
:
many countries where this pest or problem is present
Authors
:
This factsheet is based on information written for "The Brassica Farming
Handbook", first published by KENGAP Horticulture 2011.
Kengap Horticulture Ltd, P.O Box 12898-00400 Nairobi, Kenya
tel:
+254 722 575544; +254 723 491549
email:
books@kengap.co.ke;
www.kengap.co.ke
Edited by
Plantwise
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042En
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Bacterial soft rot on cabbage.
(Photo by Kengap Horticulture)