By Josie Borlongan, Garden Guides Contributor Various bacteria may
cause leaf spots. The common causing pathogens are Pseudomonas and
Xanthomonas. Bacterial spots are usually spread by rain or watering
splash from leaf to leaf or sometimes from stem lesion to
leaves.
Prevention and Control
To prevent or control the spread of bacterial spot, promptly remove
the infected leaves. Young planting may be uprooted and thrown in
the compost pile. Avoiding use of overhead irrigation may also help
in the prevention and control.
Affected Plants
Bacterial spots can be seen in assorted plants, with some more
susceptible than others.
Damage
Bacterial spots can cause necrotic patches usually angular in the
outline of the leaves. They are also characterized by a bright
yellow halo.
Natural Insecticides
Copper is a natural mineral that can be applied as dust or foliar
spray. It is the strongest type of organic bactericide and
fungicide available. Apply copper sprays when there is a high risk
of bacterial spots that are starting to develop. Repeat every 7 to
10 days and respray if the rain washes it off.
Other Methods of Control
* Garden Cleanup: Remove infected leaves and plantings. Discard any
noticeably diseased materials.
* Crop Rotation: Rotate crops every 2 years.
* Clean Tools: Avoid using tools on healthy plants that were used
on infected plants. Sterilize tools in warm water or by rubbing
disinfectant before using.
* Soil Solarizing: Heat can be very effective in killing bacterial
spores that may be present in soil and compost.
