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majority of viruses are spread
by pests. It is therefore very
stance on and under the
leaves, rotten patches or spots important to control pests on
on the leaves, fruits and stems vegetables.
and wilting caused by root
Your local nursery will be able
rot.
to sell you a number of sprays
and powders to counteract
Bacteria are microscopic
the various diseases. Take
single-celled organisms
care to follow the instructions
producing diseases that take
carefully and be sure that you
on many forms. Most
wait the required length of
bacterial diseases attack the
vascular system of the plants. time before harvesting the
When a plant is infected by a produce for consumption.
bacterial disease the whole
However, chemical solutions
plant and the plant residues
to the problem often have
must be removed carefully,
collateral damage. Poisonous
including the roots, and then sprays or powders are
destroyed.
indiscriminate and often kill
beneficial wild life such as
Viruses are infectious agents
that are so tiny that
infections are only
identified by the
symptoms they
produce on the
plant. Common
symptoms are
mottling, stunting,
crinkling and other
distortions of
foliage. The
Powdery mildew
IN THE GARDEN
bees, birds or bats.
So you might prefer to
develop a programme of
spraying with ingredients that
are less toxic to the general
environment. The following
can be used in rotation.
Bicarbonate of soda is nontoxic, readily available and
inexpensive. It can be
effective against powdery
mildew and somewhat useful
against black spot. Add one
tablespoon of bicarbonate of
41
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soda to three litres of water.
When the bicarb has
dissolved, add ¼ to ½
teaspoon of dishwashing
liquid. Shake well. The
dishwashing liquid acts as a
wetting agent, ensuring the
bicarb spray sticks to the
plant. You can also buy
proprietary liquid wetting
agent at your local garden
store.
Be aware though that if you
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