parasitic pathogens
Even plants cocooned in the well-protected environment
of an indoor garden are susceptible to the forces of evil
called parasitic pathogens from time to time. We may not
be able to completely exclude their presence, but there
are many weapons in the battle against these plagues, and
all that’s needed is the knowledge of how to use them.
Parasitic or infectious diseases are those caused by a living
enemy—a pathogen that may be a fungus, bacterium or
virus. On the other hand, non-parasitic or non-infectious
diseases are caused by non-living agents such as nutrient
deficiencies, cold, heat, toxins, pollutants, salts, drought,
mechanical injury and physiological disorders, including
tip burn and blossom-end rot. But just to compound the
problem, many non-infectious disease problems can look
remarkably like a pathogen problem, leaving growers
fighting an enemy that doesn’t exist and not tackling the
real cause of the problem.
Pathogenic or Parasitic Diseases
Viral diseases can cause strange, twisted and deformed growth.
Just as we can’t see the pathogens that bring on our
dreaded colds each winter, plant diseases are just as good
at avoiding detection. Plant pathogens are all around us:
fungal spores are common in wind-blown dust, on soil, in
water, on clothing, hands and equipment, not to mention
on incoming plant material and even seeds. Fungi, bacteria and viruses can even be carried by insect pests and
injected directly into plant tissues during feeding. While
it’s virtually impossible to exclude these from a growing
environment, parasitic diseases require three essential
factors before they infect plants: a susceptible host plant,
a live parasitic agent and an environment favorable to
disease development. This is known as the disease triangle.
The key to preventing outbreaks in an indoor garden or
greenhouse is to eliminate one of these factors and the
problem is averted before it’s even begun.
Pythium root rot is one of the most dreaded of all the parasitic pathogens.
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Maximum Yield USA | April 2015