If growers cannot identify the cause
of disease, they may be able to consult specialists in the field, submit
samples to plant disease clinics or
local citizen science projects, or participate in public training workshops. Starting in 2016, a citizen
science initiative will invite growers
to submit samples for identification
of Phytophthora species. Phytophthora is a group of microorganisms responsible for many plant
diseases in South Africa (e.g. late
potato blight and various root rots
in avocados, eucalyptus, and proteas). Cape Citizen Science is a project
designed to survey Phytophthora
species throughout the Western
Cape with specific emphasis on the
fynbos biome. The project invites
members of the public to report
dying plants, submit samples, and
participate in the research in a variety of other ways. The project will
also organize several workshops
throughout the Western Cape to
train participants how to recognize
disease and isolate the responsible
organisms. Contact information
and more information about the
project can be found at: http://
citsci.co.za.
Once a pathogen has been identified or is strongly suspected, control strategies can be implemented
to contain or eradicate the organ-
Mycelial fan at root collar
ism and prevent further impacts.
For example, if a Phytophthora species is suspected to be causing root
rot in one field, it may be beneficial
to avoid transporting soil from that
field to other fields by washing machinery. In another example, if potting material is infected, it may be
necessary to compost, fumigate, or
solarize the material before reuse.
Lastly, some pathogens may be present in the water sources used for
irrigation. This may affect certain
plant species and not others. Many
pathogens are specialists, only infecting certain hosts, but some
pathogens are generalists, infecting
multiple species. Generalist pathogens may be more frequently confused with abiotic disturbances
such as drought. Phytophthora cinnamomi is an example of a generalist pathogen, causing root rot or
damp