Field Guide of Discovery-based Exercises for - Aseanipm ...

Exercise No. 5.02 176
SIMULATION EXERCISE: UNDERSTANDING DISEASE
TRANSPORT IN ORGANICALLY-GROWN VEGETABLES
BaCKGroUND aND raTIoNalE
Plant pathogens are very minute disease-causing
microorganisms that reduce the aesthetic value, quality,
and yield of infected organic vegetable crops. Unlike insect
pests, which normally moves using their appendages (e.g.,
wings, legs, etc.), microorganisms are transported mainly
through mechanical means from one place to another.
Thus, disease transport can be accomplished by any of the
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Field Guide of Discovery-based Exercises for Organic Vegetable Production
following means: (a) carried from source by wind or water, (b) transported from source by clinging
to anything it came in contact with, or (c) transferred by man and animals directly from source to
another point either intentionally or accidentally.
Clearly, diseases do not just occur. They consist of a sequence of various stages during the course
of their development, a succession of events or modifications, one usually leading to another. These
living and non-living things play an important role in the dissemination of diseases. However, these
agents have their own way of transporting a disease 177 .
In farmer field schools (FFSs), farmers can better understand mechanisms of disease transport
through field walks, observations, simulation exercise and participatory sharing of experiences
among them and facilitators. This exercise was developed to serve this purpose.
How long will the exercise take?
when is this exercise most
appropriate?
ɶ During FFS, TOT,
and VST sessions as
component of ‘Integrated
Disease Management’
topic; and
ɶ When farmers want
to learn how organic
vegetable diseases are
transported from one
place to another.
• Thirty minutes to one hour field walk observation and simulation exercise; and
• Thirty minutes to one hour brainstorming session.
176 Adapted from Callo, Jr., D.P., L.B. Teofilo, and H.A. Tauli (eds). 2002. Field Guide of Discovery-based Exercises for Vegetable IPM, Volume II. SEAMEO
Regional Center for Graduate Study and Research in Agriculture (SEARCA), Los Baños, Laguna, Philippines. pp218-220.
177 IIBC. 1996. Integrated Pest Management for Highland Vegetables, Volume 4: Training Guide for Participatory Action Towards Discovery Learning.
International Institute for Biological Control, BPI Compound, Baguio City, Philippines. pp113.