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

Section 5 • Integrated Disease Management
learning objectives
• To make participants aware and understand how accurate virus disease identification and
transmission lead to its better management in their own farms; and
• To learn through hands-on and direct observations how virus diseases are transmitted in
organically-grown vegetables by mechanical means.
materials
• Organic vegetable fields where signs and symptoms of virus infections can be observed;
• Mortar and pestle (can be improvised), suspected virus infected and healthy test-plants, handsprayer
and sandpaper); and
• Other office supplies (e.g., Manila papers, notebooks, ball pens, and marking pens).
methodology
• Field walks, hands-on and brainstorming
steps
1. Divide participants in small groups and ask them to conduct field walks. Let them observe
and collect healthy and suspected virus infected plants or plant parts in learning and adjoining
organic vegetable fields. Interview other farmers, if necessary. List down all observations
related to signs and symptoms (e.g., rosetting, curling, mosaic appearance, etc.), pest and
disease occurrence, kind of crops planted, crop stand, etc.
2. Go back to processing area and set-up this exercise by performing the following activities:
5 Pound suspected virus-infected plants and extract juice or sap;
5 Create artificial mechanical damage by rubbing sandpaper on leaves of healthy test-plants
(e.g., same crop species, or any seedlings of other crop species);
5 Spray or rub extracted sap or juice on damaged and undamaged leaves of healthy testplants;
and
5 Observe and take note of physical changes on test-plants after 14-21 days.
3. Brainstorm in small groups and present output to the big group. Conduct participatory
discussions to allow sharing of experiences among participants and facilitators.
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