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

Section 4 • Integrated Insect and Rodent Pests Management
5 Label Oslo paper with time and date of parasitization;
5 Let egg strips dry for several minutes then expose them to emerging Trichogramma sp
inside cellophane parastization container; one strip Trichogramma sp egg parasitoid is
enough to parasitize 2 fresh egg strips or 1:2 ratio;
5 Blow air inside cellophane and close it tightly with a rubber band;
5 Place it inside plastic trays with holder for free ants and other insects; Corcyra eggs
should be parasitized on third or fourth day; eggs turn black upon parasitization
5 Small and big group participatory discussion and interactions will follow thereafter.
C. storing and stocking:
5 Store collected Corcyra eggs up to 10 days in refrigerator at 10 o C; and
5 On 6 th day of parasitization, store parasitized Corcyra eggs or Trichogramma sp
parasitoids up to 14 days at 10 o C.
Using Trichogramma sp. as Egg Parasitoid:
Inundative release, which is the colonization of large number of natural enemies to inflict
prompt mortality on pest population, is implemented. This is done because parasitoid
releases are usually alternated with chemical insecticides, which seriously affect parasitoid
survival.
stage of Parasitoid, Time, and Frequency of Field releases:
Trichogramma sp. can be released in vegetable field as pupae (about to emerge) or as
emerging adults. Pupae are released late in afternoon while adults should be released
early in the morning. In case of tomato, release of Trichogramma sp may be started during
appearance of first flower buds or 35 days after emergence (DAE) or when field surveys
show high number of lepidopterous eggs. This is done at least once a week until 75 days
after planting (DAP), depending on severity of infestation. The first and second releases
should be closer with 3 days interval. Succeeding releases can be done on a weekly basis.
manner and site of Parasite release:
Trichogramma sp. in strip is released by inserting it in cut leaf petiole in upper portion of
canopy of plant. The release stations should be situated at least 5-10 m from border of crop
field. The inner release stations should be spaced 15 to 20 m in between.
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