1. MARILYN M. BALAIS
LEIRA JIM V. TANGIAN
MYRTLE ANNE FAYE N. VIRATA
ENTOMOPATHOGENIC NEMATODES
AGAINST Ostrinia furnacalis
(ASIAN CORN BORER)

2. INTRODUCTION

3. Background of the Study
Insects play important parts in the
ecosystem
Entomopathogenic nematodes (EPNs)
as biopesticide to control the Corn
borers
Achroia grisella (Lesser Wax Moth) as
alternative EPN bait

4. About A. Grisella (lesser wax moth)
Wax moth is a serious pest in
beehives and can cause
substantial losses of
combs, damage to beehive
material and spoil beehive
products.
10 to 13 mm long

5. Larval stage

6. GROUP OF NEMATODES!!!
THE GOOD THE BAD THE UGLY
Entomopathogenic nematodes (EPN

7. Entomopathogenic nematodes

8. Entomopathogenic nematodes

9. Ecological indicators/Pollution
studies
Species Interaction studies
Biological Control Agents
Genetics studies
Molecular studies

10. Why BIOLOGICAL CONTROL
Agents?
NO TO EXTENSIVE
SYNTHETHIC
CHEMICAL
APPLICATION

12.  Entomopathogenic Nematodes (EPNs) in the genera Heterorhabditis
and Steinernema are used as biological control agent (BCA) for diverse
insect pests.
Family : Steinernematidae with 45
known Steinernema sp.
Family : Heterorhabditidae with 11
known Heterorhabditis sp.
The enemy of my enemy is my friend
THE AMBUSHERS THE CRUISERS
EPN pest

13. Objectives of the Study
The study aims to apply isolated EPNs from
soil samples from PSHS – CMC grounds
against the Asian Corn Borer (Ostrinia
furnacalis).
Specifically, the study aims to:
1. extract the EPNs present from the wax moth
larva;
2. identify the EPNs up to its species level;

14. Objectives of the Study
3. apply the extracted EPNs to the larva of the corn
borer;
4. note the mortality rate and qualitative
morphology descriptions of the effects of the
EPNs on the Asian Corn Borer larvae;

15. Significance of the Study
EPNs as biopesticide and growth control
of insects
Cheap and easy way to obtain EPNs
Introduces a new and environmental –
friendly way to eliminate plant pests

16. Life-cycle of EPNs in vivo and in vitro
Culturing of
EPNs

17. In the PHILIPPINES?
Recent studies are undergone in MSU-IIT
and now in PSHS-CMC

18. Corn borers are one of the major pests in
the corn production industry.
Eliminating pests from corn can make a
great impact in the Philippine agriculture

19. Scope and Limitations of the Study
Usage of the lesser wax worms as bait for
the EPNs from the soil sample
Pathogenicity test in the laboratory is
limited to the counting of the number of
dead Asian Corn Borer larvae, as well as
on noting on the qualitative effects of the
EPNs on the external morphology of the

20. Scope and Limitations of the Study
Only one site is selected within the
PSHS-CMC campus
Collected EPNs will be used
against the larvae of the corn borer
in the laboratory

21. MATERIALS AND METHODS

22. Materials and Methods Flow Chart
Wax Worms
Subculture
Pathogenicity
Test on Corn
Borers
Nematode
Subculture
Collection of
Soil Samples
Quartering
Method
Nematode
Baiting
Artificial
Media
Preparation
Analysis of
Data

23. How to obtain Dauer Juveniles
from the Soil?

24. Ten-points Plotting
Ten points represented by circle with 1
meter distance in each point will be
made in the sampling area

25. Quartering Method

26. Nematode Baiting
 After soil collection from different areas, collect
subsamples and place in a small cup (100g soil only)
 Put at least 5 larval stage of A. grisella inside the
cup, cover using the lid and put the sample under
room temperature.
 After 24 hours, examine the larvae in the soil, if
morbid leave for another 24 hrs and if found dead
after 3-7 days depending on the species, collect the
cadaver
 Rinse the cadaver using either distilled water
 Transfer the cadaver to white trap

27. White Trap

28. Subculture of EPNs in
RINGER's solution
Apply
subcultured
EPNs
against the
Corn Borers

29. Application of the Isolated EPNs
against Corn Borer
 last stage of the corn borer larva was used and small
plastic cups with filter paper were each filled with one
larva
 (1 larva/concentration times 3 replicates) times 3 trials
 nematodes were counted by putting small drops of
the solution on the Petri dish and then the droplets
were examined under the spectroscope
 add drop/s with 5, 10, 20, 30, 40, 50 EPNs) on each
borer
 filter paper in the cup is moistened

30. 24-well plate
 The same
procedure will
be done for the
lesser wax

31. Gathering of
Data
 checked after 12, 24, 36, 48 and 72
hours to see if the corn borers were
dead
 Death of larva is caused by successful
invasion of EPNs if the cadaver shows
discoloration and presence of EPNs
when dissected
 Note on the mortality rate per

32. Analysis of Data
 Corn Borer as bait
 The t-test computed the permutation t-test
p-value
 t-test had been acquired using (PAST)
software
 Pathogenicity Test
 Probit analysis
 Abbot formula

33. Results and Discussion
 Corn Borer as bait
 cadavers of the corn borer larva cup were then collected
and recorded on the 3rd, 5th, and 7th day of the baiting
procedure
 Discoloration
 Heterorhabditis group
 no significant differences between the permutation t-test
values since the results were more than 0.05
 Pathogenicity test
 LC50 of the pathogenicity test, derived by probit analysis
 44% control mortality

34. Figure 1. Photo of EPNs seen under the
dissecting microscope (magnification 40X)
(taken on September 15, 2012, MSU - IIT).

35. Results and Discussion
 Pathogenicity test
 Abbot’s formula
 n = Insect population, T = treated, Co = control
 Other observations

36. Conclusions and Recommendations
 corn borer larva can be used as an alternative
EPN bait
 corn borers are effective bait for Heterorhadbitis
group
 40 concentration/larva is best effective since it
has the highest percent mortality from the LC50 as
well as in the Abbot mortality after 12 and 72
hours
 suggest that the set-up should be monitored
regularly and new insect larva may be applied
with the nematodes
 recommended that there will more specific and

37. Thank you for listening!
We are now ready for your
questions.