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END OF PROJECT REPORT
NN-001-2008
Evaluation of Proprietary Formulations of Insect Repellent Containing
EGX-101 and Testing Mosquito Larvicide products Based on Trypsin
Modulating Oostatic Factor (TMOF) Against Dengue Vectors
PROJECT LEADER: PROF DR SALLEHUDIN BIN SULAIMAN
PROJECT TEAM MEMBERS: PROF MADYA DR HIDAYATULFATHI OTHMAN
NORASHIQIN BINTI MISNI
MOHD SAIFUL AZLAN BIN NORDIN
LAU MING SEONG
SITI FATIMAH JOHARRY
Project Duration: 24 (months)
Project Start Date: November (month) 2008 (year)
Project End Date: November (month) 2010 (year)
Collaberations:
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OUTDOOR EVALUATION OF TMOF-BTI IN VARIOUS FORMULATIONS AGAINST
FIRST INSTAR OF Aedes aegypti Linnaeus IN THE AREA OF UKM CAMPUS
By Saiful Azlan Bin Nordin, Biomedical Sciences, FSKB, UKM
Supervised by Prof. Dr. Sallehudin Sulaiman & PM. Dr. Hidayatulfathi Othman
5th November 2010
INTRODUCTION
Combination of TMOF-Bti in rice husk and wettable powder formulations in
various weights were used in this trial in order to test the efficiency of these
combinations against first instar Aedes aegypti larvae in outdoor area. The objective of
this study was to evaluate the efficiency of TMOF-Bti formulations in various weights in
simulated field conditions at UKM campus.
METHODOLOGY
Simulated Trial in the Area of UKM Campus
Materials used in this trial were buckets and mosquito netting. Combination of
TMOF-Bti in rice husk formulation (2% TMOF + 2% Bti; 4% TMOF + 4% Bti) and
wettable powder formulation were produced by EntogeneX Industries Sdn. Bhd. The
larval food was crushed dry leaf powder where the leaves were collected from areas
around campus UKM. Aedes aegypti larvae used in this trial were reared in insectarium
of the Faculty of Allied Health Sciences, UKM. 20 first instar Aedes aegypti larvae were
placed in a plastic bucket containing 4 liters of water. TMOF-Bti combination in rice husk
formulation with the following weights viz: 50 mg, 100 mg, 150 mg and 200 mg
respectively was each distributed in 4 liters of water in each bucket; while TMOF-Bti in
wettable powder formulation were measured in the following weights viz: 2mg, 5 mg, 10
mg and 20 mg respectively and each concentration was placed in each bucket.. Each
concentration runs as duplicates. Crushed dry leaf powders were supplied as source of
food for the larvae. All buckets were covered by mosquito netting. Larval mortality was
recorded after 24 hours and weekly. A new batch of 20 1st instar larvae Aedes aegypti
was introduced into the buckets weekly without additional TMOF-Bti formulations
added..
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RESULTS
Simulated trial in the area of UKM campus
Simulated trial had been carried out in the area of UKM campus. These trials were
carried out in different locations. The area where the study was carried out were at
outside of workers’ resting room in UKM, 2nd floor of Block C and 2nd floor of Block B in
UKM.
TMOF- Bti WETTABLE POWDER 20+20
Figure 1 : Mean of Larval survival percentage after the exposure to TMOF-Bti
in wettable powder formulation From 18th August 2010.
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TMOF- Bti RICE HUSK FORMULATION 2+2
Figure 2 : Mean of Larval survival percentage after the exposure to TMOF-Bti
in rice husk formulation in various weights (Rice Husk Formulation 2+2 )
from 18th August 2010
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TMOF- Bti RICE HUSK FORMULATION 4+4
Figure 2 : Mean of Larval survival percentage after the exposure to TMOF-Bti
in rice husk formulation in various weights (Rice Husk Formulation 4+4).
DISCUSSION
From the graphs of figure 1 until 3,we can see that there are similarity between all these
formulations, 0% of larval survival were recorded for the first two weeks of the study
being carried out except for 10mg of rice husk formulation 4+4. This shows that these
formulations were very effective on the first 2 weeks of application for killing the 1st
instar Aedes aegypti larvae.
From week 3 onward, the graph of larval survival shows increasing of larval survival.
The percentage survival increased until the 5th week but still there were larvae killed by
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all the formulations and the maximum percentage for the larval survival was 50%.Thus
the three formulations of TMOF-Bti could retain their efficacy for 5 weeks. The reason
for this to occur could probably due to the effect of TMOF giving the larvicidal effect in
long term duration. TMOF causes larvae to starve and thereby slow down the larval
development process, and finally lead to death. Bacillus thuringiensis israelensis (Bti) is
short-lived in field conditions (Zaritsky et al. 2008). The results showed the same trend
as the trial continued for weeks 3, 4 and 5 respectively. Larval mortalities in control sets
basically were low from the first week till week 4. However, in week 5, there was a
sudden decreased in the numbers of larvae survived in the control buckets, most
probably due to insufficient food. Changing of water environment in the buckets might
affect the larval survivorship as well.
CONCLUSION
TMOF-Bti in both rice husk and wettable powder formulations had proven to be effective
against first instar larvae of Aedes aegypti. Thus,it could be another potential control
agent for dengue vectors.