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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.