Larvicidal activity of Melaleuca leucadendra leaves extract against Aedes aegypti.

Dengue Hemorrhagic Fever (DHF) depends on controlling Aedes aegypti mosquitoes and larvae. Currently, larvicide control still uses temefos larvicide, though several studies have reported resistance. Insecticides from plants can be used as an alternative. One of the plants reported to have larvicide potency was Melaleuca leucadendra leaves. This study aimed to look at ethanol extract of M. leucadendra leaves activity in killing A. aegypti larvae and LC50 values after a 24-h examination. This type of research was experimental design with post-test only control group design. M. leucadendra leaves was extracted through maceration process using 96% ethanol. The treatments consisted of 8 concentrations (mg L-1) of 400 (0.04%); 1000 (0.1%); 1600 (0.16%); 2000 (0.2%); 10,000 (1%); 20,000 (2%); 30,000 (3%); 40,000 (4%) and the control group (0%). Each concentration was replicated four times and applied on twenty specimens of A. aegypti at the third larval stage. The results showed that M.leucadendra has a lethal ability against A. aegypti. There was a correlation between the extract concentration and the larval mortality (p = 0.000; 95%). The extract concentrations of 0.04-0.2% caused <3% mortality, while the highest mortality (47.5%) achieved at the conc. of 4%. The LOGIT test showed that the number of LC50 was 3.7% (37,600 mg L-1) with 95% significance. A high concentration (>1%) of extract M. leucadendra caused turbid, greenish-gray color, and unpleasant smell on the water. Regarding the WHO bioassay guideline, etahnol extract of M. leucadendra leaves was less effective on killing A. aegypti larvae, though it causes lethal effect on it.