Abstract: The efficiency of wood vinegar mixed with each
individual of three plants extract such as: citronella grass
(Cymbopogon nardus), neem seed (Azadirachta indica A. Juss), and
yam bean seed (Pachyrhizus erosus Urb.) were tested against the
second instar larvae of housefly (Musca domestica L.). Steam
distillation was used for extraction of the citronella grass while neem
and yam bean were simple extracted by fermentation with ethyl
alcohol. Toxicity test was evaluated in laboratory based on two
methods of larvicidal bioassay: topical application method (contact
poison) and feeding method (stomach poison). Larval mortality was
observed daily and larval survivability was recorded until the
survived larvae developed to pupae and adults. The study resulted
that treatment of wood vinegar mixed with citronella grass showed
the highest larval mortality by topical application method (50.0%)
and by feeding method (80.0%). However, treatment of mixed wood
vinegar and neem seed showed the longest pupal duration to 25 day
and 32 days for topical application method and feeding method
respectively. Additional, larval duration on treated M. domestica
larvae was extended to 13 days for topical application method and 11
days for feeding method. Thus, the feeding method gave higher
efficiency compared with the topical application method.
Abstract: Raw wood vinegar was purified by both standing and
filtering methods. Toxicity tests were conducted under laboratory
conditions by the topical application method (contact poison) and
feeding method (stomach poison). Larvicidal activities of wood
vinegar at four different concentrations (10, 15, 20, 25 and 30 %)
were studied against second instar larvae of housefly (Musca
domestica L.). Four replicates were maintained for all treatments and
controls. Larval mortality was recorded up to 96 hours and compared
with the larval survivability by two methods of larvicidal bioassay.
Percent pupation and percent adult emergence were observed in
treated M. domestica. The study revealed that the feeding method
gave higher efficiency compared with the topical application method.
Larval mortality increased with increasing concentration of wood
vinegar and the duration of exposure. No mortality was found in
treated M. domestica larvae at minimum 10% concentration of wood
vinegar through the experiments. The treated larvae were maintained
up to pupa and adult emergence. At 30% maximum concentration
larval duration was extended to 11 days in M. domestica for topical
application method and 9 days for feeding method. Similarly the
pupal durations were also increased with increased concentrations
(16 and 24 days for topical application method and feeding method
respectively at 30% concentration) of the treatments.