Abstract:
The greater wax moth (GWM) galleria mellonella is a ubiquitous pest of the
honey bee. The damage caused by G. mellonella is severe in tropical and sub
tropical regions, and is believed to be one of the contributing factors to the
decline in both feral and wild honey bee population. An integrated pest
management (IPM) is required to control the GWM, within which biological
controls play a key role. Bacillus thuringiensis is a gram positive rod shaped
bacterium which has an insecticidal property. Hence, the main objective of
this study was to isolate Bacillus thuringiensis and its effect against Galleria
mellonella under laboratory conditions.
100 soil samples were collected from different areas of Itahari, Tarhara,
Dharan and Vedetar. Out of 100 soil samples, 30 Bt isolates were obtained
which were tested against GWM larvae. Three different concentration of
crystal/spore mixture (1mg/ml, 500μg/ml, and 250μg/ml) was maintained.
Mortality was observed after the four days of inoculation. Among 30 isolates,
only four isolates showed an insecticidal activity. B. thuringiensis isolated
from Tarhara showed the 57.78% efficacy which was much more than other
isolates. The relation between treatment and control was statistically
significant (p<0.05). The mean difference was significant at 0.05 levels on
both bacterial death and survival. The result concluded that, there BT could be
safe microbial agent in managing GWM.
Description:
A
Dissertation
Submitted to the Department of Microbiology,
Central Campus of Technology Tribhuvan University, Dharan, Nepal
In Partial Fulfillment of the Requirements for the Award of Degree of Masters of Science in
Microbiology
(Agriculture)
By:
Jyoti Limbu
