Every year dengue disease which is caused by bites of Aedesaegypti
mosquito mostly end in mortality. Spread prevention of this disease need much
comprehensive handling. One way to eradicate larvae of mosquito A.aegypti is
using its natural enemy Bacillus thuringiensis. Research has been done in
Yogyakarta Special Province area which is including Yogyakarta City, Sleman,
Gunungkidul, Bantul, and Kulonprogo districts. Research has been done in
Technobiology Laboratory, Faculty of Technobiology, University of Atma Jaya
Yogyakarta. Isolation of B.thuringiensis was using Ohba and Aizawa method.
There are two phase of research. First phase was selective isolation, identification,
iv
gram staining, and screening test of killing power of strain B.thuringiensis to Ae.
aegypti’s larvae, pathogenicity test and probit analysis. The second phase was
selection of B.thuringiensis which its virulence bigger or similar with 80%, isolate
multiplication of virulent B.thuringiensis, pathogenicity test of B thuringiensis
which is most virulent and laboratory scale bio insecticide production. Results of
first phase showed that 19 of 74 isolates of B thuringiensis have a virulence of
80%. Pathogenicity test LC 50/ 24 hrs., showed effective concentration of 2.04 x
105. Results of the pathogenicity test of the second phase showed that one of 19
isolates was strongly virulent. The most pathogenic isolate was 75P. Isolate 75P
can be used as raw material for natural bioinsecticide.