Isolation and culture of the intestinal bacteria
Guts of healthy and diseased A. proylei larvae were homogenized in 0.86% NaCl solution (Broderick et al., 2004).The stock solution was prepared by taking 1 ml of the suspension and was mixed with 9.0 ml saline. Using the serial dilution method seven dilutions were prepared. 1ml of each dilution was added to a separate plate in triplicates. Then 15 ml of nutrient agar was added to each medium and incubated for 24 hours at 37°C. The dominant colonies were identified, purified three times by successive inoculation and culture on the corresponding agar plates, and further transferred to agar slants (Huang & Xin, 1999).