Studies on the activities of alkaline phosphatase and pathology of Bombyx mori infected with flacherie

In order to study the activities of alkaline phosphatase (ALKP) from flacherie infected silkworm and study the enzyme histopathology, the variation pattern of ALKP in the midguts of Bombyx mori were examined. It was demonstrated that the silkworm infected with Bacillus sp. was similar to that of healthy silkworm but with lower activities. Paraffin wax section of silk gland infected with flacherie showed that the tubes full of sericin-like substances. This obviously obstructed silkworms' spinning in the mounting stage. Cryosectioning technology was applied to determine the activity of ALKP substrate on silk gland. It showed strong reactions on the inner and outer membranes of silk gland from infected silkworms but only weak reactions were observed on the membranes of healthy silkworms indicating active phosphate transportation on the membranes. Intensely stained dots in fat body demonstrated the presence of ALKP synthesizing tissues.