家蠶에서 分離된 새로운 微胞子蟲 K79의 病理學籍 硏究 : Ⅱ .微胞子蟲의 病原成 및 發育經過 Ⅱ.Pathogenicity and Developmental Progress of the Microsporidia = Pathological Studies on the New Microsporidia K79 Isolated from the Silkworm, Bombyx mori L.

다국어 초록 (Multilingual Abstract)

In order to clarify the taxanomic position of a new microsporidia K79 which was isolated from the silkworm larvae, Bombyx mori L. in Korea in 1979, the following several experiments such as estimation of pathogenicity in diferent instar, histopathological examination under light and electronic microscope and examination of fine structures of the spores were carried out and their results obtained are as follows.
In the test of pathogenicity by oral inoculation, the new microsporidia K79 was lower than Nosema bombycis and the susceptibility of the new microsporidia to silkworm was getting lower as the silkworm larvae grew. The lesion of Silkworms' tissue which was infected with the new microsporidia K79 was found in the epithelial cells of trachea, fat body and silk gland cells.
The developmental process of the new microsporidia K79 in vivo could be divided into the following five stages: sporoplasm, schizont, sporont, sporoblast, and spore. This process was just the same as that of N. bombycis, but its development was slower than that of N. bombycis.
Several differences in the fine structure of the spore under electron microscope, which could be important keys for the classification of microsporidia, were obtained. Anchoring disk and polaroplast lamella of the new microsporidian spore were disclosed to be different from those of N. bombycis. An average number of polar filament coils of the new microsporidian spore was 16 at an angle of 75°.
On the basis of various keys for the classification of microsporidia, the results obtained from various experiments proved that the newly isolated microsporidia should be classified into the Genus, "Nosema", but its further classification for species should be conducted in the future. Therefore, it may be reasonable that the new microsporidia is temperally classified as Nosema sp. K79 considering the fact that it was discovered in Korea in 1979.