Two primers were deslgned and synthesized according to the DNA sequence of spores of Nosema bomby(-is (Nb )from silkworm. The DNA of Nb spores and its related species (strain) were amplified separately by polymerase chain reaction (PCR ). The results showed a specific amplification in the DNA of Nb spore and the DNA fragment was about 317 bp, which distinguished N. bombycis from Nosema sp. MG1 and MG2, microsporidias of Antheraea pernyi, Vairimorpha necatrix, Pleitsophora anguillarum, etc.The detective sens...