In our study, two silkworm strains, namely Qiufeng which is resistant to DNV and Huaba35 which is highly susceptible to DNV and their isogenic line BC_6, were used for screening molecular markers by using 495 RAPD random primers in DNA mixtures of these strains respectively.One molecular marker named S366 was found to link with major gene resistant to DNV,then it was cloned and sequenced.According the sequence, special primer was synthesized and tested in several silkworm strains which are highly susceptibl...