Abstract:Abstract:【Objective】We screened dominating microbial species isolated from aging flue-cured tobacco and studied their aroma improving effect.【Methods】Total DNA of microorganisms from the fermentation flue-cured tobacco surface of NC89, ZhongYan 100 and ZhongYan 101 were extracted. Under the PCR-DGGE, the diversity of microorganisms on fermentation tobacco leaves were studied and dominating microbial species were screened. We further studied the influence of dominating microbial species on the content of aroma components of the fermentation flue-cured tobacco.【Results】1) By using DGGE analysis, there were 5 dominant bands A, B, C, D and E in all tobacco leaves samples of the three varieties; In further studies, five dominant DGGE bands were isolated, cloned and sequenced. From them we screened a dominant microorganism. 2) The content of most aroma components in tobacco leaves increased when they were sprayed with the dominant microorganism, comparing with the control.【Conclusion】The dominant microorganism can improve the flavor of tobacco leaves during ripening.