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Tobacco industry is an extremely important revenue in our country. With the fast development of our country tobacco industry, the scale and amount of stored tobacco become bigger and bigger, and the store time is also extension. For a long time, because of the backward store facilities and extensive management, tobacco usually suffer from various fungi during the period of the storage. It is an urgent matter to investigate the mold causing agents in stored tobacco and prevent the tobacco from mold at the moment.At our country, the research in mold tobacco drop behind, the fungi category which causes the tobacco leaves mold only has a handful of reports, and the existing fungicides are partially ineffective or have side effect to the human body, so it is important in practice and theory to build up a set of techniques that can be used in examination of stored tobacco quickly and look for a kind of useful, safe, effective, suitable fungicides.We started with more than 100 mold tobacco samples provided by Changde Cigarette Factory. After isolation, purification and preservation, the pure culture of 5 kinds of fungi were acquired. Then, we observed shape and size of mold fungi under microscope, and identified them as 3 genera roughly. For the further identification of the mold fungi, we extracted DNA, amplified 18S rDNA ITs by PCR, cloned PCR product and detected the sequence. Through BLAST, we make sure five kinds of pathogenic fungi are Fusarium sp., Aspergillus oryzae, Aspergillus terreus, Aspergillus niger, Penicillium citrinum. In laboratory bioassay, 75%Dacotech, 40%Dimethachlon, 98%Kang -zhuoling, 100%Dimethyl fumarate medicine were tested for their effect. The result showed that 40%Dimethachlon is the best in inhibition spectrum and antibiotic effect at dilution of 3000 times (130.32mg/kg) with inhibitory rate of over 95%. DMF is the second, and inhibitory rate is over 95% at the concentration of 490mg/kg. 98% Kangzhuoling, a new traditional Chinese medicine, gave good inhibition with inhibitory rate of over 95% at the concentration of 490mg/kg. It might be a low toxic, safe, effective biologic mold inhibitor.
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