| According to isolation, identification, physiological assay and fungicide test tomildew to stored tobacco, along with monitor temperature and humidity of storedtobacco, fungicide control of mildew, assay of fungicide rudimental ,discussed thepathological mechanism and managed measurement ,this research acquired thefollowing mostly result.1. Identification of mostly fungus mold on stored tobacco Now the mold fungus which caused stored tobacco to grow mildew had beenidentified, they were Aspergillus, Penicillum, Mucor, Rhizopus. A. niger v. Tiegh., A.flavipes (Bain.& Sart.) Thom & Church, A. sydowii (Bain. &Sart.) Tomb&Church., P. expansμmLind, M. racemosμs Fres, R.. stolonifer(Ehrenb.ex Fr.)Lind were main species.2. Biological characteristic of mold fungus on stored tobacco The effect of temperature and humidity on stored tobacco mildew hyphal growthrate,conidia germination and germ tube elongation were conducted . The results reported as follows: the temperature range from 10℃ to 35℃thehyphal of Aspergillus, Penicillum, Mucor could survived,they were optimum at 25℃,Low temperature such as 0℃ inhibited hyphal growth and conidia germination only,but was not the deadly line.but range from 10℃ to 40℃ the hyphal of Rhizopuscould survived,they were optimum at 35℃. It was beneficial for conidia germinationand germ tube elongation from 20℃ to 30℃ ,conidia germination was optimum at25℃,germ tube was congest at 30℃ than that of other temperature ,but Rhizopusrange from 25℃ to 40℃, conidia germination was optimum at 35℃.Mildewincubated by liquid culture medium , Aspergillus and Penicillum hyphal dry weightwere the heaviest at 25℃, Mucor and Rhizopus hyphal dry weight were the heaviestat 10℃ and 35℃, respectively. When the surrounding relative humidity was at70%～75%, hyphal grew the best; but Penicillum and Mucor at 90%, Rhizopus at85%. Conidia germination requested high humidity condition, when the relativehumidity was more than 60%, Conidia germinated better in free water than in waterfilm.3. The control effect of five fungicides on stored tobacco mildewcaused by mold fungus This paper screened the effective single fungicides and their applicationtechniques to control mold fungus. Bioassay result showed that the five fungicidescould inhibit the growth of hypha of mold fungus, but the concentration of inhibitionand the way of effect were different. Effective concentration(EC50) of propionic Acid,Acid cactic, Fumaric acid and Methyl p-hydroxy benzoate to inhibit the growth of thehypha of M.racemosus Fres.was 1.4133, 1.3139, 0.6156μg/mL and 1.3642μg/mL,repestively. The efficiency of control of DMF acquired 100%,the concentration ofinhibition of germ tube elongation was 3.1538,2.3688,1.9130,2.5592 μg/mL and0.0300 μg/mL, respectively. Effective concentration(EC50) of A. niger v. Tiegh to inhibitthe growth of hypha was 1.8340, 3.7628, 1.4998 μg/mL and 1.1140 μg/mL, respectively.The efficiency of control of DMF acquired 100%,the concentration of inhibition ofgerm tube elongation was 3.8194, 4.0340, 4.4710, 3.8107 μg/mL and 0.1192 μg/mL,respectively. Effective concentration(EC50) of R.. stolonifer(Ehrenb.ex Fr.)Lind to inhibitthe growth of hypha was 2.0642, 0.0369, 1.2220, 1.6853 μg/mL and 1.4375 μg/mL,respectively. The concentration of inhibition of germ tube elongation was 1.9209,1.9895, 3.1923, 2.6737μg/mL and 1.2378μg/mL. Effective concentration(EC50) ofA. flavipes (Bain.& Sart.) Thom & Church to inhibit the growth of hypha was 1.0039, 1.2967,1.2756,1.2691 μg/mL and 0.9552 μg/mL, respectively. The concentration ofinhibition of germ tube elongation was 2.2882,3.4324,2.9719,2.932 μg/mL 8 和0.5833 μg/mL. Effective concentration(EC50) of P. expansum Lind to inhibit the growth ofhypha was 2.3451,5.6874,1.5337,1.2992 μg/mL and 1.2985 μg/mL, respectively. Theconcentration of inhibition of germ tube elongation was 2.3737, 7.4281, 2.7819,1.1462 μg/mL and 1.4570 μg/mL. Effective concentration(EC50) of A. sydowii (Bain.&Sart.) Tomb&Church. to inhibit the growth of hypha was 1.8771...
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