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The tobacco A (Lasioderma serricorne) is a worldwide important storage pests. Up to hundreds of millions of dollars of annual global losses caused by this pest. The conventional methods of prevention and treatment of tobacco A drug resistance, and the pollution of the environment. Bacillus thuringiensis (Bacillus thuringiensis referred to as Bt) control effect is remarkable, the most widely used microbial pesticides. Starting from the nineties of the last century, the scholars of the world has begun to work of Bacillus thuringiensis on the prevention and control of the cigarette beetle. Prepared from the three aspects of the soil, tobacco, plant leaves the the bacteria source material 258 parts inhibition assay 19 containing the parasporal crystal of Bacillus thuringiensis separated therefrom, the use of sodium acetate, crystal morphology in a diamond, and the presence of a small amount of a rectangular . Total detection rate of 7.36%. The three materials, the detection rate of tobacco samples up to 13.33%, fully shows that the tobacco leaf is one of the critical habitats of Bt survival. (Cornmeal, and yeast extract at a 10:1 ratio mixed) dubbed feed successfully grow tobacco A 30 ℃, RH75% conditions, the use of feeding foodstuff. The test results show that the nutritional composition and physical properties of the feed might be interested in the cigarette beetle growth have been affected. Cultivate tobacco A 2-3 day-old larvae and separation of Bt strains biometric screening out high virulence strains of Bt strains of tobacco beetle larvae, numbered 115,106,119,117,121 207 the first 10 days of the corrected mortality of 48.28%, 55.17%, 58.82%, 68.97%, 51.73% and 48.28%, respectively. Rescreening, 6 to 12 days corrected mortality were 48.28%, 51.73%, 58.62%, 72.41%, 51.73%, 44.83% lethal concentration (LC 50 ) were 43.89057 , 42.60283,38.64439,29.02226,43.72312,52.42485 mg / L, No. 117 strains best insecticidal effect of screening of the cigarette beetle with high virulence strains. Then strain Bt117 morphological, physiological and biochemical characteristics and the identification of the 16s rDNA. The the appraisal results showed that: the bacterium vegetative form of rod-shaped, rounded at both ends, arranged in single or multiple chain; crystal diamond-shaped, large and small; colonies disc-shaped, the color of milky surface radioactive wrinkles; measured physiological and biochemical characteristics consistent with Bacillus thuringiensis characteristics; the measured bacteria 16SrDNA sequence of several modes of Bacillus thuringiensis, such as Bacillus thuringiensis strain 2000031482 sequence similarity up to 99%; preliminary determination strain Bt117 Bacillus thuringiensis.
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