Method for preparing inhibitor for reducing tobacco nicotine synthesis by using double-stranded RNA interference technology, and applications of inhibitor

The present invention discloses a method of inhibitor and their use for preparing a double-stranded RNA interference with reduced tobacco nicotine biosynthesis, the method to extract the RNA of tobacco, reverse transcription tobacco putrescine -N- methyl transferase ( PMT) gene cDNA; and by PCR amplification of cDNA of the fragment; then connect the available RNA expression plasmid vector PET-21a; and the plasmids were transformed into missing RNAE3 enzyme E. coli cells expressing hairpin dsRNA ; disrupting the cells, resulting dsRNA crude preparation, the dsRNA crude preparation sequentially adding glycerol, protection and dispersing agents, can be reduced tobacco nicotine synthesis inhibitors. The resultant inhibitor is 5 ~ 15mL / strain applied to the tobacco, reducing tobacco nicotine synthesis. Simple production of the present invention, low cost, to humans and animals and higher animals harmless, is suitable for mass administration on the tobacco, has broad prospects for industrialization.