Evalution of Nicotine Changes in Tobacco (Nicotiana tabacum L.) Plants Mutated by T-DNA

Nicotiana tabacum contains nicotine, Which is used in cigarettes causing many health problems. Application of new technologies such as, plant tissue culture, genetic engineering in order to block the pathway of nicotin biosynthesis, and somaclinal variation can be used as tools to produce plants with a lower level of nicotin. The aim of this research is to evaluate nicotine changes in tobacco plants mutated by T-DNA. In this research transgenic plants including K4 carrying T DNA, plants carring Ri TDNA and regenerated plants from leaf and wild type plants (mother plants) were grown on MS medium containing canamycin. Leaves were harvested and dried, and extracted with hexan as internal standard. Then analysed using TLC and GC. The analysis of the extracts showed that nicotine content decreased in line k4 (containing T-DNA) and increased in Ri-TDNA (plant containing Ri-TDNA) and regenerated plants compared to non mutated plants. Variation of nicotine content in mutated plants might be related to the activation or inhibition of the key enzymes involved in nicotin biosynthesis pathway.