Genetic Transformation Of Arabidopsis Thaliana And Brassica Napus With Herbicide-Resistant Gene Dsals

Brassica napus L. is the second largest oilseed crop of the world. It has immense importance in the economy of China being the biggest producer of oilseed brassica in the world. Weeds are the major threat to canola production. As a result of the highest practical advantage chemical herbicides are use on broad spectrum to get rid of weeds,besides the useful impact because of high penetrance these chemical herbicides deteriorate the quality of oilseed. The best solution to combat this issue is to create genetic resistance in the crop plants against these herbicides. Keeping in view this problem, present study is initiated with the ALS (Acetolactate synthase) herbicide resistance gene from Descurainia Sophia mutants,it was transferred into B.napus via Agrobacterium-mediated transformation, we got a batch of transgenic plants, which can provide breeding materials for improving rape varieties by transgenosis. The main results of this study are as follows:1. DsALS-1gene,DsALS-97gene and DsALS-108gene were respectively cloned from wild type and two natural mutant of D. sophia named1,97and108. Comparative analysis of three mutant genes with A. thaliana revealed a point mutation at position197of the ALS gene by substitution of proline with serine in DsALS-97, threonine in DsALS-108while DsALS-1have no target site mutation.2. Three genes were transformed into A. thaliana via Agrobacterium-mediated transformation. Herbicide Tribenuron-methyl (family:sulfonylurea) is used to apply selection pressure on transgenic plants. Transgenic Arabidopsis plants carrying DsALS-97and DsALS-108gene exhibited resistance to tribenuron-methyl, whereas DsALS-1transgenic plants show no resistance. This result is consistent with the comparative analysis results.3. DsALS-108was transformed into into B.napus (Zhongshuang No.9and Jia572) via Agrobacterium-mediated transformation.23and19transgenic plants were obtained with the rate of positive plants12.4%and22.4%for Zhongshuang No.9and Jia572respectively. 4. Gene transformation is confirmed by PCR in T1transgenic lines. RT-PCR analysis further confirmed the stable inheritance and expression of DsALS-108gene at the transcriptional level in transgenic plants.