2.5. DNA extraction and molecular studies
DNA was extracted from fresh leaf tissue (∼200 mg) of threeweekold plants with the Pure gene DNA isolation kit (Gentra,Minnesota, USA) according to the manufacturer’s instructions.Known primers were used to sequence the psbA gene . Forthe ACCase gene, primers were designed using known sequence of L. rigidum . Genes were amplified and PCR products were sequenced to locate the common point mutations that can endow TS resistance. Sequence analyses and alignment were performed using Bio edit software . The obtained sequences were compared to the known psbA and ACCase sequences of Arabidopsis thaliana and B. distachyon.