Selection and molecular confirmation of transgenic Arabidopsis plants. A. Arabidopsis plants used for floral dip transformations; B. DNA construct used for transformation; LB: left border, RB: right border, FLS2: flagellin sensing locus 2, PAT: phosphinothricin acetyltransferase conferring BASTA resistance, NOS: nopaline synthase, pro: promoter, BLA: β-lactamase conferring ampicillin resistance, ori: origin of replication, UTR: untranslated region, term: terminator. C. Surviving plants following 2 weeks of BASTA selection; D. DNA gel blot analysis: Plant genomic DNA from transformed and non transformed plants (WT, fls) from different genetic backgrounds (Col, Ler, Ler fls) was digested with Stu I, the fragments electrophoretically separated and blotted onto a nylon membrane. The blot was probed with the Stu I/Xba I fragment of the FLS2 coding sequence (left panel) and, after stripping, reprobed with the Hinf I fragment of the vector backbone (right panel). 4.4 kb indicates the size of the endogenous FLS2 Stu I fragment, while 9.8 kb corresponds to the full size vector DNA digested with Stu I.