Detection of vector backbone sequence in siblings of BS^R-12. (A) Southern blot analysis of T₂ progeny of BS^R-12 named BS^R-12-1 to BS^R-12-8. *GT vector was added to the WT. The position of the probe is shown in Fig. 1A. (B) PCR analysis using primers located near the LB and RB (Fig. 1A). Amplification of PCR products in BS^R-12-1, 2 and 4–8 means that not only the T-DNA region but also the vector backbone sequence is integrated in these plants. The positions of the primers are shown in Fig. 1A.