Fig. 4.

Single-cell death assay in wheat leaves. Wheat leaves of cv. Kanzler were co-bombarded with pUbiGus as a transformation marker, pEG101 for overexpression of ZtSSP2 (PEG101:ZtSSP2), and the B-Peru/C1-expression plasmid pBC17 that induces anthocyanin accumulation in wheat epidermal cells. (A) Unstained wheat leaf showing epidermal cells that accumulate anthocyanin (arrow; scale bar=20 µm) 4 d after bombardment and (B) GUS-expressing cells after GUS staining. (C) Quantification of the relative number of anthocyanin-producing cells calculated as the ratio of anthocyanin-accumulated cells to the number of GUS-expressing cells. Co-transformation of pBC17 and pUbiGUS with the empty vector pEG101 and pEG101:Zt-6 served as a positive control inducing cell death. Values are the means of four independent experiments with seven leaves counted per repetition (bars ±SEM). The asterisk on top of the bar represents significant differences determined by Tukey test (*P<0.05).