Figure 9.

Leaf Necrosis in Transgenic Wheat with Multiple Genomic Copies of WKS1.

(A) Early senescence of 2nd leaves of WKS1 transgenic plants from two independent events (sibs 17a-4 /17a-15 and sibs 26b-6/26b-15) in the absence of Pst. Nontransgenic Bobwhite serves as control.

(B) Relative SPAD chlorophyll units of WKS1 transgenic or Bobwhite control plants. Samples were collected from the midsection of each leaf from the oldest (1st) to the youngest (flag leaf). Data points are means of eight measurements per leaves from 10 individual plants. Error bars are standard errors of the means.

(C) Quantification of H₂O₂ using an Amplex red hydrogen peroxide/peroxidase assay kit (Molecular Probes). Transgenic plants showed significantly higher H₂O₂ levels than the wild-type control (statistical contrast between the wild type and four WKS1 transgenic lines, P = 0.011). Samples were collected from the mid-region of the second oldest leaf from five to nine 5-week-old plants per genotype (growth conditions: 16 h light at 25°C and 8 h dark at 20°C). Error bars are standard errors of the means.