Figure 2

Estimation of genomic DNA quantity and quality. Bar graph represents average estimated DNA concentrations from at least 50 extracted samples (A; ng/μl), as defined by gel density analysis (white bars), or spectrophotometric determinations using a NanoDrop spectrophotometer (blue bars). Results were obtained for DNA samples extracted using Promega's Genome Wizard kit (I), the Nucleon Phytopue Kit (II) or the CTAB-homebrew method (III). Collated absorbance ratios obtained from the same samples at 260: 280 nm (green bars), or 260: 230 nm (grey bars) are shown. DNA quantity and integrity was assessed by resolving DNA samples (extracted from Bt11 maize reference material; 0%, - 5%) on 0.8% TAE agarose gels by electrophoresis. Representative samples extracted using Promega's Genome Wizard kit (B), the Nucleon Phytopue Kit (C) or the CTAB-homebrew method (D).