Figure 1

Northern blot analysis for the induction of proteinase inhibitor II (Pin-II) and PR protein P4 mRNA transcripts by wounding (W), potato aphid feeding (A) or Colorado potato beetle chewing (CPB) in potato leaves. Each bar is the mean of three independent (plant replicate) values ± se. Leaf total RNA was extracted 24 h after initiating the stress treatments. The membranes were hybridized with ³²P-labelled cDNA probes for either Pin-II or Protein P4. Equal RNA loading in each well was controlled by ethidium bromide fluorescence of total RNA fixed onto the membrane. C, control leaves from healthy, non-treated plants.