Figure 1

Principal component analysis (PCA) of the expression matrix of the species-specific hybridization experiment. PCA of 14,868 genes, across 8 microarray hybridizations of potato RNA to potato microarray (PP). Axes 1 and 2 account for 59.7 and 15.6 % of the variation, respectively. The hybridization datasets are labeled according to treatments; '+' or '-' designate infected or non-infected tissues, respectively; '10' or '5' designate 10 or 5 days of nematode infection. Biological replicates are circled.