Functional categories of transcripts modulated in V riparia and V. vinifera following infection with P. viticola. Transcripts modulated in V. riparia (A) and V. vinifera (B) after infection with P. viticola at 12 hpi (left panels) and 24 hpi (right panels) were manually grouped in functional categories on the basis of literature evaluation. Induced genes are represented in light gray, while repressed ones are in black. The total percentage of modulated transcripts within each category is shown next to each bar. The complete list of genes is available in Additional file 6.