Heatmap of normalized intensity values obtained from cowpea microarray at 0.1% FDR threshold. Material collected represent resistant and susceptible cowpea- Striga interaction at early (6 dpi) and late (13 dpi) stage of Striga attachment. Genes were clustered based on their intensity values profile across treatments and expressed as 6 groups linked by a dendrogram. Representative genes from these various clusters on the heatmap are labeled on the side. Each treatment (A = control, B = SG3 6 dpi, C = SG3 13 dpi, D = SG4z) consisted of three independent biological replicas. Genes with relatively high intensity values versus all treatments are marked red. Genes with relatively low intensity values compared across treatments are marked blue. Genes with average intensities compared to other treatments are marked white.