Fig. 4.

A heat-map display of log2 ratios for the expression results of real-time PCR. A black box indicates a strong up-regulation, a neutral grey box equivalent expression, a white box a strong down-regulation, and shades of grey in between indicate intermediate levels of regulation. Expression profiles for each gene were grouped by hand to cluster genes with similar expression profiles. RNA was isolated from whole roots and trimmed root pieces of SCN-colonized roots or non-inoculated roots at the indicated dpi, and non-inoculated whole roots and root tips dissected at 0–2 and 2–7 mm proximal to the root apex. Where RNA was extracted from SCN-inoculated and non-inoculated whole roots or root pieces, the ratio is for the means for biological replicates of root collections taken at the same dpi. Root tip dissections are relative to the expression in whole roots collected at the same time as the root tips.