Fig. 7

Expression patterns of maize B73 genes during stem development derived from hierarchical clustering. Transcript levels in rind tissues from Internodes 2 through 9 were normalized. a Pattern 1 (Elongation) shows highest expression in the younger internodes, a stage associated with elongation stages and primary wall formation. b Pattern 2 shows low expression during elongation stages, with either low (Transition I) or high (Transition II) expression in older internodes. c Pattern 3 (Secondary) shows low expression in younger internodes and increasing in older internodes. d Pattern 4 (Early & Late) shows moderate to high expression during early elongation stages, decreased expression during peak secondary wall formation, and returns to elevated expression during late secondary wall formation