2.7 Image analysis and statistics
The transverse areas of the leaf vascular tissues were manually
outlined, individual tube number counts and length/width measurements
evaluated on images with the Image J 1.51d software (National Institutes
of Health, Bethesda, MD, USA). Individual images from stem cross
sections were aligned and merged into a composite image with the
Photoshop software (Adobe Systems, Newton, MA, USA).
Averages from geometrical evaluations were compared using a one-way
ANOVA and the post hoc Tukey test at a p <0.05, using
the SPSS software for statistics.