Morphological analysis of citrange trees. A) Images showing morphological differences observed between tetraploid (4n) and diploid (2n) lines. Image on the left: differences in the coloration and leaf density of the trees; image on the right: differences in the morphology of their leaves and flowers. B) The effects of the ‘line’, ‘transgene’ and ‘ploidy’ factors on the morphological variables Tree height, Tree canopy volume, Leaf fresh weight and Leaf area. The data represented in the notched box-and-whisker plots were calculated from measurements recorded over the course of two years (2004 and 2005) at the end of the growing season. K-W, Kruskal-Wallis test (n = 48); M-W, Mann–Whitney tests; 2n, all diploid lines (n = 40); 4n, all tetraploid lines (n = 8); C, control line CC (n = 16); T, all transgenic lines, except tetraploids C2 and C7 (n = 24).