Excision increases local expression of auxin-responsive and cell division reporters in adventitious roots developing from pericycle cells. A, Intact or root-excised hypocotyls of pIAA2:GUS, pGH3-2:GUS, pDR5:GUS, and AtCYCB1;1:GUS were stained at the indicated time after excision. Insets show a 2.5× view of the hypocotyl base or the equivalent region in intact seedlings. Bar = 1 mm. B, Higher magnification images of intact or root-excised hypocotyls of AtGH3-2:GUS and AtCYCB1;1:GUS were stained 24 h after excision or in time-matched intact controls. Bar = 50 µm. Labels correspond to different cell files. P, Pericycle; V, vascular bundle; C, cortex; E, epidermis; A, adventitious root primordia.