Fig. 6.

Histological analysis of the apical meristematic region of lateral roots in SR1, rolB and rolB-AtPCS1 after 9 days of treatment. a–c Regular structure in roots of plants grown without Cd and As (Control). d–f Vacuolation in the ground meristem forming the cortex, as magnified in the insets, and thinning of the still meristematic endodermis (arrowheads) of roots exposed to 60 μM CdSO₄ (60 Cd). g–i Almost regular structure of roots exposed to 200 μM Na₂HAsO₄.7H₂O (200 As). j–l Vacuolization in the forming cortex of roots exposed to 50 μM Na₂HAsO₄.7H₂O plus 60 μM CdSO₄ (50 As + 60 Cd). Transverse sections. Bars 20 µm (a–c and insets in d, f), 30 µm (d–l)