Fig. 4From: The influence of nitrogen availability on anatomical and physiological responses of Populus alba × P. glandulosa to drought stressAnatomical properties of stem under each combined treatment of water and nitrogen. a adequate nitrogen and drought; b adequate nitrogen and well-watered; c low nitrogen and drought; d low nitrogen and well-watered. Epi, epidermis; cor, cortex; ph, pholem; xyl, xylem; Bar = 200 μmBack to article page