Ecophysiology of after-fire resprouts of Arbutus unedo L

Plant-water relationships, leaf morphology and concentrations of pigments, proline, soluble sugars, anthocyans and nutrients of after wildfire resprout leaves of Arbutus unedo L. were com-pared with those of same age sprout leaves in unbumed plants. In spring samples, several significant differences appear: after-fire resprouts showed some juvenile characteristics, such as high tissue elasticity, small cells, low specific leaf weight, high Chla/Chlb ratio and a high anthocyan content; on the other hand, unbnrned plants showed drought tolerance characteristics by osmotic adjustment and lower tissue elasticity, larger cells, higher specific leaf weight and lower Chla/Chlb ratio. In fall samples, both kind of shoots showed drought tolerance by osmotic adjustment, low tissue elasticity, large cells and high specific leaf weight. Results show that after-fire resprouts have, at the beginning of their development, higher morphological and physiological plasticity that the new sprouts of unburned plants.