Physiological and ultrastructural effects of acute ozone fumigation in the lichen Xanthoria parietina: the role of parietin and hydration state

作者：Vannini Andrea; Paoli Luca; Ceccarelli Sara; Sorbo Sergio; Basile Adriana; Carginale Vincenzo; Nali Cristina; Lorenzini Giacomo; Pica Mario; Loppi Stefano^*

来源：Environmental Science and Pollution Research, 2018, 25(9): 8104-8112.

DOI：10.1007/s11356-017-9545-9

• Air pollution
• Biomonitoring
• Chlorophylla fluorescence
• Ergosterol
• Parietin

The physiological and ultrastructural effects induced by acute exposure to ozone (O-3) were investigated in the lichen Xanthoria parietina. Our working hypothesis was that parietin content and hydration of the thalli may play a role in the modulation of the effects of O-3 exposure. Four batches of X. parietina samples, dry and wet, with (P+) and without (P-) parietin, were fumigated for 1 h with 3 ppm O-3. The effects of O-3 were assessed immediately after the fumigation and after one week of recovery under controlled conditions. O-3 fumigation caused physiological and ultrastructural impairment both to the photobiont and the mycobiont, irrespective if samples were fumigated wet or dry, and P+ or P-. However, one week after fumigation, a recovery was observed in P+ samples for the photobiont and in dry samples for the mycobiont. We suggest that the hydration state may play a major role in determining the severity of the damage, while the presence of parietin may promote the recovery. Our results provide physiological and ultrastructural basis to explain the ecological insensitivity of lichens to high environmental levels of ozone occurring during dry Mediterranean summers.

• 出版日期2018-3