02676naa a2200277 a 450000100080000000500110000800800410001910000200006024501520008026000090023252018030024165300160204465300200206065300200208065300240210065300250212465300240214965300250217365300230219870000200222170000200224170000190226170000250228070000210230577300720232611290482019-10-30       2019    bl uuuu     u00u1 u    #d1 aSILVEIRA, P. R.  aChanges in leaf gas exchange, chlorophyll a fluorescence, and antioxidants in maize leaves infected by Exserohilum turcicum.h[electronic resource]  c2019  aConsidering the importance of northern leaf blight, caused by Exserohilum turcicum, to decrease maize yield, this study evaluated electrolyte leakage, content of H2O2, malondialdehyde (MDA), chlorophyll (Chl) a, Chl b, and carotenoids (CAR), and activities of superoxide dismutase, catalase, ascorbate peroxidase, peroxidase, glutathione reductase, glutathione-S-transferase, and glutathione peroxidase, as well as expressions of superoxide dismutase (sod), catalase (cat 1), ascorbate peroxidase (apx 2), peroxidase (pox), glutathione reductase (gr 1), and glutathione-S-transferase (gst 23) genes, and leaf gas exchange and Chl a fluorescence parameters in maize leaves infected with E. turcicum. The content of H2O2 and MDA was high at 15 and 20 d after inoculation (dai) and electrolyte leakage was high from 10 dai onward in infected leaves. Net assimilation rate, stomatal conductance to water vapour, transpiration rate, internal CO2 concentration, maximum quantum yield of photosystem (PS) II, and effective quantum yield of PS II significantly decreased as the disease developed. Quantum yield of regulated energy dissipation significantly increased at 10 and 15 dai but decreased at 20 dai whereas the quantum yield of non-regulated energy dissipation significantly increased at 15 and 20 dai. The content of Chl a, Chl b, and CAR decreased in infected leaves. The activities of the enzymes increased, and the relative expressions of the genes sod, cat 1, apx 2, pox, gr 1, and gst 23 were higher in infected leaves compared to non-infected ones mainly from 10 dai onward. In conclusion, photosynthesis in infected leaves was dramatically affected and a late involvement of the antioxidant metabolism was not sufficiently helpful to counteract the deleterious effects of fungal infection.  acarotenoids  agene expression  amalondialdehyde  anecrotrophic fungus  anorthern leaf blight  aphotosynthetic rate  astomatal conductance  atranspiration rate1 aMILAGRES, P. O.1 aPEREZ, C. E. A.1 aCORRÊA, E. F.1 aWORDELL FILHO, J. A.1 aRODRIGUES, F. A.  tBiologia Plantarum, Czech Republic.gv. 63, n. 1, p. 643-653, 2019.