02118naa a2200253 a 450000100080000000500110000800800410001910000200006024501110008026000090019152013470020065000290154765000210157665000240159765000270162165000130164870000200166170000240168170000200170570000190172570000250174470000220176977300730179111358822025-10-06       2025    bl uuuu     u00u1 u    #d1 aOLIVEIRA, L. M.  aEthylene plays a key role in the infection of maize leaves by Exserohilum turcicum.h[electronic resource]  c2025  aNorthern corn leaf blight (NCLB), caused by the fungus Exserohilum turcicum, is one of the major foliar diseases in maize causing significant decreases in grain yield. In this study, it was hypothesized that the basal level of resistance of maize plants against NCLB, after being exogenously exposed to ethylene (ET), could be lowered as a result of less effective participation of defense-related and antioxidative enzymes. Maize plants were sprayed with ET, aminooxyacetic acid (AOA) (an ET inhibitor), and water (control). In contrast to the leaves of water- and AOA-sprayed plants, the foliar symptoms of NCLB progressed rapidly for ET-sprayed plants from 8 to 16 days after inoculation. The increase in NCLB symptoms could be linked to the lower activities of defense (chitinase, β-1,3-glucanase, lipoxygenase, and phenylalanine ammonia-lyase) and antioxidative (ascorbate peroxidase, glutathione reductase, and superoxide dismutase) enzymes. The expression levels of genes related to ET metabolism (ACS2, ACS7, ACO20, ACO31, BAK1, and BZR1) significantly increased in the leaves infected by E. turcicum in contrast to non-infected leaves mainly when they were sprayed with ET. Taken together, the results of the present study showed that the spray of maize leaves with ET greatly contributed to the infection process of E. turcicum  aAntioxidative metabolism  aFungal infection  aHormonal metabolism  aHost defense reactions  aZea mays1 aEINHARDT, A. M.1 aRODRIGUES, F. C. T.1 aSILVEIRA, P. R.1 aRIBEIRO, D. M.1 aWORDELL FILHO, J. A.1 aRODRIGUES, F. ??.  tTropical Plant Pathology, Brasilia, DFgv. 50, n. 48, p. 1-14, 2025.