13664 10.30848/PJB2026-6(13) <p> The responses of antioxidant enzymes of gene expression and activity to salinity in <em>Ilex verticillata</em></p> Jiaxin Zhuge, Bing Si, Wenyan Ge, Ying Chen, Ruiqi Wang and Yichen Lu <p style="text-align: justify;"> <em>Ilex verticillata</em> is a deciduous shrub of great ornamental and commercial value owing to the red fruits that hang on its branches in winter. However, little is known about its salinity adaptability and mechanisms. Here, we investigated the mechanism of antioxidant gene expression and enzyme activity responses to salinity in <em>Ilex verticillata </em>under 50-100 mM NaCl treatments. Our results showed <em>I. verticillata </em>cutting seedlings were slightly affected under 50 mM treatment. However, 100mM NaCl inhibited the cutting seedlings growth, damaged chloroplasts and cell structures, and led to O₂^.-and H₂O₂ over-accumulated, whereas it was observed that the leaves fell off and new buds grew at NaCl treated for 20 days. In contrast, peroxidase (POD), catalase (CAT), and glutathione reductase (GR) activities, and AsA (ascorbic acid), GSH (glutathione) contents were significantly enhanced. Therefore, <em>I. verticillata</em> cutting seedlings could tolerate stress as high as 100mM NaCl by wilting young leaves to preserve buds. There were dose effects and time effects in enzyme activities and gene expressions. The enzyme activities (SOD, CAT and APX) and transcript levels (<em>IvCu-ZnSOD</em>, <em>IvCAT </em>and <em>IvAPX</em>) of cutting seedlings were asynchronous under 100mM NaCl treated for 20 days. This may be due to the synthesis and activation of enzymes lagging behind gene expression. This work would provide a reference for the cultivation of new varieties, and the breeding of elite genetic resources for salt tolerance. This is the first detailed report on salinity tolerance in <em>I. verticillata</em>.</p> <p> &nbsp;</p> Published 2026 58 6 1207 1218