As a plant growth regulator, brassinolide (BL) is essential for enhancing plant growth and development. Studies on how BL affects the growth and development of prickly ash (Zanthixylum schinifolium) are scarce, nevertheless. Thus, the purpose of this study was to investigate how Z. schinifolium growth and development were affected by the application of BL (0, 0.1, 0.2, 0.3, 0.4, and 0.5 mg/L). According to the results, the 0.4 mg/L BL treatment had improved the plant height and leaf length after 30 days of treatment, which was displayed in an increase of 8.75% and 20.48%, respectively, when compared to the control (distilled water). On day 30, Z. schinifolium’s basal diameter, leaf breadth, compound leaf length, and leaf weight all rose noticeably after treatment with 0.4 mg/L BL. Furthermore, the 0.4 mg/L BL treatment raised the levels of osmotic substances (proline, soluble sugar, and soluble protein) and photosynthesis parameters (chlorophyll a, chlorophyll b, PSII, Fv/Fm, NPQ, and qP) in Z. schinifolium compared to the control. It also decreased the levels of malonaldehyde, increased the activities of antioxidant enzymes (POD, SOD, CAT, and APX), and increased the contents of non-enzymatic antioxidants (ASA and GSH). Accordingly, these findings implied that BL might be crucial in fostering Z. schinifolium growth and development by boosting antioxidant capacity, decreasing malonaldehyde concentration, preserving water balance, and improving photosynthesis.

Low-temperature stress is a major factor that limits the productivity and geographical distribution of melon (Cucumis melo L.). This study elucidates that CmDUF239-1 is a positive regulator of cold stress, and its underlying mechanisms are investigated using root-specific overexpression lines. Seedlings overexpressing CmDUF239-1 exhibited increased biomass and reduced relative electrical conductivity under cold stress. CmDUF239-1 overexpression promoted the accumulation of soluble sugar and proline, which was accompanied by enhanced activity of the proline biosynthetic enzyme Δ¹-pyrroline-5-carboxylate synthase (P5CS) and suppressed activity of the proline-degrading enzyme proline dehydrogenase (PDH). Molecular analysis revealed that CmDUF239-1 overexpression upregulated antioxidant enzyme-related genes, sugar metabolism related genes, and proline-related genes. Furthermore, it activated key genes in the ICE-CBF-COR signaling pathway, including CmCBF1, CmCBF2, and the downstream effector gene CmCOR413-2. In conclusion, the CmDUF239-1 gene enhances melon cold tolerance by modulating antioxidant defense, enhancing osmolyte (sugar and proline) metabolism and activating a core signaling pathway. This study not only characterizes a novel function for a DUF family gene but also provides a promising candidate gene for the genetic improvement of cold resilience in melon and other related crops.