Unveiling Si’s shield: A holistic examination of Cd stress alleviation in maize through physiological and transcriptomic insights

作者：Tingting An, Yamin Gao, Qiqiang Kuang, Shuo Liu, Yuehui Chao, Bede S. Mickan, Yi Zhang, Bingcheng Xu, Suiqi Zhang, Min Yu, Yinglong Chen · 发表于：Environmental and Experimental Botany · 年份：2023 · DOI：10.1016/j.envexpbot.2023.105626 · 被引用次数：10 · 研究领域：Silicon Effects in Agriculture、Aluminum toxicity and tolerance in plants and animals、Geochemistry and Elemental Analysis

Cadmium (Cd), present in agricultural soil, poses a substantial threat to public health through the food chain, adversely affecting food crops and yield. This study examined the role of silicon (Si) in alleviating Cd stress in maize (Zea mays L.). Germinated uniform seedlings were transplanted into 20 L pots filled with a low-concentration nutrient solution. At the three fully expanded leaves stage (21 days after transplanting), plants were treated with Si (1000 μΜ as K2SO3) and Cd (10 μM as CdCl2). Plants were assessed 0, 1, and 28 days after treatments. The results demonstrate that Si application leads to a reduction in Cd concentration and content in maize shoot tissue. Additionally, Si treatment positively influences the activity of antioxidant enzymes (peroxidase, superoxidase dismutase, catalase) and plant hormones (abscisic acid, gibberellic acid, salicylic acid) in maize leaves. Furthermore, Si application enhances plant growth, increases levels of antioxidant substances, improves gas exchange parameters, boosts chlorophyll content, and enhances fluorescence. Weighted gene co-expression network analysis (WGCNA) and identification of transcription factors (TFs) and structural genes among differentially expressed genes (DEGs) reveal physiological correlations and enriched signaling pathways, particularly those related to metabolism and biosynthesis. Si actively modulates the formation of metabolites such as arginine and proline, starch and sucrose, as well as biosynthet...