Effects of seed coating and priming with exogenous brassinosteroid on tobacco seed germination

Brassinosteroid (BR) is a hormone known for its crucial role in seed germination promotion. However, there is a limited understanding of potential application in tobacco seed. In this study, we investigated various active ingredients for seed coating to enhance tobacco seed germination. It revealed that seed coating with 0.0500 ppm BR and priming with 0.01 ppm BR significantly increased seed germination rates, especially in low-temperature conditions. In addition, the combined use BR with priming and seed coating exhibited a substantial improvement in seed germination rates and promoted seedling growth. Through transcriptional analysis, it found that BR treatment regulates the expression of genes associated with DNA synthesis, cell wall organization and glucan metabolic process involved in seed dormancy and seedling growth. Overall, these results provide valuable insights into the utilization of seed coating and priming techniques, particularly with the inclusion of BR, to enhance tobacco seed germination and facilitate seedling emergence.

油菜素甾醇（Brassinosteroid，BR）是一类因在促进种子萌发中发挥关键作用而被广泛认知的植物激素。然而，目前学界对其在烟草种子中的潜在应用价值尚缺乏充分探究。本研究针对可提升烟草种子萌发性能的种子包衣活性成分展开系统研究。结果显示，采用0.0500 ppm BR进行种子包衣、以0.01 ppm BR进行种子引发，均可显著提升烟草种子的萌发率，在低温胁迫环境下该效果尤为显著。此外，将BR联合应用于种子引发与种子包衣处理，可进一步大幅提升种子萌发率并促进幼苗生长。通过转录组分析发现，BR处理可调控与DNA合成、细胞壁构建及葡聚糖代谢相关的基因表达，而这些过程均参与种子休眠解除与幼苗生长调控。综上，本研究结果为利用BR结合种子包衣与引发技术提升烟草种子萌发效率、促进幼苗出土提供了重要的理论参考与实践依据。