The process of etiolation contributes significantly to vegetative propagation and root formation of woody plants. However, the molecular interaction pattern of different factors for etiolated adventitious root development in woody plants remains unclear. In the present study, we explored the changes at different etiolation stages of adventitious root formation in Robinia pseudoacacia. Histological and transcriptomic analyses were performed for the etiolated lower portion of hypocotyls to ascertain the adventitious root responses. We found that the dark-treated hypocotyls formed roots earlier than the control. Exogenous application of NAA (0.3 mg/L) stimulated the expressions of about 310 genes. Among these, 155 were upregulated and 155 were downregulated. Moreover, differentially expressed genes (DEGs) were significantly enriched in multiple pathways, including the biosynthesis of secondary metabolites, metabolic pathway, plant hormone signal transduction, starch and sucrose metabolism, phenylpropanoid biosynthesis, and carbon metabolism. These pathways could play a significant role during adventitious root formation in etiolated hypocotyls. The findings of this study can provide novel insights and a foundation for further studies to elucidate the connection between etiolation and adventitious root formation in woody plants.

中文翻译：

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转录组学和解剖学分析揭示黄化通过外源施用 1-萘乙酸在刺槐中促进不定生根。

黄化过程对木本植物的营养繁殖和根形成有显着贡献。然而，木本植物黄化不定根发育的不同因素的分子相互作用模式仍不清楚。在本研究中，我们探索在不定根形成的不同阶段的黄化的变化刺槐 刺槐. 对下胚轴的黄化下部进行组织学和转录组学分析，以确定不定根反应。我们发现暗处理的下胚轴比对照更早形成根。外源性应用 NAA (0.3 mg/L) 刺激了约 310 个基因的表达。其中，155个上调，155个下调。此外，差异表达基因（DEGs）在多种途径中显着富集，包括次级代谢产物的生物合成、代谢途径、植物激素信号转导、淀粉和蔗糖代谢、苯丙烷生物合成和碳代谢。这些途径可能在黄化下胚轴的不定根形成过程中发挥重要作用。