Abstract Though responses to Cd in rice (Oryza sativa L.) have been well established, there are few reports about the different effects of short-term exposure to Cd between the subspecies indica (‘Kasalath’ variety) and japonica (‘Nipponbare’ variety). We observed similar Cd accumulation and root damage in roots of two varieties under 6 h Cd stress, but KEGG pathway analysis of transcriptome data revealed that pathways involved in different metabolic processes were affected. Among them, antioxidant enzyme system was involved in Cd detoxification in ‘Nipponbare’ variety, whereas GSH metabolism played important roles in ‘Kasalath’ variety. From the results of physiological experiments, extremely higher activity of SOD, POD, and CAT was observed in ‘Nipponbare’ variety after a short-term exposure to Cd. At the same time, the immediate Cd-induced stimulation of Cys and PCs were observed in ‘Kasalath’ variety along with the enlargement of vacuoles. This study provides an overview of main responses to short-term Cd stress and identifies potential target genes that may contribute to the different mechanisms of Cd stress-resistance in roots of japonica subspecies and indica subspecies.

中文翻译：

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两个水稻品种对镉的短期反应的转录组学和生理学比较

摘要 虽然水稻 (Oryza sativa L.) 对 Cd 的反应已经很好地建立，但很少有关于短期接触 Cd 亚种籼 ('Kasalath' 品种) 和粳稻 ('Nipponbare' 品种) 之间不同影响的报道。 ）。我们在 6 小时 Cd 胁迫下观察到两个品种根部的 Cd 积累和根损伤相似，但转录组数据的 KEGG 通路分析显示参与不同代谢过程的通路受到影响。其中，抗氧化酶系统参与了'Nipponbare'品种的Cd解毒，而GSH代谢在'Kasalath'品种中起重要作用。从生理实验结果来看，在短期暴露于 Cd 后，'Nipponbare' 品种的 SOD、POD 和 CAT 的活性极高。同时，在 'Kasalath' 品种中观察到 Cd 诱导的 Cys 和 PCs 的直接刺激以及液泡的扩大。本研究概述了对短期镉胁迫的主要反应，并确定了可能有助于粳稻亚种和籼稻亚种根部抗镉胁迫不同机制的潜在靶基因。