The Mechanisms Underlying Physiological and Molecular Responses to Waterlogging in Flax

ABSTRACT

Waterlogging due to excessive rainfall has become a factor limiting flax production in southern China. This has led to morphology alteration, and biomass and yield reduction in field crop production. Flax variety Zhongyama 1 was planted in sand culture, and the adaptive mechanisms of the responses to waterlogging in the fast growth and harvest stage were determined. According to the results, height and total biomass decreased significantly under waterlogged conditions during the fast growth period; furthermore, in the harvest stage, flax height increased significantly, whereas the technical length, fork diameter, and weight decreased significantly. For gene expression, the gene of glucose, glutathione metabolism, was up-regulated in shoot, and the gene of phenylpropanoid metabolic, lignin, was up-regulated in root. The results suggested that the synthesis and degradation of lignin is involved in flax resistance to waterlogging, especially in terms of phenylpropanoid biosynthesis, glycolysis, and metabolism of plant hormone signal transduction. Furthermore, unpaired electrons flowing through the electron transport chain may react with oxygen to produce ROS and hamper plant growth, development, and survival.

摘要

降雨过多导致的水涝已成为限制中国南方亚麻生产的一个重要因素。它导致了在亚麻田间生产中的形态变化, 以及生物量、产量下降。本研究通过砂培试验, 研究了中亚麻1号在快速生长期和收获期对水涝的适应性机制。研究发现, 水涝导致亚麻株高和总生物量在快速生长期显著下降; 亚麻株高在收获期显著增加, 而工艺长度、茎粗和生物量显著下降。在基因表达方面, 水涝处理下葡萄糖、谷胱甘肽代谢基因在地上部的表达量显著上调, 苯丙素代谢基因、木质素基因在根部的表达量显著上调。本研究的结果表明, 木质素的合成和降解与亚麻的耐涝性有关, 尤其是在苯丙烷生物合成、糖酵解和植物激素信号转导。此外, 流经电子传输链的未配对电子可能与氧气反应产生活性氧 (ROS), 从而阻碍亚麻的生长、发育和存活。

KEYWORDS:

• Flax
• waterlogging
• lignin synthesis and degradation
• phenylpropanoid biosynthesis
• resistant agriculture

关键词:

• 亚麻
• 水涝
• 木质素的合成和降解
• 苯丙素生物合成
• 抗性农业

Disclosure statement

No potential conflict of interest was reported by the authors.

Highlights

• Waterlogging markedly inhibited the growth of flax.

• Differentially expressed genes in flax are involved in shoot and root resistance to waterlogging.

• Waterlogging enhanced lignin synthesis and degradation efficiency in the flax root.

• Lignin synthesis and degradation may affect the resistance of flax to waterlogging, especially by regulating phenylpropanoid biosynthesis, glycolysis, and plant hormone metabolism.

Additional information

Funding

This work was supported by the earmarked fund for CARS-16; the National Natural Science Foundation of China (31401469); Central Public-interest Scientific Institution Basal Research Fund (No. 1610242023008); Agricultural Science and Technology Innovation Program (No. ASTIP-IBFC-04); Changsha Natural Science Foundation [kq2208248].