Gulzar Faiza, Yang Hongkun, Chen Jiabo, Hassan Beenish, Huang Xiulan, Qiong Fangao
State Key Laboratory of Crop Gene Exploration and Utilization in Southwest China, Ministry of Science and Technology, Chengdu 611130, China.
Rice Research Institute, Sichuan Agricultural University, Chengdu 611130, China.
Plants (Basel). 2024 Jul 21;13(14):1991. doi: 10.3390/plants13141991.
Waterlogging stress causes substantial destruction to plant growth and production under climatic fluctuations globally. Plants hormones have been widely explored in numerous crops, displaying an imperative role in crop defense and growth mechanism. However, there is a paucity of research on the subject of plant hormones regulating waterlogging stress responses in wheat crop. In this study, we clarified the role of 6-BA in waterlogging stress through inducing phenylpropanoid biosynthesis in wheat. The application of 6-BA (6-benzyladenine) enhanced the growth and development of wheat plants under waterlogging stress, which was accompanied by reduced electrolyte leakage, high chlorophyll, and soluble sugar content. ROS scavenging was also enhanced by 6-BA, resulting in reduced MDA and HO accumulation and amplified antioxidant enzyme activities. Additionally, under the effect of 6-BA, the acceleration of lignin content and accumulation in the cell walls of wheat tissues, along with the activation of PAL (phenylalanine ammonia lyase), TAL (tyrosine ammonia lyase), and 4CL (4-hydroxycinnamate CoA ligase) activities and the increase in the level of transcription of the and genes, were observed under waterlogging stress. Also, 6-BA improved the root growth system under waterlogging stress conditions. Further qPCR analysis revealed increased auxin signaling () in 6-BA-treated plants under waterlogging stress that was consistent with the induction of endogenous IAA hormone content under waterlogging stress conditions. Here, 6-BA also reduced yield loss, as compared to control plants. Thus, the obtained data suggested that, under the application of 6-BA, phenylpropanoid metabolism (i.e., lignin) was stimulated, playing a significant role in reducing the negative effects of waterlogging stress on yield, as evinced by the improved plant growth parameters.
在全球气候波动的情况下，涝渍胁迫对植物生长和产量造成了严重破坏。植物激素已在众多作物中得到广泛研究，在作物防御和生长机制中发挥着至关重要的作用。然而，关于植物激素调节小麦作物涝渍胁迫响应这一主题的研究却很少。在本研究中，我们通过诱导小麦中苯丙烷类生物合成，阐明了6-苄氨基腺嘌呤（6-BA）在涝渍胁迫中的作用。6-苄氨基腺嘌呤（6-BA）的施用促进了涝渍胁迫下小麦植株的生长发育，同时伴随着电解质渗漏减少、叶绿素和可溶性糖含量升高。6-苄氨基腺嘌呤（6-BA）还增强了活性氧清除能力，导致丙二醛（MDA）和过氧化氢（H₂O₂）积累减少，抗氧化酶活性增强。此外，在6-苄氨基腺嘌呤（6-BA）的作用下，观察到涝渍胁迫下小麦组织细胞壁中木质素含量增加和积累加速，同时苯丙氨酸解氨酶（PAL）、酪氨酸解氨酶（TAL）和4-香豆酸辅酶A连接酶（4CL）活性激活，以及相关基因转录水平提高。而且，6-苄氨基腺嘌呤（6-BA）改善了涝渍胁迫条件下的根系生长系统。进一步的定量聚合酶链反应（qPCR）分析表明，涝渍胁迫下经6-苄氨基腺嘌呤（6-BA）处理的植株中生长素信号转导相关基因表达增加，这与涝渍胁迫条件下内源吲哚-3-乙酸（IAA）激素含量的诱导一致。在此，与对照植株相比，6-苄氨基腺嘌呤（6-BA）还减少了产量损失。因此，所获得的数据表明，在6-苄氨基腺嘌呤（6-BA）的作用下，苯丙烷类代谢（即木质素）受到刺激，在减轻涝渍胁迫对产量的负面影响方面发挥了重要作用，这从改善的植物生长参数中得到了证明。
