Bilal Saqib, Khan Adil, Imran Muhammad, Khan Abdul Latif, Asaf Sajjad, Al-Rawahi Ahmed, Al-Azri Masoud Sulaiman Abood, Al-Harrasi Ahmed, Lee In-Jung
Natural & Medical Sciences Research Center, University of Nizwa, Nizwa 616, Oman.
Institute of Genomics for Crop Abiotic Stress Tolerance, Department of Plant and Soil Science, Texas Tech University, Lubbock, TX 79409, USA.
Antioxidants (Basel). 2022 May 27;11(6):1063. doi: 10.3390/antiox11061063.
The current study aimed to understand the synergistic impacts of silicon (Si; 1.0 mM) and boron (B; 10 µM) application on modulating physio-molecular responses of date palm to mitigate aluminum (Al; 2.0 mM) toxicity. Results revealed that compared to sole Si and B treatments, a combined application significantly improved plant growth, biomass, and photosynthetic pigments during Al toxicity. Interestingly, Si and B resulted in significantly higher exudation of organic acid (malic acids, citric acids, and acetic acid) in the plant's rhizosphere. This is also correlated with the reduced accumulation and translocation of Al in roots (60%) and shoots (56%) in Si and B treatments during Al toxicity compared to in sole Al treatment. The activation of organic acids by combined Si + B application has significantly regulated the , and plasma membrane ATPase; and in roots and shoots. Further, the Si-related transporter gene was upregulated by Si + B application under Al toxicity. This was also validated by the higher uptake and translocation of Si in plants. Al-induced oxidative stress was significantly counteracted by exhibiting lower malondialdehyde and superoxide production in Si + B treatments. Experiencing less oxidative stress was evident from upregulation of and expression; hence, enzymatic activities such as polyphenol oxidase, catalase, peroxidase, and ascorbate peroxidase were significantly activated. In the case of endogenous phytohormones, Si + B application demonstrated the downregulation of the abscisic acid (ABA; and and salicylic acid (SA; , ) biosynthesis-related genes. Consequently, we also noticed a lower accumulation of ABA and rising SA levels under Al-stress. The current findings illustrate that the synergistic Si + B application could be an effective strategy for date palm growth and productivity against Al stress and could be further extended in field trails in Al-contaminated fields.
当前研究旨在了解施用硅（Si；1.0 mM）和硼（B；10 µM）对调控枣椰树生理分子反应以减轻铝（Al；2.0 mM）毒性的协同影响。结果显示，与单独施用硅和硼的处理相比，在铝毒胁迫期间，联合施用显著促进了植株生长、生物量积累以及光合色素含量的增加。有趣的是，硅和硼使植物根际有机酸（苹果酸、柠檬酸和乙酸）的渗出量显著提高。这也与铝毒胁迫期间硅和硼处理组中根部（60%）和地上部（56%）铝的积累和转运量相比单独铝处理组减少有关。硅和硼联合施用激活有机酸显著调节了根部和地上部的 、 以及质膜ATP酶； 以及 。此外，在铝毒胁迫下，硅和硼联合施用使与硅相关的转运蛋白 基因上调。这也通过植物中硅的更高吸收和转运得到验证。硅和硼联合处理通过降低丙二醛和超氧化物的产生显著抵消了铝诱导的氧化应激。 和 表达上调表明氧化应激减轻，因此多酚氧化酶、过氧化氢酶、过氧化物酶和抗坏血酸过氧化物酶等酶活性显著激活。在内源植物激素方面，硅和硼联合施用使脱落酸（ABA； 和 ）和水杨酸（SA； ， ）生物合成相关基因下调。因此，我们还注意到在铝胁迫下ABA积累减少而SA水平升高。当前研究结果表明，硅和硼联合施用可能是一种有效的策略，可促进枣椰树在铝胁迫下的生长和生产力，并且可以在铝污染田间试验中进一步推广。
