González-Villagra Jorge, Reyes-Díaz Marjorie M, Tighe-Neira Ricardo, Inostroza-Blancheteau Claudio, Escobar Ana Luengo, Bravo León A
Departamento de Ciencias Agropecuarias y Acuícolas, Facultad de Recursos Naturales, Universidad Católica de Temuco, Temuco 4781312, Chile.
Núcleo de Investigación en Producción Alimentaria, Facultad de Recursos Naturales, Universidad Católica de Temuco, Temuco 4781312, Chile.
Plants (Basel). 2022 Feb 26;11(5):639. doi: 10.3390/plants11050639.
Salicylic acid (SA) has been shown to ameliorate drought stress. However, physiological and biochemical mechanisms involved in drought stress tolerance induced by SA in plants have not been well understood. Thus, this study aimed to study the role of SA application on enzymatic and non-enzymatic antioxidants, photosynthetic performance, and plant growth in plants subjected to moderate drought stress. One-year-old plants were subjected to 100% and 60% of field capacity. When plants reached moderate drought stress (average of stem water potential of -1.0 MPa, considered as moderate drought stress), a single SA application was performed on plants. Then, physiological and biochemical features were determined at different times during 14 days. Our study showed that SA application increased 13.5% plant growth and recovered 41.9% and 40.7% in drought-stressed plants on day 3 compared to drought-stressed plants without SA application. Interestingly, SOD and APX activities were increased 85% and 60%, respectively, in drought-stressed SA-treated plants on day 3. Likewise, SA improved 30% total phenolic content and 60% antioxidant capacity in drought-stressed plants. Our study provides insight into the SA mechanism to tolerate moderate drought stress in plants.
水杨酸（SA）已被证明可缓解干旱胁迫。然而，SA诱导植物耐旱性所涉及的生理生化机制尚未得到充分了解。因此，本研究旨在探讨SA处理对中度干旱胁迫下植物的酶促和非酶促抗氧化剂、光合性能及植物生长的作用。对一年生植物进行田间持水量100%和60%的处理。当植物达到中度干旱胁迫（茎水势平均为-1.0 MPa，视为中度干旱胁迫）时，对植物进行单次SA处理。然后，在14天内的不同时间测定生理生化特征。我们的研究表明，与未施用SA的干旱胁迫植物相比；施用SA使植物生长增加了13.5%，并在第3天使干旱胁迫植物的恢复率分别达到41.9%和40.7%。有趣的是，在第3天，干旱胁迫下经SA处理的植物中，超氧化物歧化酶（SOD）和抗坏血酸过氧化物酶（APX）的活性分别提高了85%和60%。同样，SA使干旱胁迫植物的总酚含量提高了30%，抗氧化能力提高了60%。我们的研究为SA耐受植物中度干旱胁迫的机制提供了见解。
