Abstract Salicylic acid (SA) is a phenolic phytohormone that acts in different physiological plant processes and is considered an efficient elicitor in the production of secondary metabolites, including essential oils. The effects of SA on biomass production, primary metabolites contents and nutrients in leaves of Achillea millefolium L. plants were evaluated. Additionally, the effect of SA on the quantity and quality of essential oil was evaluated. The experiments were carried out under field conditions in two consecutive seasons (2016 and 2017), with SA foliar applications at a dose of 1.0 mmol L-1 in different periods (20, 60 and 100 days after planting - DAP and at 100 DAP for three consecutive days) with water treated plants as control. Plants treated with SA showed higher dry weight values (leaf, root and total) and photosynthetic pigment contents. The positive effects of SA on the primary plant metabolism were evidenced by the higher concentrations of total sugars, proteins and amino acids in both application periods and years of cultivation. The levels of macronutrients in the leaves were also increased compared to the controls. SA applications resulted in higher content and yield of essential oil. The qualitative analysis of the essential oil showed the predominant presence of volatile compound chamazulene. Our results have demonstrated that the application of 1.0 mmol L-1 of SA at 100 DAP induced a series of coordinated metabolic changes that resulted in increases in yield and essential oil content in A. millefolium, which makes the aerial application of this elicitor a promising approach for its use in plants grown under field conditions.

中文翻译：

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水杨酸叶面喷施增加了千叶蓍草的生物量、养分同化、初级代谢产物和精油含量

摘要 水杨酸 (SA) 是一种酚类植物激素，在植物的不同生理过程中起作用，被认为是产生包括精油在内的次级代谢产物的有效诱导剂。评估了 SA 对 Achillea millefolium L. 植物叶片中生物量产生、初级代谢物含量和营养成分的影响。此外，还评估了 SA 对精油数量和质量的影响。试验是在连续两个季节（2016 年和 2017 年）的田间条件下进行的，在不同时期（种植后 20、60 和 100 天 - DAP 和 100 DAP）以 1.0 mmol L-1 的剂量喷洒 SA连续三天）以水处理植物作为对照。用 SA 处理的植物表现出更高的干重值（叶、根和总）和光合色素含量。SA 对主要植物代谢的积极影响通过在施用时期和栽培年限中较高浓度的总糖、蛋白质和氨基酸来证明。与对照相比，叶片中大量营养素的水平也有所增加。SA 应用导致更高的精油含量和产量。精油的定性分析表明主要存在挥发性化合物 chamazulen。我们的结果表明，在 100 DAP 下应用 1.0 mmol L-1 的 SA 诱导了一系列协调的代谢变化，导致 A. millefolium 的产量和精油含量增加，