Abstract

Thymbra spicata L. (Mediterranean thyme) belonging to the family Lamiaceae, is an important medicinal and aromatic plant. The effects of the foliar applications including control and salicylic acid (2.5 and 5.0 mM) and chitosan (0.5 and 1.0 g/L) under different soil moisture condition on the chemical compositions and yield of essential oil from T. spicata L. were investigated. The essential oil from the aerial parts of the herb was analyzed by GC-FID and GC/MS. The foliar spraying of salicylic acid and chitosan significantly improved essential oil yield (2.5-2.7 mL/100 g dry matter) from 30 % to 60 % compared with control (1.7 mL/100 g). In this study, five major compounds including carvacrol, as the predominant constituent of the essential oil (48.40-79.1 %), γ-terpinene (7.27-25.62 %), limonene (3.62-10.35 %), p-cymene (1.69-6.44 %) and β-caryophyllene (1-1.5 %) were identified in the T. spicata L. essential oil. The carvacrol contents in the essential oil increased in the plants spraying by salicylic acid and chitosan compared with control. The effects of foliar application ×soil moisture conditions significantly affected the essential oil; the highest percentage of carvacrol was obtained from salicylic acid (at 5.0 mM) × deficit water stress. In conclusion, the foliar applications of salicylic acid and chitosan could decrease the harmful effects of water deficit on the essential oil yield and the carvacrol concentration in the T. spicata essential oil.

摘要

百里香属Thymbra spicata L.（地中海百里香）属于唇形科，是一种重要的药用和芳香植物。在叶面施用的，包括来自不同土壤水分条件下的化学组合物控制和水杨酸（2.5和5.0毫摩尔）和壳聚糖（0.5和1.0g / L）和精油的产率的影响T.兰香对L.进行了调查。通过GC-FID和GC / MS分析了草本植物地上部分的精油。与对照（1.7 mL / 100 g）相比，水杨酸和壳聚糖的叶面喷洒可将精油收率（2.5-2.7 mL / 100 g干物质）从30％显着提高至60％。在这项研究中，五种主要化合物包括香芹酚，它们是精油的主要成分（48.40-79.1％），γ-萜品烯（7.27-25.62％），柠檬烯（3.62-10.35％），对-丁烯（1.69-6.44） ％）和β-石竹烯（1-1.5％）被鉴定为穗状花序L.精油。与对照相比，喷施水杨酸和壳聚糖的植物精油中香芹酚含量增加。叶面施肥的效果×土壤水分条件对精油有显着影响；最高的香芹酚含量是从水杨酸（5.0 mM）×缺水胁迫中获得的。总之，水杨酸和脱乙酰壳多糖的叶面施用能降低对精油产率和在所述香芹酚浓度水分亏缺的有害影响T.兰香精油。