IMPROVEMENT OF YIELD AND PHYTOCHEMICAL COMPOUNDS OF Thymus vulgaris THROUGH FOLIAR APPLICATION OF SALICYLIC ACID UNDER WATER STRESS

Abstract

Thymus vulgaris is an important medicinal plant across the world that has been grown in Iran since ancient times. To study the effect of foliar application of salicylic acid (SA) on the yield and phytochemical compositions of T. vulgaris, an experiment was conducted in Qazvin in 2017. A factorial experiment based on a randomised complete block design was conducted with three replications. Treatments of SA (0, 100, 150 and 200 mg/L) were applied from the period before flowering until the early stages of flowering under well-watered and withholding irrigation conditions. The results showed that SA had a significant effect on the yield and phytochemical compositions of T. vulgaris under both irrigation regimes. SA foliar application led to an increase in total dry matter. The highest total dry matter (1958.83 kg ha-1) was obtained by applying 200 mg/LSA under normal irrigation. The effect of foliar application of SA on the essential oil content of T. vulgaris was influenced by the irrigation regime. The highest essential oil content (2.66%) was obtained by applying a foliar spray of 100 mg/LSA under withholding irrigation conditions. Thymol, carvacrol, p-cymene, linalool and γ-terpinene were identified as the main essential oil compounds. The highest thymol content was obtained by foliar application of 200 mg/LSA under withholding irrigation conditions. Our results demonstrate that foliar application of SA reduced the negative effect of water deficit on T. vulgaris and increased yield and thymol content. SA foliar application is a simple, eco-friendly and relatively commercially viable method of increasing yield and the synthesis of phytochemicals; therefore, it may be used to improve the dry matter and quality of the essential oils of thyme plants.

Elicitor-Mediated Response of Growth, Yield, and Quality of Kalmegh (Andrographis paniculata Wall. ex Nees, Family Acanthaceae)

“…Our findings of increments in air-dry matter by chitosan application were in line with Ahmed et al [84], Bistgani et al [85], Thengumpally [53], and Ashwini [54]. Jayalakshmi et al [86], Bekheta and Iman [87], Mahammad [88], Bhasker et al [55], Mohammadi et al [89], and Priya [90] compiled the results on dry matter and their interdependence on salicylic acid.…”

Effect of Jasmonic Acid and Salicylic Acid on Growth and Biochemical Composition of In-Vitro-Propagated Lavandula angustifolia Mill

“…SA is widely distributed throughout the plant kingdom [31] and can influence a large number of physiological processes such as seed germination, thermogenesis, plant signaling or plant defense, and response to biotic and abiotic stress [32,33]. It has been proposed that exogenously-applied SA could reduce drought stress impact on plants [34]. Various levels of SA have been shown to protect the buds of Vitis genotypes during cryopreservation [35] and to stimulate flowering in Eleusine coracana L. [36] and fruit development in Fragaria x ananassa Duch.…”

Foliar Spray of Salicylic Acid Improved Yield Parameters and Essential Oil Production of Dill Under Water Deficit

“…Most of them can be used as herbicide and pesticide (Yamada et al, 2019). Plant Secondary metabolites are increasingly important factors in plant diversity and evolution (Mohammadi et al, 2020). Essential oils are important secondary metabolites that are used worldwide to produce perfumes, cosmetics, drinks, medicines, fungicides, and insecticides (Chouhan et al, 2017).…”