Effect of gamma-aminobutyric acid and proline on morphological and phytochemical traits of Matricaria chamomilla L. under water defecit stress condition

Kheiry, Azizollah; Pouryusef, Fatemeh Mahya; Sanikhani, Mohsen

doi:10.30470/jmpb.2026.2072887.1154

Effect of gamma-aminobutyric acid and proline on morphological and phytochemical traits of Matricaria chamomilla L. under water defecit stress condition

Document Type : Original Article

Authors

Azizollah Kheiry ¹

Fatemeh Mahya Pouryusef ²

Mohsen Sanikhani ³

¹ Associate Professor, Department of Horticultural Sciences, Faculty of Agriculture, University of Zanjan-Iran.

² Master's student, Department of Horticultural Sciences, Faculty of Agriculture, University of Zanjan -Iran

³ Assistant Professor, Department of Horticultural Sciences, Faculty of Agriculture, University of Zanjan-Iran

10.30470/jmpb.2026.2072887.1154

Abstract

To investigate the effect of proline and gamma-aminobutyric acid on the quantitative and qualitative traits of medicinal plant chamomile (Matricaria chamomilla L.) under water deficit stress, an experiment was conducted according to split plots design with a completely randomized block arrangement with four replications during the spring and summer of 2024 in the research greenhouse at the University of Zanjan. The main factor consisted of two irrigation levels (70 and 100% of field capacity) and the subplots included foliar applications of two levels of proline (0.5 and 1 mM), gamma-aminobutyric acid (0.5 and 1 mM) and control treatment (distilled water).
The results showed that the highest chlorophyll a content (1.40 mg/g fresh weight) was achieved under 100% field capacity irrigation combined with 1 mM proline. Foliar application of 0.5 mM proline under 70% irrigation level resulted in the highest phenolic content (4.78 mg gallic acid/g dry weight) and the greatest total antioxidant activity (51.75%). The maximum flavonoid content (1.49 mg quercetin/g dry weight) was observed with 0.5 M GABA treatment. Additionally, the highest thousand-seed weight (148 mg) was recorded under full irrigation (100% field capacity) with 1 mM proline, compared to the control. Overall, the combined application of 0.5 mM proline and GABA was most effective in mitigating the adverse effects of drought stress on chamomile.

Keywords

Antioxidant

Droght Stress

Field Capacity

Flavonoid

Phenol

Subjects