کنگره بین المللی زیست فناوری گیاهان دارویی و قارچ های کوهی

صفحه اصلی / پنجمین کنگره بین المللی و ششمین همایش ملی زیست فناوری گیاهان دارویی و قارچ های کوهی

Combined Influence of Phosphorus Stress and Gibberellic Acid on the Secondary Metabolites of Mentha longifolia L.

نویسندگان :

Mahsa Rafati Alashti¹ Saedeh Rashidy²

1- Payame Noor University 2- Payame Noor University

کلمات کلیدی :

Antioxidant compounds،Monoterpenes،Nutrient deficiency،Secondary metabolism،Terpenoid biosynthesis

چکیده :

This study was conducted to evaluate the individual and interactive effects of phosphorus (P) stress and gibberellic acid (GA) application on the phytochemical composition of essential oil in Mentha longifolia L. The experiment was carried out under pot conditions in an open field using a randomized complete block design with four replications. Treatments included four P levels (100%, 75%, 50%, and 25% of the recommended P fertilizer rate) and two foliar spray regimes (with or without 100 mg L⁻¹ GA), arranged factorially. Aerial parts were harvested at full flowering, and essential oil constituents were extracted via hydro-distillation and analyzed by GC-MS. Results revealed that both P stress and GA significantly influenced the accumulation of key phytochemicals. Phosphorus deficiency generally increased monoterpene ketones, menthone, menthol, and pulegone, while decreasing oxygenated compounds such as 1,8-cineole and piperitenone oxide. GA application suppressed menthone and linalool but enhanced menthol and piperitenone oxide. Significant interaction effects (P < 0.01) were observed for several compounds, including α-pinene, limonene, linalool, menthol, terpinen-4-ol, α-terpineol, piperitone, thymol, and piperitenone oxide, indicating that the response to GA was modulated by P availability. For instance, thymol accumulation was promoted by GA under P sufficiency but induced only under severe P stress (25% P) in the absence of GA. Correlation analysis further revealed strong positive associations among piperitenone, piperitenone oxide, and terpinen-4-ol, and negative links between menthone and β-pinene derivatives, suggesting coordinated or competing biosynthetic pathways. These findings demonstrate that the phytochemical profile of M. longifolia is highly responsive to combined hormonal and nutritional signals, highlighting the potential for integrated P and GA management to tailor essential oil composition for specific industrial or medicinal applications.