Effects of foliar application of methanol on some physiological characteristics of Lavandula stoechas L. under NaCl salinity conditions

Abstract

In order to study the effects of foliar applications of methanol (0, 15, and 30%) and NaCl salinity (0, 50, and 100 mM) on some physiological characteristics of Lavandula stoechas L. plants, a pot experiment was carried out at the Research Greenhouse of Azarbaijan Shahid Madani University. Physiological characteristics (stem and leaf dry weights, total phenolic and flavonoids compounds, chlorophyll a and K⁺ contents, and K⁺/Na⁺ ratio) were significantly affected by the interaction effects of Methanol foliar application and salinity levels. The highest K⁺ content, K⁺/Na⁺ ratio, chl a and stem dry weight, belonged to NaCl 0 × Methanol 30% and NaCl 50 × Methanol 30%. For the leaves’ dry weight, the greatest data were recorded for NaCl 0 × Methanol 30% and NaCl 0 × methanol 15%. Methanol spray promoted the total phenolic content, especially at NaCl 50 × methanol 30% and NaCl 100 × methanol 15% and 30% and flavonoid content at NaCl 50 × methanol 30%. Anthocyanin content, essential oil percent, and flower dry weight were affected by NaCl salinity levels, and the highest amount of anthocyanin was recorded for the control treatment. The highest data for Essential oil was attained by the NaCl 0 and 50 mM. The Na⁺ content was affected by methanol foliar application and the highest amount was obtained in the control treatment. Both foliar application levels and salinity levels influenced the flower dry weight. The highest amount of the flower dry weight was recorded at 30% methanol spray level and 0 mM NaCl treatments. The results reveal that methanol application had significant effects on the physiological characteristics of Lavandula plants growing under salinity stress condition.

Keywords:

• Lavandula stoechas L. medicinal plant
• essential oil
• methanol
• phenolic compound