Investigating the effect of low water stress on Aromatic Geranium (Pelargonium graveolens) Morphophysiological traits and enzyme activity with Proline and Glutamine foliar application

Aromatic geranium is an ornamental plant whose essential oil is widely used in perfumery, health and cosmetic, food and pharmaceutical industries. In order to investigate the reduction of the adverse effects of low water stress in Aromatic Geranium (Pelargonium graveolens) plants by proline and glutamine foliar application, a factorial experiment was conducted based on a completely randomized design with ۳ replications in a commercial greenhouse located in Garmsar city in ۱۴۰۲-۱۴۰۳. The experiment was done in pots with ۳ levels of low water stress (۳۰, ۷۰ and ۱۰۰% of field capacity) and spraying with proline and glutamine (each with two levels of ۵۰ and ۱۰۰ mg/liter) and their interaction. Low water stress was applied after the plant’s establishment and in the ۶ to ۸ leaf stage. Foliar spraying with proline and glutamine at different levels was done in two stages. Finally, sampling and evaluation of traits was done about two weeks after the last spraying. The results showed that the highest fresh and dry weight of shoots (۷۱.۴۲ and ۹.۱۲ g), petals anthocyanin and total leaf chlorophyll (۳.۲۷۶۱ and ۱۶.۴۲۱۷ mg/g FW) and the lowest ionic leakage of the cell membrane (۵۴.۲۷%) were in glutamine ۱۰۰ mg/L at ۱۰۰% FC treatment. The highest root fresh and dry weight (۱۶.۳۵ and ۳.۶۷ g), the longest root length (۴۵.۲۸ cm), catalase, superoxide dismutase and peroxidase enzyme activity (۸.۲۳, ۳.۲۸ and ۱۷.۴۲ U E/g FW) and lowest proline amount was obtained in proline ۱۰۰ mg/liter at ۱۰۰% FC treatment. The longest shelf life of aromatic geranium flower on plant was (۱۴ days) in glutamine ۱۰۰ mg/liter at ۱۰۰% FC treatment and the lowest (۸ days) in control treatment at ۳۰% FC. In total, proline and glutamine with regulating osmotic pressure, inhibiting oxygen free radicals, and preventing membrane proteins and phospholipid degradation, caused a reduction low water stress negative effects in foliar-sprayed plants compared to the control in ۷۰ and ۳۰% FC. Therefore, it is possible to recommend proline and glutamine foliar application under low water stress conditions to improve aromatic geranium (Pelargonium graveolens) growth, quality and flowering.

کلیدواژه ها:

Catalase ، Glutamine ، Pelargonium graveolens ، Peroxidase ، Proline ، Superoxide dismutase ، پراکسیداز ، پرولین ، سوپراکسید دیسموتاز ، شمعدانی معطر ، کاتالاز ، گلوتامین