The effect of salicylic acid and jasmonic acid solution spray on soluble sugar, proline and enzymes of lavender (Lavendula officinalis L.) under salt stress

Today medicinal plants are an important part of the traditional medicine in many countries, they also have a special place and high value in new therapeutic approaches. Iran is one of the major habitats of many medicinal plants, one of these medicinal herbs, lavender with the scientific name (Lavendula officinalis L.) is an evergreen plant from Lamiaceae family. Lavender belongs to arid and semi-arid areas. It needs lots of light, warm weather and less humidity during growth. Under such conditions, the performance of the flower, essence, as well as the quality of the essence increases. Salinity is the presence of soluble salts and mineral elements in water and soil that will lead to the salt accumulation in the root area so that the plant will face difficulty absorbing enough water from the soil solution. Soil salinity is one of the most important factors limiting crop yields around the world, that this issue, particularly in arid and semi-arid areas is considered as one of the most fundamental problems of agricultural sector. Iran, with warm and dry climate is no exception to this issue. More than half of its arable lands (around 27 million hectares) is formed from salty soil and sodium. So in order to make the optimal use of these lands and saline water resources, a reformative important approach is to boost plant tolerance associated with higher production capacity. To deal with the stress, plants have a defense system with high efficiency which can destroy or neutralize free radicals. This defense system, includes enzymatic and non-enzymatic mechanisms. according to the above mentioned items, this study was done to investigate the effect of salicylic acid and Jasmonic acid on the soluble sugars, Proline, activity of antioxidant enzyme of lavender herb (Lavendula officinalis L.), in salinity tension situation to reduce the bad effects of tension.
To investigate the effect of Salicylic acid and Jasmonic acid solution on soluble sugar, Proline and antioxidant enzyme activity of lavender herb in salt tension situation, the pot experiments was done in 1393 in Azad Islamic University, Yadegar Imam Khomeini (RAH) branch of Ray city also the greenhouses that located in strict 4. The experiment was done through a factorial arrangement in a completely randomized basis with four replications. The experimental factors were included salt stress from salt (NaCl) in four levels (0, 25, 50 and 75 mM), Salicylic acid in two levels (0 and 0.7 mM), and Jasmunic acid in two levels (0 and 100 mM).
The results of the comparison of the salinity average simple effects showed that this factor caused an increase in soluble sugar, proline, activity of antioxidant enzymes such as Catalase, Superoxide dismutase, Peroxidase, Ascorbate peroxidase and Glutathione peroxidase. According to the research, the use of Salicylic acid, Jasmonic acid through increasing the activity of soluble sugar and proline, increased plant resistance in saline conditions. The results of the study also showed that only the interaction of the three attributes of treatments of the experiment on Peroxidase, Ascorbate peroxidase’s traits was significant. In this case, the highest Peroxidase activity (50/27 mg pr/min) and ascorbate peroxidase (24/12 mg pr/min), in salinity factor 75 mM and the absence of the two mentioned compounds was obtained.
According to the results of the experiment, it can be confirmed that following the use of Salicylic acid and Jasmonic acid under salt stress, proline and soluble sugars contents were increased and antioxidant enzyme activities were decreased. In other words, while using these two compounds, the lavender medicinal herb has used soluble sugar and Proline to cope with the salt stress.