Herbal
Nastaran Rashidi; Ramazan Ali Khavarinejad; Parvin Ramak; Sara Saadatmand
Abstract
Introduction: Chitosan is a polysaccharide that elicits numerous defense responses in plants and affects the growth rate and increasing the production of secondary metabolites. Basil (Ocimum basilicum L.), a medical herb, has many varieties in terms of morphology and secondary compounds. Considering ...
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Introduction: Chitosan is a polysaccharide that elicits numerous defense responses in plants and affects the growth rate and increasing the production of secondary metabolites. Basil (Ocimum basilicum L.), a medical herb, has many varieties in terms of morphology and secondary compounds. Considering the growing trend of salinity and the its risks and the importance of basil in the pharmaceutical and food industries, this study was conducted to investigate the role of chitosan on some physiological and biochemical properties and Phenylalanine ammonia lyase (PAL) enzyme in basil under salinity stress.Methods: After chitosan treatments at a concentration of 200 mg/L, plants were exposed to four levels of NaCl salinity stress, 25, 50, 100 and 150 mM. The activity of PAL enzyme, physiological and biochemical responses were investigated under the effect of the interaction between chitosan and concentrations of salinity stress. Results and discussion: The salinity stress has negative effects on total chlorophyll and carotenoid whereas it increased flavonoid content. In addition, chitosan at high salinity levels had a positive effect on total chlorophyll, and at all salinity levels increased carotenoids content. Catalase and peroxidase enzymes and potassium content of basil also increased in chitosan treatments, which indicates an increase defense response to salinity in plant. Chitosan also increased PAL enzyme activity, as an important parameter in the biosynthesis of phenylpropanoids, which it increased the amount of methyl cavicol of essential oil. In general, the application of chitosan has an effect on the secondary compounds in basil to improve salt-stress tolerance.
