Effect of priming using different combinations on germination indicators and antioxidant enzyme activity in Marigold seedling (Calendula officinalis) under salinity stress

In order to investigate the effect of priming on germination indicators and antioxidant enzyme activity in Marigold under salinity stress, a factorial experiment was conducted based on a completely randomized design with ۳ replications. Treatments were accelerated at four salinity levels (۰, ۵۰, ۱۰۰, and ۱۵۰ mM) and four priming levels (control (distilled water), priming with salicylic acid (۱۰۰ mg/L), gibberellin (۲۰ mg/L) and chitosan (۰.۸% weight volume, all of which had been dissolved in ۱% acetic acid). The results showed that the germination percentage (GP), seedling length (SL), Allometric Coefficient (CA) and Seedling weight vigor index (SWVI) decreased by ۲۱, ۳۷, ۱۷ and ۴۳% respectively compared to the salinity control, but priming with salicylic acid, gibberellin especially chitosan improved these traits. The lowest Daily Germination Speed (DGS) in priming with salicylic acid and gibberellin, especially priming with chitosan, and Mean Germination Time (MGT) were obtained in priming with chitosan and without salinity. The Germination rate (GR) and Seedling length vigor index (SLVI) in chitosan treatment and non-salinity compared to the control and ۱۵۰ mM salinity showed an increase respectively about ۷۵% and ۷۳%. The catalase (CAT) and superoxide dismutase (SOD) enzymes activity in priming with chitosan compared to the control (distilled water) showed an increase respectively of about ۱۸% and ۱۵%. Also, peroxidase (POX) enzyme activity in priming with chitosan and salinity of ۱۵۰ mM was about ۳۲% higher than the control (distilled water) and salinity of ۵۰ mM. The results showed that seed treatment with salicylic acid, gibberellin, especially chitosan by stimulating antioxidant enzymes and neutralizing free radicals can reduce the harmful effects of salinity stress on some traits in Marigold seedling and improve seedling growth. Therefore, since pot marigold seeds are generally weak and have low germination power, the application of ۰.۸% chitosan is a suitable option for improving germination and seedling growth of this plant.

Keywords:

Chitosan , Gibberellin , Priming , Marigold , Salicylic Acid , اسید سالیسیلیک , پرایمینگ , جیبرلین , کیتوزان , همیشه بهار