Azizolah Khandan-Mirkohi; Mahdieh Khalili Halbi; Seyed Alireza Salami; Hosein Lesani
Abstract
To study effects of salicylic acid (SA) treatments (0, 0.5, 1 and 2 mM) in two forms of seed priming (for 24 h) and spraying on seedling at 4-6 leaf stage an experiment was conducted on periwinkle (Catharanthus roseus Don.) with and without exposure to a mild cold stress of 8 °C (for 32 h). Seeds ...
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To study effects of salicylic acid (SA) treatments (0, 0.5, 1 and 2 mM) in two forms of seed priming (for 24 h) and spraying on seedling at 4-6 leaf stage an experiment was conducted on periwinkle (Catharanthus roseus Don.) with and without exposure to a mild cold stress of 8 °C (for 32 h). Seeds were sown in trays containing peat-based substrate (with 20% sandy loam field soil). Transplants of both groups were treated with mild cold. Seedlings were grown in greenhouse with an average day/night temperature of 25/20± 2°C until their blooming. Seed emergence rate and percentage, activities of catalase (CAT), guaiacol peroxidase (GPX), polyphenol oxidase (PPO), CAT gene expression, height and number of nodes per plant, and days to flowering were evaluated. Results showed that mild cold stress together with salicylic acid at 0.5 mM (as either seed priming or spray on seedling) was the best treatment to accelerate the flowering, and improve growth parameters and antioxidant enzymatic activities. Thus, mild cold stress enhanced the positive effects of SA treatments on cold acclimation of periwinkle (particularly when associated with spraying, which is a simple administration method). Accordingly, it might be recommended for its seedling production and cultivation in temperate climates to prevent late spring frost damages.
Mohammad Hosein Shamshiri; Mohammad Reza Hasani
Abstract
This study was conducted to determine the combined effects of salicylic acid (SA) and arbuscular mycorrhizal fungi (AMF) (Glomus mosseae) symbiosis on the growth of pistachio seedlings (Pistacia vera ‘Abareqi’) grown in the greenhouse under different drought stress (DS) levels. The arbuscular ...
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This study was conducted to determine the combined effects of salicylic acid (SA) and arbuscular mycorrhizal fungi (AMF) (Glomus mosseae) symbiosis on the growth of pistachio seedlings (Pistacia vera ‘Abareqi’) grown in the greenhouse under different drought stress (DS) levels. The arbuscular mycorrhizal fungi (AMF) colonization or exogenous SA treatment could increase ‘Abareqi’ pistachio seedlings tolerance to DS. Application of SA on AMF-inoculated seedlings further promoted drought tolerance, as indicated by an alleviated plant biomass and water relations compared to the respective treatments. The analysis of proline and soluble carbohydrates showed that the increased drought tolerance in the treated plants may be associated, at least in part, with increasing of proline accumulation in the leaves of stressed plants.
