Akademik Veri Yönetim Sistemi
Journal of Plant Growth Regulation, 2024 (SCI-Expanded)
Cadmium (Cd) is a highly phytotoxic metal capable of directly or indirectly altering the structural and functional properties of plants, even at low concentrations. Melatonin (MEL), a hormone found naturally in plants, appears to offer potential benefits as a stress reducer agent and growth enhancer. However, although numerous studies have examined the effect of external or foliar applications of MEL on different morpho-physiological and biochemical parameters during long- or short-term heavy metal stress and subsequent recovery, studies involving seed priming with MEL are scarce. This study aimed to investigate whether MEL priming (prMEL, 50 µM) of buckwheat (Fagopyrum esculentum Moench 'Güneş') seeds can enhance seedling tolerance to Cd stress (0.5 and 1 ppm). Basic growth parameters, macro- and micronutrient concentrations, osmotic potential with various osmolytes, cell wall phenolic acids, lignin, and cell wall peroxidases were investigated in root, stem and leaf in the seedlings. The results showed that, compared to controls, Cd stress suppressed plant growth (ave. 33%), and osmotic potential (ave. 25%), increased osmolyte contents (ave. 40%), and enhanced cell wall phenolic acid contents (ave. 99%), lignin accumulation (ave. 64%), and cell wall peroxidases. However, prMEL application improved the growth parameters (ave. 24%), and reduced cell wall phenolic acid contents (ave. 32%) and lignin accumulation (ave. 23%) in comparison to stressed plants. However, osmotic potential (ave. 16%) and osmolyte contents (ave. 34%) increased only in the Cd1+MEL groups. Additionally, macro- and micronutrient concentrations varied depending on mineral transport properties and interacted with Cd and MEL priming. Our results indicate that MEL priming of dry seed improves lignification, maintains osmolite homeostasis, and provides a balanced mineral uptake, alleviating the adverse effects of Cd stress in buckwheat seedlings.