Investigating the effect of different sodium chloride concentration nutrient media on the growth of some spinach (spinacia oleracea L.) varieties under ın vitro conditions

Salinity is a major abiotic stress factor that limits the growth and yield of crops, including spinach. This study aimed to investigate the effects of different NaCl concentrations (0, 100, 200, and 300 mM) on the germination, growth, and physiological responses of two spinach varieties Yaman (1) and Matador (2) under in vitro conditions. During the study; germination rate, stem fresh and dry weights (g), root fresh and dry weights (g), stem and root lengths (mm) parameters were evaluated. The results showed that all measured traits were significantly affected by salinity with differences observed among cultivars and media. The highest germination rate (75.50%) was recorded in variety 1, while the highest medium average was observed in the control treatment (TA, 75.00%). Increasing salinity levels, especially at 300 mM NaCl, led to a reduction in both stem and root biomass. The highest stem fresh weight (0.180 g) and root fresh weight (0.113 g) were obtained from the control medium (TA). Similarly, root dry weight and stem length showed significant decreases with increasing NaCl concentrations. Variety 2 showed comparatively greater tolerance under saline conditions, especially in terms of root biomass and lenght.