Abstract
Histological analysis was employed to investigate the way potato plants (Solanum tuberosum cv. Draga and Spunta) face salinity stress. Different concentrations of NaCl (50, 100, 150, 200 and 250 mM) were used on potato plantlets growing in vitro to simulate salinity stress condition. Potato plants treated with 50 and 100 mM concentrations of NaCl went into the osmotic stage, and responded with changes: the flavone naringin was created and accumulated in the cells of the aerial parts, and a different type of trichome was observed, in addition to the original types, in potato plants treated with concentration 100 mM. This new type of trichome appeared similar to type B trichomes therefore they were called "type B-like trichomes". While no substance was exudated from these trichomes in cv. Draga, the trichomes, in cv. Spunta, green droplets were noted on the glandular vesicle. Furthermore, the non glandular trichomes had some swollen stem cells, and branched ones were also observed. Thanks to these new trichomes, the plants had increased leaf pubescence.