Abstract
The aim of the research was to explore the nutritionally important flavonoid concentrations in basil under two different aspects. In the first part, the investigation of the flavonoid concentration was carried out throughout leaf development at different leaf positions as well as other senescence related changes. Results indicate that there were significant reductions in both foliar mass and leaf area, and that flavonoid levels increased with the stage of maturity of basil leaves. The second foliar aging leaves significantly exhibited the highest values of flavonoids. In the second part, the influence of NaCl salinity on flavonoid concentration, second foliar leaf characters, physiological and biochemical parameters were studied. Saline stress adversely impacted plant growth and minerals of basil plants, and enhanced MDA concentration and electrolyte leakage, showing a significant and positive influence on flavonoids concentration. Accumulation of flavonoids played a key role in plant tolerance to NaCl.