Effect of irrigation and fertilisation on the biologically active components of tomato

A three-year (2016–2018) open field experiment was conducted to study the effect of irrigation, fertilisation, and seasonal variation on the main bioactive components, such as carotenoids (lycopene and β-carotene), total polyphenols, antioxidant capacity, and tocopherols of processed Uno Rosso F1 tomato. The statistical evaluation of measurements proved that the multi-year data set cannot be evaluated as combined data set; the values obtained in different years must be evaluated separately. The impact of irrigation on the content of bioactive components varied from year to year. The correlation was negative between irrigation and α-tocopherol content in 2016 and 2018 (r = –0.567 and –0.605, respectively), polyphenol content in 2016 (r = –0.668), γ-tocopherol content in 2017 (r = –0.662), while positive correlation was observed between concentration of vitamin C (r = 0.533) in 2017, lycopene content (r = 0.473) in 2018 and irrigation intensity. A weak correlation was proved between K levels and concentrations of lycopene and polyphenols in 2016 (r = 0.301 and r = 0.392, respectively).