Copper modulates the biochemical and enzymatic activity and growth of tomato cultivars grown in vitro
¹Paranaense University – UNIPAR, Graduate Program in Biotechnology Applied to Agriculture, 87502-210, Umuarama, Paraná, Brazil
²Paranaense University – UNIPAR, Agronomy, 87502-210, Umuarama, Paraná, Brazil
Copper (Cu) is a micronutrient that is neglected for tomato growth. This study sought to identify the effects of exposure to Cu on the growth and biochemical activity of two tomato cultivars. Tomato seeds of ‘Carolina’ and ‘Cereja’ cultivars were disinfected and inoculated in MS medium plus copper sulfate concentrations (CuSO4) (default MS, 25, 50, and 100 μm) and had their growth monitored for 30 days. It was estimated that the growth and biomass accumulation of tomato plants ‘Carolina’ and ‘Cereja’, both from the aerial part and the roots, were benefited by 25 e 50 μm of CuSO4. However, it was observed that these concentrations were inefficient in controlling hyperhydricity and leaf deformation. There was a reduction of these phenomena in the treatment with 100 μm, in both cultivars. Tomato of ‘Carolina’ cultivar subjected to 100 μm showed an increase in anthocyanins and superoxide dismutase (SOD) activity in the root system. There was a reduction of catalase (CAT) activity in shoots exposed to Cu. ‘Cereja’ tomatoes subjected to 100 μm showed an increase in CAT and SOD activity in shoots and roots, respectively. It was concluded that the ‘Carolina’ and ‘Cereja’ tomatoes have their growth impaired when exposed to 100 μm CuSO4. Concentrations higher than 50 μm of CuSO4 cause an increase in the antioxidant activity in the shoot of tomato plants from the ‘Carolina’ cultivar. Concentrations higher than 50 μm CuSO4 increase SOD activity in the root system of tomato plants from the ‘Cereja’ cultivar.