Despite of plant mineral nutrition being a well-studied topic, organic-bound nitrogen has only recently attracted more attention as a part of plant N nutrition for sustainable agriculture. The aim of our study was to find out how protein casein as a sole N source affected photosynthetic performance and stress level of tobacco grown in vitro.
Casein-supplied plants showed a significantly lower performance index, which characterizes the function of the whole electron transport. In order to determine the level of stress caused by casein as a N source, we measured the content of phenolic compounds, reactive forms of oxygen and the activity of superoxide dismutase.