The Effect of Nitrogen and Sulphur Nutrition on the Yield and Content of Antioxidants in Broccoli / Vplyv Dusíkatej a Sírnatej Výživy na Úrodu a Obsah Antioxidantov v Brokolici

The small field experiment with broccoli (variety ‚Tiburon F1‘) was established in The Botanical Garden of Slovak University of Agriculture in Nitra. In this experiment, we investigated the effect of four variants of nutrition on the broccoli yield, content of sulforaphane and vitamin C in broccoli florets. The first variant of nutrition was a control one - without application of fertilizers. The second one was fertilized at nitrogen level 200 kg.ha^-1. The third one had level of nutriments N : S = 200 : 50 kg.ha^-1 and fourth one N : S = 200 : 60 kg.ha^-1. In each variant of nutrition, the yield of broccoli was significantly increased in comparison with the control variant. The highest yield of broccoli florets was reached in variant 4 (27.87 t.ha^-1). The highest amount of sulforaphane was also determined in variant 4 - 50.93 mg.kg^-1 of fresh matter. However, this value did not represent significant increase of sulforaphane content compared to the control variant. The highest content of vitamin C was determined in variant 2 (585.78 mg.kg^-1 of fresh matter). In this variant, we achieved significant increase of vitamin C content in comparison with the control variant. Thus, by application of nitrogen and sulphur nutrition, we reached significant increase of broccoli yield compared to the control variant. At the same time, the applied nutrition assisted to enhanced accumulation of sulforaphane and vitamin C in broccoli florets