Acta Univ. Agric. Silvic. Mendelianae Brun. 2015, 63, 787-791

https://doi.org/10.11118/actaun201563030787
Published online 2015-06-28

What is More Suitable for Kohlrabi Fertilization – Digestate or Mineral Fertilizers

Tomáš Lošák1, Jaroslav Hlušek1, Hana Bělíková2, Monika Vítězová2, Tomáš Vítěz3, Jacek Antonkiewicz4

1Department of Environmentalistics and Natural Resources, Faculty of Regional Development and International Studies, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic
2Department of Agrochemistry, Soil Science, Microbiology and Plant Nutrition, Faculty of Agronomy, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic
3Department of Agricultural, Food and Environmental Engineering, Faculty of Agronomy, Mendel University in Brno, Zemědělská 1, 613 00 Brno, Czech Republic
4Department of Agricultural and Environmental Chemistry, University of Agriculture in Krakow, Al. Mickiewicza 21, 31-120 Krakow, Poland

In a one-year vegetation pot experiment, we compared the effect of digestate from a biogas station and mineral fertilisers on yield and quality parameters of kohlrabi, variety Moravia. Four treatments were used in the trial: 1) untreated control, 2) urea, 3) digestate, 4) urea, triple superphosphate, KCl, MgSO4. The N dose was the same in treatments 2–4, 1.5 g N/pot. In treatment 4 the P, K and Mg doses corresponded to those supplied in the digestate treatment (3).
The weight of single kohlrabi bulbs in the unfertilised control was significantly lower (39.2%) than in the urea treatment (100%) and the other fertilised treatments. After application of digestate (treatment 3) and mineral fertilisers (treatment 4), the weight of single bulbs significantly increased by 18.6 and 25.2%, respectively, compared with the urea treatment (2). The content of ascorbic acid did not differ among the all four treatments (274–291 mg/kg). There were significant differences between all fertilised treatments (2, 3, 4) in bulb nitrate content (792, 327, 776 mg NO3/kg fresh matter, respectively). The content of nitrates was the lowest in the unfertilised treatment – 135 mg NO3/kg fresh matter. After digestate application the nitrate content decreased significantly, to 327 mg NO3/kg fresh matter. We recommend the use of digestate to kohlrabi as it results in comparable or better yield and qualitative parameters of kohlrabi compared with mineral fertilizers.

Funding

This study was financed by the Internal Grant Agency of the Faculty of Agronomy MENDELU in Brno No. TP 8/2014.

References

33 live references