Effect of ammonium fertilizer on growth and quality of Cichorium spinosum plants

In the present study, the effect of ammonium fertilizer rate on plant growth and quality of Cichorium spinosum L. was examined. Five fertilizer treatments were applied regarding the ammonium nitrogen percentage of total nitrogen, namely (1) 14%, (2) 24%, (3) 34%, (4) 43%, and (5) 53% of total nitrogen applied in the form of ammonium nitrogen. All the treatments received the same total nitrogen rate. Seeds of C. spinosum were sown in seed trays containing peat, and young seedlings were transplanted in 2L pots containing peat and perlite in a ratio 1:1. Plants were harvested twice during growing period and when rosettes reached the marketable size. On the harvest days, plant features regarding plant development (the number of leaves, the fresh and dry weight of leaves, and rosette diameter), as well as quality mineral composition, SPAD index of leaves) were recorded. From the results it is suggested that fertilizer composition had a significant effect on plant growth and quality. In particular, fresh weight for both harvests, as well total fresh weight were higher in treatments 4 and 5, where 43 and 53% of the total nitrogen was applied as ammonium nitrogen. Dry weight did not differ significantly in the first harvest, while in the second harvest treatment 1 had the lowest dry weight. Diameter and number of leaves were the lowest in treatments 2 and 3, respectively, while significant differences were also observed between treatments regarding the quality features.