The polyphenolic compounds of several plant products are not known, nor are the biotic and abiotic factors that influence their evaluation.
Thus we have very few data about the effects of growing factors in case of root vegetables – for example soil type, light intensity, growing
method (on open field, under glass, in soil or without soil cultivation). Our experiment were aimed to prove the effects of genotypes and
growing method (direction of rows) on the enrichment of polyphenol, flavonoid and vitamin C content. In the experiments it was
established that varieties reacted differently on to the incidence of light originated from the direction of rows. Polyphenol, flavonoid and
dry material content of Prágai óriás were higher at North-South row directions, which originated from the favourable light luminous
influence without fail. Variety Neon produced better results in nutritional values of leaves at South West row directions. The opposite was
found for the polyphenol, flavonoid and dry matter contents of tubers. In this direction the sunshine from South warmed up the bed in
which the tubers were developing. This factor was favourable for their production. The results of our experiments showed differences
between the genotypes regarding their sensitivity, that is, the intensity of light that differed in the rows of different direction influenced the
formation of secondary metabolites. Results proved that celery leaves contain more bioactive compounds (total polyphenols, flavonoids,
vitamin C) than tubers. The difference in polyphenol content was threefold and six fold in flavonoid content. Vitamin C content in the
tubers was 30 percent of the amount that was measured in leaves at very similar dry material content. Our data document the nutritional
importance of celery leaves and emphasize the selection of the growing method to the needs of varieties to produce good quality vegetables
for our foods.
Key words: celery, bioactive compounds, leaves, tuber, polyphenols, flavonoids, vitamin C, growing method, row direction
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