The Function of Roots of Tea Plant (Camellia sinensis) Cultured by a Novel Form of Hydroponics and Soil Acidification

Kieko Saito, Masahiko Ikeda

College of Environment and Disaster Research, Fuji Tokoha University, Fuji, Japan.
Institute for Environmental Sciences, University of Shizuoka, Shizuoka, Japan.

DOI: 10.4236/ajps.2012.35078                

Abstract

A novel form of hydroponic culture was employed to explore the physiological function of roots of a tea plant (Camellia sinensis). The pH of the nutrient solution with an actively growing tea plant decreased during cultivation. Furthermore, no oxalic acid, tartaric acid, malic acid or citric acid, all possible factors in acidification, was detected in the nutrient solution of a growing plant. A proton pump inhibitor suppressed the acidification of the solution. Soil acidification might have been accelerated with a proton released from ammoniacal nitrogen preferentially for the growth, suggesting the specific mechanism of tea plant as a functional food.

Keywords

Acid Soil; Hydroponic Culture; Organic Acid; Tea; Root

Conflicts of Interest

The authors declare no conflicts of interest.

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