Chemical composition and morphometric traits and yield of carrots grown in organic and integrated farming systems

Abstract

Changes in chemical composition and quality traits of carrot roots (Daucus carota L.) grown in organic (ORG) and integrated (INT) farming systems were investigated during two successive years. Three carrot cultivars (Fanal, Rodelika, and Rolanka) were included. Determinations of sugars, organic acids, α- and β-carotene, and vitamin C were performed with an HPLC system, and a liquid chromatography-mass spectrometry (LC-MS) system was used for the identification and quantification of phenolics. A higher yield of carrot in the ORG system was observed (42-44 t ha-1) as compared with the INT system (37-40 t ha-1). The impact of farming system on morphometric traits was cultivar-specific. The composition of sugars and carotenes was determined using compositional data analysis. The relative amount of sucrose against the combined amount of fructose and glucose was higher for roots from the ORG system compared to the INT system and for roots of Rodelika compared to Fanal. Roots from ORG farming contained 1.6-fold higher content of malic acid in Fanal and Rolanka and 2.4-fold in Rodelika compared to the INT system. Organic farming increased the content of vitamin C by 5% in roots of Rodelika, 15% in roots of Rolanka, and 22% in roots of Fanal compared to the INT farming. Changes in carotenes content in carrot roots were cultivar-specific with significantly higher α- and β-carotene contents in Rodelika and Rolanka compared to Fanal. Farming system influenced the ratio of β-car/α-car, which was higher for roots gathered from the INT system (1.9) compared to ORG system (1.7), but the differences were not significant. Phenolic acids detected in the study differed significantly in relation to cultivar as revealed by lower concentrations in the roots of Rodelika and Fanal compared with higher levels in the roots of Rolanka.