Chemical composition of breeding numbers of common chicory

Abstract

The aim and tasks of the study. To explore basic parameters of chemical composition of breeding numbers common chicory (Cichorium intybus L. var. sativum Lam) varying by dry matter content and total sugars and inulin content.

Material and methods. We experimentally examined individual and group variability of dry matter content, reducing sugars, total sugars, inulin content and root shape in breeding varieties of common chicory obtained by intensive breeding in Uman Experiment Breeding Station of the Institute of Bioenergy Crops and Sugar Beet – Umanskiy 90, Umanskiy 95, Umanskiy 96, Umanskiy 97, and Umanskiy  99, which are listed in the State Register of Plant Varieties of Ukraine, as well as in breeding numbers selected from variety specimens from Poland (Sleska), Hungary (Fredonia) and France (Cassel x Dagerade).

Results and Discussion. The paper presents the study results on chemical composition of breeding numbers of common chicory. The assay of dry matter content in chicory roots of individual breeding numbers showed a rather high variability, indicating a high genetic potential and possibility of breeding by this trait. Thus, the average dry matter content over the study years varied between individual numbers from 28.6 % to 31.6 % related to wet weight. Characterization of chicory breeding numbers in terms of sugar content in % related to wet weight, depending on root shape, confirmed that we used a wide gene pool of source material, which gave offspring with variability. Determination of reducing sugars in dry matter of chicory roots showed that their content varied from 0.2 to 1.3 % related to wet weight. Thus, depending on root shape, this parameter varied across breeding numbers: it was in the range of 0.8 to 1.3% for elongated roots; 0.2 - 1.2 % - for conic roots; 0.4 - 0.5 % - for cylindrical roots related to wet weight. The assay of individual variability by total sugar content in chicory roots suggests their different content. On average total sugar content in roots varied from 13.6% to 18.1% related to wet weight. During the study years the total sugar content in the major mass of roots was 15 %, 16 % and 17 % related to wet weight. Polysaccharide inulin is the main substance due to which chicory is cultivated. Accumulation of inulin in roots occurs throughout the growing season and reaches its optimum at the end of September/beginning of October, in the period of technical ripeness of varieties associated with mass drying out of lower leaves. The study of group variation in terms of inulin content in roots revealed highly significant differences between offsprings, where variations ranged from 11.5% to 15.7% related to wet weight. A lower average content of inulin during the study years was recorded in variants with elongated shape - 11.5 - 12.2 % related to wet weight, whereas a high content of inulin was noticed in breeding numbers with conic shape (14.1; 15.6; 15.7 and 16.5% related to wet weight). The test breeding numbers with cylindrical shape had intermediate values of inulin content, and the average for the study years ranged from 13.1 to 14.1% related to wet weight. Depending on root shape, fluctuations between numbers with low and high dry matter content were similar to elongated shape - 0.7 %, conic shape - 1.1 %, cylindrical shape - 1.5% related to wet weight. The presence of individual and group variability by inulin content indicates to a wide gene pool of created source material of common chicory, which is also confirmed by variability in dry matter content in roots.

Conclusions. The studies showed that in the breeding numbers the examined key traits varied: dry matter content - from 28.6 % to 31.6 %; polysaccharide inulin content - from 11.5 % to 15.7 %; total sugars - from 13.6 % to 18.1 % related to wet weight. Selection by these traits in further generations will allow maintaining individual variability, accumulating valuable properties and increasing breeding efficiency.