The increase in agrophytocenoses species and varietal diversity is of great scientific and practical importance, particularly when it comes to non-traditional or rare crops of multipurpose use. Root chicory (Cichorium intydus L. var. Sativum Lam) is one of the high-yielding crops of diverse use.

Root chicory is a valuable food, technical and medicinal plant. The largest acreage of chicory in our country is in Khmelnytsk and Zhytomyr regions. The average yield of the roots makes 20-25 t/ha. In recent years, more attention has been paid to improving the crop productivity and its natural habitat.

Chicory roots contain inulin, which promotes toxins and radionuclides excretion, 2.5 % fruit sugar, 1.2 % protein, 0.6 % fat, acrolein, furfural, valeric acid, intybin and essential oil – tsykoriol, vitamins А, B₁, В₂, В₁₂, РР and over 30 mineral elements.

In this regard, the priority task for breeders is to create high-yield varieties adapted to different soil and climatic conditions, with growing season duration of 150-170 days, diseases and pests resistant root crops which can provide the yields of 35-45 t/ha with 17-20 % inulin content in the roots.

The material was used Five root chicory varieties of Uman experimental breeding station selection IBKITSB: Umanskiy 90, Umanskiy 95; Umanskiy 96; Umanskiy 97; Umanskiy 99.

The leaves number in root chicory productive varieties of calculation by the years reveal that Umanskiy 95 variety has highest number of productive leaves in the unit per plant were obtained in 2010 – 28.0 units., which is 7.1 % more than in 2012 and 11.4 % more than in 2011. Formation of the leaves number providing assimilative surface starts with chicory germination and during the first month it is rather slow forming only 2.5 – 4.0 % of the total. The rate of increase in the second month of growth increases significantly and reaches 21.5 – 27.3 units, and the largest number is observed in the third month – 30.7 – 37.2.

At the end of the growing season the leaves die gradually and their number makes 29.3 – 25.8 units.

Umanskiy 95, Umanskiy 96, Umanskiy 97 and Umanskiy 99 chicory root varieties are notable for larger assimilating surface area on average during three years of the research, as compared to the control (Umanskiy 90) due to a slightly larger size and number of leaves.

Calculating the area of assimilating surface of chicory plants root by the research years reveals that its highest rate was received in 2010 in Umanskiy 99 variety, which was 354 cm² per plant. Umanskiy 96, Umanskiy 97 and Umanskiy 99 options varieties had medium rates and larger assimilating surface area as compared to the control (Umanskiy 90) by 8, 16 and 18 cm² per plant respectively.

During the research the value of the assimilating surface area in chicory root amounted within 32.9 – 45.1 thousand m²/ha, depending on the variety. The value of assimilating surface area in the control chicory root (Umanskiy 90) amounted to 38.0 thousand m²/ha; in Umanskiy 95 it made – 38.7 thousand m²/ha which is 1.9 % higher; in Umanskiy 96 it made – 39.6 thousand m²/ha which is 4.2 % higher; in Umanskiy 97 it made – 41.0 thousand m²/ha – which is 7.9 % higher; in Umanskiy 99 it made – 41.5 thousand m²/ha which is 9.3 % higher than in the control.

The studies results indicate that root chicory varieties are characterized by relatively high rates of net photosynthesis performance, which ranged 8,4-10,3 g/m² per day, depending on the variety.

Umanskiy 95, Umanskiy 96, Umanskiy 97 and Umanskiy 99 chicory root varieties are noted for more intense assimilating surface using, more intense synthesis of organic matter and therefore had 2.0 – 16.0 % higher productivity photosynthesis, as compared with the control (Umanskiy 90). The maximum efficiency of photosynthesis was provided in Umanskiy 99 variety – 10.3 g/m² per day.

Key words: Chicory Root, variety, productive leaves, assimilating surface of plants, photosynthesis productivity.