Research results of suitability of lettuce cephalate of Polish selection to cultivation under the conditions of the Right-Bank Forest-Steppe of Ukraine are presented. The peculiarities of the oncoming and passing of phenological phases of plants development depending on the varietal characteristics of plants under the conditions of the study area are stated. Biometric parameters of plants during planting out in open soil at early phase of forming of the rosettes of leaves and during harvesting are defined. Indicators of yield level during years of research are analyzed and the level of profitability of cultivation of lettuce cephalate in open soil is determined.

The aim of the research was to expand assortment of high-yielding varieties of lettuce cephalate of Polish selection and thus to rise productivity of green culture under the conditions of the Right-Bank Forest-Steppe of Ukraine. In accordance with the intended purpose, the task of the research included defining more productive and effective varieties among the varieties of Polish selection concerning the soil and climatic conditions of the Right-Bank Forest-Steppe of Ukraine that meet the needs of producers and consumers better.

The research was conducted by conventional methods during 2012-2014 with varieties of lettuce cephalate of Polish selection, Edita ozharovska, Etti, Fortunas.  Domestic variety Godar was taken under control.

Phenological observations of plants were conducted during the growing season. Appearance of individual and mass springs was marked in the planting period, the first real leaf and rosette of 4-5 leaves was formed.

After planting out in open soil setting of a head, technical ripening and harvesting was fixed.

Biometric measurements were carried out in due time during the growing season. Lettuce heads were weighed and their diameter was measured during harvesting. Harvest was sorted in accordance with the state standard DSTU 2175–93 “Green vegetables” and DSTU ISO 8683-2001 "Lettuce. Guidelines for Storage and Transportation in Refrigerated Condition".

The study of the varieties of lettuce cephalate Godar, Edita ozharovska, Etti and Fortunas found that under conditions of the Right-Bank Forest-Steppe of Ukraine during the growing season plants were characterized by uneven growth and development, certain difference in the oncoming and passing of some phenophases was observed depending on the variety and climate conditions of the year.

However, on average for the period of 2012-2014 there was no significant difference in passing phenological phases – they started with the difference of 1-3 days and they started later for Godar (control).

Assessment of seedlings quality in terms of phytometric indicators shows that at the time of planting out in open soil the number of leaves of foreign varieties Etti and Fortunas was higher in relation to control and amounted to 5.6 pc respectively. Foreign varieties had bigger diameter of the rosette of plants as well as the number of leaves at the time of planting out. Thus, rosette of leaves of Godar variety (control) grew up to the diameter of 13.4 cm while other varieties’ indicator ranged 14.6-17.5 cm.

Average data in the course of the years of studies has shown that Godar variety plants formed leaves with smaller area – 22.4 cm², and therefore the surface of leaves was smaller – 29.2 cm². Fortunas variety had larger area of leaves and larger total surface of leaves – 29.2 cm² and 175.2 cm² respectively.

Therefore, at the period of planting out in open soil seedlings of lettuce cephalate of foreign variety had better plant biometrics compared with plants of native brand Godar. After planting out seedlings in open soil, plant biometrics hardly changed in the period of adaptation.

At early technical ripening foliation of lettuce was 9-14 pcs/plant. Godar variety had lower indicators while Edita ozharovska had more leaves. Analyzing the size of the diameter of the plant, it should be noted that this indicator prevailed over native variety Godar than of the varieties of foreign selection.

The undertaken studies show that varieties of lettuce cephalate create a rather large vegetative mass in a short growing season, compared to other vegetable plants. Higher levels of productivity were obtained while growing Fortunas variety – 16.7 t/ha, which prevails control at 30 % and ensures profitability of 81 %. Rather lower crop yield was received from Etti and Edita ozharovska varieties that is 14.9 t/ha and 14.0 t/ha respectively, which prevails control at 16% and 9%. Lower crop yields indicator was shown by Godar variety – 12.9 t/ha which provided profitability of 43 %.

Consequently, the undertaken studies indicate suitability of lettuce cephalate of Polish selection to growing conditions in the Right-Bank Forest-Steppe of Ukraine on podzolized black soil and calculation of economic efficiency proves the expediency of their use under the conditions of open soil of the study area.

Key words: lettuce cephalate, variety, Godar, Edita ozharovska, Etti, Fortunas, productivity, crop yield.