Productivity of strawberry crops in Ukraine is 20-40 %, and the number of high-quality commercial product suitable for fresh consumption is 30-60 % of the gross output. In the conditions of potential bioclimatic changes of the Southern Region of Ukraine the problem of stability of strawberries’ agrocenosis in the unfavorable abiotic and biotic factors is very actual. One of the ways to reduce the negative impact of these factors on the growth, development and fruiting of strawberry is to use the plant growth regulators (PGR).

Reduction of operation’s term of wild strawberry’s plantations in open ground up to 1-2 years and enhancement of these areas in the protected ground, that can led to increasing needs in plant material, the quality of which in spiteof planting dates allows to return faster to the newly established plantations. Regulators of plant growth also help in solving this problem. It was evidenced by the results of research on the cultivation of strawberry seedlings in the Krasnodar region of Russia. But in the southern Steppe of Ukraine such research is practically absent, and the problem of the use of plants growth regulators in cultivation of strawberry seedlings with closed root system is poorly highlighted.

 The purpose of our research was to establish the impact of natural growth regulator Ultragumat on the growth and development of seedlings in strawberry garden. Researches were made in 2011-2013 on the experimental field and in the laboratory of plant physiology and biochemistry in the Tavria state agrotechnological University agricultural technologies and ecology Research Institute. The uterine plantations of wild strawberry Honey varieties were used for our experiments. Outlet were separated from the mother plant in the phase of formation of the embryonic roots and were planted in cassettes with the size of cells 3,5x3,5 cm and volume of 50 cm3. Uterine plants were cultivated by solution of Ultragumat (0,05%), and sockets after landing in a cassette were watered twice with a solution of Ultragumat in the same concentration. Water was used in the control. Seedlings were grown in shady polyethylene greenhouses, equipped with mist proceeding, where the relative humidity below 80 % was supported during 21 days. The dew was supported on the leaves during the first 10 days by using sprinklers every hour on 2-3 min.

Plants which were grown using Ultragumat had a 13,8 – 36,7 % more number of roots and 7,8 - 16,5 % longer root system, as compared with the control. It is found that due to complex cultivation of uterine plants and irrigation in the rooting of cuttings, accommodation rudiments of roots and roots in the zone of the rhizogenesis was more steady. Due to action of Ultragumat 11,6 - 22,9 % more leaves on the plant were formed, and the area of leaf surface increased by 10,1 - 50,1 %, compared to the another situation where growth regulator is not used. Impact Ultragumat on the formation of a sheet surface depends on the way of its use and the period of sockets rooting. The greatest effect provides spraying uterine plants and two-time irrigation during rooting them in cassettes. The accumulation of dry substance in the roots of seedlings grown with using of Ultragumat causes the high frost resistance of plants, especially for the southern Steppe zone of Ukraine, which has a snowy winters with extreme variations in temperature.

It is found that the spraying of uterine plants and irrigation sockets during rooting with solution Ultragumat stimulates the biosynthesis of plastid pigments, increases photosynthesis productivity by increasing the pigment Fund and leaf area, functional activity of chlorophyll-a.

In this way, the use of plant growth regulator Ultragumat in growing strawberry seedlings by cassette method provides intensification of the growth and development of plants, stimulates root system formation. Ultragumat of natural origin by the character of the action on the plants can be considered to be anti-stress drugs.

Key words: strawberry, seedling, the regulator of growth, productiveness, pigments.