Field germination and preservation of safower plants (Carthamus tinctorius L.) depending on the rowspacing width and seeding rate

Taking into account extremely important signifcance of feld germination and plant preservation for their growth and development, the level of cropping capacity and product quality, it is of interest to establish the dependencies of these indicators on the elements of cultivation technology that determine the level of competitive struggle in agrophytocenoses. The conducted research was aimed at determining the inuence of various combinations of row-spacing width and seeding rate on the feld germination and the preservation of safower plants under conditions of the eastern Forest-Steppe of Ukraine with its typical frequent heat and drought during the spring-summer vegetation. The research was carried out during 2019–2020 on the felds of limited (liability) company “Kayari” Chuguievsky district of Kharkiv region. In a three-factor experiment, we studied two varieties of safower – Lahidny and Dobrynya, three variants of row-spacing width – 15, 30 and 45 cm, and fve variants of the seeding rate – 240 thousand pieces/ha, 270, 300, 330 and 360 thousand pieces/ha. Considerable dierences in the main meteorological indicators in the years of research made it possible to more fully determine the eect of row-spacing width and the seeding rate on the feld germination and plants survival of the studying safower varieties. Seeding rates in the studying range – from 240 to 360 thousand pieces/ha did not have a signifcant eect on the change in the feld germination of safower seeds of both varieties. At the same time, there was a tendency to increase this indicator due to an increase in the seeding rate. In particular, on average for the varieties and the studying variants of row-spacing width, with an increase in the seeding rate from 240 to 360 thousand pieces/ha, the feld germination of safower seeds increased by 1.1 % – from 80.2 to 81.3 %. Preservation of safower plants of both varieties signifcantly decreased with an increase in the seeding rate from 330 to 360 thousand pieces/ha. In the range of the seeding rate from 240 to 330 thousand units/ha, only a statistically unproven tendency to reduce this indicator was noted. There was no considerable dierence between the preservation indicators of safower plants on the variants with row-spacing of 15 and 30 cm. This indicates that on these variants of row-spacing width, variation of competition between plants depending on the seeding rate in the studying range does not lead to a signifcant decrease in plant preservation indicators.Key words: safower, variety, row-spacing width, seeding rate, plant preservation, feld germination.