Field germination and preservation of grain sorghum plants depending on the row-spacing width and the seeding rate
Authors: Rozhkov A.A. , Davydenko S.Yu. 
Published: March 2021

The results of two-year research on the complex effect of different options of row-spacing width and the seeding rate on field germination and preservation of grain sorghum hybrids plants are presented.
Problem statement. The conservatism of agricultural products producers, as well as the lack of adaptive technologies for growing sorghum, is a limiting factor of enlargement of sorghum sowing areas. That is why improving the technology of sorghum growing, which forms high and stable yields under arid conditions, is a relevant task at the current stage of country's agricultural sector development.
The aim of the research was to determine the influence of various options of combining the seeding rate and row-spacing width on field germination and preservation of grain sorghum plants under conditions of the Northern Steppe of Ukraine.
Research methods. Research on study the influence of three row-spacing width – 35, 45 and 70 cm and four options of the seeding rates of 100, 140, 180 and 220 thousand pieces/ha on field germination and preservation of sorghum plants of Svat and Flagg hybrids were held in 2019, 2020 on the basis of Farming Enterprise "Dyunis" of Kreminsk District, Luhansk Region. The area of sown and accounting plots was 40.0 and 30.0 m2, respectively.
Research results. In experiments we have noted the tendency to increase field germination, under condition of the seeding rate increases and row-spacing widening. The influence of the studying options of the seeding rate and row-spacing on plant preservation was significantly higher than on field germination. On the crops of both hybrids, the influence of the seeding rate to a greater extent manifested on the options with row-spacing of 70 cm. Thus, with an increase in the seeding rate from 100 to 220 thousand pieces/ha, the plant preservation on the options with 35 cm row-spacing decreased by 3.5 %, while on the options with 70 cm row-spacing – by 6.7 %. There was no significant difference between the plant preservation indicators obtained on the options with row-spacing of 35 and 45 cm. With the widening of the row-spacing to 70 cm, this indicator significantly decreased.
Conclusions. The studied element of the cultivation technology provided certain changes in the indices of field germination of seeds and the safety of sorghum plants. More influence they have on the safety of the plant, since the start of the growing competition between the plants is much less. An increase in the seeding rate caused a significant decrease in plant preservation, and to a greater extent with an increase in the seeding rate from 180 to 220 thousand pieces/ha. In the seeding rate from 100 to 180 thousand pieces/ha, there was no significant variation in the survival rates of sorghum plants. There was virtually no difference between the survival rates of sorghum plants in variants with row spacing of 35 and 45 cm, which indicates that within the boundaries of these row spacing, the competition between plants does not change significantly.
Key words: row-spacing width, seeding rate, sorghum, hybrid, field germination, plants preservation.