FORMATION OF PRODUCTIVITY OF WINTER RAPE HYBRIDS DEPENDING ON ROW SPACING
Authors: Zabarnyi O. S. , Zabarna T. A. 
Published: October 2023

Recently, the popularity of winter rape cultivation in Ukraine has been growing rapidly. Rapeseed can easily enter the world's largest markets, so its cultivation is of great economic importance. Increased productivity of rapeseed and improved seed quality are the most important criteria of modern cultivation technology. The main criteria of the technology components that have a certain impact on the yield level is the row spacing, which must be taken into account when cultivating it in different soil and climatic conditions. Scientists have proven that non-compliance with the technology of winter rape cultivation affects the yield of this crop. The problem of technological definition and methodological support for optimising the elements of this crop's cultivation technologies in order to increase yields and seed quality remains quite relevant. It is the winter type of rapeseed that ensures efficient use of precipitation, the amount of which varies considerably in all regions of Ukraine, which further contributes to a full harvest. In addition, winter rapeseed is characterised by high multiplication rates, which results in a low seeding rate of 3-6 kg/ha. The purpose of the research was to study the peculiarities of winter rape yield formation and to establish the dependence of the height and weight of a thousand seeds depending on the sowing width, as well as to investigate how the oil content changes depending on the experimental variants in the forest-steppe of right-bank Ukraine. The following methods were used in the course of the study: field, measuring and weighing, biochemical and balance-calculation. The research was conducted with two winter oilseed rape hybrids from BASF: INV1030 - a medium-ripening hybrid, and INV1165 - a medium-late hybrid. The winter oilseed rape hybrids were sown with the following row spacing: 15 cm for conventional rows, and 40 and 70 cm for wide rows. The sowing rate of winter rape hybrids was 500 thousand units/ha at 15 cm row spacing, 340 thousand units/ha at 40 cm row spacing and 270 thousand units/ha at 70 cm row spacing. With a row spacing of 15 cm, the distance between winter rape plants in a row was 13.3 cm, and the feeding area per plant was within 2 cm2. Increasing the row spacing to 40 cm made it possible to expand the feeding area for one rape plant to 2.9 cm2, but the distance in the row decreased to 7.3 cm. Sowing winter rape hybrids with a row spacing of 70 cm provided an average feeding area per plant of 3.7 cm2. At the same time, the distance in the row between plants, under these growing conditions, decreased to 5.3 cm, which in turn contributed to the growth of intraspecific competition. Studies have shown that row spacing significantly affected the height of plants of both winter rape hybrids. Thus, with a row spacing of 15 cm, the plant height of the INV1030 hybrid was 157 cm, and that of the INV1165 hybrid was 161 cm. At a row spacing of 40 cm, the height of winter rape plants of INV1030 in the pre-harvest period decreased to 151 cm, and in the hybrid INV1165 - to 153 cm. The smallest plants of winter rape in the pre-harvest period were on the variants of cultivation with a row spacing of 70 cm. The height of the INV1130 hybrid was 145 cm, while the height of the INV1065 hybrid was 148 cm. With a narrow-row sowing method (15 cm), the oil content in the seeds of the INV1030 hybrid was 48.8%, while in the INV1165 hybrid it was 46.5%. Increasing the feeding area for plants and the ability to branch well with increasing row spacing had a positive effect on the accumulation of oil in the seeds. Sowing of winter rape hybrids with a row spacing of 40 cm contributed to the fact that the oil content in the seeds of winter rape INV1030 was 49.5%, and in the hybrid INV1165 - 47.2%. The highest oil content in rapeseed was when it was grown with a row spacing of 70 cm, and was 50.3% in hybrid INV1030 and 48.0% in hybrid INV1165. It was found that the weight of 1000 seeds of winter rape hybrids in the experiment was 3.8-3.9 g with a narrow-row sowing method (15 cm). With an increase in row spacing to 40 cm, the weight of 1000 seeds in hybrids increased to 4.2-4.4 g. The weight of 1000 seeds in winter rape hybrids reached its highest value when sown with a row spacing of 70 cm, with INV1030 hybrid having 4.7 g and INV1165 hybrid having 4.8 g. With a narrow-row sowing method with a row spacing of 15 cm, the seed yield of the INV1030 hybrid was 43.3 t/ha. Under similar growing conditions, the winter rape hybrid INV1165 formed 0.9 t/ha more seeds, while the yield was 44.2 t/ha. With an increase in row spacing to 40 cm, a slight decrease in the yield of winter rape hybrids was observed at the level of 0.3-0.5 t/ha. Under these growing conditions, the hybrid INV1030 produced 43.0 t/ha of seeds, and the hybrid INV1165 - 43.7 t/ha. Further increase in row spacing to 70 cm, when sowing winter rape, led to a decrease in the yield of both hybrids. Thus, the yield of the hybrid INV1030 was 41.6 t/ha, which is 1.7 t/ha less than with the narrow-row sowing method. The yield of hybrid INV1165, with this sowing method, was 42.4 t/ha. At the same time, the decrease in the yield of rapeseed compared to the narrow-row method (15 cm) was 1.8 t/ha. Further increase in row spacing to 70 cm, when sowing winter rape, led to a drop in the yield of both hybrids. Thus, the yield of the hybrid INV1030 was 41.6 t/ha, which is 1.7 t/ha less than with the narrow-row sowing method. The yield of hybrid INV1165, with this sowing method, was 42.4 t/ha. At the same time, the decrease in the yield of rape seeds compared to the narrow-row method (15 cm) was 1.8 t/ha.