Effects of different intra- row spacings on yield and quality of newly developed sunflower hybrids

This study aimed to determine the effects of different row spacings on yield and quality in hybrid sunflower (Helianthus annuus L.) varieties developed by Selçuk University Faculty of Agriculture and Pankobirlik, within the scope of University-Industry Cooperation Projects, and for which production permits were obtained on behalf of Pankobirlik. The experiment was conducted in randomized block split-plot design with four replications in Konya-Ilgın conditions. The permitted varieties PB ADA N, PB 105 N, and PB 250 N, the newly developed hybrid candidate for registration H1024, and the commercial variety GİBRALTAR were used as trial materials. Fixed row spacings of 70 cm and 15, 20, and 25 cm were used in the experiment. In the study, varieties will constitute the main plots, and row spacings will constitute the sub-plots. In the experiment, plant height (cm), stem diameter (cm), head diameter (cm), thousand grain weight (g), seed yield (kg/da), oil ratio (%) and oil yield (kg/da) will be examined. The varieties used in the research had plant heights ranging from 123.6 cm (PB ADA N) to 140.6 cm (PB 250 N), trunk diameters ranging from 7.7 cm (PB ADA N) to 8.4 cm (PB 250 N), head diameters ranging from 18.1 cm (PB ADA N) to 20.8 cm (PB 105 N), thousand grain weight ranging from 83.3 g (PB 205 N-H 1024) to 102.5 (Gibraltar), seed yield ranging from 424 kg/da (Gibraltar) to 454 kg/da (PB ADA N), oil content ranging from 37.9% (Gibraltar) to 46.7% (PB2025 N), oil yield ranging from 106.7 kg/da (Gibraltar) to 193.9 kg/da (PB ADA N). The results of the study revealed statistically significant differences in grain yield among varieties and row spacing. The highest grain yield, 443 kg/da, was achieved at a 25 cm row spacing, based on the average of the varieties. The highest yield, 454 kg, was achieved by the PB ADA N variety. Consequently, PB ADA N was the most suitable sunflower variety for Konya Ilgın conditions, with a plant density of 70 cm between rows and 25 cm between rows.