Growth, Achene Yield and Oil Content of Sunflower (Helianthus annuus L.) as Affected by Row Spacing

Exploring the effects of row spacing is of crucial significance to achieve the economically optimum achene yield and oil content of sunflower. We conducted a field study during Kharif 2023 to study the effect of row spacing on growth and yield of sunflower. The experiment was administered in a randomized complete block design with three replications. Sunflower was grown providing five different row spacings, viz. 25, 30 (recommended), 35 cm, 40, and 45-cm. The crop was raised following standard recommended agronomic practices and balanced fertilization. Our findings suggested that narrow row spacing (25 cm) significantly enhanced the vegetative traits of sunflowers, i.e., plant population and plant height. In contrast, wide row spacing found significantly beneficial in decreasing the days to 50% flowering (at 40-cm) and days to 50% maturity (at 45-cm). Interestingly, wider row spacing (45-cm followed by 35-cm) significantly enhanced stem girth, head diameter, achene per head, achene weight per head, 1000-achene weight, achene yield, and oil content of sunflower. It was evident that the improved yield traits of sunflower, especially achene characteristics, enhanced the achene yield and oil content of sunflower. In contrast, all these traits were found to be lowest where sunflower was planted in rows that were 25-cm apart. We conclude that sowing of sunflower with a wide row spacing of 45-cm, as against comparatively narrow row spacings, significantly improves its yield contributing traits, achene yield, and oil content.