Effects of twin-row planting pattern in different population densities on yield and yield components of hybrid sunflower (Helianthus annuus L.) cultivars

This research was performed to determine different twin row application on yield and yield components of hybrid sunflower cultivars. Experiments were conducted at farmer field in Cevizköy village, Pınarhisar, Kırklareli during 2017 and 2018 sunflower growth seasons according to the split plot design in a randomized complete block design with four replications. Pioneer P64LE119, Limagrain LG5542 CL and May METEOR CL hybrid sunflower cultivars widely grown in this production area were used as research materials. Six different twin rows (80x30 cm, 80x40 cm, 80x50 cm, 90x30 cm, 90x40 cm and 100x30 cm) and control row spacing (70x70 cm) were applied to determine their effects on sunflower yield and yield components. At all applications, distance between plants in a row was kept as 22 cm. In this research, days number from planting to the first flowering, days number from planting to 50 % flowering, days number from planting to end of flowering, plant height, stem diameter, head diameter, thousand seed weight, seed yield per decare, oil content and oil yield per decare were determined as yield and yield components. As the variance analyses results, different twin row applications had significantly effects on all yield and yield components. The highest thousand seed weight was determined in 80x40 cm and 80x50 cm applications. Seed yield per decare was significantly affected by application, cultivar, year and all interactions among factors. Seed yield per decare ranged from 195,01 to 309,10 kg according to cultivar, year and application. Limagrain LG5542 CL hybrid sunflower cultivar gave the highest seed yield. According to means of application, the highest oil yield, seed yield and seed weight were determined in 80x50 cm and 80x40 cm twin row applications. In addition, 90x30 cm twin row application had also been in highest seed yield groups with above applications. The highest oil content was measured in 100x30 cm application including the largest one row spacing. The effects of applications on seed yield were changed according to cultivar and climatic factors depend on years. Keywords: Cultivar, oil content, row distance, seed yield, sunflower,