Yield and quality of sunflower as affected by row orientation, row spacingand plant density

The responses of yield and quality traits of sunflower (Helianthus annuus L .) to row orientation, row spacing, and plant density were studied in a thr ee year field experiment (1996, 1997, 1998) conducted at a high-latitude si te (51 degrees 24 ' N) in central Germany. There were two row orientations (east-west; north-south), three row spacings (50, 75, and 100 cm), and thre e plane densities (four, eight, and 12 plants m(-2)). Sunflower plants in e ast-west rows yielded on average 12% more oil than plants in north-south ro ws. The higher yield of plants in the east-west rows was mainly the result of a greater number of achenes m(-2); both aboveground biomass and the harv est index tended to be higher in the east-west rows than in the north-south rows. The maximum yield was produced in the east-west rows at four tu eigh t plants m(-2) and 75 to 100 cm row spacing.