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

Summary The responses ofyield and quality traits ofsunflower (Helianthusannuus1.) to row orientation, row spacing, and plant density were studied in a rhree year field experiment (1996, 1997, 1998) conducted at a high-latitude site (51 °24' N) in central Germany. There were two row orientations (east-west; north-south), three row spacings (50, 75, and 100 cm), and three plant densities (four, eight, and 12 plants m- 2 ) . Sunflower planrs in east-west rows yielded on average 12% more oil than plants in north-south rows. The higher yield of planes in the east-west rows was mainly the resulr of a greater number ofachenes m- 2 ; both aboveground biomass and the harvest index tended to be higher in the east­ west rows than in the north-sourh rows. The maximumyield was produced in the east-west rows at four to eight plants m- 2 and 75 to 100 cm row spacing.