The effect of harvest index, yield and yield components of three varieties of black seed (Nigella sativa) in different planting densities

This study was conducted in the form of a factorial experiment in completely random blocks with 4 replications. In this research the first factor (A) was the inter row level, at intervals of 20 and 40 cm; the second factor (B) was the intra row level, at three levels of 2, 4 and 6 cm; and the third factor (C) was the three varieties of Nigella sativa Baft, Bukan, and Arbil. The specimens were planted on April 22nd, 2009. Results showed that the effects of plant density and cultivation arrangement on weight of capsule, total weight of stem, leaf weight, seed weight, 1000-grain weight, seed efficiency and harvest index were significant. Baft cultivar had the best results for seed efficiency, but the Arbil variety had the best results for 1000-grain weight. Seed efficiencies at the inter row spacing of 20 cm, of intra row spacing of 2 cm, and Baft variety were 1920.3, 2336.9, and 2148.1 kg/ha respectively. Harvest Indexes of the intra row spacing of 6 cm, and for the Baft variety were 25.65%, and 25.84% respectively. The Baft variety planted at 20 cm inter row and 2 cm intra row spacing was overall, the most efficient planting arrangement for Nigella Sativa.