Effect of genotype, seeding rate and sowing date on grain yield and seed shattering in spring rapeseed (Brassica napus L.)

This research was carried out for studying on adaptation and effect of genotypes، seeding rate and sowing date on yield in spring rapeseed in Kermanshah city. The design was in split-factorial experiment in completely randomized blocks. The main plots were sowing date in 3 levels (4 Feb.، 20 Feb. and 5 Mar.) and minor plots were as factorial experiment that including the different combination of 7 spring rapeseed genotypes (Hyola60، Hyola401، Sarigol، Hyola420، RGS003، Hyola308 and Hyola330) and seeding rates (10، 14 and 18 Kg/ha). Harvesting was done in desirable time and yield was recorded. Statistical analysis showed that the effects of genotype and sowing date were significant and seeding rate and interaction effects were non-significant on yield. For seed shattering، the effect of seeding rates was significant and genotype، planting time and interaction effects were non-significant on it. Means comparison test showed that RGS003 and Hyola420 were the best genotypes (1740 and 1695 Kg/ha respectively) and 20 Feb. and 5 Mar. were the best sowing date (1420 and 1433 Kg/ha respectively) for seed yield. The Sarigol genotype and 4 Feb. sowing date had the least yield among treatments (714 and 735 Kg/ha respectively). The Hyola420 cv. in 5 Mar. sowing time and 10 kg/ha seeding rate was the best (with 1795 Kg/ha) and the Sarigol cv. in 4 Feb. sowing time and 10 kg/ha seeding rate was the least (with 95 Kg/ha) interaction effects.