Effect of Plant Density on Yield and Yield Seed Components of Rapeseed (Brassica napus) Cultivars

To study the effects of different plant density on seed yield and yield components of three spring rapeseed cultivars a factorial experiment based on a Randomized Complete Block Design with three replications and 9 treatments was carried out during 2011 in Qazvin, Iran. Each plot consisted of 4 rows, 6 m long with 60 cm between rows. Seed were sown by hand (without pre planting irrigation) on February 2. Application of fertilizers, herbicides, pesticides and irrigation regime in this experiment were processed as they are usually done in the region. Three rapeseed cultivars Hayola401، RGS003 and Sarigol with three plant density levels (60, 80 and 100 plant/m2) were studied. At the end of growing period, traits like silique number per plant, seed number per silique and 1000 seed weight, seed yield and seed oil percent were measured. The results showed that plant density and cultivars affected silique number per plant, seed number per silique, 1000 seed weight and seed yield significantly. The effects of plant density by interaction on silique number per plant, seed number per silique and seed yield were also significant. Hayola401 produced the highest silique number per plant, seed number per silique, 1000 seed weight and seed yield. In these three cultivars under study the highest seed yield was obtained with the plant density of 80 plant/m2. Increasing plant density from 80 to 100 plants/m2 decreased silique number per plant, seed number per silique, 1000 seed weight and seed yield. This study showed that Hayola401 produced highest seed yield (1918/5 kg/ha) at plant density of 80 plant/m2.