Yield and yield components of two rapeseed cultivars as affected by plant population and seeding date

摘要

A field experiment was carried at Darab Agricultural Experimental Center to determine the effects of plant population and seeding date on yield and yield components oftwo rapeseed (Brassica napus L.) cultivars (CVS), Hyola 308 and Hyloa 401. The experiment was conducted as factorial design arranged in randomized complete block with four replications. Plant population were 48, 67 and 111 plants per m2 and seeding dates were Oct. 22, Nov. 11 and Dec. 1, 2002. Increased plant population significantly increased harvest index (HI) and seed protein percentage and decreased pods per plant. Delayed seeding significantly decreased pods per plant, pods per m2, 1000-seed weight, harvest index, seed oil percentage and significantly increased seeds per pod and seed protein percentage. Seeding date did not significantly increase seed yield, however, the highest seed and oil yields were obtained at the 2nd date. There was significant difference between two cultivars for pods per m2, seeds per pod, 1000-seed weight, HI and seed protein percentage. Hyola 308 cultivar had more pods per m2, seeds per pod, HI, 1000-seed weight and oil yield. Interaction between seeding date, plant population and cultivars on seed yield were significant and the highest seed yield (5537 kg/ha) was obtained from early seeding of Hyola 401 at 48 plants perm2. Delayed seeding and increased plant population decreased seed and oil yields in both cultivars.