Effects of Sowing Techniques and Seed Rates on Oilseed Rape Seedling Emergence, Crop Establishment and Grain Yield

Abstract

Sowing techniques and type of seeding machines, play an important role in seed placement, and seedling emergence which ultimately affect crop growth and grain yield. The selection of suitable planting methods is dependant upon the time of planting rapeseeds, irrigation methods, amount of residue in the field and type of planting machines. A field experiment was conducted at Zanjan University research station in 2006. The main goals were to determine the effects of different seeding techniques and machines, and also different rates of oilseed rape application on seedling emergence, plant establishment and final grain yield. A factorial experimental design in the form of randomized complete block was applied with four replications to measure the effects of the above factors. Two different pneumatic and common mechanical planter were used. Seeds were sown on flat and raised-bed with three levels of 5.5, 7, 8.5 kg seeds per hectare. Results showed that the planting machines had significant (P?0.05) effect on seedling emergence. Mechanical planter had higher seedling emergence than pneumatic planter. Mechanical planter sowing the amount of 8.5 kg/ha seed showed higher seedling emergence (P?0.05) than others. Uniformity on row and proper seed depth of mechanical planter was significantly greater (P?0.01) than pneumatic planter. Flat planting method showed more uniformity on rows (P?0.05) than raised-bed. Pneumatic planter improved better post-winter plant establishment in comparison with mechanical planter (P?0.05). Finally, grain harvested using pneumatic planter with flat planting method was greater when 8.5 kg/ha seed was applied at sowing in the experiment conditions. However, grain yield was not statistically different.