Abstract:

The study aims to explore the effect of main cultivation factors on the yield of oil sunflower, and determine the optimal cultivation scheme of oil sunflower in northern Hebei Province. Five-factor quadratic orthogonal regressive rotation design was applied to establish an effect function of sowing date, density, nitrogen fertilizer, phosphate fertilizer, potash fertilizer and the yield of oil sunflower. The results showed that the yield of oil sunflower increased first and then decreased with the change of sowing date, the increase of planting density and the increasing application rate of nitrogen fertilizer, phosphate fertilizer and potash fertilizer, wherein sowing date and the interaction between sowing date and nitrogen fertilizer played an important role. When the target yield was more than 2916.67 kg/hm², the optimal cultivation scheme was as follows: the sowing date of June 30^th -July 5^th, the sowing density of 54749-55478 plants/hm², the application amount of nitrogen fertilizer of 80.0-85.7 kg/hm², phosphate fertilizer of 44.4-45.0 kg/hm² and potash fertilizer of 70.3-75.0 kg/hm².

Key words: oil sunflower, orthogonal design, nitrogen, phosphorus and potassium, north Hebei, model optimization