Abstract:

To study the effects of nitrogen, phosphorus and potassium fertilizers on the yield and yield related traits of confectionary sunflower, and to find the balance between the optimal fertilizer application rate and economic benefits, the 3414 design was used for 3 years to establish the effect functions of nitrogen, phosphorus and potassium fertilizers on the yield and related traits. The results showed that the effect order of the three fertilizers on sunflower yield was potassium > nitrogen > phosphorus. The effect order on 100-seed weight and single disk seed weight was potassium > phosphorus > nitrogen. All the single-factor effects of nitrogen, phosphorus and potassium fertilizers on yield, 100-seed weight and single disk seed weight showed a trend of first increase and then decrease. Among the interaction effects of two factors, phosphorus-potassium interaction produced the highest yield. Fertilizer combination for the highest yield was nitrogen 61.5 kg/hm², phosphorus 35.0 kg/hm² and potassium 50.1 kg/hm², the yield was 2309.0 kg/hm², and the ratio of production to investment was 13.8. The fertilizer combination for the most economic yield was nitrogen 57.5 kg/hm², phosphorus 34.9 kg/hm², potassium 47.9 kg/hm², the yield was 2307.8 kg/hm², and the ratio of production to investment was 14.3. The most economic yield is with less fertilizer, low fertilizer cost, low output value, high income, and high production to investment ratio.

Key words: confectionary sunflower, nitrogen, phosphorus and potassium fertilizers, 3414 design, yield related traits, interaction effect, economic benefits