Protein, Oil, and Energy Yields of Sunflower as Affected by N and P Fertilization¹

Abstract

Relatively little information exists on the N and P needs of sunflower (Helianthus annuus L.) on infertile soils in non‐traditional production areas. The effects of four levels each of N (0 to 180 kg/ha) and P (0 to 60 kg/ha) applied to a thermic Typic Rhodustult were evaluated over three seasons. In all seasons there were highly significant seed yield responses to N and P a plied. The nature of the N ✕ P interactions indicated a greater response to N fertilization where P had been applied than in the absence of P fertilization. Maximum seed yields of up to 2,600 kg/ha were four to 13 fold higher than yields in the absence of applied N and P. Protein level in the seed was increased by N but decreased by P fertilization, the opposite effects being generally observed with respect to the oil. Nitrogen and P fertilization markedly increased the protein and oil yields, the N ✕ P interactions indicating that P fertilization was necessary for maximum response to applied N. The ratio of seed N to fertilizer N decreased with increased N fertilization but increased with increased P applied. The food energy yield and energy production efficiency of sunflower increased markedly with both N and P fertilization.

Response of irrigated sunflower (Helianthus annuus L.) hybrids to nitrogen fertilization: growth, yield and yield components

“…It is noteworthy that compared to the control the highest N rate produces in a 9% increase in protein concentration. Previous research has indicated that nitrogen fertilization tends to increase seed protein content at the expense of oil (Blamey andChapman 1981, Steer et al 1986). …”

“…Numerous studies have investigated the effects of N fertilization on sunflower in the various parts of the world (Hussein et al 1980, Blamey and Chapman 1981, Kandil 1984, Narwal and Malik 1985, Khokani et al 1993, Legha and Giri 1999, Tomar et al 1999, Zubillaga et al 2002. Nitrogen is commonly a limiting factor in sunflower production (Zubriski andZimmerman 1974, Robinson 1978).…”

Response of Two Sunflower (Helianthus annuus L.) Cultivars To Different Levels of Nitrogen

“…Kamel et al (1980) reported that nitrogen application did not affect the oil content of sunflower seed either way. On the other hand, Blamey and Chapman (1981) and Kasem and El-Mesilby (1992) observed that increased doses of N application decreased the oil contents of sunflower seed. Similar results were also reported by Nazir et al (1986), but Steer et al (1986) and Manoharan et al (1991) reported that oil contents of sunflower seed were increased by N fertilizer.…”

Effects of Sewage-Sludge Application on Soils and Sunflower Yield: Quality and Toxic Element Accumulation

“…One reason for this behavior is the high-energy requirements of the oil, the final sink of photoassimilates (Andrade, 1995). Another problem related to this crop is that its large nitrogen (N) uptake reduces oil production (Blamey and Chapman, 1981). Knowledge about the effects of nutrient supply on sunflower and fertilization technology has increased significantly in the last few years (Loubser and Human, 1993;Zubillaga et al, 2002).…”