Responses of sunflower (Helianthus annuus L.) to irrigation and nitrogen fertilization rates

Abstract

This study was conducted to determine the effects of different nitrogen rates (0, 40, 80, 120, 160, 200 and 240 kg ha -1 N) on the yield, its components and the quality characters of sunflower (Helianthus annuus L.) and to identify the economic optimum N rate for maximum profit under both irrigated and non-irrigated conditions during a 2-year period (2007)(2008). As the N rates increased, all of the traits measured significantly increased, except the crude oil content, under both irrigation treatments. Based on the 2-year average, the highest seed yield (2713.6 to 2751.2 kg ha -1 ) and crude oil yield (1012.7 to 1042.5 kg ha -1 ) were obtained using 160 kg ha -1 N and the higher N rates, with increases of 47.8% and 39.4%, respectively, compared to the control (0 kg ha -1 N). Similar trends were also obtained for the other traits, except the crude oil content, which was the highest (39-41%) at 0 kg ha -1 N but the lowest (36-38%) under the higher N rates N more than that for non-irrigated conditions, the seed yield under the irrigation conditions was approximately 65-79% higher compared with the non-irrigated conditions. As a result, it was determined that the economic optimum N rate for sunflower was 145-150 kg ha -1 N under non-irrigated conditions and 177-190 kg ha -1 N under irrigated conditions.

Influence of Application Methods of Biochar and Poultry Manure on Yield and Nutrients Uptake of Sunflower Plant Fertilized with Different Nitrogen Rates.

“…These results may regard to nitrogen role in activating the growth and yield components. These results are in line with that of Awed 2010 andSincik, et al (2013). They studied the effects of different nitrogen rates (0,40,80,120,160,200 and 240 kg ha -1 N) on the yield, its components and the quality characters of sunflower.…”

“…Agbede 2009,). On the other hand, many researchers stated that nitrogen fertilizers significantly increased sunflower plant height, dry matter, seed production, oil yield (Oyinlola et al, 2010;Sincik et al, 2013;Salih, 2013). However, other investigator found that seed oil percentage decreased with increasing nitrogen fertilizer rates (El-kady et al,2010 andAwed 2010).…”

Response of Sunflower to Nitrogen Fertilization and Plant Density in Sandy Soils

“…Several researchers revealed that oil yield/fad was increased by increasing nitrogen fertilization, Basha (2000), Mohamed (2003), Al-Thabet (2006), Hassan (2010), Yasein (2010) and Sincik et al, (2013).…”

“…The favorable effects of applying mineral nitrogen fertilization on growth, yield attributes, seed yield and quality of sunflower were reported by Zeiton (1992), Geweifel et al, (1997), Metwally (1997), El-Kalla et al, (1998), Abou-Khadrah et al, (2000), Basha (2000), Abd El-samie et al, (2002), Abou-Khadrah et al, (2002), Ibrahim et al, (2003), Khalil (2003), Mohamed (2003), Ali et al, (2004), Al-Thabet (2006), Ibrahim et al, (2006), El-Sarag (2007), Gholinezhad et al, (2009), Hassan (2010), Sala et al, (2010), Soleimanzadeh et al, (2010), Yasein (2010), Ali et al, (2012), Namvar et al, (2012), Wabekwa et al, (2012), Ali and Noorka (2013) and Sincik et al, (2013).…”

Measurements of chlorophyll fluorescence in different leaf positions may detect nitrogen deficiency in wheat

“…Nitrogen fertilization is one of the most important crop management techniques for production of field crops (Janušauskaitė, 2013), especially in conditions affected by adverse environmental factors (Sincik et al, 2013). Nitrogen nutrition influences the plant photosynthetic capacity through the decrease of synthesis of several key photosynthetic enzymes, especially of Rubisco (ribulose-1,5-bisphosphate carboxylase/oxygenase), thus affecting the carbon assimilation, and subsequently also the photochemical processes in thylakoid membranes (Harbinson et al, 1990).…”