Lamyaa , A. Abd El-Rahman, Dalia A. Sayed and Magda, A. Ewais ( 2016). Seed yield and quality of sunflower (helianthus annuus l. ) as influenced by integrated mineral and organic, nitrogen fertilization systems .Journal of Soil Sciences and Agricultural Engineering – Volume 7 No. (1), January,2016
Abstract: Two field experiments were conducted during the two successive seasons of 2013 and 2014 at El- Gemmeiza Research Station (30º 47׳ 22.5״ N, 31° 07׳ 34״ E, elev. 10 m), Agriculture Research Center, El-Gharbia Governorate, Egypt to study the effect of integrated fertilization of N- mineral and organic fertilizer combined with bio fertilizer (including the genera Azotobacter and Azospirillium) on sunflower (c.v. Sakha 53) seed yield and quality. The experiment was laid out in a randomized complete block design with three replicates. The experimental treatments comprised partial substitution of the recommended mineral N (MNRec.) rate (30kgN/fed.) with organic N fertilizer (ONF) as compost combined with bio fertilizer. Results revealed that application of T4 (50%MNRec. +25% ONF +Bio) significantly improved yield, as well as yield attributes and protein and oil yields as compared to 100%ONF(T8) or 100%MN(T1) only .The integrated MN with ONF(25-50%ONF)always gave higher values than those obtained with full N rate as mineral or organic only. However, maximum seed oil percentage was recorded, when crop was fertilized by T6 (100%ONF+Bio) followed by T5 (25%MNRec. +75% ONF) while maximum seed oil yield was recorded by T2 (50% MN Rec. +50% ONF) followed by T4 (50%MN Rec. +25% ONF +Bio). According to the results of this experiment, unsaturated fatty acids, mainly linoleic and oleic acids raised in response to the integrated fertilization system while the saturated fatty acid (palmitic and stearic acid) were reduced. High percentages of oleic acids (50.17%) and linoleic acid (45.29%) were observed in T4 and T9. So, bio- organic fertilizer could be considered as a suitable substitute (25-50%) for mineral nitrogen fertilizer in agricultural systems.
Keywords: (Fatty acid composition, Sunflower seeds, Mineral nitrogen, Bio-fertilizer, Organic fertilizer, Oil yield)
