Influence of Zinc Fertilization levels on Growth, Yield and Quality of Some Sunflower Genotypes (Helianthus annuus L.)

The study included two field experiments for (Helianthus annuus L.) conducted during spring growing seasons of 2009, 2010 in two locations. The first Sheikh Mohamed 25km west north Mosul city, the second ones Gueer 50 Km east of Mosul city at Nineveh province .The main objective was to find out effect of zinc foliar application on the growth, yield and quality of some Sunflower genotypes. Each experiment was conducted according to factorial experiment in a randomized completely block design with three replications. Each experiment included three levels of zinc foliar application (0, 5 and 10 mg.L-1) were sprayed on the leaves one dose during 6 leaves stage, with three genotypes of Sunflower crops (Record, Mlabar and Fodak). The genotype Mlabar gave a high level for characters Plant height (161,152 cm), stem diameter(2.06,2.20cm), leaf area index(1.78,1.74), dry weight of the head, head diameter flower disc (21.90 , 22.20 cm), number of seeds/head, weight of thousand seed, total seed yield (2.49, 2.49 ton.hectar-1), oil percentage (43.33 , 44.01 %) and oil yield (1.07, 1.09 ton/ha.) in both locations Sheikh Mohamed and Gueer respectively. The foliar application the zinc to the leaves with concentration 10 mg.L-1 lead to a significant increase in plant high (173.55, 163.63cm), while increasing concentration of zinc to 5 mg.L-1 cause a significant increase in number of leaves/plant, leaf area index, dry weight for flower disc, disc diameter (22.32, 22.87 cm) , number of seeds/head, weight of thousand seed, seed yield (2.73, 2.72 ton.hectar-1) and oil (%), oil yield (1.22,1.24 ton.hectar-1) in Sheikh Mohamed and Gueer locations respectively. The interaction between the genotypes and foliar application was significant in some of growth, yield and quality characters, the Mlabar genotype with zinc application to the leaves with concentration 5 mg.L-1 was superior for head diameter (22.92 , 23.27 cm), thousand seed weight (82.63 , 81.53 g), oil yield (1.33, 1.30 ton.hectar-1) for the Sheikh Mohamed and Gueer locations respectively