Effect of Different Levels of Organic and Phosphate Fertilizers on Yield and Quality of Three Sunflower Genotypes (Helianthus annus L.) in Northern Iraq

Abstract

A field experiment was carried out in the semiarid region of Talkif district, which is 35 km north of city of Mosul within Nineveh Governorate, during two growing seasons 2019-2020 and 2020-2021 in sandy loom soil to study effect of three levels of organic manure (0, 400 and 800 kg.ha-1), a form of sheep manure, mixed thoroughly with the soil before planting, and three levels of phosphate fertilizers (0, 75, 150 kg ha-1 P2O5) added at once during soil preparation on yield and quality of three sunflower genotypes (Isera, Melabour and Velko). The experiment was carried out using a multifactorial randomized complete block design with three replicates for each experiment. Results indicate: effect of organic fertilizer was significant on all studied traits for both seasons. The treatment by adding organic fertilizer to soil with the amount of 800 kg.ha-1 gave the highest rate compared to addition of lowest ratio (400 kg.ha-1) and comparison treatment. Since Iraqi soil is poor in its content of phosphorus, which ranks second among the three most beneficial elements for plants, the addition of this element to soil at a rate of 150 kg.ha-1 led to a significant increase in all growth, yield and quality traits for both growing seasons. The genotypes of sunflower crop were significantly affected in all growth, yield and quality traits for both planting seasons. The Melabour genotype surpassed Velko and Isera genotypes in the studied traits for both growing seasons.