The Effect of Combining Chemical Fertilizer and Livestock Manure on Some Agronomic Characteristics and Quality of Sunflower Seed Oil in Different Tillage Systems

In order to investigate the effect of tillage systems and the combination of chemical fertilizer and livestock manure on some characteristics of sunflower, an experiment has been conducted as split plots in a randomized complete block design with three replications at the research farm of University of Zabol during 2019. The main factor has been tillage levels (1. moldboard plow and disc, 2. sweep and disc, and 3. disc). The sub-factor include fertilizer levels (no fertilizer application, 100 kg/ha of diammonium phosphate, 25 tons/ha of livestock manure+ 100 kg/ha of diamonium phosphate, 50 tons/ha of livestock manure + 100 kg/ha of diamonium phosphate, 25 tons/ha of livestock manure, and 50 tons/ha of livestock manure). Results show that the highest values belong to the 50 tons/ha of livestock manure in tillage with disk for grain yield (5072 kg/ha), and oil percentage (44.44%), 50 tons/ha of livestock manure in tillage with disc for oleic acid content (51.61%), and 50 tons/ha of livestock manure for linoleic acid content (31.1%). The highest amount of chlorophyll a, b and carotenoids (1.253, 0.45, and 1.04 mg/g, respectively) has been obtained from the application of 100 kg/ha of diamonium phosphate in tillage with disc. In general, in order to increase and improve the quantitative and qualitative characteristics of sunflower, the application of 50 tons/ha of livestock manure is suitable in disc tillage conditions.