Effect of Mineral, Bio-Fertilizer and Brassinolide Spraying on The Growth and Oil Percentage of Peanut (Arachis Hypogaea L.)

A field experiment was conducted in one of the agricultural fields located on the right bank of the Euphrates River in Heet District, Anbar Governorate, during the 2022 agricultural season to study the effect of mineral and bio-fertilizers and the growth regulator brassinolide on growth traits and oil percentage of peanut (Arachis hypogaea L.). The experiment was arranged using a Randomized Complete Block Design (RCBD) in a split-plot arrangement with three replications. The main factor included brassinolide spraying stages (no spray, one spray at the beginning of flowering, and two sprays—first at the beginning of flowering and the second at the beginning of peg formation). The sub-factor included fertilization treatments (full mineral fertilizer recommendation, bio-fertilizer only, 25% mineral fertilizer + bio-fertilizer, 50% mineral fertilizer + bio-fertilizer, and 75% mineral fertilizer + bio-fertilizer). The results showed that the full mineral fertilizer recommendation achieved the highest number of branches and leaf chlorophyll content (4.72 branches plant⁻¹ and 41.39 SPAD, respectively). Meanwhile, the treatment with 50% mineral fertilizer + bio-fertilizer recorded the highest values for shoot dry weight and oil percentage (368.9 g and 52.37%, respectively