Effect of Foliar Spraying with Nano NPK Fertilizer, Liquorice Extract, and Organic Nutrient Solution on the Growth and Productivity of Khastawi olive Plants
摘要
The experiment was carried out on a farmer’s olive orchard in the Ramadi Island region from March to November during the 2023–2024 growth season. The objective was to assess the impact of NPK Nano-fertilizer application at concentrations of 0, 1.5, and 3 g L−1, liquorice extract application at concentrations of 0, 5, and 10 g L−1, and organic nutrient solutions at concentrations of 0, 5, and 10 ml L−1 on the growth and yield of 13-year-old Khastawi cultivar olive trees. The experiment used a factorial design with three components, using a randomized complete block design (RCBD) and consisting of three replications. The findings demonstrated a marked superiority of the research criteria, whether assessed singly or in combination. Using Nano-fertilizer at a concentration of 3 g L−1 significantly improved leaf size, chlorophyll levels, and the amounts of nitrogen, phosphorus, and potassium, as well as the average weight of the fruit and total yield during both research seasons. The use of liquorice extract significantly enhanced all examined features in both seasons. Likewise, the use of an organic nutrient solution led to a substantial improvement in all examined parameters over both seasons. The two-way and three-way interactions shown a substantial benefit in the majority of examined attributes.