Impact of some agricultural treatments on the growth characteristics and yield of broccoli

Abstract

SUMMARY: To optimize broccoli growth and productivity, a field experiment was conducted during the 2024 autumn growing season in sandy loam soil at the vegetable research field of the Department of Horticulture and Landscape Design, College of Agriculture and Forestry, University of Mosul, Iraq. The study evaluated the physiological and agronomic impacts of a nano-fertilizer (N₂₀P₂₀K₂₀) applied at four concentrations: 0 g·L⁻¹ (control), 1 g·L⁻¹, 2 g·L⁻¹, and 3 g·L⁻¹. Two methods of fertilizer application were adopted: soil application and foliar spraying. The Nano-fertilizer was applied at three different stages of plant growth: two weeks after transplanting seedlings, two weeks after the first application, and at the beginning of head emergence. This resulted in a total of eight factorial treatments (2 x 4), which ere applied in a factorial experimental design structured within a randomized complete block design (RCBD) with three replicates.

The statistical analysis of the data was performed using the SAS software, and the results were evaluated at a 5% probability level using Duncan's multiple range test. The findings revealed the following:

The use of Nano-fertilizer markedly enhanced foliar chlorophyll levels and significantly increased leaf count per plant. Additionally, it reduced the number of days required for 20% of the broccoli heads to reach maturity and be ready for harvest, with most concentrations showing significant improvements compared to the control treatment. Moreover, each concentration of Nano-fertilizer demonstrated statistically significant improvements across all evaluated yield metrics compared to untreated plants.

In terms of application methods, soil application of the Nano-fertilizer demonstrated a significant advantage over foliar spraying, particularly in terms of average head weight and total head yield per unit area. Most of the interactions between Nano-fertilizer concentrations and application methods aligned with the individual effects observed for each factor across all traits studied.

These results highlight the potential benefits of Nano-fertilizer in improving broccoli growth and productivity, particularly when applied to the soil.