Work

Optimizing phosphorus management in canola (Brassica napus L.) through integrated soil, foliar, and fertigation applications under greenhouse conditions

Year: 2026

Type: article

Abstract: Purpose: This study evaluated the effectiveness of foliar spray and fertigation using phosphoric acid combined with soil application of triple superphosphate (TSP) on growth indices and phosphorus uptake in canola grown under low available soil phosphorus. The experiment was conducted in phosphorus-deficient soil (1.6 mg P kg⁻¹), using a factorial arrangement in a completely randomized design with three replications. Methods: Treatments included four levels of soil-applied TSP (0, 10, 50, and 100% of required P based on soil test) as basal fertilization, foliar sprays using phosphoric acid (0 and 0.5%), adjusted for pH, applied at two growth stages: 4–5 leaf (BBCH 14–15) and stem elongation onset (BBCH 30). Fertigation with phosphoric acid (0 and 10 kg ha⁻¹) was conducted at the 4–5 leaf and rosette stages (prior to BBCH 50). Results: At 0% basal TSP, fertigation increased shoot dry weight by 92% compared to untreated plants, while foliar spray showed no significant effect. With 10% basal application, foliar spray enhanced shoot dry weight by 14% and P uptake by 43%. Combining 50% basal TSP with foliar spray improved agronomic phosphorus use efficiency by 10% and shoot P uptake by 30% compared to no foliar application. Moreover, the combination of 50% basal soil application, foliar spray, and fertigation produced results comparable to those of the optimum 100% soil application without fertigation and foliar spray. A significant positive correlation (R = 0.735) was found between shoot P concentration at pre-flowering and shoot dry weight. Conclusions: The integrated use of phosphoric acid via foliar spray and fertigation successfully met the crop's phosphorus requirements, allowing a 50% reduction in basal soil phosphorus fertilizer without compromising growth. This approach supports sustainable phosphorus management in canola production.

Source: Scientific Reports

DOI: 10.1038/s41598-026-70197-y

Authors: Catherine Shams Moorkani, Hossein Mirseyed Hosseini, Fereydun Nourgholipour, Arzhang Fathi Gerdelidani, Hassan Etesami

Institutions: University of Tehran, Agricultural Research & Education Organization

Language: English

Topic: Agricultural Science and Fertilization

Subfield: Soil Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDG: Zero hunger

Open Access status: gold

Estimated APC paid: $2,690