Journal of food science and technology(Iran)

Journal of food science and technology(Iran)

Impact of Suspended Phosphorus Fertilization and Humic Acid Foliar Application on Quantitative and Qualitative Yield Parameters of Cowpea Tuberous Roots (Vigna unguiculata L.): Implications for Nutritional Quality and Food Processing

Document Type : Original Article

Authors
Duha Ali Jasim
Fouad Abbas Salman
Department of Horticulture and Landscape Engineering, College of Agriculture, University of Kufa, Iraq
10.48311/fsct.2026.119061.83042
Abstract
This study investigated the synergistic effects of foliar-applied suspended phosphorus (SP) and humic acid (HA) on the yield and nutritional quality of cowpea (Vigna unguiculata L. cv. Ramshorn). A factorial experiment arranged in a randomized complete block design (RCBD) with three replicates was conducted. Treatments consisted of four SP concentrations (0, 3, 6, and 9 g L⁻¹) and three HA concentrations (0, 2, and 4mL L⁻¹). Data were analyzed using GenStat software, with means separated by Duncan’s multiple range test at p≤ 0.05. Results demonstrated that SP fertilization significantly enhanced the number of pods and total pod yield. HA application markedly improved pod nitrogen and protein content, alongside increasing pod length and seeds per pod. A significant interaction was observed between SP and HA. The combined treatment of 9 g L⁻¹ SP and 4 mL L⁻¹ HA proved optimal, producing the highest values for key agronomic and quality parameters: pod number (22.00 plant⁻¹), seeds per pod (10.00), pod length (18.16 cm), total yield (7.087 t ha⁻¹), pod nitrogen (3.33%), and pod protein content (20.86%). These findings highlight the efficacy of combined SP and HA foliar application as a sustainable strategy to concurrently boost the productivity and nutritional value of cowpea grains.
Keywords
Suspended phosphorus
liquid organic fertilizer
cowpea plant

Subjects

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