Assessing the Role of Spatoglossum aspermum J.Agardh, a Seaweed-Based Liquid Fertilizer in Modulating the Growth and Pigment Composition of Vigna unguiculata (L.) Walp.

Liquid seaweed extracts (LSEs) have garnered significant attention as biofertilizers in recent years owing to their potential role in enhancing agricultural productivity. Seaweed liquid fertilizers (SLFs) are recognized for their rich organic matter and biostimulant properties, demonstrating promising crop growth and yield results. These fertilizers emerge as a sustainable alternative in modern agriculture, capable of improving crop production while minimizing environmental impacts. The present study highlighted the efficacy of <i>Spatoglossum aspermum</i>, on the development, yield, and biochemical parameters of <i>Vigna unguiculata</i>. Phytochemical screening and elemental analysis of the <i>S. aspermum </i>were performed to assess their biostimulant properties. The seeds of <i>V. unguiculata </i>were treated with different concentrations of SLF, and the key physical metrics encompassing the vegetative, reproductive traits, and biochemical parameters were evaluated. The findings indicated that the 20% application of SLF concentration provided noticeable results in pigment concentration [carotenoid content (0.004 ± 0.001), carbohydrates (0.004 ± 0.015), and protein content (0.403 ± 0.152) than control (<i>p</i> < 0.05)], and yield [shoot length (283.16 ± 0.96), root length (12.33 ± 0.57), number of leaves (28 ± 1), fresh weight (88.26 ± 0.75 g) and dry weight of 45.16 ± 1.04 g (<i>p</i> < 0.050)] increasing the overall growth of the test crop. Furthermore, a change in the pH and the moisture-retaining capacity of the soil revealed the underlying substantial contribution of SLF to soil health and fertility.