Unveiling the Impact of Plant Growth Regulator Infused Tamarind Seed Polysaccharide (TSP) Polymer Coating on Seed Quality Behaviour of Cowpea var. VBN 3

Abstract

A laboratory experiment was conducted in 2023 at the Department of Seed Science and Technology, Tamil Nadu Agricultural University, Coimbatore, to evaluate the effectiveness of Tamarind Seed Polysaccharide (TSP) polymer as a natural alternative to synthetic seed coatings for improving the planting value of cowpea seeds. The treatments included T₀ – Control, T₁ – GA₃ 10 ppm, T₂ – GA₃ 20 ppm, T₃ – GA₃ 30 ppm, T₄ – GA₃ 40 ppm, T₅ – GA₃ 50 ppm, T₆ – BRs 0.5 ppm, T₇ – BRs 1.0 ppm, T₈ – BRs 1.5 ppm, T₉ – BRs 2.0 ppm, and T₁₀ – BRs 2.5 ppm. Data were analyzed statistically using a Completely Randomized Design (CRD) with ANOVA. Significant differences were observed among the treatments for all seed quality parameters. Seeds coated with TSP polymer enriched with 3 mL of 1.0 ppm brassinosteroids (T₇) recorded the highest speed of germination (36.96), germination percentage (94%), root length (20.66 cm), shoot length (23.58 cm), vigour index I (4159), and vigour index II (58). In contrast, the uncoated control seeds exhibited the lowest performance in terms of speed of germination (33.74), germination percentage (88%), root length (17.85 cm), shoot length (20.63 cm), vigour index I (3386), and vigour index II (52). The findings indicate that cowpea seeds coated with 8 g of TSP polymer infused with 1.0 ppm BRs exhibited superior germination and seedling vigour compared to other treatments. Hence, this formulation can be recommended as an eco-friendly, biopolymer-based pre-sowing seed treatment suitable for organic agricultural systems.