Morphological Evaluation of Tabernaemontana divaricata for Its Vegetative and Floral Parameters as a Loose Flower

Abstract

Tabernaemontana divaricata is an important ornamental shrub valued for its lovely white flowers, continuous blooming habit, and potential as a loose-flower crop. Aim: The present investigation was undertaken to evaluate the morphological variability among ten accessions of Tabernaemontana divaricata under the agro-climatic conditions of Kerala and to identify superior accessions for loose flower production, commercial cultivation and future crop improvement programmes. Study Design: The experiment was laid out in a Randomised Block Design (RBD) with three replications, each comprising ten plants. Place and Duration of Study: The study was conducted during 2024–2026 at the Department of Floriculture and Landscaping, College of Agriculture, Vellayani, Kerala Agricultural University, Thiruvananthapuram, Kerala, India. Methodology: Ten accessions of Tabernaemontana divaricata collected from different regions of Kerala were evaluated for important vegetative and floral characters. Observations on plant height, internodal length, leaf length, leaf width and stem girth were recorded at 30 and 90 days after planting (DAP). Floral characters, including bud length, bud diameter, flower diameter, corolla length, 100-bud weight, number of petals, number of inflorescences per branch and number of buds per inflorescence were also recorded. The data were subjected to analysis of variance (ANOVA) to determine the significance of differences among accessions. Results: Significant variation was observed among the accessions for all vegetative and floral characters, indicating considerable morphological variability. Accession A7 recorded the maximum plant height at 30 and 90 DAP (49.33 cm and 61.80 cm, respectively), while A3 recorded the maximum stem girth (21.95 and 29.61 mm), leaf length (11.18 and 12.01 cm) and leaf width (4.89 and 5.90 cm) at 30 and 90 DAP, respectively. Among floral traits, A3 recorded the longest buds (37.33 mm), the highest number of inflorescences per branch (6.20) and the maximum number of buds per inflorescence (16.84). Accession A7 recorded the maximum bud diameter (9.01 ± 0.21 mm), flower diameter (46.53 mm), corolla length (39.67 mm), 100-bud weight (73.33 g) and number of petals (15.10). Analysis of variance revealed highly significant differences (P < 0.01) for all the characters studied. Conclusion: The study revealed considerable morphological diversity among the evaluated accessions of Tabernaemontana divaricata. Accession A3 was identified as promising for enhanced flowering potential, particularly for flower yield-related traits, whereas A7 was superior for floral quality and ornamental attributes. These accessions may serve as valuable genetic resources for breeding, varietal improvement and commercial cultivation of Tabernaemontana divaricata as a loose flower crop under Kerala conditions.