Effect of Pre-sowing Treatments on Seed Germination and Early Seedling Growth of Hildegardia populifolia (DC.) Schott & Endl., a Near-threatened Medicinal Tree Species

Abstract

Background: Pre-sowing treatments are widely recognized for improving germination by overcoming physical dormancy and enhancing seedling vigor in forest tree species. Aims: The study aims to evaluate the Effect of Pre-Sowing Treatments on Seed Germination and Early Seedling Growth of Hildegardia populifolia (DC.) Schott & Endl., a Near-Threatened Medicinal Tree Species.” and to identify suitable techniques for large-scale propagation and conservation. Study Design: Completely Randomized Design (CRD) with eight treatments and three replications. Place and Duration of Study: The study was conducted at Nursery Unit, Department of Forest Biology and Tree Improvement, Forest College and Research Institute, Mulugu, Telangana, India, between 2022 and 2025. Methodology: Fresh mature seeds were collected from natural populations of Chekrayapeta forest, Andhra Pradesh, India. Seed viability was assessed using Tetrazolium (TTC) and water flotation tests. Seeds were subjected to eight pre-sowing treatments: water soaking (24 h), GA₃ (500, 1000 and 1500 ppm), H₂SO₄ (25%) scarification (2 min), cow dung slurry (24 h), cow urine (24 h), and untreated control. Fifteen seeds per treatment with three replications were sown in polybags containing red soil, black soil, and sand (2:1:1) supplemented with cocopeat. Germination parameters and seedling growth attributes were recorded at 45 and 90 days after sowing. Results: Pre-sowing treatments significantly influenced germination and seedling growth. Water soaking for 24 hours recorded the highest germination (60.00%), germination energy (53.33%), and survival (46.66%) with a germination period of 9 days. Seedlings from this treatment showed superior growth at 90 days with maximum root length (19.16 cm), shoot length (39.43 cm), collar diameter (4.91 mm), and number of leaves (24.50). Cow dung slurry produced moderate results, whereas GA₃ (13.33–26.66%) and acid scarification (20.00%) were less effective. Control recorded the lowest germination (6.66%). Conclusion: Seed dormancy in H. populifolia is mainly physical and can be effectively overcome through hydropriming. Water soaking for 24 hours is a simple, economical, and eco-friendly technique that significantly improves germination and seedling vigor, making it suitable for large-scale propagation and conservation programs.