In vitro Germination and Seedling Development of Mangosteen Influenced by GA₃ and Sucrose Levels

Abstract

Mangosteen (Garcinia mangostana L.) is an important tropical fruit crop of the family Clusiaceae, prized for its unique flavour, high market value and medicinal properties. However, large scale propagation of mangosteen is constrained by slow growth, seed recalcitrance, poor rooting and low seedling vigour, making conventional propagation inefficient. The present investigation aimed to standardize the in vitro seed germination and seedling production protocol to enhance seedling vigour. The study was conducted at the College of Agriculture, Vellayani, using freshly extracted mangosteen seeds cultured on Murashige and Skoog (MS) medium of full and half strength each supplemented with varying concentrations of sucrose (1-3%) and gibberellic acid (GA₃: 0.2–1 ppm). The experiment consisted of twelve treatments with three replications. Observations on germination percentage, number of days taken for germination, seedling vigour index (SVI I and II) and growth parameters were recorded after 30 days of inoculation. Significant variations were observed among the treatments for all the parameters studied. The treatment T₁₂ (½ MS + 2% sucrose + 1 ppm GA₃) exhibited the highest germination percentage (95.24%), earliest germination (12.33 days) and maximum vigour indices (SVI I: 1383.81; SVI II: 44.48). This treatment also recorded superior shoot (5.73 cm), root (7.13 cm), and leaf (4.77 cm) lengths compared to other treatments. During hardening plantlets from T₁₂ maintained vigorous growth and achieved 95% survival rate in  coirpith vermiculite mixture confirming successful sucrose concentration and GA₃ supplementation which significantly enhanced in vitro germination, seedling vigour, and survival in mangosteen. The optimized in vitro germination and seedling production protocol offers an efficient method for large scale propagation and conservation of elite mangosteen germplasm.