Annual Research & Review in Biology

Background and Aim: Osyris lanceolata (Hochst. & Steud) is an evergreen shrub or small tree of the Santalaceae family, valued for its fragrant heartwood and essential oils used in perfumery and traditional medicine. However, its propagation is limited due to poor seed germination and challenges in vegetative methods. This study aimed to evaluate the effects of different pre-sowing seed treatments, germination substrates, and fruit maturity stages on the germination and early growth performance of O. lanceolata from naturally growing populations in Tehri Garhwal, Uttarakhand.

Study Design: The study was conducted through two separate experimental setups using a completely randomized design (CRD) to evaluate the effects of fruit maturity stages, germination substrates, and various pre-sowing treatments on the seed germination and early growth of Osyris lanceolata. In the first experiment, conducted at the Forest Tree Seed Laboratory, ICFRE-FRI, seeds collected at three different maturity stages (green, light orange, and bright red) were subjected to mechanical scarification followed by soaking in boiling water for 12 hours. The seeds were then sown on two different substrates: sand and vermiculite, incubated under controlled laboratory conditions at 25 ± 1 °C, >90% relative humidity, and a 24-hour photoperiod. Each treatment included four replicates of 20 seeds.The second experiment was carried out in the nursery of Jakh-Koti Botanical Garden, Tehri, Uttarakhand where seeds were subjected to eight different pre-sowing treatments: T1 – Control, T2 – Mechanical scarification + 500 ppm GA₃ (24 h), T3 – Mechanical scarification + 1000 ppm GA₃ (24 h), T4 – 30% Hydrogen peroxide (24 h), T5 – 0.2% Potassium nitrate (24 h), T6 – 2% Thiourea (24 h), T7 – 20% Sulfuric acid (1 min), and T8 – Hot water (1 min). Each treatment included four replicates of 80 seeds. Across both experiments, germination performance was evaluated using key parameters: Germination Percentage (GP), Mean Germination Time (MGT), Germination Value (GV), Peak Value (PV), Germination Index (GI), Seedling Vigor Index (SVI), Sturdiness Quotient (SQ), Vigor Index (VI) and Quality Index (QI).

Results: In the laboratory experiment, substrate and fruit maturity stage had a significant impact on germination parameters. Seeds sown on vermiculite showed a significantly higher germination percentage (46.66 ± 7.63%) compared to those sown on sand (33.33 ± 7.63%). Pretreatment improved all germination parameters, while fruit maturity stage played a critical role. Seeds collected at the bright red maturity stage (moisture content: 52.62 ± 2.51%) recorded the highest germination percentage and germination value, along with a low mean germination time (MGT), indicating their physiological readiness for germination. In the nursery experiment, the highest germination percentage (66.66 ± 8.32%) was observed in T3 – Mechanical scarification followed by soaking in 1000 ppm GA₃ for 24 hours, which was significantly superior to all other treatments. This was followed by T2 (Mechanical scarification + 500 ppm GA₃; 49.33 ± 4.61%) and T7 (20% Sulphuric acid for 1 min; 41.33 ± 2.30%). The lowest germination percentages were recorded in T4 (30% Hydrogen peroxide; 18.66 ± 2.30%), T8 (Hot water; 18.66 ± 6.11%), and the untreated control T1 (13.33 ± 2.30%), with significant differences among them. Among all treatments, T3 proved to be the most effective for enhancing seed germination. 

Conclusion: The study highlights effective strategies for improving the germination and early growth of Osyris lanceolata. Vermiculite was identified as the optimal germination medium, while seeds collected at the bright red maturity stage (~52% moisture content) exhibited the highest germination performance, including superior germination percentage (GP), germination value (GV), and reduced mean germination time (MGT). Among pre-sowing treatments, mechanical scarification followed by soaking in 1000 ppm GA₃ for 24 hours (T3) resulted in the highest germination percentage and significantly enhanced seedling vigor. These findings provide valuable guidance for optimizing seed propagation and support the domestication and conservation of O. lanceolata.