Effect of gibberellic acid- and water-based pre-soaking treatments under different temperatures and photoperiods on the seed germination of Allium stracheyi Baker: An endangered alpine species of Central Himalaya, India

摘要

Allium stracheyi Baker (Alliaceae, 2600-3000m asl), an endangered species of Central Himalaya, India, has low seed germination in its natural habitat. This study is an attempt to improve seed germination by determining the seed viability with a low mean germination time (MGT) and germination index (GI) under optimum temperature, light, and pre-soaking treatments. The seeds were pre-soaked in hot water (80 degrees C), cold water (10 degrees C), and gibberellic acid (GA(3) at 50 and 100mg/l) for 24h and subjected to light (12h light and 12h dark) and continuous dark (24h) conditions with different temperature regimes (10, 15, 20, 25, and 30 degrees C). The viability varied between 66.0% and 69.67% and declined rapidly after 12months of storage. Our studies suggest that the 100mg/l GA(3) treatment was beneficial for seed germination and seedling growth. Pre-soaking in a 100mg/l GA(3) solution and incubation at 20 degrees C under light conditions enhanced the germination significantly (p<0.05) and resulted in the highest (97.3%) germination with the lowest MGT=5.7 days, with GI=8.11. The recommendations of this study support the conservation of alpine A. stracheyi via simple and cost-effective techniques for optimal seed germination.