Effects of Litter and Seed Position on Seedling Establishment of Gentiana dahirica Fischer

摘要

In recent three decades the medicinal plant Gentiana dahurica Fischer has been threatened by large scale exploitation for trade and land-use practices, such as over-grazing and reclamation. However, research into the population ecology and sustainable use of this highly-threatened medicinal plant is lacking, and so we analyzed the effects of different litter applications and seed positioning (surface-sown or buried) as part of a program to rehabilitate it. The results indicated that although litter and seed position per se had no significant effects on the seedling emergence of G. dahurica , interestingly, litter application did show positive effects on seedling survival, e.g. 100 g m -2 and 200 g m -2 litter increased it by 9.7% and 16.4%, respectively, compared to control. Moreover, the seedling leaf area increased with the quantity of applied litter when seeds were surface-sown, with the highest leaf area occurring in the 200 g m -2 treatment (9.7-fold of the control), and litter-covered treatments also significantly improved seedling root length and root diameter of G. dahurica compared to controls. Taken together, these data indicated that seedling establishment of G. dahurica benefited from accumulated litter, and it is thus suggested that fencing to exclude grazing for a period is the best method to protect and rehabilitate the threatened wild G. dahurica populations.