Chemical Treatments to Improve Seedling Emergence and Vigour using Seeds from Six ex-situ Source in Swertia chirayita, a Critically Endangered Medicinal Herb in Himalaya

摘要

Swertia chirayita (Gentianaceae), a critically endangered medicinal herb in Himalaya, is recommended at the top amongst other prioritized species, for its conservation through ex-situ cultivation by an international forum of experts. We examined the effects of identified pre-sowing chemical treatments on seedling emergence and vigour using seeds obtained from ex-situ raised plants under natural conditions (4 sources) and nursery conditions (2 sources), with an aim to fulfill ever increasing demand ofthe pharmaceuticals, and to support in-situ species recovery programme. Seedling emergence was promoted from 6% (control) to 69% (GA_3 250 mu M). The seedling emergence rate was faster in GA_3 (250 mu M) followed by NaHClOj (5 min) in all the seed sources. MANOVA indicated significant effect (p < 0.0001) of treatments on all seedling emergence variables; seed sources and treatments had significant (p < 0.0001) effect on different seedling growth parameters. Collar diameter appeared as the strongest morphological trait, which can be used in identifying vigorous seedlings for plantation.