Alleviation strategies of seed dormancy for conserving important medicinal plant diversity of western Himalaya

Abstract One of the major challenges in medicinal plant cultivation is seed dormancy which occurs more frequently in wild plants than crop plants. Seed dormancy enables seeds to endure periods that are unfavorable for seedling establishment. It may arise due to many factors like impermeable seed coat to water and oxygen, rudimentary and dormant embryo and germination inhibitors. Multiple mechanisms are known to be involved in the induction of dormancy and the transition from dormant to germination. Scarifications, stratification, chilling are some of the important ways to overcome different types of dormancy. Saussurea costus, Inula racemosa, Sinopodophyllum hexandrum and Bunium persicum are some of the important endangered medicinal plants of western Himalaya. These medicinal plants are in great demand in the pharmaceutical industry. These medicinal plants grow under diverse agro-climatic conditions of the western Himalayas’ sub-temperate and dry temperate regions. Overharvesting of these medicinal plants from their natural habitat has resulted in the extinction of their population. Poor seed germination is one of the major limiting factors for their ex-situ conservation and large-scale cultivation. This review explores the mechanisms involved in the seed dormancy and their alleviation strategies. Considering the findings, these dormancy alleviation methods can be applied to cultivate these medicinal plants successfully in the western Himalayan region.