Preface

The cultivation of medicinal plants, especially high-value medicinal plants, is creating a new dimension in the field of agriculture. However, the cultivation of medicinal plants is not easy. It is a challenging task because of very little knowledge of seed and pollination biology, nutrient and microhabitat requirements, pest management and growing seasons. Not much effort has been made to search for elite specimens and their propagation.

In recent years, plants in their natural habitat have become rare due to large-scale destruction for medicinal uses, long intervals for vegetative, flowering and fruiting stages, short viability of seeds and low seed germination. It is, therefore, important to conserve these medicinal plants because of their commercial importance. Conventional propagation methods cannot replace the depleting population because the seeds show a low percentage of germination, and vegetative propagation methods are sometimes unsuccessful. The development of standardized micropropagation techniques for the improvement of medicinal plant species is an important issue for preserving biodiversity. Further propagation through seeds may not fulfil the commercial demand of herbals and therapeutically important medicinal species. In vitro culture can be a valuable technique for clonal mass propagation and conservation of these medicinal plants within a short period of time.

Micropropagation, however, is highly labour oriented and, thereby, commercial companies are outsourcing plant multiplication activities to low-labour cost areas. Hence, in technologically advanced countries, the great potential of micropropagation for large-scale plant multiplication can be tapped by cutting down the cost of production per plant, pursued by applying the low-cost tissue culture, adopting practices, and optimizing the use of equipment and resources to reduce the unit cost of micropropagule and plant production without compromising the quality. Furthermore, the development and rapid multiplication of new medicinal plant cultivars are required to meet the demand of the industry all year round. The existing and refined protocols for in vitro culture, as well as their direct applications in improving and developing new cultivars, regularly supply plant material year round. Moreover, in vitro long-term storage of valuable germplasm would immensely provide benefits to both the industry and academic institutes. The outcome of recent studies carried out in various research laboratories and institutions shows optimized micropropagation protocols for many medicinally-important species and well-developed in vitro techniques, such as thermotherapy and cryotherapy for virus-free production, exploitation of somaclonal variation, long-term shoot culture conservation, and plant rejuvenation.

The present book gives the protocols for micropropagation of more than 40 species of medicinal plants. This book smartly combines scientific principles with the state-of-the-art in tissue culture techniques presented by experienced authors. I wish to express my gratitude to all the authors who contributed to the review chapters and research papers. I thank them for their cooperation and erudition. I hope that this will be a sourcebook for the cultivation and improvement of medicinal plants. I request that readers give their suggestions to improve in future editions.