Plant Tissue Culture Techniques for Conservation and Mass Propagation of Rare Medicinal Plants

Abstract

The growing global demand for herbal medicines, coupled with habitat destruction and over-harvesting, has placed immense pressure on many rare and endangered medicinal plants. Traditional propagation methods are often insufficient to meet commercial needs or ensure the survival of these plants in their natural habitats. Plant tissue culture—a branch of biotechnology—emerges as a powerful tool for the conservation and mass propagation of these valuable plant species. This review discusses the core concepts, techniques, and advancements in plant tissue culture, and how they can be leveraged to propagate rare medicinal plants on a large scale.

Plant tissue culture involves the aseptic culture of plant cells, tissues, or organs under controlled conditions on a defined nutrient medium. It includes methods such as micropropagation, organogenesis, somatic embryogenesis, callus and suspension cultures, and synthetic seed technology. These techniques offer several advantages, including the rapid multiplication of disease-free, genetically uniform plants, irrespective of seasonal and geographical limitations. Micropropagation, in particular, has been widely adopted for the clonal propagation of endangered medicinal plants such as Withania somnifera, Nothapodytes nimmoniana, and Rauvolfia serpentina.

Another significant advantage of tissue culture is its potential for ex situ conservation, especially for species with poor seed viability or those that reproduce vegetatively. By storing tissues or propagules under cold or cryogenic conditions (cryopreservation), rare germplasm can be conserved for future restoration programs. Furthermore, tissue culture can aid in genetic improvement through somaclonal variation, in vitro mutagenesis, and transformation, facilitating the development of superior varieties with enhanced yield, active compound production, or resistance to diseases.

Despite its promise, plant tissue culture has limitations. These include somaclonal variations in some protocols, the high cost of setup and maintenance, and the technical expertise required for its implementation. However, continuous innovation—such as the development of bioreactor systems and automated micropropagation units—has significantly reduced these constraints, making tissue culture more accessible and scalable.

This review highlights successful case studies of rare medicinal plants conserved and propagated using tissue culture techniques, reviews the role of regulatory frameworks and germplasm banks, and emphasizes the importance of integrating tissue culture with conventional conservation strategies and local community involvement. The synergy between biotechnology and conservation biology opens new avenues to preserve the phytochemical heritage of rare medicinal plants and ensure sustainable utilization for pharmaceutical, nutraceutical, and cosmeceutical industries.

DOI: 10.8612/38.1.2023.3