Quarantine of Germplasm: Safeguarding Genetic Resources Through In Vitro Tissue Culture

The international transfer of beneficial germplasm has played a crucial role in the advancement of agricultural diversification, with around 30% of global food requirements being met by crops of nonnative origin. Crop germplasm has been shared with researchers worldwide for trade purposes, preservation of genetic diversity among nations, and use in programs aimed at enhancing yield and productivity. Quarantine is a strategy imposed by governments through effective legislative measures to prevent the spread of animal or pest-infected crops or pathogenic organisms from one place, region, nation, or group of countries. This is achieved by regulating the import of planting materials, soil, plant-based products, living organisms, etc. The national agencies are responsible for monitoring and executing plant quarantine protocols to protect their natural resources and agriculture from potential damage. When introduced, these measures inhibit the development and proliferation of threats. In this respect, the plant tissue culture approach is extensively used for large-scale multiplication and offers an attractive opportunity for preserving rare genotypes. Tissue-cultured plant germplasm consists of various cell combinations, including growing points, undifferentiated cells, seeds, and complete plantlets, all maintained in a controlled environment that provides the optimal conditions necessary for plant growth and development. The germplasm exchange by means of tissue culture has become an important approach for sharing germplasm in clonally propagated crops (sweet potatoes, potatoes, sugarcane, cassava, and citrus), yet this technology offers several limitations in terms of pathogen detection especially viruses. The plant pathogens can rapidly spread at local and global level if quarantine regulations are not followed strictly as per the norms of world trade organization, and the pest exclusion can be performed by adopting efficient regulatory and technical approaches. Thus, the quarantine system should be strengthened in terms of utilization of preverified disease-free planting material for the import.