Overview of Conservation of Microbial Genetic Resources.

Microorganisms constitute a fundamental component of ecosystems and sustain essential services in agriculture, industry, and health. Despite their relevance, it is estimated that less than 1% of global microbial biodiversity has been isolated, cultivated, characterized, and preserved, highlighting a profound knowledge gap. This limitation represents a critical challenge for the sustainable use of these resources, particularly in a context of increasing biodiversity loss driven by anthropogenic pressures. The conservation of microbial genetic resources relies on complementary in situ and ex situ strategies. In situ conservation focuses on protecting natural habitats, maintaining microbial populations in their native environments, and enabling the continuity of evolutionary and ecosystem processes. Moreover, it represents the only approach capable of preserving the majority of still-undescribed microbial biodiversity. In contrast, ex situ conservation involves the preservation of microbial strains and microbiomes in specialized microbial resource centers. Rigorous strategies, such as the adoption of FAIR principles (findable, accessible, interoperable, and reusable), the implementation of standardized quality frameworks (ISO 21710, 9001, 17025, 20387), and compliance with international legal frameworks (such as the Nagoya Protocol and the Budapest Treaty), are globally prioritized to ensure the reliability, traceability, and interoperability of microbial resources. Furthermore, the integration of omics approaches and global databases is transforming how microbial diversity is documented, preserved, and shared. This chapter provides an overview of the conservation of microbial genetic resources, addressing their ecological and biotechnological relevance, as well as current strategies, global challenges, and actions undertaken by international networks.