Advancing conservation through micropropagation: global patterns, biases, and gaps in protocol availability for timber tree species

Abstract Trees are essential ecosystem components and key economic resources in the Global South. However, nearly one-third of world’s tree species face extinction, and many timber species are overexploited. Micropropagation is a valuable tool for the ex situ conservation of endangered plants, especially for those with recalcitrant seeds or difficult-to-propagate species. However, its application is often limited. We present the first global assessment of micropropagation protocol availability for 4930 IUCN-listed timber species, analyzing patterns across biome, taxonomy, geography, and conservation status. For species endemic to the Global South, we examined protocol details such as species selection, funding, and subsequent plant use. Results reveal pronounced geographic and taxonomic biases which hinder effective conservation efforts. We found studies for only 674 species (13.7%), with higher proportions in temperate areas (55%) and the Global North (41.5%) vs. wet tropical biomes (6.4%) and Global South countries (7.4%). Least Concern taxa comprised the highest study proportion (17.8%). However, Critically Endangered to Data Deficient taxa in the Global North had greater protocol availability (42.6%) than those in the Global South (6.0%). Despite high propagation success, Global South research often prioritizes economically important or introduced species, with few threatened or exceptional taxa included. Most protocols were publicly funded and lack reporting on subsequent plant use. We explore strategies to strengthen the role of in vitro propagation in biodiversity conservation, including species prioritization, linking in vitro work with field projects, North–South collaboration, using ex-situ collections as source material, and structured planning with key stakeholders such as foresters.