Overview of the Success of In Vitro Culture for Ex Situ Conservation and Sustainable Utilization of Endemic and Subendemic Native Plants of Romania

Romania has a relatively high diversity of plant species, including 3829 vascular and 979 non-vascular spontaneous plant taxa (species and subspecies). Due to uncontrolled harvesting as well as other causes, including climate change and ecological collapse, the speed of species extinction and the narrowing of the genetic base of plant resources has been reported as a critical issue. Therefore, the national Red List of Romanian flora includes 1453 threatened taxa, of which 95 are endemic and 90 subendemic. Many of these have high ornamental, medicinal–cosmetic, and/or aromatic properties. The high extinction risk of these valuable plants has stimulated both the reconsideration of their vital importance as genetic resources and interest in finding effective methods for conservation. Cultivating these phytogenetic resources in a human-controlled environment is of high importance for effective ex situ conservation, which can further serve sustainable exploitation needs and may facilitate in situ conservation actions. In vitro culture is a powerful tool for producing elite plants for cultivation for different purposes. This review summarizes the current knowledge on in vitro multiplication of 22 endemic and subendemic native plants of Romania, examining the materials used, the treatments applied, and the results obtained in each stage of the micropropagation protocol (culture initiation, proliferation, rooting, and acclimatization). The findings from the reviewed studies are presented in a comparative way, and the potential of plant tissue culture in conservation and sustainable exploitation of these Romanian species is outlined.