With the support of the National Basic Research Program of China and the Guangdong and Guangzhou Sci-Tech Planning Projects, Prof. REN Hai and his colleagues of South China Botanical Garden have studied the conservation and reintroduction requirements of Primulina tabacum Hance, a rare and endangered plant in China.

Primulina tabacum Hance is a calciphilous perennial herb, with the distribution restricted at the entrances of a small number of Karst cave drainages in southern China. To conserve and evaluate possible reintroduction, we studied its historical distribution, conducted filed surveys of the biotic and physical environments, and reintroduced P. tabacum to its historical and original habitats. Results show that of the eleven historical distribution sites of P. tabacum, three have disappeared. P. tabacum has special ecological requirements, including alkaline soil, low soil content of N, P, K and organic matter, low light, high soil water content and high relative humidity, and a high atmospheric CO2 concentration. By bio-technology, we established an efficient propagation system via somatic embryogenesis and shoot organogenesis and plant regeneration system for P. tabacum. Re-introduction of P. tabacum into the historical habitats is successful, but the survival rate is low. Meanwhile, the transplanted P. tabacum seedlings grew slower than the wild ones.

The moss species, Gymnostomiella longinervis could be useful as a nurse plant species and facilitates the reintroduction of P. tabacum into wild habitats. Currently, the results of these studies have been published in Plant Ecology, Plant Species Biology, and Biologia Plantarum.