Pengujian daya simpan dan viabilitas lima jenis biji tumbuhan langka: Parmentiera cereifera Seem., Santalum album L., Dillenia philippinensis Rolfe, Reutealis trisperma (Blanco) Airy Shaw dan Joannesia princeps Vell.

Five endangered plant species (Parmentrera cereifera Seem., Santalum album L., Dillenia philipphinensis Rolfe, Reutealis trisperma (Blanco) Airy Shaw, Joannesia princeps Vell.) with recalcitrant seeds were studied to conserve them. The study aimed to determine the viability of the seeds with different storage treatments and their germination behavior. This study was conducted at the seed bank of Purwodadi Botanic Garden by storing seeds for three months, during which the seeds were sown to test their viability every month. Seed germination was done in the green houses at Purwodadi Botanic Garden with three replicates of three seeds to observe their growth. The germination percentage indicates the level of viability of the seeds after being stored for three months. Seeds of D. philippinensis are capable to germinate after being stored at room temperature for one month (55%) and cold temperature for two months (41.67%). Seeds of P. cereifera. can germinate afte three months of storage at cold temperature (70%) or room temperature (56.67%). Seeds of S. album were able to survive in cold temperature and room temperature storage despite of low germination percentage (36.67% and 20%). Similar condition also accurs to J. princeps and R. trisperma, with the seeds of R. trisperma only survives after two months of storage. Storage period and storage temperature greatly affect seed viability of the five endangered plants species.