Cryopreservation of Ammodendron persicum Seeds and Evaluation of the Cryogenic Seeds under Laboratory and Greenhouse Conditions, as well as Natural Habitat

Ammodendron persicum (Bunge Boiss.) is a desert shrub specie which grows on sand dunes in few areas in South Khorasan and Sistan-va-Balouchestan provinces in east of Iran. Low distribution and narrow ecological range put this species under threat. Long-term seed preservation via cryopreservation is an important approach to prevent the species from threat and extinction. To evaluate the possibility of long-term preservation of Ammodendron persicumseeds in cryogenic conditions (-196°C) seeds of the species were collected from the natural habitats of the species and, three pre-cryopreservation treatments including PVS2, desiccation, 30% glycerol and control were applied before incubating the seeds under cryogenic conditions. The treated seeds were incubated in LN (-196°C) for periods of 1 week and 1 month. Subsequently, the cryopreserved seeds were moved from the liquid nitrogen out and, seed germination and establishment were evaluated under laboratory and greenhouse conditions, as well as natural conditions in Rig-Boland sand dunes in Kashan. Results showed that seeds of the Ammodendron persicum are able to tolerate cryogenic conditions. Effects of the cryopreservation pre-treatments including 30% glycerol and PVS2 were significantly different from that of desiccation. The desiccation pre-treatment showed the best effects on survival rate and other attributes of the cryopreserved seeds. The results showed that the treated seeds are able to germinate and establish in desert sand dunes. In this study, the appropriate seeding depth, the seeding area, factors affecting the seed germination and establishments, as well as other attributes of Ammodendron persicum were evaluated. The results obtained from the present study revealed that cryopreservation is the most promising method for long-term preservation of the Ammodendron persicum seeds.