Cryopreservation of zygotic embryos of Podophyllum hexandrum Royle, an endangered medicinal plant, by vitrification and v cryo-plate techniques.

BACKGROUND Podophyllum hexandrum is a highly endangered valuable medicinal plant of the Himalayas belonging to family Berberidaceae. This plant needs conservation efforts due to the over-exploitation and unscrupulous harvesting from the wild because of its ever-increasing demand. OBJECTIVE To establish a long-term cryopreservation method for Podophyllum hexandrum using two techniques: Vitrification and V Cryo-plate. MATERIALS AND METHODS Zygotic embryos were cryopreserved using vitrification and V cryo-plate by optimization of parameters including preculture time, loading time and PVS2 dehydration time. Recovery of zygotic embryos was performed on different regrowth media for plantlet formation. RESULTS With V cryo-plate, 90% regrowth was obtained as compared to 73.3% with vitrification. V Cryo-plate conditions were pre-culture of zygotic embryos in 0.3 M sucrose for 4 days, treatment in loading solution with 0.8 M sucrose for 20 min, dehydration in PVS2 for 50 min, LN exposure, unloading in 1.2 M sucrose for 20 min and transfer of zygotic embryos to regrowth medium for recovery. During recovery, the maximum number of shoots (4.2) and highest shoot length (5.1 cm) were observed on regrowth medium with 1.5 mg per liter BAP and 0.1 mg per liter IAA (R7). CONCLUSION Zygotic embryos of Podophyllum hexandrum were cryopreserved with 90% regrowth using a V cryoplate technique and plantlets were produced directly after cryopreservation. Doi: 10.54680/fr23410110712.