Cryopreservation for Long-term Plant Germplasm Storage

Abstract

Germplasm is a source of genetic diversity that is essential for sustained through the long term. Seeds germplasms storage that are not resistant to desiccation can be carried out by cryopreservation. Cryopreservation is a method of storing the plant material in liquid nitrogen ( -196oC) so the metabolic processes in cells, tissues or organs that are stored can be stopped so the plant material can be stored in a very long time without a genetic change or somaclonal variation. Cryoprotectants in cryopreservation storage is needed for plant material protection to adapt to the very low temperature. Some examples of successful treated-plant for cryopreservation are cocoa and papaya. In cocoa, proembryo somatic derived from cryopreservation cocoa zygotic embryo can creating embryos survived and were able to grow a callus back as much as 46.67% is dimethylsulfoxide (DMSO) and glycerol with a concentration of 15% each in MSO solution, at a temperature of thawing (melting) 35oC by using culture media such as media restorer MS + picloram 0.1 g L-1 + thiamin 0.2 g L-1 + IAA 1 g L-1 + kinetin 0.1 g L-1. In Sukma papaya seed varieties treatment with cryoprotectants of PVS2 submersion for 30 minutes and the rate of 11 -13% water content provides the best germination value (DB), the maximum growth potential (PTM), and the better rate of growth (KCT), 38.39%, 38.39%, and 2:24%, respectively.