Influence of Desiccation Time on Survival and Regeneration of Embryonic Axes of Groundnut ( Arachis hypogaea L.) Immersed in Liquid Nitrogen

Abstract

Cryopreservation, the storage of biological materials in liquid nitrogen (LN), is a useful method for long term conserva- tion of plant germplasm. This study was carried out with the objective of establishing an efficient desiccation technique for successful cryopreservation and recovery of embryonic axes of groundnut. Embryonic axes of four groundnut (Ara- chis hypogaea L.) genotypes were evaluated. The excised embryonic axes were dehydrated by air current of a laminar air flow cabinet for different duration (0, 1, 2, 3, 4 & 5 hrs) before being plunged in LN (−196˚C) and held for 1 hr. Samples were thawed in water bath at 40˚C for 2 min, thereafter cultured on MS medium supplemented with 15 mg/L BAP for recovery. Highest survival (96.67% - 100%) and shoot formation (91.67% - 96.67%) were obtained at an av- erage moisture content of 17% after 4 - 5 hr desiccation. Among the genotypes evaluated, Samnut 22 and Samnut 23 recorded the highest survival and shoot formation. This technique therefore appears promising for cryopreservation of groundnut germplasm.