Cryobase establishment of Indian almonds using embryonic axes

Abstract

Almond, Prunus dulcis is one of the most commercially important nut crops of temperate hilly regions of India. Indian states of Jammu and Kashmir, Himachal Pradesh and Uttaranchal have been cultivating several landraces, seedling selections, and wild types and cultivars, both indigenous and exotic since long which need protection as a safety back to field gene banks. Morphological characterization using seven carpological characters among selected 25 almond cultivars of the three states were done to estimate genetic variability and establish genetic relationships of indigenous and exotic cultivars. High morphological variability (86%) among the cultivars/selections of almonds were observed. Almond seeds are characterized by poor germination due to low viability, dormancy and sensitivity to subzero temperatures were cryobanked using embryonic axes (EA) for cost effective conservation. After cryo exposure of 48h, the EA viability ranged from 79 to 100% with 36% of the accessions retaining viability between 95 to 100%. A 240 accessions with 3.5 to 6 percent moisture levels have been successfully cryostored. Evaluation of EA viability for durations of up to 15 years of cryostorage ascertained the applicability of the developed protocol for diverse almond germplasm with retention of original high viability and successful transfer of plantlets to field.