Effect of different conservation period with different sucrose concentrations on conserving somatic embryo clusters of date palm (Phoenix dactylifera L.) under minimal growth conditions

Abstract

The present study was conducted to investigate the possibility of using in vitro slow growth storage for date palm germplasm conservation to promote germplasm exchange and rapid propagation when necessary. Multiply somatic embryos cluster of date palm cv. Sukarry were used as conserved explants. Different conservation period 4, 8, and 12 months with different sucrose concentrations at (30, 60, 90 or 120 g/L) supplemented in conservation medium which consist of 1/2 strength of basal salts of Murashige and Skoog (MS) medium, 30 g/L mannitol, 0.05 mg/L (BA) benzyladenin, 0.1 mg/L (NAA) naphthalene acetic acid and 8 mg/L agar, under low temperature at 15 ◦C and dark of incubation conditions, were studied on the survival and re-growth capacity of date palm conserved explants after returning to the normal growth conditions. Contents of total soluble sugar (TSS), non-reducing sugar (NRS) and reducing sugar (RS) were also determined as physiological changes during conservation periods. Results showed that conservation medium supplemented with sucrose at 90 or 120 g/L gave the highest significant value of survival percentage respectively after 12 month of conservation period. Best recovery performance under normal growth conditions for conserved somatic embryos cluster under studied minimal growth conditions was achieved when sucrose at 90 g/L was used in conservation medium for 8 months.