Effect of osmotic regulators on In vitro conservation of grape
Some of grape varieties are being vanished owing to genetic drift, bad agronomic practices and short of conservation strategies. Biotechnological strategies have been developed as an alternative and ancillary method. So, the objective of this study was to find out a medium-term conservation protocol of grape (Vitis vinifera L. var. Black Matrouh) and molecular identification of the conserved cultures. The medium term conservation study was initiated at 5°C under complete darkness conditions using In vitro grown nodal cutting explants. Explants were subjected to different osmotic regulators (glucose, mannitol or sorbitol) at different concentrations (0, 0.5, 1.5, 2.5, 3.5, 4.5, 5.5, 6.5, 7.5, or 8.5% (w/v)) which added to ¾ MS basal medium without growth regulators. Results concerning the effect of different conservation periods indicated that survival percentage decreased gradually with increasing the conservation period gradually from 3, 6, 9 to 12 months. Up to 77.78, 77.78 and 88.89% of nodal cutting explants remained green and healthy when conserved for 12 months on conservation medium with 3.5 or 4.5% glucose, 2.5% mannitol and 5.5% sorbitol, respectively. Results regarded recovery and regrowth cleared that regeneration percentage, number of shoots per explant and their length (cm) decreased with increasing conservation period from 6 to 12 months. Determination of stability was performed by assessment of Inter Simple Sequence Repeat amplification (ISSR). The analysis of ISSR markers did not show any variation among the conserved and non-conserved material with the primers used.