EX-SITU CONSERVATION AND MORPHO-BIOCHEMICAL STUDY OF EXOTIC GERMPLASM OF POTATO

To keep potato germplasm disease-free and available for use, it was conserved as In vitro micro-plants under tissue culture conditions using different concentrations of mannitol and sorbitol. Mannitol and sorbitol at 60 g/L effectively reduced growth of explants and kept healthy for 180 days. Whereas explants in Murashige and Skoog (MS) media alone or supplemented with 20-40 g/L of mannitol or sorbitol filled the growing tubes, and had to sub-culture after 110 and 150 days, respectively. Higher concentration of both mannitol and sorbitol (100 g/L) caused complete death of explants. Alike, explants in control treatments had higher chlorophyll while it was comparable in explants conserved in MS media along with 40-80 g/L sorbitol or mannitol Higher proline and less sugar contents were depicted for explants conserved in MS media with 80 g/L of sorbitol compared to mannitol Explants conserved in MS media along with 60 g/L sorbitol had maximum plant condition (4 out of 5) score than same level of mannitol (3.66). Genotype "Karuda" had maximum plant height, leaves and branches in both mannitol and sorbitol than genotype "Burna" and "Asterix". In short, sorbitol and mannitol play a similar role however sorbitol has more beneficial effects than mannitol.