Screening of potato germplasm against abiotic stress and molecular characterization by randomly amplified polymorphic DNA analysis

The work was conducted to screen the potato germplasm against salinity and drought condition and for molecular characterization using Randomly Amplified Polymorphic DNA Analysis (RAPD). In order to obtain the resistant source, ten potato genotypes with various geographical origins were screened in vitro using sodium chloride and polyethylene glycol. Genomic DNA was isolated and RAPD analysis was done for variability study in regards to stress tolerance. Differential response was noticed among the genotypes which were found different at DNA level. The genotypes showed the following variable pattern of salinity tolerance: Lal Shil > Cardinal > Hecra > Dheera > Diamant > Raja > Aurinda > Granola > Chamak > TPS-1. Plantlets were grown healthy in control (without PEG) and at 1 or 2.5% of PEG; above this plant growth was found to suffer and tended to lethality. Random primers named as OPB02 TGATCCCTGG, OPB10 CTGCTGGGAC and OPB15 GGAGGGTGTT were used in five replications for the genomic DNA amplification. Variations in the DNA banding pattern of different genotypes which reflects that they are different at gene level had been recorded.