Screening of Salt Tolerant Potato Genotypes using Salt Stress and Molecular Markers

Aims: To screen potato genotypes for salt tolerance using in vitro salt stress and moleulcar markers.

Experimental Design: The experiment was arranged in Completely Randomized Design (CRD) with three replications.

Place of the Study: The experiment was conducted at the Molecular Biology and Tissue Culture Laboratories, Institute of Biotechnology and Genetic Engineering, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur, Bangladesh.

Methodology: In vitro screening of five potato genotypes (CIP 112, CIP 117, CIP 120, CIP 127, and CIP 128) was done in an agar medium using tissue culture technique at different concentrations of salt viz. 0.0, 10, 20, 40, 60, 80, 100, 120 mM of NaCl. All genotypes were further analysed through SSR markers using three primers. The DNA bands were visualized on gel electrophoresis and scored for polymorphic loci, gene diversity, and genetic distance. NTSYSpc program was used for constructing unrooted neighbor-joining tree and scatter diagram.

Results: Potato genotypes CIP 112 and CIP 117 emerged as the most salt tolerant genotypes with the highest plant height, shoot dry weight, root length, and root dry weight at different concentrations of NaCl. CIP 127 and CIP 128 were poorly tolerant to salt stress. The most sensitive genotype CIP 120 produced minimum plant height, shoot dry weight, root length, and root dry weight at different NaCl concentrations. Results indicated that significant differences were found among cultivars. The banding pattern of microsatellite confirmed a distinct polymorphism among salt tolerant, moderately salt tolerant and salt sensitive lines. The clustering pattern of the potato genotypes suggests that variations occur due to genotypic variation and possibly not epigenetic adaptation under salt stress conditions.

Conclusion: The salt tolerant pototo genotypes CIP 112 and CIP 117 can be used for developing salt tolerant genotypes.