Using Growth Parameters for In-vitro Screening of Potato Varieties Tolerant to Salt Stress

Abstract

Salt stress negatively impacts crops yield througho ut the world. Nine varieties of potato ( Solanum tuberosum L.) were screened for salt stress tolerance by mea suring in-vitro growth of the aerial plant parts, as well as roots. Salt stress was evaluated by adding 25, 50, 75, 100, 125, 150 and 200 mM of NaCl to Murashi ge- Skoog (MS) medium and compared to MS medium without NaCl. Plant length an d stem thickness, leaf area, roots number, length, and thickness, and plant fresh and dry weights were measured. Osmotic pressure ( Ψ medium , MPa) and electrical conductivity (EC medium , mS cm -1 ) of media ranged from −0.2 to −0.91 MPa and 5.8 to 24 mS cm -1 , respectively. Salt stress adversely affected the plant growth, and varieties differed in their r esponses. Progressive reduction in the studied parameters occurred as NaCl levels increase d. Grouping all the varieties by cluster analysis, based on the growth parameters re sponse to salt stress, resulted in three distinct groups: (1) salt tolerant group of two var ieties, namely, Taurus and Sultana; (2) moderately salt tolerant group of four varieties, n amely, Loane, Diamant, Amarin, and Sylvana; and (3) salt sensitive group of three vari eties, namely, Toscana, Soraya, and Kenita. The response variation of these potato vari eties under NaCl indicated the possibility of using them for developing salt toler ant varieties for production in Syria. Keywords: In-vitro culture, NaCl, Salinity tolerance, Solanum tuberosum .