Evaluation of Salt Tolerance in Commercial and Promising Sugarcane Cultivars at the Beginning of Growth Using Different Stress Tolerance Indices

Sugarcane (Saccharum officinarum L.) is one of the most important sugar crops that provides the major part of consumed sugar of the people worldwide. Because of the excessive demand for sugar and its byproducts, cultivation of sugarcane is expanding rapidly in subtropical arid and semi-arid regions such as south-west of Iran. Salinity is an important abiotic stress that causes reduction in sugarcane yield under saline and sodic conditions of soil and water in Khuzestan province. This study was conducted to evaluate seven commercial and promising sugarcane cultivars at formative stage for different stress tolerance indices and distribution of genotypes and indices in 3-D plots and biplots by using a complete randomized design with three replicates and four salinity treatments (0, 0.25, 0.5, 0.75 % NaCl) in a hydroponics system at research greenhouse of Isfahan University of Technology (IUT). Different tolerance and sensitivity indices for dry weight yield of sugarcane cultivars showed that NCO-310 genotype had high dry matter yielding potential in all stress levels. Also CP82-1592 genotype in medium and high level stress intensities had potential to yield relatively high dry matter and low sensitivity to salinity stress. Based on stress tolerance index (STI) revealed that NCO-310 (a commercial cultivar) and CP82-1592 (a promising line) at all salinity levels were the most tolerant cultivars.