Application of salt tolerance indices for screening barley (hordeum vulgare l.) cultivars

Salinity is a wide-spread problem seriously influencing barley (Hordeum vulgare L.) production, but development of tolerant cultivars is hampered by the lack of effective selection criteria. The objective of this study was to produce screening techniques for selecting salt-tolerant progeny in barley breeding program. Fourteen barley cultivars differing in yield performance were grown in separate experiments under salt stress and non-salt stress conditions in 2008–2009. Eight selection indices including salt susceptibility index (SSI), salt tolerance index (STI), tolerance (TOL), regression coefficient of cultivar yield on environmental index (b), yield index (YI), yield stability index (YSI), mean productivity (MP), and geometric mean productivity (GMP) were calculated based on grain yield under salt and non-salt stress conditions. Results showed that the effectiveness of selection indices in differentiating tolerant cultivars varies with the salt stress intensity. Thus, under moderate salt stress, MP, GMP and STI were more effective in identifying high yielding cultivars in both salt and non-salt stress conditions. Under severe stress, regression coefficient (b) and SSI were found to be more useful in discriminating tolerant cultivars. Breeders should, therefore, take the stress intensity of the environment into account in choosing an index.