Evaluation of barley cultivars for their tolerance to salinity under field conditions for utilization to saline soils

Soil salinity and water deficit are the most important abiotic factors affecting crop yield in many areas of the world and causing major reduction in crop yield. Therefore, it is important to find better breeding tools for the evaluation of germplasm under drought and salinity conditions which can contribute significantly to increasing crop yields in salt-affected areas. Barley (Hordeum vulgare L.) is one of the most important cereals with great adaptability because of the many genotypes and its tolerance to salinity. During the 2011/12 growing season 200 barley cultivars from different countries and also including new and older ones were evaluated under two levels of salinity (0 or 150 mM NaCl) and two levels of water (40% or 80% of soil water capacity) under controlled conditions. The evaluation took place using agronomic (grain yield, harvest index and yield components) and physiological characteristics (gas exchange parameters: (assimilation rate (A), transpiration rate (E), stomatal conductance (g(s)), intercellular CO2 concentration leaf (c(i))), chlorophyll meter readings, and chlorophyll fluorescence). Following 16 cultivars representing seven (7) tolerant, three (3) sensitive and six (6) moderately tolerant cultivars were grown under two soil salinity levels in the field for two growing seasons (2012/13 and 2013/14) in order to determine their tolerance under field conditions. A number of different characteristics were used to determine the level of tolerance (gas exchange parameters: (assimilation rate (A), transpiration rate (E), stomatal conductance (g(s)), intercellular CO2 concentration leaf (c(i))), chlorophyll meter readings, chlorophyll fluorescence, discrimination of C isotopes, grain yield, harvest index and yield components). In addition, carbon isotopes discrimination showed that tolerant cultivars had higher Delta values compared with the sensitive cultivars to salinity. These data show that there is considerable genetic variation in barley cultivars that can be used to utilize saline soils. Acknowledgements Work co-financed by EU (ERDF) and Greek funds through the program code ARCHIMIDES (C) 2015 The Authors. Published by Elsevier B.V.