Combined Effects of Barley yellow dwarf virus (BYDV) Infection and Salinity Stress on Barley Growth and Yield Parameters

Following the current climate changes, Tunisia climate is characterized by less and more irregular rainfall together with milder and shorter winter, resulting in increased soil salinity and higher incidence of Barley yellow dwarf virus (BYDV). The selection of productive cultivars adapted to both abiotic and biotic constraints is crucial for crop breeders, and especially for cereal breeding. In this study, the behavior of two genotypes (G1 and G2) obtained from a cross breeding (QB813- 2/3/Lignee527/NK1272//JLB70-63) and the most commonly grown cultivar Rihane were compared for their responses to the combined effects of various salinity levels (0 to 150 mM NaCl) and BYDV virus infection. Rihane was the most sensitive cultivar under biotic and abiotic stress combination whereas growth and yield parameters were significantly improved in G1 and G2 genotypes under BYDV+50 mM NaCl treatment. In addition, these two genotypes were less affected by the virus infection and high salinity (100 and 150 mM NaCl) combination than Rihane. Interestingly, stress tolerance index was higher in G2, followed by G1 and Rihane, suggesting that this parameter could be a useful trait to discriminate genotypes for their performance under multiple stress conditions.