Genotypic variation in response to salinity in a new sexual germplasm of Cenchrus ciliaris L.

•Two new sexual resources showed variability in response to salinity.•Salt-treated hybrid 1-9-1 did not suffer oxidative damage and proline did not vary.•Hybrid 1-7-11 suffered oxidative damage and accumulated proline.•Hybrid 1-9-1 had the highest germination rate index at maximum salt concentration.•Neither sexual hybrid decreased its productivity at 300 mM NaCl.

As part of a breeding program for new salt-tolerant sexual genotypes of Cenchrus ciliaris L., here we evaluated the salt-stress response of two new sexual hybrids, obtained by controlled crosses, at seedling and germination stages. A seedling hydroponic experiment with 300 mM NaCl was performed and physiological variables and growth components were evaluated. While salt-treated sexual material did not show a decrease in productivity with respect to control plants, a differential response in some physiological characteristics was observed. Sexual hybrid 1-9-1 did not suffer oxidative damage and its proline content did not differ from that of control treatment. By contrast, sexual hybrid 1-7-11 suffered oxidative damage and accumulated proline, maintaining its growth under saline stress. At the germination stage, sexual hybrid 1-9-1 presented the highest Germination Rate Index at the maximum NaCl concentration assayed, suggesting an ecological advantage in this genotype. These new sexual resources are promising maternal parental with differential response to salt and could be incorporated in a breeding program of C. ciliaris in the search of new genotypes tolerant to salinity.