Given the amount of salt used in bread, the answer is no according to The Bread Bakers Guild of America:
Most scientists believe that at 2% of the flour weight or less, salt alone does not significantly alter either the yeast’s gassing power or the bacteria’s acid production. A study measuring the gas production in a fermenting dough has shown that gas production is retarded by only about 9% in a dough containing 1.5% salt (based on the flour weight).
Greg Blonder, a Professor of Design and Product Engineering at Boston University, carried out experiments to see how salt affect yeast, with some nice pictures to show the results:
Summary of the experiments: 1) salt at 3% by weight does not kill yeast and does not change the effectiveness of co2 production by the yeast. 2) Salt does strength the gluten so the dough will rise less (which is probably why many believe that salt retards yeast). 3) Dissolving salt in water prior to mixing helps strength the gluten more than a later dry mix (again, probably why some people though that early mixing damaged/killed/retarded the yeast)
I assume the experiments were carried out using commercial dry yeast, so the result may or may not apply to wild yeast in sourdough starters.