Effects of salt concentration on bacterial growth on plates with gradients of pH and temperature.

A temperature gradient device has been used to produce pH-temperature gradient plates. The response of Salmonella typhimurium and Bacillus cereus to continuous gradients of pH and temperature has been mapped. A third variable, sodium chloride, was investigated by incorporating it at different concentrations in a series of gradient plates. Both organisms exhibited an optimum temperature and pH range for maximum salt tolerance.