Ca2+spiking patterns induced by fungal and rhizobial signals. Two representative examples of CaSA output files are presented following treatment with CO4 (A), G. margarita spore exudate (B) or Nod factor (C). Values on the Y axis represent the ratio of YFP to CFP fluorescence. The asterisk in B indicates an irregularly-shaped peak where the second rounded maximum is excluded from the CaSA computation. This is a typical case where manual peak identification would be uncertain, while automated analysis represents a reliable and repeatable method.