Fig. 1.

Spontaneous non-self fusion via CATs occurs frequently between “incompatible” strains of V. dahliae under starvation. a Wild-type strains used in this experiment and their VCG classification. Single-letter strain codes (in brackets) denote derivative strains expressing sGFP- or mCherry-tagged histone H1 (details in Additional file 1: Table S1). The structure of the dendrogram reflects the phylogenetic relationships of VCGs as these were previously determined [39]. b Examples of CAT-mediated fusion between conidia/germlings of strains c-d (originating from the same wild-type strain), c–e (members of VCG 2B) and c–g (“incompatible” members of VCGs 2B and 4A, respectively). Bars = 5 μm. c Frequencies of intra- and inter-strain fusion in pairings of V. dahliae strains a–i. Control combinations indicated with an asterisk involved strains originating from the same wild-type strain. Each pairing was tested in triplicate, and 250-300 fusion events were analyzed per replicate. Bars = standard deviation (SD)