Frequency (A) and magnitude (B) of SSR expansions/contractions in cucumber genotypes Gy14 versus 9930 in relation to the number of repeat units of the microsatellite. The allele from cucumber inbred line 9930 was considered as the reference (or initial state) of the repeat. For each class of 'number of repeat units', the percentage (bars) and actual counts (italic numbers) of SSRs showing expansions or contractions in Gy14 are presented in panel A. The magnitude of the change in allele sizes (∆al) from 9930 and Gy14 is presented in panel B (error bars denote standard deviations). For compound SSRs, repeat units in each uninterrupted repeat were summed if the allele had at least 10 repeat units (e.g., (AT)8(GT)12 = 20 repeat units).