Fig. 3.

The mean number of CO per individual. For each cross-type, the mean number of CO events was calculated for each individual (top panel) and for each chromosome and each individual (all other panels). CO events were only detectable for the hybrid (Ler-Col) parent, not the Col-0 parent, and therefore represent either events that occurred on the paternal side (blue bars) or the maternal side (red/pink bars) only. Since each meiosis produces four gametic cells and each CO event can only be detected from two of the four gametes, the average number of CO per chromosome per individual indicates only half of the CO events formed in each meiosis. For each cross type and chromosome, the mean and SE are represented. Within a cross type and a cross direction, significant differences between the means were tested on a pair-wise basis using Student's t-test. Significant comparisons are indicated as follows: ***: P value <0.0001, **: P value <0.01, *: P value <0.05. Lack of significance level between two specific means indicates that the comparison was not significant.