Figure 2.

The profiles of the log likelihood ratios for root number, an adventitious root trait in poplar, across all the 19 linkage groups in the integrated map of P. deltoids and P. euramericana based on (a) test cross, (b) F₂ cross, and (c) full cross models. The threshold values of the three models for asserting the existence of a QTL at a significance level of p = 0.01 are indicated as horizontal dashed lines. Each short red line at the bottom of the frame indicates a marker position.