Significant correlations between the performance of the lines at high and low temperatures were observed for the portion of the primary root on the embryonic root system (r2 = 0.69***) (Fig. 4f), the leaf area/root length ratio (r2 = 0.58*), and the lateral root length (r2 = 0.40*) (Table 2), indicating a low genotype-by-temperatures interaction. In contrast, coefficients of determination close to zero, observed for ΦPSII and the axile root length, indicate a strong genotype-by-temperature interaction. According to the absolute mean values over all the tolerance indices of the lines (Table 2, line TI), CM105 responded most sensitively to temperature (mean change = 69%), while FlH1 responded least (mean change = 23%)